DNA barcoding as a valuable tool for delimiting mollusk species of the genus Biomphalaria Preston, 1910 (Gastropoda: Planorbidae)

Abstract

IntroductionThe genus Biomphalaria in Brazil includes 11 species and one subspecies, three of which are intermediate hosts of Schistosoma mansoni. Due to the recent evolution of this group, some species are difficult to identify based on morphological characters, making the use of genetic markers necessary for species identification. This study aimed to evaluate the use of partial sequences of the cytochrome c oxidase I (coi) gene for the identification of Biomphalaria species using phylogenetic reconstruction and species delimitation algorithms. The study tested the use of DNA barcoding technique for species delimitation within the genus.MethodsDNA barcoding was performed by sequencing a partial region of the coi gene from specimens, and the sequences were analyzed using phylogenetic reconstruction and algorithms to delimit Operational Taxonomic Units (OTUs).ResultsThe study found that the use of the coi gene in the reconstruction of the phylogeny of the genus might be an alternative for understanding the evolution and dispersion of species. However, this marker alone is not enough to solve complex taxonomic problems within the genus. A total of 223 sequences were analyzed, 102 of which could be separated using the barcode gap, enabling the correct identification of seven taxa.DiscussionThe study demonstrated that accurate mollusk identification is necessary for effective schistosomiasis control. The DNA barcoding methodology was found to be promising for accurate mollusk identification, which is crucial for concentrating schistosomiasis control efforts in places where it is needed.

Update on the Geographic Distribution of the Intermediate Host Snails of Schistosoma mansoni on St. Lucia: A Step Toward Confirming the Interruption of Transmission of Human Schistosomiasis

“…The snail taxon we identified as B. kuhniana was relatively widely distributed on St. Lucia. It is appropriately cautious to consider our identification of the St. Lucian B. kuhniana specimens as provisional because it is clear from both the literature, 32 , 33 including a recent detailed study by de Araujo et al., 34 and from GenBank entries that B. kuhniana , B. straminea , and B. intermedia are closely related and may best be viewed as a complex of diverging species. Genetic distances between some isolates of provisional B. kuhniana and B. straminea fall in an ambiguous region of < 3% divergence.…”

Comparative Mitogenome Analyses of Fifteen Ramshorn Snails and Insights into the Phylogeny of Planorbidae (Gastropoda: Hygrophila)

“…Planorbinae was the most diverse subfamily, consisting of Camptoceratini, Coretini, Drepanotrematini, Helisomatini, Neoplanorbini, Planorbini, and Segmentinini. In recent years, a couple of molecular phylogenetic studies of Planorbidae have been reported, but mainly focused on two economically important genera, i.e., Biomphalaria and Bulinus, that infer the phylogeographic relationship using the mitochondrial gene of cox1 and rrnL, and nuclear gene 18S rDNA, 28 S rDNA and internal transcribed spacer (ITS) [21][22][23].…”