Uncovering the shell game with barcodes: diversity of meiofaunal Caecidae snails (Truncatelloidea, Caenogastropoda) from Central America

By

Egger, Christina
Neusser, Timea P.
Norenburg, Jon
Leasi, Francesca
Buge, Barbara
Vannozzi, Angelo
Cunha, Regina L.
Cox, Cymon
Jörger, Katharina M.

Type

Article

Date of Publication

2020

Original Publication

ZooKeys

Volume

968

Pages

1--42

Subjects

DNA taxonomy , marine biodiversity , meiofauna , molecular species delineation , Mollusca

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.968.52986

 

Abstract

Caecidae is a species-rich family of microsnails with a worldwide distribution. Typical for many groups of gastropods, caecid taxonomy is largely based on overt shell characters. However, identification of species using shell characteristics is problematic due to their rather uniform, tubular shells, the presence of different growth stages, and a high degree of intraspecific variability. In the present study, a first integrative approach to caecid taxonomy is provided using light-microscopic investigation with microsculptural analyses and multi-marker barcoding, in conjunction with molecular species delineation analyses (ABGD, haplotype networks, GMYC, and bPTP). In total 132 specimens ofCaecumandMeiocerascollected during several sampling trips to Central America were analyzed and delineated into a minimum of 19 species to discuss putative synonyms, and supplement the original descriptions. Molecular phylogenetic analyses suggestMeioceras nitidumandM. cubitatumshould be reclassified asCaecum, and the genusMeiocerasmight present a junior synonym ofCaecum. Meiofaunal caecids morphologically resemblingC. glabrumfrom the Northeast Atlantic are a complex of cryptic species with independent evolutionary origins, likely associated with multiple habitat shifts to the mesopsammic environment.Caecum invisibileEgger & Jörger,sp. nov.is formally described based on molecular diagnostic characters. This first integrative approach towards the taxonomy of Caecidae increases the known diversity, reveals the need for a reclassification of the genusCaecumand serves as a starting point for a barcoding library of the family, thereby enabling further reliable identifications of these taxonomically challenging microsnails in future studies.