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Issue: Vol. 5839 No. 3: 30 Jun. 2026
Type: Article
Published: 2026-06-30
DOI: 10.11646/zootaxa.5839.3.2
Page range: 439-469
Abstract views: 327
PDF downloaded: 23

Integrative Species Delimitation of Carrier Snails (Caenogastropoda: Stromboidea: Xenophoridae) with a New Genus and Five New Species

Department of Ecology and Evolutionary Biology; University of Michigan; Ann Arbor; MI; USA; Division of Mollusks; University of Michigan Museum of Zoology; University of Michigan; Ann Arbor; MI; USA
Malakos Malacological Museum; Loc. Garavelle; Città di Castello (PG); 06012 Italy; Via Torino 30; Decimomannu (CA); 90933 Italy
Institut Systématique Evolution Biodiversité (ISYEB); Muséum National d’Histoire Naturelle; CNRS; Sorbonne Université; EPHE; Université des Antilles; 43 rue Cuvier; CP 51; F-75005 Paris; France
Mollusca Mollusc new species morphology cox1 Xenophoridae

Abstract

Cryptic speciation is widely documented in marine gastropods, particularly in groups lacking distinct morphological characters. Carrier snails of the family Xenophoridae have long been celebrated by naturalists for their behavior of collecting and affixing foreign objects to their shells. We present the first molecular species delimitation of carrier snails (family: Xenophoridae), using cox1 sequences from 562 specimens encompassing 81% of valid species and all genera in this family. Integrating alpha-taxonomic data, we formalize five new species in descriptions—Xenophora simulans sp. nov., Xenophora brevis sp. nov., Onustus procellosus sp. nov., Collector altissimus gen. nov. et sp. nov., Collector alienus gen. nov. et sp. nov.—and recommend further investigations into other promising clades with potentially undiscovered species, pending corroboration from nuclear loci. This case study highlights the potential of species discovery using single-locus delimitation methods. We established a baseline framework for morphological species delimitation in Xenophoridae, showing that specimens distinguished only by subtle morphological characters often interpreted as intraspecific variation can exhibit species-level genetic divergence.

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How to Cite

Tan, Y.K., Nappo, A. & Bouchet, P. (2026) Integrative Species Delimitation of Carrier Snails (Caenogastropoda: Stromboidea: Xenophoridae) with a New Genus and Five New Species. Zootaxa, 5839 (3), 439–469. https://doi.org/10.11646/zootaxa.5839.3.2