Diversity and biogeography of the little known deep-sea barnacles of the genus Waikalasma Buckeridge, 1983 (Balanomorpha: Chionelasmatoidea) in the Southwest Pacific, with description of a new species

ABSTRACT

Due to the extreme scarcity of specimens, little is known about the biodiversity and biogeography of the barnacles of the genus Waikalasma Buckeridge, 1983 (Thoracica: Waikalasmatidae Ross and Newman, 2001), which inhabit the deep sea of the Southwest Pacific. Previous studies reported only a single living species, W. boucheti Buckeridge, 1996, from Vanuatu. In the present study, the collections by French deep-sea expeditions off New Caledonia (NORFOLK 1 & 2, EBISCO, SMIB 2, SMIB 4, SMIB 8, BIOCAL, MUSORSTOM 6, MUSORSTOM 4, MUSORSTOM 5, BATHUS 2), the Solomon Islands (SALOMON 1), Vanuatu (BOA1) and Papua New Guinea (BIOPAPUA) yielded specimens of Waikalasma species from 500 to 800 m depth. From molecular (DNA barcode region cytochrome c oxidase subunit I (COI) and 12S gene) and morphological analysis, a new species Waikalasma dianajonesae sp. nov., and W. boucheti were identified. From molecular phylogenetic analysis, sequence divergence in the DNA barcode region between W. dianajonesae sp nov. and W. boucheti reached > 10%. Waikalasma dianajonesae sp. nov. differs from W. boucheti in the number and size of imbricating plates on the shell and the shape of the tergum. Waikalasma dianajonesae sp. nov. and W. boucheti exhibit sympatric biogeographical distributions in the Southwest Pacific. Waikalasma dianajonesae was found in the waters of Papua New Guinea and Solomon Island, whilst W. boucheti was collected from Papua New Guinea, Vanuatu and New Caledonia waters.

http://zoobank.org/urn:lsid:zoobank.org:pub:713013C7-677A-478F-B5DF-FD4690A7C6A9

KEYWORDS:

• Deep-sea
• Waikalasma
• biogeography
• South Pacific

Acknowledgements

The authors would like to thank Diana Jones (Western Australian Museum) for her comments on the manuscript. The specimens studied were collected during the deep-sea cruises and expeditions of the Tropical Deep-Sea Benthos Program (MNHN, IRD) off New Caledonia (NORFOLK 2, EXBODI), the Solomon Islands (SALOMON 1), Vanuatu (MUSORSTOM 8) and Papua New Guinea (BIOPAPUA). The authors would like to thank the principal investigators (PIs) of the Tropical Deep-Sea Benthos programme cruises: B. Richer de Forges, P. Bouchet, S. Samadi and Corbari L. Special thanks are also given to the crew of RV ALIS.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study has been supported by the ANR project France-Taiwan DeepEvo (PI: S. Samadi and W-J Chen). This project is also supported by a Taiwan-France collaboration grant from MOST, Taiwan Ministry of Science and Technology [NSC-102-2923-B-002 −001 -MY3].