New Cenozoic records of genera and families from New Zealand (Mollusca, Gastropoda): highlights from Phillip Maxwell's collection

Abstract

Six new gastropod species collected by Phillip Maxwell and a seventh from North Auckland are new records from New Zealand. Globularia maxwelli from Otaio Gorge, South Canterbury (Mangaorapan, Early Eocene) is the first confirmed occurrence of the gastropod family Ampullinidae (Campaniloidea) in New Zealand. Clavilithes philmaxwelli, also from Otaio Gorge (Mangaorapan), is also the first record of Clavilithes (Fasciolariidae) from New Zealand. Maxwellinatica phillipi from Mount Harris Formation (Altonian, Early Miocene), South Canterbury, resembles Cernina (Ampullinidae) but is a new genus and species referred to the Naticidae. Pellasimnia maxwelli (Ovulidae, Ovulinae) from Bridge Point, Kakanui (Runangan, Late Eocene) is the first fossil record of the genus in New Zealand. A second New Zealand ovulid, Prosimnia blackae n. sp. (Prionovolvinae), is described from Tokatoka, North Auckland (Otaian, Early Miocene). Haloceras maxwelli is the fourth (and earliest) world fossil record of the rare family Haloceratidae, from Evans Crossing, Pareora River, Canterbury (Bortonian, Middle Eocene). The neritid Neritina maxwellorum is also from Evans Crossing, Pareora River, Canterbury (Bortonian). The new taxa help confirm warm sea temperatures in New Zealand during Eocene to Miocene time.

Keywords:

• Ampullinidae
• Clavilithes
• Globularia
• Haloceras
• Naticidae
• Neritina
• new genus
• new species
• Pellasimnia
• Prosimnia

Introduction

In this issue commemorating the life and work of Phillip Maxwell, it is very appropriate to celebrate one of his most important contributions: the field-collecting of New Zealand Cenozoic fossil molluscs. Phil was a keen and sharp-eyed collector from the time he first became interested in fossil molluscs. His knowledge of fossil localities and the molluscs occurring at them in Canterbury, Otago and Southland was unsurpassed. He discovered or collected extensively from richly diverse faunas in many areas, several of which remain largely undocumented at present, notably the Early Eocene faunas of the area around ‘Pentland Hills’ Station in the Waihaorunga Valley (Beu & Maxwell 1990: 89). Some of his other new discoveries were also mentioned by Beu & Maxwell (1990), such as the strombid gastropod Phil referred to as Rimella (Maxwell 1971: 766; Beu & Maxwell 1990: 100), later named in the closely related genus Ectinochilus (Burger & Kronenberg 2006). At least a further 1000 species await recognition beyond the almost 5800 listed by Phil (Maxwell 2009), and Phil's research was vital in revealing the great diversity of this fauna. We selected six highlights from Phil's collection to record here, adding a further new species from Northland for comparison.

Familial and higher classification in this paper follows Bouchet et al. (2005), in which informal clade names are used for all categories above the superfamily. Authorship of and references to these names also can be found in Bouchet et al. (2005).

Systematic palaeontology

Phylum Mollusca

Class Gastropoda

Clade Neritimorpha

Superfamily Neritoidea Rafinesque, 1815

Family Neritidae Rafinesque, 1815

Subfamily Neritininae Poey, 1852

Genus Neritina Lamarck, 1816

Laphrostoma Rafinesque 1815: 144. Replacement name for Neritina Lamarck (‘1809’, vernacular) 1816 (also misspelled Lamphrostoma, Lamprostoma; Keen & Cox 1960: 282) (replaced by Neritina Lamarck, 1816, in the spirit of ICZN Opinion 119 1931).

Neritina Lamarck 1816: pl. 455, ‘Liste des objets représentés dans les planches de cette livraison’:11. Type species (ICZN Opinion 119 1931): Nerita pulligera Linnaeus, 1767, Recent, tropical Indo-West Pacific (Madagascar, Andaman Islands, Southeast Asia, Taiwan, North and South Pacific islands but not French Polynesia; Haynes 2001: 36).

Neritella Gray 1847: 146. Type species (by original designation): Nerita pulligera Linnaeus, 1767.

Chernites Gistel 1848: 168. Type species (by monotypy): Nerita pulligera Linnaeus, 1767.

Labialia (ex Megerle von Muhlfeld ms) Scudder 1882: 177. Type species (according to Keen & Cox 1960): Nerita pulligera Linnaeus, 1767 (nomen nudum according to Neave 1939).

Onychina (ex Megerle von Muhlfeld ms) Scudder 1882: 234. Type species (according to Keen & Cox 1960): Nerita pulligera Linnaeus, 1767 (nomen nudum according to Neave 1940).

Remarks. Neritina Lamarck, 1816 was adopted in ICZN Opinion 119 (1931) as the valid name, officially in place of Theodoxus Montfort, 1810 , Clithon Montfort, 1810, and Neritina Rafinesque, 1815 (nomen nudum). Nevertheless, the status of the case is a little obscure as Laphrostoma Rafinesque, 1815 was ignored in the application and Theodoxus and Clithon are now considered by most taxonomists to be distinct genera. The emphasis of ICZN Opinion 119 was to restore Neritina Lamarck, 1816 as the valid name for the genus typified by N. pulligera (Linnaeus, 1767) , so we continue the usage of Neritina here.

Neritina maxwellorum n. sp. Fig. 1A–E.

Figure 1.  A–E, Neritina maxwellorum n. sp., holotype, NMNZ M.284526, J39/f7686, Waihao Greensand, Bortonian (Middle Eocene), left bank Pareora River, Evan's Crossing, S Canterbury; A, D, E, uncoated, showing colour pattern; B, C, coated with MgO, showing top of outer lip ascending spire. Scale bar applies to all figures.

Type material. Holotype in Museum of New Zealand Te papa Tongarewa (NMNZ) M.284526, New Zealand fossil record no. J39/f7686 (http://www.fred.org.nz), Waihao Greensand (Bortonian, Middle Eocene), left bank from 10–30 m upstream to 5–15 m downstream from Evans Crossing, Pareora River, South Canterbury; collected by PA Maxwell, 1992; grid reference J39/539437 (the locality recorded by Maxwell (2003) for a succession of Athleta species).

Distribution. Middle Eocene, South Canterbury.

Dimensions. H (greatest dimension) 11.6, D (parallel to apertural plane) 9.2, D (normal to apertural plane) 5.0 mm.

Description. Shell thin and fragile, small for genus, retaining bright colour pattern; smooth, low and limpet-like, with flared last whorl enveloping remainder of shell, maximum diameter 79% of height; consisting essentially of last teleoconch whorl. Protoconch abraded. Spire flat, with part of previous whorl just visible at apex; dorsal surface flat, inclined away from aperture at low angle to horizontal; very weakly defined, rounded ridge margining dorsal surface extending anteriorly, producing slightly trapezoidal outer lip profile, which contracts towards base. Outer lip thin and sharp; dorsal posterior (adapical) margin of lip extending anteriorly beyond aperture to form low, thin ridge extending along apical margin of inner lip and slightly further adapically, separated from aperture by shallow groove; ridge curving evenly in quarter-circle to form raised, low, narrow dorsal ridge curved back to spire apex. Inner lip wide, smooth, flat except for slight central hollow, sloping inwards towards aperture, not coloured, forming callous pad hiding previous whorl; outer margin bordered by narrow, sharp ridge all around except against parietal area, where it blends smoothly into previous whorl; columellar edge smooth but shallowly embayed over central half, with weakly protruding nodule at each end of embayment. Exterior sculptured only with few obvious growth checks and faint growth lines, apparently polished in life; entirely coloured with coarse, dark reddish-brown network of intersecting and anastomosing lines and bands, leaving bold pattern of large, spirally elongate, oval to tent-shaped greenish-cream maculations.

Remarks. The Neritidae is a large and diverse family. Nerita Linnaeus, 1758 and most genera with similar species occupy high-tidal rocky shores and have thick shells. Consequently, they differ from the present species in having a thick outer lip with a wide, obviously bevelled edge. Species of Nerita also have a much more evenly inflated shell, a taller spire, an obviously toothed inner lip margin and coarser sculpture than the present species. Initially we thought a position in Theodoxus Montfort, 1810 possible for the new species, but this genus occurs in freshwater in Europe, the Middle East and North Africa only. Zettler (2008) recently revised the species of Theodoxus living in Germany. Several colour forms he illustrated are similar to Neritina maxwellorum n. sp. (T. fluviatilis: Zettler 2008: figs. 19c–f, 21a–f, 22e, f, 23a–d). Bandel (2001:78–96) provided a catalogue of European and Middle Eastern fossil and living species of Theodoxus, with many illustrations. A genus occurring in the tropical Indo-West Pacific region is obviously a more appropriate taxonomic position than Theodoxus for the new species. Genera with species that are similar to Neritina maxwellorum n. sp. in their low, limpet-shaped, thin shell, flat spire, weak sculpture and expanded, almost flat, smooth inner lip include Clithon Montfort, 1810, Neritina, Neripteron Lesson, 1830, Clypeolum Récluz, 1842, and Dostia Gray, 1842.

As with most other fossil Neritidae of all ages, Neritina maxwellorum n. sp. retains a bright colour pattern. The same type of lozenge- or tent-shaped colour pattern is seen in some species of many neritid genera, but Clypeolum and Septaria species have a flattened, limpet-shaped shell with a posterior marginal apex and Neripteron and Clithon all have markedly taller spires than the new species. Most Clithon species also bear spines around the shoulder of the shell. These characters leave the genera Neritina and Dostia as most suitable to include the new species. Some species of Dostia (e.g. Tsuchiya in Okutani 2000: 107, pl. 53, fig. 31; Haynes 2001: 40; Dharma 2005: pl. 10, fig. 6; Robin 2008: pl. 62, figs. 5–6; Lozouet & Plaziat 2008: pl. 13, figs. 6–7, included in ‘Pseudodostia?’) and Neritina (e.g. Tsuchiya in Okutani 2000: 107, pl. 53, fig. 25) also have a lozenge-shaped colour pattern.

Characters of Neritina (Neritina) listed by Keen & Cox (1960: 284) that are shared with the present new species are its flat spire and expanded last whorl, thin outer lip, broad, flat, smooth inner lip and the outer lip extending apically above the last whorl to produce a spiral ridge of outer lip above the aperture. The ridge is separated from the inner lip by a shallow groove, and produces a projecting point near the shell apex in some species. Lozouet & Plaziat (2008) illustrated the molluscan fauna of present-day Philippines mangroves in colour, including eight genera and 22 species of Neritidae. They illustrated a species identified as Neritina cf. pulligera (Lozouet & Plaziat 2008: 55, pl. 14, figs. 4–5), differing from N. maxwellorum n. sp. in its less expanded last whorl, its uniform pale olive-green shell lacking a bright colour pattern, its finely dentate inner lip margin and its more obvious spine on the shell apex. Other illustrations of N. pulligera, the type species of Neritina (Starmühlner 1976: pl. 11, figs. 104–110; Abbott & Dance 1982: 54, lowest left fig.; Tsuchiya in Okutani 2000: 105, pl. 53, fig. 22; Dharma 2005: 70, pl. 10, fig. 2a–b) resemble N. maxwellorum n. sp. particularly closely in all characters other than the lack of a bright colour pattern. However, Haynes (2001: 36) stated that the type species N. pulligera has a ‘blackish network pattern’ when young. Neritina canalis GB Sowerby I, 1825 from Tahiti (Pointier & Marquet 1990: 218, pl. 1, figs. 3–5) is also similar to N. maxwellorum n. sp. in all characters, including a pale colour pattern of stripes and lozenges. Another species, Pseudodostia? siquijorensis (Récluz, 1843) (Dharma 2005: pl. 10, fig. 15, included in Puperita; Lozouet & Plaziat 2008: 55, pl. 13, figs. 6–7; Eichhorst in Poppe 2008: 268, pl. 79, fig. 2a–b, included in Neripteron; Robin 2008: pl. 62, fig. 5, included in Dostia), also resembles the new species quite closely, having a particularly similar colour pattern of large cream lozenges surrounded by dark reddish-brown lines and colour bands. It is also only 13mm long, similar to the 11.6 mm of N. maxwellorum n. sp., whereas typical Neritina species are 20–35 mm long.

However, Dostia? siquijorensis differs from N. maxwellorum n. sp. in that it lacks the distinctive spiral ridge of inner lip margin extending around the spire, its aperture is less expanded (diameter 69% of height) and the inner margin of the inner lip bears 6–7 obvious, small, narrow teeth that are not present on the virtually smooth inner lip of N. maxwellorum n. sp. and other Neritina species. Species included in Neritina (Dostia) by Wilson (1993): 41, pl. 2), particularly the type species, N. (Dostia) violacea Gmelin, 1791, also are similar, so this is possibly a more appropriate genus or subgenus to include N. maxwellorum n. sp. However, the generic classification of N. violacea and related species differs greatly between authors (Komatsu 1986: 173, fig. 6; Lozouet & Plaziat 2008: 55, pl. 14, figs. 1–3; Robin 2008: pl. 62). Haynes (2005: table 2) listed the six subgenera that have been proposed for Neritina (Neripteron, Neritona, Nereina, Vitta, Vittina, Vittoida), but noted that supposedly diagnostic characters of their radulae and spermatophores vary within species. Obviously, a molecular study is required to stabilise the generic classification of Neritidae. In the meantime, we consider Neritina to be the most appropriate genus to include N. maxwellorum n. sp. The flat spire, the greatly expanded last whorl (with diameter 79% of height), the narrow, weakly developed ridge at the top of the outer lip above the aperture ascending to the spire apex and the bold colour pattern of large, oval, faintly greenish-cream lozenges on a dark reddish-brown ground are distinctive characters which distinguish Neritina maxwellorum n. sp. from all other Neritidae we are aware of.

Reference to Neritina, rather than to the high-tidal rocky shore genus Nerita, suggests that N. maxwellorum n. sp. inhabited freshwater or possibly a brackish river mouth in an estuary. Such neritids commonly occur on the surface of the mud or on pebbles and rock outcrops near the mouths of rivers in the tropical Indo-West Pacific (e.g. Philippines habitat photographs: Eichhorst in Poppe 2008). Haynes (2001: 36) recorded Neritina pulligera living up to 50 km inland from the coast and Pointier & Marquet (1990: 218) recorded N. canalis living in ‘the upper parts of rivers’. Neritina maxwellorum n. sp. was therefore probably a freshwater species carried into the Evans Crossing deposition site by a river following a flood. Some other taxa present at Evans Crossing, such as Monalaria, imply a shallow deposition site in perhaps 50–100 m of water. The glauconite-rich matrix could reflect a landmass of low relief with little erosion of siliciclastic sediment, rather than deposition a long way from land. The presence of a neritid strengthens the interpretation of deposition as occurring in tropical shallow water near land at the present site of Evans Crossing.

Neritidae are very poorly represented in the New Zealand Cenozoic fossil record. Only two taxa have been recorded previously (Beu & Maxwell 1990: 405; Maxwell 2009: 240). The extant species Nerita (Lisanerita) melanotragus EA Smith, 1884 (Spencer et al. 2007; Frey & Vermeij 2008) is recorded fossil from Kaawa Creek, southwest Auckland (Opoitian, Early Pliocene) (Laws 1936) and Holocene terrace faunas at Mahia Peninsula (research in progress by the first author). The other is the small, colourful species Smaragdia or Pictoneritina pomahakaensis (Finlay, 1924) , which is locally common in the estuarine beds at Pomahaka, Southland (Duntroonian, Oligocene). Pictoneritina? pomahakaensis seems very similar to P. oualaniensis (Lesson, 1831) and similar small, high-spired, brightly coloured species of Pictoneritina (e.g. Starmühlner 1976: pl. 6, figs. 18–25; Tsuchiya in Okutani 2000: 109, pl. 54, fig. 37; Haynes 2001: 48–49; Haynes 2005: fig. 1G; Eichhorst in Poppe 2008: 266, pl. 78, figs. 1–7, 9, 11; Lozouet & Plaziat 2008: 96, pl. 12, figs. 3–4). Nerita melanotragus differs from Neritina maxwellorum n. sp. in its larger size (reaching 25–32 mm long), much more strongly convex teleoconch, uniform black coloration of the exterior and more prominent sculpture on the white inner lip. The rarity of this group in New Zealand is due to two factors: the high-tidal rocky shore or estuarine to freshwater environments inhabited by Neritidae and the rarity of these environments in the fossil record, combined with the warm-temperate to subtropical climate of New Zealand for much of Cenozoic time. Neritidae are almost entirely tropical at present, with their highest diversity on high-tidal tropical shores and in tropical estuaries and streams; only a few species of ‘black nerites’ resembling N. melanotragus linger into temperate waters. The new species of Neritina described here seems likely to represent a diverse neritid fauna that inhabited New Zealand during subtropical Early Eocene to Middle Miocene times, in environments that left almost no fossil record.

Etymology. The species name honours both Phillip and Sue Maxwell. Sue helped Phil greatly in collecting fossils over many years.

Clade Caenogastropoda

Clade Sorbeoconcha

Superfamily Campaniloidea Douvillé, 1904

Family Ampullinidae Cossmann, 1918

Remarks. Gastropods now included in Ampullinidae have traditionally been included in the family Naticidae (Clade Littorinimorpha, Superfamily Naticoidea; Bouchet et al. 2005), and were recognised as Naticidae subfamily Ampullospirinae (or Ampullininae, etc.) in all recent major taxonomic reviews of Naticidae (Marincovich 1977; Majima 1989; Kabat 1991). Cossmann (1925) recognised a family ‘Euspiridae’ separate from Naticidae for the Ampullina-like taxa, prophetically locating them among the Loxonematoidea: ‘It emerges manifestly from the preceding that the Euspiridae [that is, Ampullinidae] have their stem in the Loxonematacea, in spite of their naticiform appearance, and that it is a grave error to confuse them with the family Naticidae, which has … a very different, capuloid origin’ (free translation of Cossmann 1925: 12). He was also the first to point out that no calcareous opercula have ever been found associated with species of Ampullinidae (Cossmann 1925: 12), and it is evidently conchiolin. Stewart (1927: 330–339, Ampullininae, ‘?Naticidae’), Woodring (1928: 391–394, ‘Ampullinae’, sic) and Vredenburg (1928: 399, ‘family Euspiridae’) also treated the group as a family or subfamily separate from but alongside Naticidae, containing the taxa related to Ampullina. Cox (1930a:170; 1931: 38) treated the family as Ampullospiridae, separate from and alongside the Naticidae. He pointed out that Euspira is a naticid (now regarded as a synonym of Lunatia Gray, 1847), and discussed the name Ampullina Bowdich, 1822 . Cox (1948: 19) again treated ‘Amaurellinidae (= Ampullospiridae)’ as a family separate from but alongside Naticidae.

Naticidae are well-known for their carnivorous habit, boring through the shells of their molluscan prey to reach the tissue inside. They use a unique accessory boring organ (Carriker 1981; Kabat 1990) and produce characteristic circular, bevelled boreholes in Recent and fossil molluscan shells. Kase (1990: 565) described the anatomy for the first time and Kase & Ishikawa (2003) illustrated for the first time the anatomy and feeding behaviour of the sole living species of Ampullinidae, the Recent Philippine Islands species Cernina fluctuata (GB Sowerby I, 1825) (Fig. 2D). Its radically different anatomy supports a position in the Architaenioglossa, well separated from the Naticoidea (Ponder & Lindberg 1997). Kase & Ishikawa (2003) recognised that Cernina is a herbivorous relative of the tall-spired gastropod Campanile, grazing macroalgae on shallow sand flats in the eastern Philippines. Fresh (transported?) specimens have however also been collected in up to 150 m of water, so it possibly grazes algae throughout the photic zone. It lacks a propodium, the large anterior shield-like structure that aids naticids in ‘ploughing’ through sediment to find their infaunal bivalve prey. It also has no accessory boring organ, and the fore-gut of living specimens is filled with large pieces of algae. The distinctive shell character of family Ampullinidae is the layer of callus (identified as the sheath by some authors; Wrigley 1946: 88, fig. 1; noting that it is equivalent to the term ‘limbe’ used by French palaeontologists; Kase & Ishikawa 2003: fig. 2B) alongside the inner lip and around the umbilicus, overlain by the inner lip callus. By inference, all similar naticid-like gastropods with a callus layer around the umbilical area, overlain by the apertural callus and with no funicle in the umbilicus, belong in Ampullinidae rather than Naticidae (although many ampullinids are imperforate). The most extensive coverage of the family after that of Cossmann (1925) and before that of Kase & Ishikawa (2003) was by Cox (1930a: 170–177; 1931: 38–42), treating northern Indian Palaeocene–Eocene fossils. Here a slightly different idea of the genera is gained from that of Cossmann (1925). Cox (1931: 38) recognised the genera Crommium Cossmann, 1888 , Pachycrommium Woodring, 1928, Euspirocrommium Sacco, 1891 , Amaurellina, and Ampullella Cox, 1931 in the family ‘Ampullospiridae’. Numerous other genera have since been included. Examples of species belonging to several genera of Ampullinidae were illustrated by Cox (1930a: pl. 18; 1931: pl. 1) and Wrigley (1946), and a large number of Paris Basin species and genera was illustrated by Cossmann & Pissarro (1907–1910: pls 9–11).

Figure 2.  Paris Basin Eocene and Philippines Recent Ampullinidae, all coated with MgO. A, Globularia sphaerica (Deshayes), WM5105, upper Calcaire Grossier, Lutetian (Middle Eocene), Liancourt, Paris Basin, France. B, Ampullina grossa (Deshayes), WM5104, Sables Moyens, Eocene, Le Ruel, Paris Basin, France. C, Globularia sigaretina (Lamarck), type species of Globularia Swainson, 1840; WM4995, Eocene, Paris Basin, France. D, Cernina fluctuata (GB Sowerby I), type species of Cernina Gray, 1840; WM19016, Recent, 20 m, off Balabac Island, Palawan, Philippines. E, Crommium acutum (Lamarck), type species of Crommium Cossmann, 1888; WM5103, Calcaire Grossier, Lutetian (Middle Eocene), Paris Basin, France. Scale bar applies to all figures.

Bouchet et al. (2005) pointed out that Lozouet et al. (2001: 21) placed Ampullinidae in a separate superfamily Ampullinoidea Cossmann, 1918. However, this was before information was available from J Healy (pers. comm. to P. Bouchet in Bouchet et al. 2005: 275, note 98) on the sperm morphology of Cernina fluctuata; this supports a position in superfamily Campaniloidea.

The family Ampullinidae is represented in the Australian Cenozoic fauna only by Ampullina effusa Tate (1893: 327, pl. 10, figs. 2–2a; Darragh 1970:167) in the late Eocene fauna of the Adelaide Bore, Kent Town, South Australia. Tate (1893: 328) compared this species with Natica acuminata Lamarck, 1804 (Lutetian (Eocene), Paris Basin; Cossmann & Pissarro 1910: pl. 11, fig. 64bis-3) and N. levesquei d'Orbigny, 1850 (Cuisian (Eocene), Paris Basin; Cossmann & Pissarro 1910: pl. 11, fig. 64bis-5). N. acuminata is the type species of Euspirocrommium Sacco, 1891. Darragh & Kendrick (2008: 235, fig. 2.16) referred an internal mould to Euspirocrommium from Eocene silicified sandstone near Kalbarri, Lower Murchison district, Western Australia.

Finlay & Marwick (1937: 57) expressly excluded their Palaeocene genus Amauropsona from ‘subfamily Ampullininae’ because it lacks the characteristic shape and the ‘basal limb’ of the aperture (that is, a sheath). The two included species, Amauropsona major (Marshall, 1917) and A. teres (Marwick, 1924), both from the Wangaloan (Palaeocene) fauna at Wangaloa, South Otago coast, and at Boulder Hill, near Dunedin, are tall-spired and resemble species of Pachycrommium and Euspirocrommium but lack the critical apertural characters of Ampullinidae. Finlay & Marwick (1937: 57) pointed out their similarity to the Arctic naticid genus Amauropsis Mörch, 1857 (type species: Natica islandica Gmelin, 1791 ; Wenz 1941: 1036, fig. 2965) and classified both Amauropsis and Amauropsona in the Naticidae near Lunatia Gray, 1847.

We reviewed all the material we are aware of from New Zealand that has been referred to family Ampullinidae and, at present, we retain only one specimen here. We also commenced this paper thinking that Maxwellinatica phillipi n. gen., n. sp. was an ampullinid, but we now refer to it as the Naticidae; this emphasises again the difficulty of distinguishing these families. At least four New Zealand species were referred to as Ampullina previously, by Suter (1915: 10–11, 1917: 11) and Marshall (1917: 452), but these have since been referred to either Globisinum Marwick, 1924 or Carinacca Marwick, 1924, both in family Naticidae. Maxwell (1992: 105, pl. 13a, f) transferred Globisinum elegans (Suter 1917) to Lunatia. ‘Ampullina’ carinata (Hutton, 1877) of Suter (1915: 10) (a junior primary homonym) was renamed Micreschara (Micromphalina) huttoni by Marwick (1924: 578) and is now included in Naricava Hedley, 1913 , family Tornidae (Beu & Maxwell 1990: 406; Maxwell 2009: 241). Dell (1956: 44) described the standard naticid propodium and the unusually large egg mass of the living species Globisinum drewi (Murdoch, 1899) , unequivocally demonstrating that Globisinum is a naticid.

One other species that has been tentatively referred to as Ampullinidae in the past on unpublished GNS labels is a small (12–15 mm high) subspherical gastropod in the Late Cretaceous–Early Palaeocene succession exposed along the Jed River near Gore Bay, North Canterbury. Incomplete specimens were tentatively identified by CA Fleming as Crommium sp. (Ampullinidae), but better material in NMNZ collected by Alan Tennyson shows this to be a large species of Ringiculidae similar to Eriptycha punamutica Wilckens (1922: pl. 5, fig. 5a–c; Stilwell 2007: fig. 2F–H).

Several species of typical Paris Basin Eocene and Philippines living Ampullinidae are illustrated here for comparison with Globularia maxwelli n. sp. and Maxwellinatica phillipi n. gen., n. sp.: Globularia sphaerica (Deshayes, 1832) , Fig. 2A; Ampullina grossa (Deshayes, 1864) , Fig. 2B; Globularia sigaretina (Lamarck, 1804) , type species of Globularia Swainson, 1840, Fig. 2C; Cernina fluctuata (GB Sowerby I, 1823), type species of Cernina Gray, 1840 , Fig. 2D; and Crommium acutum (Lamarck, 1804) (= Ampullaria willemetii Deshayes, 1825) , type species of Crommium Cossmann, 1888 (Le Renard & Pacaud 1995: 98), Fig. 2E.

Genus Globularia Swainson, 1840

Globulus JdeC Sowerby 1835, in 1812–1846, index: 246 (junior homonym of Globulus Schumacher, 1817, Gastropoda).

Globularia Swainson 1840: 345 (replacement name for Globulus JdeC Sowerby, 1835, junior homonym). Type species (by subsequent designation, Herrmannsen 1847: 480): Ampullaria sigaretina Lamarck, 1804, Eocene, Paris Basin.

Globularia maxwelli n. sp. Fig. 3C.

Type material. Holotype NMNZ M.281937, cemented shellbeds (Kauru Formation), Mangaorapan (Early Eocene), Otaio River, South Canterbury, c. 300 m downstream from Otaio Gorge Bridge and 40 m downstream from top of lower coal bed; grid reference J39/454297; collected by PA Maxwell, 1994; equivalent to GNS Science locality GS5618, NZ fossil record no. J39/f8539, the locality of the fauna described by Marwick (1960).

Distribution. Early Eocene, South Canterbury.

Dimensions. Holotype: H (outer lip and base slightly incomplete) 18.7, D 19.9 mm.

Description. Shell small for genus, squat and solid, imperforate, width slightly exceeding height, smooth except for a few faint growth ridges. Protoconch severely abraded. Teleoconch of c. 4 whorls with very low spire, only slightly elevated above sutural ramp of last whorl, suture descending slightly over last quarter-whorl; weakly but evenly inflated sutural ramp horizontal, so deeply impressed suture lies below ramp crest on last 1–2 whorls of spire; periphery strongly and evenly convex high up on last whorl, with maximum convexity slightly lower than level of sutural insertion; convexity decreasing below periphery to form weakly inflated, anteriorly tapered base. Outer lip margin broken away slightly; course straight and vertical (orthocline) for most of height of last whorl, weakly retracted to suture adapically; inner lip with thin, smooth callus in parietal area, scarcely thickened at crest of parietal bulge, but obviously thickened at adapical junction with outer lip; inner lip lightly thickened in columellar excavation below parietal area, smoothly flared in curve c. 3.5mm wide over previous whorl, almost hiding narrow (2 mm wide), short rim of sheath with sharply defined left edge, covering umbilical area.

Remarks. Although we know of only a single specimen of this new species, it is such a remarkable and distinctive addition to the New Zealand fauna that it deserves to be named, allowing the first authentic recognition of family Ampullinidae. Globularia maxwelli n. sp. is distinguished from other Globularia species by its small size, its low, wide, almost flat spire, and the narrow sheath alongside the inner lip callus. The type species of Crommium Cossmann, 1888, Crommium acutum (Fig. 2E; Cossmann 1925: 42, pl. 4, figs. 1–2) is rather larger (GNS WM5103, Paris Basin, Lutetian: H 35.9, D 30.5 mm) and a little taller (height slightly exceeding diameter), with a slightly taller, narrow spire with concave outlines and with a clearly open umbilicus. Although the spire is low, it does not have the wide, antero-posteriorly compressed appearance of the spire of G. maxwelli n. sp. Also, the sheath in C. acutum is represented only by an extremely narrow ridge, less than 1mm wide, alongside the lower part of the inner lip below the umbilicus. Globularia species also have a much wider area of revealed sheath than Crommium species. Therefore, it seems more appropriate to place G. maxwelli n. sp. in Globularia than in Crommium. In some characters Globularia maxwelli n. sp. resembles Paris Basin Ampullina species as much as Crommium acutum, but Ampullina species (e.g. A. depressa Lamarck, 1804; A. grossa Deshayes, 1864; Fig. 2B) have a taller spire than either Crommium or Globularia species and do not resemble G. maxwelli n. sp. closely. Globularia sphaerica is particularly similar to G. maxwelli n. sp., having a closed umbilicus and a clearly visible curve of sheath to the left of the lower inner lip callus, but again has a more spherical, naticoid shape and a taller spire. The most closely similar illustration we have seen is Cox's (1930a: pl. 18, fig. 19), one of Globularia brevispira (Leymerie, 1846) , which only has a slightly taller spire and a similarly tapered last whorl to G. maxwelli n. sp. but has a much narrower area of sheath and a clearly (if narrowly) open umbilicus. Some specimens of G. ickei (Martin 1914: 173, pl. 6, figs. 152, 154) from the Late Eocene–Oligocene Nanggulan fauna in Java have a similarly low spire to that of G. maxwelli n. sp., but the inner lip callus is thicker, particularly in the parietal area. Palaeocene–Eocene species of Globularia in southern Europe were reviewed by Okan & Hoşgör (2008). Their records from Turkey (dated by co-occurrences with numulitid Foraminifera) are earlier than those of the same species in Western Europe. G. sireli (Okan & Hoşgör 2008: 793, pl. 2h–m) is similar to G. maxwelli n. sp., but again is larger (H 28–31, D 25–28 mm) and has a taller spire than G. maxwelli n. sp.

Etymology. This species is named in memory of Phillip Maxwell.

Clade Littorinimorpha

Superfamily Naticoidea Guilding, 1834

Family Naticidae Guilding, 1834

Genus Maxwellinatica n. gen.

Type species. Maxwellinatica phillipi n. sp., Altonian (late Early Miocene), South Canterbury, New Zealand.

Diagnosis. A genus of Naticidae; protoconch low, almost planispiral; teleoconch poliniciform, slightly lower than wide, with weakly flattened area of outline below sutural ramp producing slight taper towards apex. Inner lip bearing huge, thick, wide, smoothly rounded parietal callus extending down to cover upper half of umbilical area, protruding anteriorly in front of remainder of shell in both dorsal and lateral views, left margin sharply defined (in conventional spire-up apertural view); narrowing to low, wide, flat, inner lip callus, a smooth zone margining apertural edge of lower umbilical area. Lower half of umbilical area revealed, a rather narrow but clearly defined, shallow, ridge-margined zone of fine, irregular axial ridgelets; central straight, narrow chink possibly either an umbilical remnant or an individual character. Exterior sculpture of many narrow, shallow, widely spaced spiral grooves, prominent and very similar to those of Eunaticina papilla (Gmelin, 1791) in zones on sutural ramp and outside circum-umbilical ridge, weaker between, scarcely discernible around central third of last whorl.

Remarks. The taxonomic position of this new genus and species is not obvious. At first we assumed that the smooth, anteriorly bulging, rounded inner lip callus (Fig. 3A–B, D–E) implies a close relationship with Cernina fluctuata (GB Sowerby I, 1823) (Ampullinidae) (Fig. 2D), in which a similar callus is well developed, and the teleoconch looks generally similar. However, the teleoconch of C. fluctuata is taller, the parietal callus blends smoothly into the previous whorl, and the lower part of the inner lip, below the parietal callus, is much more deeply excavated in C. fluctuata than in Maxwellinatica phillipi n. gen., n. sp. Another clue that this might not be the correct relationship came from Kase & Ishikawa's (2003: 404, fig. 3B–D) statement that the relatively tall protoconch of all the ampullinids they had studied, including Cernina fluctuata, is a defining character of family Ampullinidae as all naticids have a very low protoconch. The very low, almost planispiral, protoconch of M. phillipi n. sp. is clearly distinct from that of the material of C. fluctuata we have examined, even though that of M. phillipi n. sp. is not well preserved. An unusual character present on C. fluctuata but not on any Naticidae we are aware of, including M. phillipi n. sp., is the fine, rather widely separated, regular, shallow axial grooves that cover the entire teleoconch exterior, other than the apertural callus. These are visible under low-power enlargement with a light microscope, but are difficult to see with the naked eye. However, similar fine axial grooves shown on the teleoconch surfaces of most of the specimens in Fig. 2, are particularly clear on Globularia sigaretina (Fig. 2C), and the grooves possibly provide a diagnostic character of Ampullinidae. A possible relationship with such naticids as Eunaticina, Sinum and Gennaeosinum is also suggested by the spiral sculpture of M. phillipi n. sp. While many species of Ampullinidae have a sculpture of very fine spiral threads, and Stewart (1927: 331) stated that ‘typical Ampullina... [has] very finely punctate spiral lines’, sculpture like that of Eunaticina has not been described in Ampullinidae previously. A few species have coarse, prominent spiral cords, e.g. ‘Vanikoroia’ javana Martin (1914: 170, pl. 6, figs. 148, 148a; Late Eocene, Nanggulan, Java); Ampullinidae, Dr Tomoki Kase (National Science Museum, Tokyo pers. comm. October 2008). Some species of the naticid genus Polinices also have similar sculpture, e.g. P. propeovatus (Marwick, 1924), Waiauan–Opoitian (late Middle Miocene–Early Pliocene), New Zealand (Beu & Maxwell 1990: pl. 29 l). Similar sculpture is also present in the Antarctic–subantarctic naticid genus Sinuber (Dell 1990: 100, figs. 225, 241). Similar but slightly coarser spiral sculpture to that of Eunaticina is displayed also by Nerinatica paytensis (Olsson 1930: 68, pl. 5, figs. 3, 6–7, 9, 11–12; Eocene, Peru), which also has a low umbilical bordering ridge and a low funicle, forming a spiral groove within the umbilicus, and an unusually thick parietal callus. However, the callus is nowhere near as massive as that of Maxwellinatica n. gen., and the low spire with flat outlines and the small size (11×12 mm) give Nerinatica a very different appearance. Nerinatica is likely closely related to Sinum and Eunaticina, differing mainly in its much thicker shell. Another character separating Maxwellinatica n. gen. from Cernina and other Ampullinidae is the ridge-margined umbilical area. A ridge or obvious deep groove bordering or within the umbilicus is common in Naticidae, e.g. in Carinacca and Tahunacca in New Zealand (Maxwell 1992: pl. 12) and in several tropical Indo-West Pacific Recent species of Polinices, Natica and Naticarius. Such a distinct, narrow, closely bordering ridge has not been recorded in any Ampullinidae however, although a similar but more prominent peribasal ridge, widely separated from the umbilicus, is present in the ampullinid genus Gyrodes. In total, the characters of Maxwellinatica phillipi n. gen., n. sp. have more in common with those of Naticidae and with Polinices in particular, than with those of Ampullinidae. It also seems unlikely that a close relative of the tropical genus Cernina would occur in New Zealand Early Miocene rocks, in Mount Harris Formation in North Otago-South Canterbury, where such tropical taxa as cowries (Cypraeidae and Ovulidae) are lacking.

Etymology. The generic name is a combination of the name Maxwell and the generic name Natica. It is a great pleasure to name this distinctive new genus in memory of its collector, Phillip Maxwell. Gender feminine.

Maxwellinatica phillipi n. sp. Fig. 3A–B, D–E

Type material. Holotype in Museum of New Zealand Te Papa Tongarewa, NMNZ M.281938, with one slightly incomplete, chalky paratype NMNZ M.287804, both from New Zealand fossil record no. J40/f0222, Mount Harris Formation (Altonian, late early Miocene), Elephant Hill Stream, first outcrop behind pine tree on left bank c. 200 m upstream from bridge on Elephant Hill Road, c. 6 km north of Ikawai, between Waihao Downs and Waitaki Valley, South Canterbury; grid reference J40/392975; collected by PA Maxwell, 4 March 1992.

Distribution. Early Miocene, South Canterbury.

Dimensions. Holotype: H (slightly incomplete) 21.2, D 23.0 mm.

Description. Shell of moderate size, naticiform, with moderately low spire, width slightly exceeding height. Protoconch naticiform, low, of c. 2 weakly convex whorls, but abraded and slightly chalky on both specimens; termination unclear. Teleoconch of c. 3.5 whorls, spire whorls and sutural ramp of last whorl evenly inflated, periphery and base evenly and strongly inflated on last whorl; profile slightly flattened, sloping outwards towards base between sutural ramp and periphery on last whorl. Sculpture of very low, relatively wide, closely spaced, weakly convex-crested spiral cords, c. 18–20 on spire whorls, commencing as c. 8 narrower cords on sutural ramp and c. 10 wider cords below on early spire whorls, cords weakening and widening down teleoconch to form c. 15 narrow, shallow, widely spaced grooves on sutural ramp on early part of last whorl (to left of aperture), fading out slightly around whorl to leave c. 10–12 grooves on ramp at outer lip; c. 20 low, narrow, widely spaced grooves on base; area between (c. 1/3 of whorl height) almost smooth apart from prominent, irregular growth ridgelets over entire surface, rendering spiral grooves wavy and slightly irregular. Axial ridgelets strongly opisthocline, retracted a little to suture adapically, forming more prominent, curved, closely spaced, narrow ridges over sutural ramp in irregular areas, particularly forming 8 narrow ridgelets just behind aperture on holotype; moderately prominent and consistently present over basal ridge-margined area. Outer lip edge slightly broken away, apparently smooth and simple; anterior extremity of aperture incomplete. Inner lip bordered on left by area demarcated by low, narrow but obvious, spiral ridge; area slightly wider than inner lip callus, occupying 14% of diameter of base in holotype; sculptured with fine, close, irregular ridgelets parallel to margining ridge; upper (adapical) end of ridge disappearing beneath parietal callus, margining very narrow umbilical chink in centre between ridge and callus. Parietal callus very thick, smooth, strongly convex, sharply demarcated from previous whorl around left edge, bulging prominently in parietal area anterior to outer lip margin, with slightly flattened profile as it contracts to left edge, blending smoothly into inner lip callus below.

Remarks. The most distinctive character of Maxwellinatica phillipi n. sp. is its enormous, anteriorly protruding parietal callus, unique to this genus within Naticidae. Other distinctive characters are its low, wide, but obvious, simple spiral sculpture over much of the surface. It is more obvious on the sutural ramp and on the base than in the central area of the last whorl, which is almost smooth. The spiral sculpture is similar to but slightly less prominent than that of Eunaticina papilla. The other distinctive characters are described above in the generic diagnosis: the low, wide, but adapically tapered shape of the last whorl, produced by a short, dorsally inward-sloping area below the sutural ramp; the low, almost planorboid protoconch, with a deeply impressed suture and a weakly inflated whorl surface; and the ridge-margined area surrounding the lower half of the umbilicus. Also, unlike Cernina species, a very narrow chink of umbilicus is revealed alongside the parietal callus, lying in the centre of the quite wide area surrounded by the periumbilical ridge in Maxwellinatica phillipi n. sp.

Figure 3.  New Zealand Naticidae and Ampullinidae, all coated with MgO. A, B, D, E, Maxwellinatica phillipi n. sp., holotype, NMNZ M.281938, J40/f022, Mount Harris Formation, Altonian (late Early Miocene), Elephant Hill Stream, between Waihao Downs and Waitaki Valley, S Canterbury; A, standard apertural view; B, apical view; D, basal view with axis inclined, showing umbilical characters; E, right lateral view, showing protruding inner lip callus. C, Globularia maxwelli n. sp., holotype, NMNZ M.281937, Kauru Formation, Mangaorapan (Early Eocene), right bank Otaio River c. 300 m downstream from Otaio Gorge Bridge, S Canterbury (= GS5618, J39/f8539). Scale bar applies to all figures.

Species assigned to Cernina include the Eocene species C. hannibali (Natica hannibali Dickerson, 1914 , type species of the ‘section’ Cernina (Eocernina) Gardner & Bowles (1934: 243), from the Domengine Formation of California and the Umpqua Formation of Oregon, and the very similar Cernina chiapasensis Gardner & Bowles, 1934, from Eocene rocks near Chiapas, Isthmus of Tehuantepec, Mexico. Other, younger species assigned to Cernina were reviewed briefly by Majima (1989: 28–29):

1. Cernina fluctuata (GB Sowerby I 1825, appendix: xii; Reeve 1855: pl. 3, fig. 10; GB Sowerby II 1883: 99, pl. 455, fig. 17; Kase & Ishikawa 2003; Hollman in Poppe 2008: 482, pl. 186, figs. 5,7;=Ampullina lineata Pannekoek 1936: 57, pl. 3, figs. 36–37;=Neritilia fernandezi Kanno et al. 1982: 94, pl. 17, fig. 12a–b), Recent, Philippines; Miocene–Pleistocene, India, Kenya, Borneo and Java.

2. Cernina carlei (Finlay 1927: 498) (new name for Natica callosa (JdeC Sowerby 1840: 328, pl. 26, fig. 3), junior primary homonym of N. callosa de Cristofori & Jan, 1832 , Miocene–Pleistocene of Kenya, India, Borneo and Java (Noetling 1901: 283; Vredenburg 1928: 400; Cox 1930b: 107, pl. 12, fig. 11a–b; Beets 1941: 78; Cox 1948: 19, pl. 1, fig. 5a–b; Dey 1961: 54, pl. 5, figs. 3,5; Nuttall 1961: table 17; Nuttall 1965: 165; Harzhauser et al. 2009: fig. 2c–d). In our opinion this is a synonym of C. fluctuata.

3. Cernina fijiensis (Ladd 1945: 358, pl. 51A–B; Ladd 1977: 27, pl. 7, figs. 8–9; pl. 8, figs. 1–2). In our opinion this is a species of Globularia.

4. Cernina compressa (Basterot 1825 : 34, pl. 4, fig. 17; Cossmann & Peyrot 1919, in 1917–1924: 452, pl. 12, figs. 27–28; Cossmann 1925: pl. 3, figs. 1–2; Lozouet et al. 2001: 21, pl. 18, fig. 10), Miocene of France.

5. Cernina nakamurai (Otuka 1938: 37, pl. 3, figs. 19–21; Majima 1989: 28, pl. 1, figs. 1–4; Nakagawa 2009: table 1, pl. 2, fig. 15a–b, specimen c.100 mm high;=Globularia(?) monstrosa Hatai 1956: 1, figs. 1–3), Miocene of Japan.

The surprising aspect of the recognition of Maxwellinatica phillipi n. sp. is that it took so long for this relatively large gastropod to be discovered. Fossil molluscs were probably collected in this area first by Walter Mantell, a short time before his father reported an Eocene Dentalium from Hampden, Otago, in 1850 (Fleming 1965: 1156). Maxwellinatica was found at a locality with other diverse shallow-water molluscs, including Cucullaea, Limopsis (abundant), Zeacolpus, Struthiolaria and Polinices. This area of South Canterbury is surrounded by other localities in Mount Harris Formation with highly diverse molluscan faunas, although most others indicate a slightly to markedly deeper environment of deposition than the Elephant Hill Stream site. Perhaps an unusually shallow depth of deposition allowed this species to occur at Elephant Hill Stream.

Etymology. We commemorate the life work of Phillip Maxwell by naming in his honour this unexpected addition to the New Zealand fauna.

Superfamily Cypraeoidea Rafinesque, 1815

Family Ovulidae Fleming, 1822

Subfamily Ovulinae Fleming, 1822

Genus Pellasimnia Iredale, 1931

Pellasimnia Iredale 1931: 222. Type species (by original designation): Ovulum angasi Reeve, 1865 , Recent, Indo-West Pacific, Australia to Japan.

Pellasimnia maxwelli n. sp. Figs. 4A–B

Type material. Holotype NMNZ M.284525, with one incomplete paratype M.287805, pale pink and green tuff of Waiareka Volcanic Formation (here Runangan, Late Eocene), south side of Bridge Point, south of Kakanui, South Otago, collected by PA Maxwell, 1996; New Zealand fossil record no. J42/f0126, grid reference J42/437519.

Distribution. Late Eocene, South Otago.

Dimensions. Holotype: H 11.5, D 3.6 mm; paratype (incomplete internal mould): H 8.0, D 2.8 mm.

Description. Shell small for genus, tall and narrow (width 31% of height), completely smooth and involute, an almost cylindrical rod tapered weakly and very evenly towards both ends from a slightly and evenly swollen central region. Last teleoconch whorl completely enclosing entire earlier shell. Both ends slightly incomplete, to an unknown degree. Aperture tall and narrow, extending entire length of shell; lightly and evenly curved over entire height, with convexity to right; narrow and evenly slit-like over posterior half, but wider, with weakly excavated columella and outer lip expanded weakly to right over anterior third of height. Both lips completely smooth; outer lip evenly and smoothly enrolled, widest at mid-point, tapered evenly and weakly towards both ends; inner lip not thickened or callused. Interior characters of aperture not visible.

Remarks. Cernohorsky (1971: 126) and Powell (1971: 214; 1976: 145; 1979: 152, pl. 8, fig. 2, pl. 32, fig. 8) recorded a species they identified as Phenacovolva longirostrata (GB Sowerby I, 1828 ) living at the Poor Knights Islands, off eastern Northland, where it has been collected at depths of around 45 m, living on gorgonians (Powell 1979: pl. 8, fig. 2; Hart 1992, colour photograph of living animal in text). According to Liltved (1989), however, this species is actually P. wakayamaensis Cate & Azuma, 1973 . Hart (1994) recorded another species, identified as P. birostris (Linnaeus, 1767), occurring off Meyer Island, Kermadec Islands, the warmest-water environment in the New Zealand region at present. A third, unidentified species of Phenacovolva recorded by Spencer et al. (2009: 206) was collected off Macauley Island, Kermadec Islands. These species and many others occurring in the Recent tropical Indo-West Pacific fauna (e.g. 19 Philippine Islands species illustrated in colour by Fehse in Poppe 2008: pls. 175–179; nine species illustrated from northern Australia by Wilson 1993: 202–204, pl. 24) are all easily recognisable by their very tall, narrow shape, with a slightly swollen central region and a long, narrow, semitubular rostrum at each end, a smooth inner lip and a smooth or weakly dentate interior of the outer lip. The taxonomy of this group was revised extensively and many shells illustrated excellently in colour by Lorenz & Fehse (2009), who placed the species recorded from New Zealand in other genera. ‘Phenacovolva’ longirostrata was transferred to Calcarovula Cate, 1973 (Lorenz & Fehse 2009: 118), ‘P’. wakayamaensis was transferred to Kurodavolva Azuma, 1987 (the type and only included species; Lorenz & Fehse 2009: 120) and ‘P’. birostris was considered to be an unrecognisable nomen dubium. Smith (2010) recently illustrated nine species of Ovulidae observed alive at South Solitary Island in northern New South Wales, E Australia, demonstrating that even outside the tropics this family can be surprisingly diverse on gorgonians, soft corals and black corals. The distinction between Calcarovula, Kurodavolva, Takasagovolva Azuma, 1974 and Phenacovolva was originally based on radular characters (Azuma 1987). Their teleoconch shapes are similar but their subtle differences in shape seem to be reflected in the New Zealand fossils. We propose to include them in the most nearly similar genera illustrated by Lorenz & Fehse (2009), assuming that little has been lost from the ends of both species described here. Species referred to Pellasimnia Iredale, 1931 (Lorenz & Fehse 2009: 115, pls 155–160) resemble P. maxwelli n. sp. much more closely than Phenacovolva in their smaller size (9–37mm long) and in having short, relatively weakly tapered rostra, a slight, narrow, spiral swelling in the central region of the shell and a rather widely open anterior siphonal canal. It seems preferable to reflect this similarity by referring the Bridge Point fossil to Pellasimnia rather than to Phenacovolva. Another convincing character of Pellasimnia is its southern range – P. angasi (Reeve, 1865) occurs all around Australia, as well as throughout the central Pacific to Japan (Lorenz & Fehse 2009: 115), and P. maccoyi (Tenison Woods, 1878) occurs only in SE Australia, including Tasmania (Lorenz & Fehse 2009: 116). Pellasimnia seems to be the appropriate genus for P. maxwelli n. sp.

Following the same line of reasoning, we suggest that the most similar group in teleoconch shape to the following species is Prosimnia Schilder, 1925 (Lorenz & Fehse 2009: 63, pls 63–67). Prosimnia differs from Phenacovolva and Pellasimnia in the more cylindrical shape of the central inflated part of the last teleoconch whorl, in having a slightly protruding ridge around the shoulder, producing a weakly concave spire (posterior rostrum) outline in its short rostra and in its quite widely open anterior end of the aperture – particularly in Prosimnia piriei (Petuch, 1973 ) (Lorenz & Fehse 2009: pl. 67). Less extreme species such as Prosimnia korkosi Fehse, 2005 (Lorenz & Fehse 2009: pl. 66, figs. 7–8) would produce an internal mould closely resembling the Northland fossil. However, Prosimnia blackae n. sp. is more nearly cylindrical than most living species.

Schiaparelli et al. (2005) provided a molecular phylogeny of the Ovulidae that separated the many genera into four clades, despite their similar teleoconchs. Fehse (2007) and Lorenz & Fehse (2009) therefore recognised four subfamilies. Ovulidae provides a classic example of highly convergent evolution. As most elongate ovulids live and feed on narrow, elongate gorgonians, the evolution of a convergent shell form from disparate ancestors is quite feasible in this group. Fehse (2007: 122) pointed out that photographs of the living animals (many further photographs were included by Lorenz & Fehse 2009: pls A1–A374) demonstrate that the camouflage provided by colour patterns and papillae in living specimens is very different in species assigned to Aclyvolva, Hiatavolva and the genera similar to Phenacovolva, supporting the separation of these genera and subfamilies. Reijnen (2010) also commented on the camouflaging effect of the external animal features of small ovulids with very different teleoconchs at Halmahera, Indonesia. Pellasimnia belongs in subfamily Ovulinae, whereas Prosimnia belongs in subfamily Prionovolvinae.

Etymology. Again the name for the new species honours the memory of its collector, Phillip Maxwell.

Subfamily Prionovolvinae Fehse, 2007

Genus Prosimnia Schilder, 1925

Prosimnia Schilder 1925: 77. Type species (by original designation): Ovula semperi Weinkauff, 1881, Recent, Indo-West Pacific.

Prosimnia blackae n. sp. Figs. 4C–D

Simnia sp. Cernohorsky 1971: 127, fig. 19.

Type material. Holotype G7102, in collection AU6869, School of Geography, Geology and Environmental Science, Auckland University, from P08/f7569, grid ref. P08/004755, small disused quarry, N side of Mititai–Tauraroa Road 1 km E of junction with Inch Road, 1.8 km E of Maungaraho Trig., c. 5.5 km E of Mititai and 6 km NE of Tokatoka, between Kaipara Harbour and Dargaville, Northland (Otaian, Early Miocene, based on foraminiferal determinations by GH Scott, GNS). JA Grant-Mackie (University of Auckland pers. comm. 2009) reported that the matrix is matrix-supported pebbly siltstone, cemented with dark brown to black calcite, the pebbles being almost entirely irregular, rounded ones of Mahurangi Limestone, in clasts 1–3 cm in diameter. The breccia crops out within the throat of one of the Tokatoka volcanoes studied by Black (1966; 1967). The accompanying macrofauna includes the common molluscs Tucetona aucklandica (Powell, 1938) , Zeacolpus lawsi Marwick, 1971 , Polinices, and Amalda (Spinaspira) pakaurangiensis (Olson, 1956) , and the corals Oculina virgosa Squires, 1958 and Trancatoflabellum. Less common molluscs are species of Chama, Mesopeplum, Serripecten, Fasciculicardia, Tawera?, Dentalium, Laevidentalium, Ellatrivia, Chicoreus (Triplex) komiticus (Suter, 1917), Coluzea, Falsicolus kaiparaensis (Suter, 1917), Conus, Inquisitor and Bathytoma, along with the corals Cylindrophyllia minima Yabe & Eguchi, 1937 and Notocyathus conicus (Alcock, 1902) and diverse bryozoans. This fauna lived in shallow shelf seas in subtropical temperatures, apparently representing both a soft-substrate fauna and specimens transported from a nearby hard substrate, and the molluscs have much in common with those at Pakaurangi Point, Kaipara Harbour, not far to the south.

Distribution. Early Miocene, Northland.

Dimensions. H 11.0, D 3.4 mm.

Description. Holotype (only known specimen) an internal mould; exterior characters not visible. Shell small for genus, long and narrow (width 31% of height), an almost cylindrical rod with a near-cylindrical central, expanded section about half total length, contracting slightly but sharply to a narrower rostrum at each end. Last teleoconch whorl enclosing entire earlier shell. Both ends slightly incomplete, to an unknown degree. Aperture tall and narrow, extending entire length of shell; straight over central half of height, adapical section narrow and evenly slit-like, straight but inclined slightly to left; inner edge of outer lip expanded very slightly in towards inner lip in centre; aperture wider over anterior third of height, with weakly excavated columella and outer lip curved weakly to left. Cross-section evenly inflated except for dorsal slope behind outer lip, which is slightly flattened for last quarter-whorl, indicating a thickened, slightly flared lip on original shell; inner edge of thickening demarcated by low ridge on mould (shallow groove in original shell). Both lips completely smooth; outer lip evenly and smoothly enrolled, slightly wider at mid-point than above and below; shallow but obvious groove (ridge on original shell) extending from adapical end of central swelling to posterior end of shell, resulting from thickened former inner lip; shallowly concave mould of fossula present in posterior half of inner lip. Other internal characters of aperture not visible.

Remarks. Cernohorsky (1971) described and illustrated a similar specimen to Pellasimnia maxwelli n. sp. under the name ‘Simnia sp.’ from near Kaipara Harbour, Northland (Altonian–Otaian, Early Miocene), and this is now described as the holotype of Prosimnia blackae n. sp. Cernohorsky (1971) noted that ‘parts of the extremities are missing’, and it is likely that this specimen originally had slightly longer rostra; if the assignment to Prosimnia is correct, they possibly were little longer than in the preserved mould. Cernohorsky (1971) placed P. blackae n. sp. in Simnia Risso, 1826 because of the small size (length 11mm), the short rostra, a longitudinal keel on the dorsum and the smooth fossula, but none of these characters rules out a position in Prosimnia. Presumably what Cernohorsky meant by a ‘keel’ on the dorsum is the slight ridge margining the former callus inside the outer lip; this merely indicates that the lip was thickly callused. Prosimnia blackae n. sp. differs from Pellasimnia maxwelli n. sp. in its more evenly cylindrical central region, contracted more sharply to the bases of the rostra and producing a weakly concave rostral outline, whereas the central region of P. maxwelli n. sp. is shorter, less expanded and tapers more gently to the rostra which have straight outlines. Prosimnia blackae also has a more widely open anterior end than in P. maxwelli n. sp. Both species appear to have been very simple and smooth, with completely smooth edges to the lips, but no idea is gained of any original exterior sculpture from the internal mould of Prosimnia blackae n. sp.

These two species suggest that New Zealand gorgonians were inhabited as much by ovulids during warm Eocene to Miocene times as Northland and Tasmanian gorgonians are at present, and more New Zealand fossil species can be expected to be collected in future.

Etymology. The name for this new species again honours the name of the collector, Professor Philippa M. Black, University of Auckland, who collected it during her research on the Tokatoka district.

Superfamily Vanikoroidea Gray, 1840

Family Haloceratidae Warén & Bouchet, 1991

Genus Haloceras Dall, 1889

Separatista (Haloceras) Dall 1889: 277. Type species (by monotypy): Cithna cingulata Verrill, 1884, Recent, temperate N Atlantic, 36°–49°N, 1050–2685 m (Warén & Bouchet 1991: 138, figs. 53–55).

Solariella (Micropiliscus) Dall 1927: 130. Type species (by original designation): Solariella (Micropiliscus) constricta Dall, 1927 (= Cithna carinata Jeffreys, 1883 ), Recent, temperate E Atlantic, 27°–57°30′N and W Atlantic off Florida, 609–2075 m (Warén & Bouchet 1991: 137, figs. 58–61).

Haloceras maxwelli n. sp. Fig. 4A–B.

Type material. Holotype NMNZ M.284527, all data as for holotype of Neritina maxwellorum n. sp.: New Zealand fossil record no. J39/f7686, Waihao Greensand (Bortonian, Middle Eocene), left bank from 10–30 m upstream to 5–15 m downstream from Evans Crossing, Pareora River, South Canterbury; collected by PA Maxwell, 1992; grid reference J39/539437.

Distribution. Middle Eocene, South Canterbury.

Dimensions. H 3.7, D 2.7 mm.

Description. Shell of moderate size for genus, tall and narrow, height exceeding width (D 73% of H), with strongly convex whorls, deep suture and cancellate sculpture. Protoconch of 2.5 whorls; apical whorl low, rather flattened, with marginal keel but little other sculpture; second whorl becoming progressively taller, with two narrow spiral threads around periphery, remainder of surface sculptured with irregular, short, oblique to spirally elongate ridges, gradually developing axial sculpture of very narrow, thin, closely spaced, arcuate ridgelets, concave towards aperture, apex of curve at mid-height; last whorl taller, strongly and evenly convex, with curved axial costae more prominent; abruptly terminating at vertical arcuate group of closely spaced axial ridges where teleoconch spiral sculpture commences. Teleoconch of 3.0 whorls, sculptured with three prominent, narrow, widely and evenly spaced spiral cords around periphery, fourth equally prominent one emerging from suture on last whorl; sutural ramp bearing low, narrow, irregularly spaced spiral threads, increasing down teleoconch from 1 on first whorl to 4 on last whorl; base with 6 low, narrow, closely spaced spiral threads, innermost margining umbilicus. Spiral sculpture crossed by rather prominent, narrow, widely spaced axial ridges extending mainly over prominent spiral cords, crossing sutural ramp on early whorls but weakening over sutural ramp on last whorl; interspaces equal in width to 3–4 axial ridges and equal to spiral interspaces; forming evenly cancellate sculpture with low nodules at all intersections. Axial ridges continue to be weakly arcuate down entire teleoconch, weakly opisthocline (swinging forward to suture) over sutural ramp of last whorl, apparently collabral; outer lip almost straight but slightly incomplete. Umbilicus deep, narrow, 15% of diameter of base, with sharply angled outer margin, otherwise unsculptured. Aperture almost circular, slightly flattened across base; peristome continuous except where closely adherent to parietal area for a short segment; inner lip almost straight, lightly thickened along umbilical margin. Left end of basal lip meeting inner lip at sharp angle producing low, fasciole-like ridge along umbilical margin.

Remarks. To our knowledge, this is only the fourth fossil record of a species of Haloceratidae. The others are Haloceras carinata (Jeffreys, 1883), a species described from the living Mediterranean fauna and recorded fossil from S Italy (Di Geronimo & La Perna 1997), Haloceras contribulis Bertolaso & Palazzi (2000) from bathyal Pliocene rocks in Emilia, NW Italy and H. aff. contribulis, recorded from the Early Pliocene fauna at Estepona, S Spain, by Landau et al. (2004: 78). The present record is much the oldest one of the family.

Figure 4.  A–D, New Zealand fossil Ovulidae; A, B, Pellasimnia maxwelli n. sp., holotype, NMNZ M.284525, J42/f0126, Waiareka Volcanic Formation, Runangan (Late Eocene), Bridge Point, Kakanui, N Otago; C, D, Prosimnia blackae n. sp., holotype, SGGES, University of Auckland, G7102, AU6869, P08/f7569, Otaian (Early Miocene), Mititai-Tauraroa Road, 6 km NE of Tokatoka, Northland. E–F, Haloceras maxwelli n. sp., holotype, NMNZ M.284527, J39/f7686, Waihao Greensand, Bortonian (Middle Eocene), left bank Pareora River, Evan's Crossing, S Canterbury; SEM; E, whole shell; F, protoconch. 10 mm scale bar applies to A–D.

Warén & Bouchet (1991) described or redescribed all the species of Haloceratidae (in Haloceras Dall, 1889 and Zygoceras Warén & Bouchet, 1991). Haloceras maxwelli n. sp. is most similar to a group of a few relatively tall-spired species with 4 prominent, narrow spiral cords, 3 showing on spire whorls and the 4th issuing from the suture on the last whorl, and with prominent, narrow axial ridges forming small nodules at the sculptural intersections. These include H. japonica Okutani, 1964 (Warén & Bouchet 1991: 140, fig. 62; Japan–NE Pacific), which is markedly shorter than H. maxwelli n. sp. and has very weak axial sculpture; H. spinosa Warén & Bouchet (1991: 147, fig. 80; E Australia–New Caledonia), the most similar Recent species, but differing from H. maxwelli in its lower spire and in having the widest part of the whorl markedly higher on each whorl than in H. maxwelli n. sp.; and H. phaeocephala Warén & Bouchet (1991: 145, figs. 81–82; off New South Wales), which has a shorter spire than H. maxwelli n. sp. and has variable, weaker to more prominent axial sculpture, but with much smaller nodules at the sculptural intersections than in H. maxwelli n. sp. Italian and Spanish fossil specimens are similar to H. phaeocephala (Landau et al. 2004: 79) but have a shorter spire, fewer spiral cords and a distinctive protoconch. H. maxwelli n. sp. is the tallest species of Haloceras described to date. Species of Zygoceras differ from Haloceras in their markedly shorter protoconchs and narrower to closed umbilici, and the type species has a row of spines around the margin of the very low protoconch.

It is remarkable that the currently deepwater genus Haloceras occurs in the same fauna as Neritina maxwellorum n. sp., described above. We argue above that the presence of Neritina implies a shallow depth of deposition for Waihao Greensand at the Evans Crossing site, and this was evidently one of the shallowest-water recorded occurrences of Haloceras. Apparently it simply implies that this genus, like many others, has changed its ecology with time.

Etymology. Again the name of the new species honours the memory of Phillip Maxwell.

Clade Neogastropoda

Superfamily Buccinoidea Rafinesque, 1815

Family Fasciolariidae Gray, 1853

Genus Clavilithes Swainson, 1840

Clavella Swainson 1835: 21 (junior homonym of Clavella Oken, 1815).

Clavilithes Swainson 1840: 304 (as Clavilithes where defined (Swainson 1840: 304), but as Clavalithes on pp. 77, 94, 95, and index, p. 409). Type species (by subsequent designation, Herrmannsen 1846: 246): Fusus noae Chemnitz (non-binominal; that is, F. noae Holten, 1802) (Fig. 5C; Cossmann & Pissarro 1911: pl. 40, fig. 198–7; Le Renard & Pacaud 1995: 117), Eocene, England and Paris Basin, France (Snyder 1999: 3).

Cyrtulus Hinds 1843: 256. Type species (by monotypy): Cyrtulus serotinus Hinds, 1843, Recent, Marquesas Islands.

Turrispira Conrad 1866:19. Type species (by monotypy): Fusus salebrosus Conrad, 1834 (= Fusus protextus Conrad, 1833) , Middle Eocene, Gosport Sand, Claiborne Bluff, Monroe Co., SE USA (Harris 1893: 56, pl. 18, fig. 7; Palmer 1937: 357).

Clavellofusus Grabau 1904: 99. Type species (by original designation): Clavellofusus spiratus Grabau, 1904, Eocene, Paris Basin (Grabau 1904: 99, pl. 1, figs. 17, 20, 23, 26; pl. 18, fig. 4) (= Clavilithes parisiensis (Mayer-Eymar, 1877), Fig. 5D; Cossmann 1907: 262, C. spiratus=C. deformis Cossmann (1889: 177)=C. parisiensis).

Rhopalithes Grabau 1904: 135. Type species (by original designation): Fusus noae Lamarck, 1803 (that is, F. noae Holten 1802; Fig. 5C), Eocene, Paris Basin, France (Cossmann & Pissarro 1911: pl. 40, fig. 198–7; Le Renard & Pacaud 1995: 117).

Cosmolithes Grabau 1904: 142. Type species (by original designation): Fusus uniplicatus Lamarck, 1803, Eocene, Paris Basin, France (Cossmann & Pissarro 1911: pl. 41, fig. 198–12) (new synonym).

Chiralithes Olsson 1930:50. Type species (by original designation): Clavilithes (Chiralithes) cynosuris Olsson, 1930, Eocene, Chira shales, Peru (new synonym).

Perulithes Olsson 1930: 52. Type species (by original designation): Clavilithes peruvianus Woods, 1922 , Eocene, Peru (new synonym).

Austrolithes Finlay 1931: 14. Type species (by original designation): Fusus bulbodes Tate, 1888, Balcombian (middle Miocene), southern Australia (new synonym).

Remarks. Genera related to Clavilithes are included in family Fasciolariidae (Bouchet et al. 2005: 62, 255). Several authors from Mayer-Eymar (1877) to Cossmann (1901) considered Cyrtulus Hinds, 1843 to be a synonym of Clavilithes, that is, that Clavilithes is still living at the Marquesas Islands in the easternmost Indo-West Pacific. Snyder (2003: 186) seems to have regarded Cyrtulus as a genus distinct from Clavilithes, although this is not certain (Snyder 2003: 297). A broad concept of the genus Clavilithes is adopted here.

Figure 5.  Clavilithes species, all coated with MgO. A, Clavilithes philmaxwelli n. sp., holotype, NMNZ M.284340, Kauru Formation, Mangaorapan (Early Eocene), right bank Otaio River c. 300 m downstream from Otaio Gorge Bridge, S Canterbury (= GS5618, J39/f8539). B, Clavilithes rugosus (Lamarck), immature specimen, WM5912, Calcaire Grossier, Lutetian (Middle Eocene), Paris Basin, France. C, Clavilithes noae (Holten), type species of Clavilithes Swainson, 1840 and of Rhopalithes Grabau, 1904, small specimen; WM5832, Calcaire Grossier, Lutetian (Middle Eocene), Paris Basin, France. D, Clavilithes parisiensis (Mayer-Eymar), type species of Clavellofusus Grabau, 1904, small specimen; WM5831, Calcaire Grossier, Lutetian (Middle Eocene), Paris Basin, France. Left scale bar applies to A and B; right scale bar applies to C and D.

The generic name was spelled Clavalithes by Swainson (1840: 77, 94, 95 and in the index, p. 409). The index refers to all his other usages in this work, including where it was spelled ‘Clavilithes’ (p. 304). Evidently Clavalithes was his intended spelling, and Clavilithes was an error. The first reviser deliberately to choose one of these spellings was Wrigley (1927: 224, footnote 2), who chose Clavilithes on grammatical grounds. Gary Rosenberg (Academy of Natural Sciences, Philadelphia, pers. comm.) confirmed that under ICZN Article 67.7, Herrmannsen's (1847: 246) type species designation for Clavilithes is valid, as was concluded by Snyder (1999).

Several generic names proposed by Grabau (1904) and Olsson (1930) that seem in our opinion to be synonyms intergrading with Clavilithes are listed in the generic synonymy. Pritchard (1904: 320–324) recognised that Tate (1888) had confused two species under the name Fusus bulbodes. Finlay (1931) designated the type species of Austrolithes as Fusus bulbodes ‘as restricted by Pritchard’, rather than Clavella platystropha Pritchard, 1904. The catalogue by Darragh (1970) (where original references are provided) includes four species referred to Austrolithes: A. bulbodes, Middle Miocene, near Melbourne; A. incompositus (Tate, 1888), Eocene, Aldinga, South Australia; A. platystropha, Middle Miocene, Muddy Creek; and A. tateanus (Tenison Woods, 1877), Early Miocene, Fossil Bluff, northern Tasmania.

Like Ampullinidae related to Globularia, Clavilithes is one of the classical Paris Basin Eocene genera that has never been reported from New Zealand previously, although it occurs in Australian Late Eocene–Middle Miocene rocks. The genus is recorded widely around the world. Grabau (1904) revised Clavilithes species in Cenozoic rocks of France, England, Germany, Italy and the USA, but divided it into several genera and subgenera (not all of which were accepted by Cossmann & Pissarro 1911). Cossmann (1901: 20–21) listed numerous other species from the Palaeocene of Denmark, the Eocene of England, France, Italy, Switzerland, USA and Australia, the Oligocene of Germany and Italy, the Miocene of France and Italy, the Pliocene of Java and the living species C. serotinus. Wrigley (1927) described and illustrated 19 English species. Wenz (1943: 1252) included numerous further species from North Africa, India, the Philippine Islands, the West Indies and South America. Palmer & Brann (1966: 583–588) listed 20 species occurring in Eocene rocks of the SE USA. Le Renard & Pacaud (1995: 117) listed 27 species of Clavilithes (sensu lato) occurring in the Paris Basin. Snyder (2003: 295–298) listed 163 species names in his ‘Clavilithes group’, including all the genera considered here to be at least closely related to Clavilithes. Finlay (1931: 14) differentiated the genus Austrolithes from Clavilithes solely by developmental characters of the protoconch. Most Australian species had direct development, passing through their early life-cycle within the female's brood pouch and being released as small benthic adults bearing a large, only partly calcified protoconch. Some Paris Basin species have smaller protoconchs and apparently had lecithotrophic development with a demersal larval stage. Some other Paris Basin species, including the type species, however, had protoconchs similar to but rather smaller than the Australian species, e.g. C. longaevus (Solander in Brander, 1766 ) and C. parisiensis (Mayer-Eymar, 1877; Cossmann & Pissarro 1911: pl. 40, figs. 198-1–198-2). Clavilithes is apparently merely among the many taxa that adopted direct development after arriving in Australia. The specimen collected by Phillip Maxwell is smaller and narrower than typical Paris Basin species of Clavilithes and lacks a protoconch. Nevertheless, it clearly belongs in the Clavilithes generic complex, at least in a broad sense.

Clavilithes philmaxwelli n. sp. Fig. 5A.

Type material. Holotype NMNZ M.284340, cemented shellbeds (Kauru Formation), Mangaorapan (Early Eocene), Otaio River, South Canterbury, right bank c. 300 m downstream from Otaio Gorge Bridge and 40 m downstream from top of lower coal bed, grid reference J39/454297; collected lying loose on the river bank by PA Maxwell, c. 2002–2004; equivalent to GNS Science locality GS5618, NZ fossil record no. J39/f8539, the locality for the holotype of Globularia maxwelli n. sp. and of the fauna described by Marwick (1960).

Distribution. Early Eocene, South Canterbury.

Dimensions. H 56.6, D 18.4 mm (original dimensions, slightly incomplete, canal tip and protoconch missing, outer lip slightly incomplete, laterally compressed; now still more incomplete, damaged during photography; originally c. 65×20 mm).

Description. Shell small for genus (immature?), tall and narrow, with moderately tall, stepped spire and long, narrow, straight anterior siphonal canal lacking all sign of a fasciole, continuing straight in line with base of last whorl after basal contraction. Protoconch missing. Teleoconch of six whorls, with tall, thin, obvious, wavy subsutural fold, deeply concave sutural ramp, strongly, evenly and narrowly convex spire whorls below ramp, sharply contracted base as on all Clavilithes species and well-developed, fine spiral sculpture. Major sculpture of prominent, evenly rounded axial folds down entire teleoconch, extending from sutural ramp to lower suture on spire whorls, stopping at basal contraction on last whorl; alternating in position between whorls to some extent down spire to produce wavy subsutural fold; eight axial folds per whorl on all whorls. Entire exterior crossed by low, narrow, widely spaced spiral threads, one slightly wider and more prominent alternating with one slightly lower and narrower, each secondary interspace slightly wider than one thread; c. 16 well-preserved threads on penultimate whorl, slightly abraded elsewhere; lower and more closely spaced on anterior siphonal canal. Aperture small for shell size, tall and narrowly oval, with thick, smooth, straight inner lip, completely unexcavated columella, left edge of lip free for entire height of aperture and canal; wide but low callus pad on parietal area; faint sign of one very weak, low columellar ridge near base of columella; outer lip thick, interior smooth, but outer edge broken back slightly.

Remarks. Clavilithes philmaxwelli n. sp. differs from the Australian species named by Tate (1888) and Pritchard (1904) mainly in being much smaller and narrower. Tate's (1888: pl. 7, fig. 8) original illustration of C. bulbodes also shows an immature specimen, but it clearly differs from C. philmaxwelli n. sp. in its taller and narrower shape, its weaker subsutural fold, its slightly more prominent, more widely spaced spiral sculpture and in lacking axial folds altogether. Tate's (1888: pl. 13, fig. 5) illustration of C. tateanus from Fossil Bluff, N Tasmania (Batesfordian, early Miocene) shows a much more typical specimen, closely resembling Paris Basin Eocene fossils with an appressed suture and axial folds on early spire whorls fading out down the teleoconch to result in a smooth last whorl. Clavilithes incompositus (Tate 1888: 137, pl. 3, fig. 9) was based on a small juvenile (only 27 mm high) resembling Tate's drawing of C. bulbodes in most characters, but with six large, hemispherical nodules per whorl. It also lacks a subsutural fold, and so looks very different from C. philmaxwelli n. sp. Pritchard (1904: 18, figs. 2–5) illustrated adult and juvenile specimens of both C. bulbodes (figs. 2–3) and C. platystropha (figs. 4–5). He showed that C. platystropha is again a more typical species resembling the smooth Paris Basin Eocene species such as C. parisiensis with almost straight whorl outlines, almost no axial sculpture even on early spire whorls and only a little fine spiral sculpture early on the spire. In contrast, adult specimens of C. bulbodes have a more evenly rounded whorl profile, a weakly concave sutural ramp and a little fine spiral sculpture on the adapical half of the teleoconch, intermediate between the characters of C. philmaxwelli n. sp. and C. platystropha. The most nearly similar Paris Basin Eocene species is C. rugosus (Lamarck, 1803) (Fig. 5B), which has similar axial folds to those of C. philmaxwelli n. sp. but differs from it in having narrower and more widely spaced axial folds, a lower subsutural fold, more prominent spiral sculpture and a less sharply contracted base. It also has numerous fine, closely spaced axial threads that are not present on most other Clavilithes species, including C. philmaxwelli n. sp. C. intermedius Wrigley (1917: 228, pl. 34, fig. 13; upper Bracklesham Beds, Brook, England) is also very similar in shape and sculpture, although with almost no subsutural fold. Wrigley (1917: 228) made the point that C. intermedius is very similar to such species as C. (Rhopalithes) loiseli Chédeville, 1904 and C. (Cosmolithes) lemarchandi Cossmann, 1907 in all characters except for its complete lack of columellar plaits, again throwing doubt on plaits as a generic character. Clavilithes cynosuris (Olsson 1930: 51, pl. 9, figs. 2–6; Eocene, Chira ‘shales’ at Yasila, Peru) has a very similar profile including the lengths of the spire and anterior siphonal canal, a similar narrow but prominent subsutural fold and similar, evenly convex whorl outlines to those of C. philmaxwelli n. sp. In addition, it has eight very similar axial folds per whorl, but has finer and more closely spaced spiral sculpture than C. philmaxwelli n. sp. The illustrated paratype of C. cynosuris is particularly closely similar to the holotype of C. philmaxwelli n. sp. C. elongatus Wrigley (1917: 229, pl. 34, figs. 16–17) is also similar to both C. philmaxwelli n. sp. and C. cynosuris, differing in its weaker spiral sculpture but more prominent, sharp subsutural fold, and is intermediate between typical Paris Basin Clavilithes species and the more strongly sculptured species such as C. rugosus.

As only one specimen of Clavilithes philmaxwelli n. sp. has been collected the size range and whether the holotype is adult are not known, although the type material of C. cynosuris has the same size range (H 40–59 mm) estimated by Olsson (1930; 80–90 mm). Most specimens from the Otaio Gorge shellbed are considerably smaller than the holotype of C. philmaxwelli n. sp., but this apparently results from post-mortem size sorting rather than reflecting the original composition of the fauna. The holotype of C. philmaxwelli n. sp. seems likely to be immature.

Etymology. This new species is again named in honour of its collector, Phillip Maxwell.

Temperature significance

The main significance of the recognition of the present species of Neritina, Ovulidae and Clavilithes in New Zealand lies in the warm Eocene–Miocene sea temperatures they indicate. The Early Eocene occurrence of Globularia at Otaio Gorge is not unexpected in view of the wide distribution of Ampullinidae in world early Palaeogene molluscan faunas, and of the warm sea temperatures prevailing at this time (Pearson et al. 2007). It is now suggested that sea temperatures in the high-latitude Southwest Pacific reached 30°C during Eocene time (Hollis et al. 2009). The Mangaorapan Otaio Gorge fauna lived not long after the Palaeocene–Eocene Thermal Maximum (which defines the base of the Waipawan Stage, the underlying stage in the New Zealand succession). This brief but extreme temperature spike has been studied extensively (e.g. Thomas et al. 1999; Crouch et al. 2001; Zachos et al. 2003; 2006; Tripati & Elderfield 2004; Nunes & Norris 2006). Beu & Maxwell (1990): 96) pointed out the occurrence of at least four taxa of cowries (Cypraeidae and Ovulidae; including Bernaya chathamensis Cernohorsky 1971: 117, Archicypraea eripnides Darragh 2002: 357; Dolin & Pacaud 2009: 279; and two unnamed taxa) in the Early Eocene Red Bluff Tuff of the Chatham Islands as evidence that this was the warmest time recorded by macrofossils in the New Zealand region. Globularia and Clavilithes were members of the widely distributed, characteristic Palaeogene molluscan fauna that was greatly reduced before Neogene time (Beu 2009: 201).

The occurrence of Clavilithes at Otaio Gorge is more unexpected, as this genus of large, obvious, fusiform gastropods had not been reported in New Zealand previously despite 150 years of collecting and despite an Eocene–Middle Miocene record in southern Australia. This group of Fasciolariidae is represented in the living fauna only by the restricted Marquesas Islands species Clavilithes serotinus (Grabau 1904: 97, fig. 13, 14; Abbott & Dance 1982: 183, bottom right fig.; Bouchet 1998: 2 figs on cover; Robin 2008: pl. 224, fig. 9). C. serotinus is similar to extreme fossil species such as C. maximus (Deshayes, 1835) (Cossmann & Pissarro 1911: pl. 40, fig. 198-3). In our opinion C. serotinus is a living species of Clavilithes, which was largely a tropical genus. It seems likely that New Zealand lay outside the range of the Clavilithes, except during the warmest period of Early Eocene time. The occurrence of the tropical to warm-temperate ovulid genus Pellasimnia at Bridge Point, Kakanui also indicates that temperatures in the south-eastern South Island were significantly warmer during Late Eocene time than we suspected previously. The fauna at Bridge Point and nearby Late Eocene localities has long been known to include such warm-water taxa as Quadrilatera, Bolma, Ficus, Colubraria and Gemmula (Beu & Maxwell 1990: 114) and a thin bed rich in nautiloids crops out at Bridge Point, but nothing as warm-water as Pellasimnia has been reported from there previously. However, Haloceras is a curiosity, only the fourth fossil record of a rare mostly deepwater family, rather than a temperature indicator.

The most unexpected new record is the new genus and species of Naticidae, Maxwellinatica phillipi, at Elephant Hill Stream in Mount Harris Formation (Altonian, late Early Miocene). Initially we identified this as a species of Cernina (Ampullinidae). The one living species of Ampullinidae, the ‘living fossil’ (Kase & Ishikawa 2003) Cernina fluctuata, is restricted to the eastern Philippine Islands at present (Hollman in Poppe 2008: 482). C. fluctuata was more widespread during the Miocene–Pliocene time than it is now, occurring from East Africa (Cox 1930b) and India (JdeC Sowerby 1840; Dey 1961; Harzhauser et al. 2009) to Sabah (Cox 1948), Borneo (Beets 1941) and Java (Pannekoek 1936). Its range has evidently contracted as temperatures fell during late Neogene time. Nevertheless, there is no evidence of such a warm-water genus in even Australian Miocene rocks, and this seemed an extraordinary record of a tropical genus in the Miocene of New Zealand. Recognition that it is actually a genus of Naticidae removes the apparent anomaly.

Coeval sea temperatures in Northland and in the Clifden section, Southland, have long been known to have been the warmest recorded by molluscs in New Zealand Neogene rocks. A remarkable fauna of diverse subtropical to marginally tropical molluscs is recorded, such as Spondylus, Cypraea (one common species), Eudolium, Chicoreus (Triplex), Discotectonica and Cryptoplax (Beu & Maxwell 1990: 169–173), and fragments of tropical reef corals are common at some Northland localities (Squires 1958). The addition of a species of Prosimnia to this fauna is not surprising, as the genus ranges as far south as Tasmania at present, and species of the related genera Calcarovula and Kurodavolva live in northern New Zealand. The Early Miocene molluscan fauna of North Otago–South Canterbury indicates that sea temperatures were also warmer there than they are today, although considerably cooler than they were in Southland and Northland. Recorded genera include Austrohinnites, large Nemocardium, Clavagella, Cantharus (Zeapollia), Exilia, Pterynotus, Architectonica, diverse Eratoidae, several small species of Conus, one species of Ficus and the large cancellariid Maorivetia (Beu & Maxwell 1990: 165–168). However, no strictly tropical taxa such as Cypraeidae and Ovulidae occur in North Otago–South Canterbury. Reconstructions of the New Zealand region during Early Miocene time (King et al. 1999; King 2000) make the reason for this clear: the present eastern South Island faced southwards towards Antarctica at that time, whereas Southland and Northland both faced northwards towards the tropical Pacific.

Acknowledgements

This study was funded by the New Zealand Foundation for Research, Science and Technology through Backbone Fund Contract CO5XO412 (National Palaeontology Collection), and is dedicated to the memory of Phillip Maxwell, collector of almost all the material we include here. Jack Grant-Mackie (SGGES, University of Auckland) generously provided the type material of Prosimnia blackae n. sp. and supplied all the information cited here; it was loaned by Neville Hudson, SGGES collection curator. Guido Poppe (Conchology Inc., Mactan, Cebu) generously presented GNS with two specimens of Cernina fluctuata. We are grateful to Tom Darragh (Museum Victoria, Melbourne) for comments on the manuscript. Photography and SEM micrographs are by Marianna Terezow (GNS) and the figures were prepared by Philip Carthew (GNS).