A new genus of large hydrothermal vent‐endemic gastropod (Neomphalina: Peltospiridae). (October 2015)

• Record Type: Journal Article
• Authors: Chen, Chong; Linse, Katrin; Roterman, Christopher N.; Copley, Jonathan T.; Rogers, Alex D.
• Is Part Of: Zoological journal of the Linnean Society. Volume 175:Number 2(2015:Oct.)
• Page Start: 319
• Page End: 335
• Publication Date: 2015-10
• Subjects: Zoology -- Periodicals; 590
• DOI: 10.1111/zoj.12279
• Languages: English
• ISSNs: 0024-4082

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Recently discovered hydrothermal vent fields on the East Scotia Ridge (ESR, 56–60°S, 30°W), Southern Ocean, and the South West Indian Ridge (SWIR, 37°S 49°E), Indian Ocean, host two closely related new species of peltospirid gastropods. Morphological and molecular (mitochondrial cytochrome c oxidase subunit I, <italic>COI</italic>) characterization justify the erection of <italic><bold>G</bold></italic><bold><italic>igantopelta</italic> gen. nov.</bold> within the Peltospiroidae with two new species, <italic><bold>G</bold></italic><bold><italic>igantopelta chessoia</italic> sp. nov.</bold> from ESR and <italic><bold>G</bold></italic><bold><italic>igantopelta aegis</italic> sp. nov.</bold> from SWIR. They attain an extremely large size for the clade Neomphalina, reaching 45.7 mm in shell diameter. The oesophageal gland of both species is markedly enlarged. <italic>Gigantopelta aegis</italic> has a thick sulphide coating on both the shell and the operculum of unknown function. The analysis of a 579‐bp fragment of the <italic>COI</italic> gene resulted in 19–28% pairwise distance between <italic>Gigantopelta</italic> and six other genera in Peltospiridae, whereas the range amongst those six genera was 12–28%. The <italic>COI</italic> divergence between the two newly described species of <italic>Gigantopelta</italic> was 4.43%. Population genetics analyses using <italic>COI</italic> (370 bp) of 30 individuals of each species confirmed their genetic isolation and indicate recent rapid demographic expansion in both species. © 2015 The Linnean Society of London</p> </abstract>