Hidden diversity in a hyperdiverse gastropod genus: discovery of previously unidentified members of a Conus species complex.
Molecular sequence data are a powerful tool for delimiting species, particularly in cases where morphological differences are obscure. Distinguishing species in the Conus sponsalis complex of tropical marine gastropods has long been difficult, because descriptions and identification has relied exclusively on shell characters, primarily color patterns, and these often appear to intergrade among putative species. Here we use molecular sequence data from two mitochondrial gene regions (16S rRNA and cytochrome oxidase subunit I) and one nuclear locus (a four-loop conotoxin gene) to characterize the genetic discontinuity of the nominal species of this group currently accepted as valid: the Indo-West Pacific C. sponsalis, C. nanus, C. ceylanensis, C. musicus and C. parvatus, and the eastern Pacific C. nux. In these analyses C. nanus and C. sponsalis resolve quite well and appear to represent distinct evolutionary units that are mostly congruent with morphology-based distinctions. We also identified several cryptic entities whose genetic uniqueness suggests species-level distinctions. Two of these fit the original description of C. sponsalis; three forms appear to represent C. nanus but differ in adult shell size or possess a unique shell color pattern.
Duda
Thomas F
TF
Department of Ecology and Evolutionary Biology, Museum of Zoology, University of Michigan, 1109 Geddes Avenue, Ann Arbor, MI 48109, USA. tfduda@umich.edu
Bolin
Matthew B
MB
Meyer
Christopher P
CP
Kohn
Alan J
AJ
D000818:Animals; D001499:Bayes Theorem; D020916:Conotoxins / Q000235:genetics; D052078:Conus Snail / Q000033:anatomy & histology / Q000145:classification / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics; D019143:Evolution, Molecular; D050259:Genes, Mitochondrial; D020459:Genes, rRNA; D016013:Likelihood Functions; D008928:Mitochondria / Q000235:genetics; D008957:Models, Genetic; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013045:Species Specificity
D020916:Conotoxins; D004272:DNA, Mitochondrial; D012336:RNA, Ribosomal, 16S; D003576:Electron Transport Complex IV