Taxonomia integrativa dos gêneros synapterpes e lopesianus (gastropoda, stylommatophora) no Brasil, com proposta de uma nova família

Abstract

Species of the terrestrial gastropod genera Synapterpes, which previously had two species recognized for Brazil, and Lopesianus, considered monotypic, are endemic to the Atlantic Forest of Rio de Janeiro State. Until now, there were no phylogenetic studies for these taxa, nor descriptions of the morphology of L. crenulatus. The classification of both has also been controversial. This work reviewed the taxonomy of these genera, describing the Brazilian species, and assessed their monophyly and phylogenetic proximity to each other and to other families of Stylommatophora. To this end, the specimens were analyzed morphologically and, whenever possible, molecularly. Morphological analyses were performed of the shell, cephalopod mass, mantle, pallial cavity, radula, and mandible (SEM), as well as the reproductive system, including histological analyses of accessory structures. Phylogenetic analyses were conducted using the COI, 28S, and H3 markers, individually and concatenated. The results revealed three new species for Synapterpes and the redescription of S. hanleyi. Lopesianus was maintained as monotypic, including the species L. crenulatus, described morphologically for the first time. Synapterpes' geographic distribution was restricted to preserved fragments of the Atlantic Forest, where it was rarely found. Lopesianus crenulatus, on the other hand, was restricted to Atlantic Forest restinga environments in Arraial do Cabo, RJ, and was more commonly found than Synapterpes species. It was found that Synapterpes and Lopesianus, previously classified in distinct superfamilies, share several conchological and morphological similarities, such as the presence of unique accessory reproductive structures: an atrial gland, a vaginal gland, and a pre-spermathecal sac. Similar behaviors were recorded, and the parasite Cruzia tentacula was, for the first time, associated with species of both genera. Molecular phylogenetic analyses confirmed the morphological results, demonstrating the monophyly of the two genera and their status as sister taxa. They also revealed that they form an independent and well-supported clade within the superfamily Orthalicoidea, necessitating the creation of a new family for proper classification.