Abstract
A new species of vermetid gastropod belonging to the genus Novastoa Finlay, 1926, N. rapaitiensis sp. nov., is described from French Polynesia and the Great Barrier Reef, based on morpho-anatomical and molecular data, increasing the recognized extant diversity of this genus from five to six species. The new species is characterized by the largest operculum in the genus to date, with a conspicuous spindle-shaped mammilla that readily distinguishes this species from its congeners. Based on available data, members of the studied populations of N. rapaitiensis sp. nov. are interpreted as a single species, although slight morphological and color differences exist between localities separated by up to 7000 km. The larval development of N. rapaitiensis sp. nov. is inferred to be direct, raising new questions about genetic connectivity and dispersal trajectories across a vast geographic range. Additional molecular data may prove helpful in refining our current knowledge on the morphological variability within this species and verifying the degree of cryptic diversity in this genus.
Highlights
Vermetidae is a family of caenogastropods characterized by a sessile habit and uncoiled shells whose taxonomy has remained in a state of flux for decades due to their highly variable shell features.There are close to 300 existing names available for extant vermetid species (Bieler & Petit 2011)
A new species of vermetid gastropod belonging to the genus Novastoa Finlay, 1926, N. rapaitiensis sp. nov., is described from French Polynesia and the Great Barrier Reef, based on morpho-anatomical and molecular data, increasing the recognized extant diversity of this genus from five to six species
All these genera are characterized by markedly different and elaborated opercula, with Novastoa standing as an extreme case, with the conical, concave, and thick opercula bearing a conspicuous nipple- or spindle-shaped mammilla on the body side. The function of this ‘oversized’ mammilla is unknown, but could reasonably represent an aid in preventing operculum removal by predators (Golding et al 2014). In this contribution we describe a new species of Novastoa, N. rapaitiensis sp. nov., from French Polynesia and the Great Barrier Reef, with the largest known, spindle-shaped development of the mammilla on the operculum
Summary
Vermetidae is a family of caenogastropods characterized by a sessile habit and uncoiled shells whose taxonomy has remained in a state of flux for decades due to their highly variable shell features.There are close to 300 existing names available for extant vermetid species (Bieler & Petit 2011). All four genera were strongly supported in a molecular phylogenetic analysis of select vermetid taxa in Golding et al (2014), with Dendropoma and Ceraesignum forming a robust monophyletic grouping, and with Novastoa and Cupolaconcha more closely related to other vermetid groups. All these genera are characterized by markedly different and elaborated opercula, with Novastoa standing as an extreme case, with the conical, concave, and thick opercula bearing a conspicuous nipple- or spindle-shaped mammilla on the body side. The function of this ‘oversized’ mammilla is unknown, but could reasonably represent an aid in preventing operculum removal by predators (Golding et al 2014)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
