Open AccessA new genus of large hydrothermal vent‐endemic gastropod ( N eomphalina: P eltospiridae)
Author(s) -
Chen Chong,
Linse Katrin,
Roterman Christopher N.,
Copley Jonathan T.,
Rogers Alex D.
Publication year - 2015
Publication title -
zoological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.148
H-Index - 83
eISSN - 1096-3642
pISSN - 0024-4082
DOI - 10.1111/zoj.12279
Subject(s) - biology , genus , genetic divergence , ridge , operculum (bryozoa) , zoology , range (aeronautics) , cytochrome c oxidase subunit i , clade , population , hydrothermal vent , subgenus , mitochondrial dna , phylogenetics , paleontology , gene , hydrothermal circulation , genetic diversity , genetics , materials science , demography , sociology , composite material
Recently discovered hydrothermal vent fields on the E ast S cotia R idge ( ESR , 56–60° S, 30° W ), S outhern O cean, and the S outh W est I ndian R idge ( 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 , COI ) characterization justify the erection of Gigantopelta gen. nov. within the Peltospiroidae with two new species, Gigantopelta chessoia sp. nov. from ESR and Gigantopelta aegis sp. nov. from SWIR . They attain an extremely large size for the clade N eomphalina, reaching 45.7 mm in shell diameter. The oesophageal gland of both species is markedly enlarged. G igantopelta aegis has a thick sulphide coating on both the shell and the operculum of unknown function. The analysis of a 579‐bp fragment of the COI gene resulted in 19–28% pairwise distance between G igantopelta and six other genera in P eltospiridae, whereas the range amongst those six genera was 12–28%. The COI divergence between the two newly described species of G igantopelta was 4.43%. Population genetics analyses using COI (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