A new genus and species of fish parasitic cymothoid isopod (Crustacea) from Indian waters, with a key to the branchial-attaching cymothoid genera

ABSTRACT

Brucethoa bharata gen. et sp. nov. is described from the host fish Glossanodon macrocephalus Bineesh and Endo, 2019 (Argentinidae), at depths of 300–600 metres from the south-west coast of India. This monotypic genus is characterised by a head weakly immersed in pereonite 1, dorsum strongly vaulted, pereonites 6 and 7 with posterolateral margin expanded and coxae not visible in dorsal view, relatively wide pleon, pleonite ventrolateral margins produced with lateral gaps evident, both antennae slender, with antennula slightly longer than antenna, and large pleopod rami that extend laterally well beyond the pleotelson margins. Ovigerous females were found in the branchial cavity of the hosts and have proximally thickened oostegites with the posterior marsupium partly enclosed by two sub-rectangular fleshy lobes. All life stages of the new species are described [including females (ovigerous and non-ovigerous), male, transitional and larvae (premanca and manca)]. The species is currently known only from the type locality and the type host. A revised key to the marine branchial cymothoid genera of the world is provided.

Publication LSID: lsid:http://zoobank.org:pub:85E54167-072A-4513-B527-20FFD0F75CCA

KEYWORDS:

• Marine fish parasite
• branchial cavity
• cymothoidae
• life stages
• new genus
• Indian Ocean
• Glossanodon macrocephalus

Acknowledgements

The authors acknowledge the DS Kothari Post-Doctoral Fellowship of University Grants Commission, New Delhi (No. F.4-2/2006 (BSR)/BL/16-17/0401; dated: 28 August 2017) awarded to PTA. We extend our sincere thanks to Dr Niel L. Bruce, for his significant contribution to this manuscript, especially fixing the generic characters/revision/suggestions/discussions for the improvement of the MS. This work was in part supported by the National Research Foundation (NRF) of South Africa (NRF Grant Nos 120240 and 120403; KA Hadfield, PI). Opinions, findings, conclusions and recommendations expressed in this publication are that of the authors, and the NRF accepts no liability in this regard. This is contribution number 471 from the North-West University–Water Research Group.

Disclosure statement

No potential conflict of interest was reported by the authors.

Ethics approval: The specimen is not under the listed category of experimental animals which need ethics approval.

Availability of data and material Type and voucher specimens were deposited in the collections of Western Ghat Field Research Centre of Zoological Survey of India, Kozhikode (ZSI/WGRC).

Authors’ contributions: PTA is the main worker on the topic, worked on illustrations and pictures and prepared the draft of the manuscript. PTA, KAH, NJS and AB conceived and designed research, critically reviewed for improving the quality of the manuscript, PTA and AB conducted the fieldwork. All authors read and approved the final manuscript.

Additional information

Funding

This study was funded by the University Grants Commission, New Delhi (No.F.4-2/2006 (BSR)/BL/16-17/0401; dated: 28; August 2017) through Post-Doctoral Fellowship to PTA and a National Research Foundation (NRF) of South Africa research grant to KAH Grant Nos 120240 and 120403.