Molecular phylogeny and trait evolution of Madeiran land snails: radiation of the Geomitrini (Stylommatophora: Helicoidea: Geomitridae)

Abstract

The Geomitrini is the most species-rich group of land snails in the Madeiran Archipelago. The phylogeny of the group is reconstructed based on mitochondrial and nuclear genetic markers. The timing of diversification, the colonisation history of the islands of the Madeiran Archipelago and the evolution of characters of the dart apparatus are studied. The results of the phylogenetic analyses confirm the sister group relationship of Geomitrini and Cochlicellini, but also show that several previously accepted genus-group taxa are not monophyletic. A new classification for the Geomitrini is proposed, including the description of two new genera, Domunculifex Brozzo, De Mattia, Harl & Neiber, n. gen. and Testudodiscula Brozzo, De Mattia, Harl & Neiber, n. gen. The onset of diversification of Geomitrini was dated in our analysis at 13 Ma, which largely coincides with the emergence of the present-day islands. The ancestral state estimation recovered the presence of two appendiculae in the reproductive system as the ancestral state in Geomitrini. One appendicula was lost three times independently within the tribe and is even missing completely in one group. The ancestral area estimation suggests recurrent colonisations of Madeira (and the Ilhas Desertas) from the older island Porto Santo.

De novogenome assembly of the land snailCandidula unifasciata(Mollusca: Gastropoda)

“…Previous work focused on the speciation ( Pfenninger and Magnin 2001 ; Pfenninger et al 2003 ) and climate-driven evolution ( Pfenninger and Posada 2002 ; Pfenninger et al 2007 ) of the genus, however, in depth analyses were hampered by the lack of genomic markers. Although, there are many taxonomical, phylogeographical, and evolutionary studies concerning Geomitridae species ( Pfenninger and Magnin 2001 ; Sauer and Hausdorf 2010 ; Brozzo et al 2020 ), the lack of reference genomes makes it difficult to investigate deeper biological and evolutionary questions about geomitrids and other land snails species. Here, we present the annotated draft genome of C. unifasciata that will be a valuable resource for future genomic research of this important taxonomic group ( Chueca et al 2021 ).…”

Intercontinental dispersal and niche fidelity drive 50 million years of global diversification in Vertigo land snails

“…Previous phylogenetic work on terrestrial gastropods has either been limited to smaller spatial scales (e.g. Brozzo et al., 2020; Neiber et al., 2022; Razkin et al., 2015) or featured less comprehensive sampling of included clades (e.g. de Weerd & Gittenberger, 2013; Saadi et al., 2021; Teasdale, 2017; Wade et al., 2006).…”

One-health approach on the future application of snails: a focus on snail-transmitted parasitic diseases

“…Angiostrongylus cantonensis (rat lungworm), the causative agent for angiostrongyliasis, is a nematode parasite having a complex life cycle where rats are the final hosts, gastropods (snails) act as intermediate hosts, and with several paratenic hosts (freshwater prawns/shrimp, crabs, flatworms, fish, frogs, toads, lizards, and centipedes) (Turck et al 2022 ). The wide range of snail species (more than 60) belonging to gastropods is responsible for harboring the intermediate larval stage of this nematode (Brozzo et al 2020 ; Segeritz et al 2021 ; Turck et al 2022 ). Since the wide range of infections occurs in different snail species and humans and other animals, it is crucial to raise awareness of the associated dangers of consuming snails as food and feeding materials.…”