Marine Mollusca of oxygen isotope stages of the last 2 million years in New Zealand. Part 2. Biostratigraphically useful and new Pliocene to recent bivalves

Abstract

New Zealand Plio‐Pleistocene bivalves revised: Limopsis, oysters, Pecten, Mactra (Maorimactra), Oxyperas, Lutraria, Austrovenus, Barnea, Myadora. Recent Indo‐West Pacific Lutraria species are reviewed; the Red Sea‐East African species L. (Lutraria) turneri Jousseaume resembles L. grandis (Hutton) (adopted in place of the junior homonym L. solida Hutton). Six new species proposed: Saccella maxwelli (Nukumaruan‐Recent; known previously as S. bellula (A. Adams)); Limopsis turnbulli (Castlecliffian, OIS 15–20, SW Fiordland); Mactra (Maorimactra) marwicki (late Nu‐kumaruan); M. (Maorimactra) carteri (early Castlecliffian, OIS 45?‐19); Paphies delta (early Castlecliffian, OIS 31?‐17); Myadora fortecosta (Kapitean‐Opoitian). Further Indo‐West Pacific warm‐water migrants to New Zealand: Chama ruderalis Lamarck (Kapitean‐Nukumaruan; = C. huttoni Hector, = C. pittensis Marwick); Lutraria (Psam‐mophila) vellai (Beu) (late Nukumaruan); probably the two New Zealand late Neogene Ctenoides species. Further temperate migrant from the Atlantic: Lutraria (Lutraria) grandis. New synonymy: Xenostrobus Wilson = Limnoperna Rochebrune; Pecten no‐vaezelandiae (Reeve) = all other New Zealand Pecten names; Serratina eugonia (Suter) = S. charlottae (E. A. Smith); Oxyperas komakoensis (Carter) = O. elongata (Quoy & Gaimard); Austrovenus stutchburyi (Wood) varies clinally over New Zealand, = A. aucklandica Powell, = A. crassitesta Finlay; Dosinia (Austrodosinia) horrida Marwick = D. anus (Philippi) (Nukumaruan‐Recent); Panopea wanganuica Powell = P. smithae Powell (Nukumaruan‐Recent); Myadora stephaniae Carter = M. waitotarana Powell (Waipipian‐Nukumaruan). Distinctive bivalves extinct at the end of Nukumaruan time: Glycymeris shrimptoni Marwick, Patro undatus (Hutton), Lutraria (Lutraria) grandis, L. (Psammophila) vellai, Paphies crassiformis (Marshall & Murdoch), Eumarcia plana Marwick, Dosinia (Raina) nukumaruensis Marwick, Myadora waitotarana. Ennucula Iredale is used for Cenozoic and Recent Nuculominae; the application of Leionucula Quenstedt is unclear. Saccostrea glomerata (Gould) is used in place of S. circumsuta (Gould). Protothaca crassicosta (Deshayes) (formerly Haweran‐Recent) is recorded from Opoitian rocks. Pecten novaezelandiae appeared below Potaka Tephra (1.0 Ma) during OIS 29 or earlier in eastern New Zealand, but just above the Brunhes‐Matuyama transition (0.78 Ma, early OIS 19) in Wanganui Basin. Oxyperas elongata and Barnea similis (Gray) changed anagenetically through late Miocene‐Pleistocene time; earlier forms are conspecific with Recent ones. Tawera Marwick is restored as a genus. Purpurocardia Maxwell is compared with Glans Megerle von Muhlfeld and Glyptoactis Stewart, and all are retained. Limnoperna huttoni (Suter) became extinct during OIS 13, Barytellina crassidens Marwick during OIS 9 or younger. Pholadidea tridens (Gray) (OIS 23 & 5a) and Ostreola virescens (Angas, 1868) are recorded fossil.

Keywords:

• biostratigraphy
• Bivalvia
• Castlecliffian
• dispersal
• evolution
• Haweran
• Holocene
• Mollusca
• new species
• New Zealand
• Nukumaruan
• oxygen isotope stages
• Pleistocene
• Pliocene
• taxonomy
• time scale
• Wanganui Basin

Notes

GNS Science, PO Box 30368, Lower Hutt 5040, New Zealand. [email protected]