Revisão do gênero Neotropical Gundlachia Pfeiffer, 1849 (Mollusca, Pulmonata, Basommatophora, Planorboidea, Ancylidae): morfologia, distribuição geográfica, sistemática e filogenia

Abstract

Gundlachia Pfeiffer 1849 is the freshwater pateliform snail genus with the widest geographical distribution among the eight genera of "Ancylidae" marked for the Neotropical region. The pateliforme shell, considered as one homoplasy by several authors in various basommatophorans, has historically been used to define the family unit Ancylidae despite questions against the monophyly of the group. Molecular data confirmed that Ancylidae is a paraphyletic group, mainly because of Burnupia genus. The other genera were included in Ancylinae within Planorbidae. However, the absence of phylogenies with molecular basis including all Neotropical genera is still an issue that needs to be investigated. The main objectives of this study was: (a) review the species of Gundlachia through morphological studies of their shells and soft tissues; (b) standardize the descriptions of the species providing a basis to begin a cladistic analysis of the genus; (c) begin a molecular biology study using different species of representatives of Ancylinae to check their interrelationship and the likely sister group of Gundlachia; (d) and finally, build a geographic distribution map. For that, we examined several scientific collections and collections were conducted in the type localities. The morphology of the shells was compared by morphometric analysis under light and scanning microscopes. The soft tissues of the specimens were dissected and studied under a stereoscopic microscope. Molecular analysis was performed on three specimens of each sample using the genes of cytochrome c oxidase I and 16S mtDNA. Sequences were used to verify genetic distances between Gundlachia species and their relation with other genera through Neighbor-joining and Maximum likelihood test. With this study we present the new description of some species of Gundlachia, discuss the validity of new taxa discovered and sequenced and analyzed species of seven genera of Ancylinae that occur in the Neotropical region. Based on these data we discussed the monophyly of Gundlachia and their likely sister group. And we address the validity of the other Neotropical genera