An integrated approach to explore the monophyletic status of the cosmopolitan genus Hexabathynella (Crustacea, Bathynellacea, Parabathynellidae): two new species from Rottnest Island (Wadjemup), Western Australia

Abstract

The Hexabathynella genus is the only genus of the family Parabathynellidae that has supposedly a worldwide distribution. Currently, there are 23 species described from five continents. In Australia, only two Hexabathynella species have been named from the eastern coast, however, a few taxa have been collected from Western Australia during stygofauna sampling as part of research studies and legislated compliance-based Environmental Impact Assessments. One of these areas includes Rottnest Island (Wadjemup), located offshore of Perth in Western Australia. Unpublished data on stygofaunal communities inhabiting the groundwater of the island refer to discrete abundances of copepods and syncarids, but no species description has been carried out. In this study, we describe two new species: Hexabathynella quokkai and H. bisetosa, expanding the characterization of the subterranean aquatic community at Rottnest Island, and using a COI, 18S and 12S sequence-based phylogeny to test the monophyletic status of the genus. Our findings shed new light on the distribution of Hexabathynella and its reported cosmopolitan distribution.

http://zoobank.org/urn:lsid:zoobank.org:act:03634EAD-4D27-4446-AE53-4248303D5020

http://zoobank.org/urn:lsid:zoobank.org:act:1B325914-90FD-471E-AC03-20741C7C925A

Key words:

• Bathynellacea
• distribution
• DNA
• Hexabathynella
• multigene phylogeny
• new species
• stygofauna

Acknowledgements

We wish to acknowledge the Whadjuk Noongar people, the traditional custodians of Wadjemup (Rottnest Island). We pay respect to their Elders past, present and emerging, and their long and continuing connection to the land, waters and culture of the island. We also acknowledge the Whadjuk Noongar people as the Traditional Owners of the Country on which the Western Australian Museum and Curtin University are sited. We would like to acknowledge Biologic Environmental Survey, South Australian Museum, Curtin University (School of Molecular and Life Science and School of Earth and Planetary Science), Edith Cowan University and the Western Australian Museum for funding. We would also like to thank Dr Bill Humphreys, Biologic Environmental Survey, and the Western Australian Museum for their technical support. We also acknowledge the Western Australia Department of Biodiversity, Conservation and Attractions for sampling permits. We acknowledge the Rottnest Island Authority for logistical assistance. Special thanks to the efficient and motivated volunteer Diego Armando Rubiano Morales for his help during the field trip.

Disclosure statement

During the preparation of this paper Dr Perina was employed by Biologic Environmental Survey Pty Ltd and Curtin University.

Supplemental Material

Supplemental material for this article can be accessed here: https://doi.org/10.1080/14772000.2022.2151662.

Associate Editor: Dr Xikun Song

Additional information

Funding

This work was supported by project [PID2019-110243GB-100] by the MICINN/FEDER, Biologic Environmental Survey, South Australian Museum, Curtin University (School of Molecular and Life Science and School of Earth and Planetary Science), Edith Cowan University.