Checklist of the fresh and brackish water snails (Mollusca, Gastropoda) of Bénin and adjacent West African ecoregions

Zinsou Cosme Koudenoukpo,Rose Sablon,Olaniran Hamed Odountan,Bert Van Bocxlaer,Thierry Backeljau,Antoine Chikou

doi:10.3897/zookeys.942.52722

Abstract

Currently no comprehensive checklist of fresh and brackish water gastropods from Bénin exists, and those for adjacent West African areas are outdated. Yet, such checklists provide essential biodiversity information and a consistent taxonomic and nomenclatural framework for that biodiversity. Here a first checklist of the fresh and brackish water gastropods from Bénin and adjacent West African ecoregions is presented, based on an extensive literature review and field surveys between September 2014 and June 2019 in six major fresh and brackish water ecosystems in Bénin. This inventory includes information on synonymy, species distribution in West Africa, habitats, and conservation status. The fresh and brackish water gastropod fauna includes 60 species, belonging to 28 genera and 16 families. Pachychilidae, Ampullariidae, Neritidae, and Bulinidae were the most diverse families with 9, 8, 7, and 7 species, respectively. However, literature and field data indicated that 23 species observed in West African basins that extend to Bénin do not occur in the territory of Bénin. These species were not detected in our field surveys, most likely because they are rare at collecting sites. Of the 60 species included, five are classified as “Data Deficient”, 43 as “Least Concern”, two as “Nearly Threatened”, one as “Vulnerable”, and six as “Endangered” by the IUCN, whereas the remaining three species were not evaluated. Because the taxonomy of fresh and brackish water gastropods in West Africa is still largely based on morphology, comparative molecular and taxonomic studies may result in substantial revisions of this checklist over the coming years.

Highlights

Mollusca are the second largest animal phylum on Earth, after Arthropoda, and comprise estimated numbers of 50,000–55,000, 25,000–30,000 and 6,000–7,000 of described and valid marine, terrestrial and freshwater species, respectively (Strong et al 2008; MolluscaBase 2019b)
As much legislative work depends on a validated overview of taxonomic biodiversity (Araujo and Jong 2015), biodiversity inventories are essential for the development of monitoring strategies and conservation policies
Bénin is located in West Africa between 6°15' and 12°25'N latitude and between 0°45' and 4°00'E longitude

Summary

Introduction

Mollusca are the second largest animal phylum on Earth, after Arthropoda, and comprise estimated numbers of 50,000–55,000, 25,000–30,000 and 6,000–7,000 of described and valid marine, terrestrial and freshwater species, respectively (Strong et al 2008; MolluscaBase 2019b). The largest molluscan class, Gastropoda (83% of accepted mollusc species), has repeatedly and successfully colonized continental waters on all continents, except Antarctica (Strong et al 2008; MolluscaBase 2019b). Despite their economic interest and ecological importance in many aquatic ecosystems (Wanninger and Wollesen 2019), our understanding of their biodiversity is far from complete, especially in developing countries, where expertise, resources and facilities for biodiversity studies are limited (Odountan et al 2019a). There is an increasing demand from policy makers and managers to readily have access to datasets regarding biodiversity (Gofas et al 2017)

Methods

Results

Conclusion