Two new species of Atopobathynella (Parabathynellidae, Bathynellacea) from the Pilbara region, Australia

Abstract

Fifteen species of the Gondwanan genus Atopobathynella have been described so far from four countries. The position of the genus within the family Parabathynellidae and its species relationships are controversial due to the different characters and species considered by different authors, however most of the phylogenetic reconstructions are based solely on morphological characters. In the past few decades, the arid zones of Western Australia, including the Pilbara region, have been recognized as a hotspot for subterranean fauna. Material is constantly collected to produce Environmental Impact Assessments to protect and manage the subterranean environment. In 2009 the Cleaverville Iron Formation, in the Pilbara region, northern Western Australia, was proposed to be mined, therefore subterranean fauna sampling was conducted as per legislation. Preliminary molecular studies of stygofauna identified two distinct Parabathynellidae lineages from two ridges, however no morphological descriptions were carried out at that time. In this study, we describe two new species from Yarrie and Callawa ridges, respectively: Atopobathynella yarriensis sp. nov. and A. degreyensis sp. nov.. The new species show differences in male antennal organ, ventral tooth of mandible, number of teeth on distal endite of maxillula, absence or presence of epipod of thoracopod I, number of setae on article 4 of thoracopod II, length of distal external seta of exopod of all thoracopods, outer lobe of male thoracopod VIII, number of spines on uropodal sympod and furcal rami, length of the external dorsal plumose seta of the furcal rami. Additionally, we integrated the morphological data with sequences of three genetic loci, Cytochrome Oxidase c Subunit I (COI), 12S rRNA (12S), and nuclear 18S rRNA (18S), calculating p-distances and constructing a multigene molecular phylogeny to support morphology, and explore the monophyletic status of the genus and the relationship amongst its species. The two new species were well supported in our phylogeny, however they appear distantly related.

http://zoobank.org/urn:lsid:zoobank.org:act:2D8DA822-6C08-45B5-B707-6F63A1B69DE2

Key words:

• Bathynellacea
• distribution
• DNA
• iron formation
• multigene phylogeny
• new species
• stygofauna

Acknowledgements

We acknowledge the Whadjuk Noongar people as the Traditional Owners of the Country on which the Western Australian Museum and Curtin University are sited.

Disclosure statement

During the preparation of this paper Dr Perina was employed by Biologic Environmental Survey Pty Ltd, between 2008 and 2014 Dr Perina worked for Subterranean Ecology Pty Ltd.

Supplemental material

Supplemental material S1: Atopobathynella species list with type locality and habitat notes. Below the line: list of Atopobathynella taxa with genetic data available.

Supplemental material S2: List of taxa included in the molecular phylogeny with localities, voucher numbers and GenBank accession numbers.

Supplemental material S3: COI alignment of 15 sequences trimmed at 585 bp used to calculate the uncorrected p-distance between the two new species. Fasta file.

Supplemental material S4: Concatenate COI-18S IQtree. Pdf file.

Supplemental material S5: Concatenate COI-18S MrBayes tree. Pdf file.

Supplemental material S6: Concatenate COI-18S RAxML tree. Pdf file.

Supplemental material S7: Atopobathynella yarriensis and Atopobathynella degreyensis type series and additional material studied.

Supplemental material S8: Taxonomic characters of Atopobathynella, Schminke, 1973 species. 1. Atopobathynella valdiviana (Noodt, 1965); 2. A. compagana Schminke, 1973; 3. A. chelifera Schminke, 1973; 4. A. hospitalis Schminke, 1973; 5. A. wattsi Cho, Humphreys & Lee, 2006; 6. A. hinzeae Cho, Humphreys & Lee, 2006; 7. A. glenayleensis Cho, Humphreys & Lee, 2006; 8. A. readi Cho, Humphreys & Lee, 2006; 9. A. gascoyneensis Cho, Humphreys & Lee, 2006; 10. A. schminkei Cho, Humphreys & Lee, 2006; 11. A. yarriesnsis sp. nov. Perina & Camacho. 12. A. degreyensis sp. nov. Perina & Camacho; 13. A. operculata Ranga Reddy et al., 2008; 14. A. paraoperculata Ranga Reddy & Totakura, 2015; 15. A. indica Bandari et al., 2017; 16. A. nelloreensis Bandari et al., 2017; 17. A. inopinata Bandari et al., 2017. Abbreviations: A = absent; AI = antennule; AII = antenna; Art = article B = barbed; Endp = endopod; Exp = exopod; Frc = furca; H = homonomous; IH = non-homonomous; L = large; M = medium size; Md = mandible; Mdf = modified; MxI = maxillula; MxII = maxilla; N = not; NPr = not pronounced; NExc = does not exceed; P = plumose; Pr = pronounced; Rect = rectangular; S = smooth; Sm = small; Sh = short; Sml = similar; Spr = separated; SQua = subquadrate; Symp = sympod; ThI = thoracopod I; ThVIII = thoracopod VIII; Trg = triangular; Urp = uropod; W = wrinkled; Y = yes. As Bandari et al. (2017): (I) = antennal organ type I, without protrusion with one or two setae; (II) = antennal organ type II with protrusion with or without seta; Type III: antennal organ with protrusion and a digitiform process, without seta. *Dagger-like structure of the endopod not counted.

Associate Editor: Dr Xikun Song

Additional information

Funding

This work was supported by: Australian Biological Research Study grant 4- G03Y8RR, Australian Government’s National Taxonomy Research Grant Program (NTRGP); project [PID2019-110243GB-100] by the MICINN/FEDER, Biologic Environmental Survey, Rio Tinto. MTG was supported by Australian Research Council Linkage Project Grant LP190100555 (linkage partners: Rio Tinto, BHP, Chevron, South Australian Museum, Western Australian Museum, Department of Biodiversity, Conservation and Attractions, Department for Water and Environmental Regulation, Western Australian Biodiversity Science Institute)