Integrative taxonomy: combining molecular and morphological characteristics to identify Lymnaea (Galba) cubensis, intermediate host of Fasciola hepatica

Abstract

Despite the epidemiological importance of the Lymnaeidae family regarding transmission of Fasciola hepatica, knowledge about the diversity and distribution of these molluscs and the role of each species in the expansion of fasciolosis remains sparse. Classical morphological (n=10) identification was performed in lymneids from Lagoa Santa, a municipality in the state of Minas Gerais, Brazil, along with molecular and phylogenetic analysis (n=05) based on the partial nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I gene (COI mtDNA) and ribosomal internal transcribed spacer II (ITS-2 rDNA). The shell morphology made it possible to distinguish the lymneids of Lagoa Santa from Pseudosuccinea columella. Differences found in the penile complex and prostate shape allowed this species to be distinguished from Galba truncatula. However, the homogeneity of reproductive tract characteristics among Lymnaea (Galba) cubensis, L. viator and L. neotropica confirmed that these characteristics show low taxonomic reliability for identifying cryptic species. Genetic divergence analysis for the COI mtDNA gene and ITS-2 region of rDNA revealed greater similarity to Lymnaea (Galba) cubensis. Thus, correct species differentiation is important for monitoring the epidemiological risk of fasciolosis in the state of Minas Gerais, where cases of the disease have increased over recent years.

Fasciolosis in ruminants in Brazil

“…However, reports of F. hepatica infection in other species of lymnaeid, such as L. rupestris , Galba viatrix , G. cubensis and G. truncatula , have been published ( Medeiros et al, 2014 ). In recent years, studies combining molecular and morphological techniques have made it possible to identify these intermediate hosts of F. hepatica ( Ferreira et al, 2021 ).…”

Survey on Limnic Gastropods: Relationships between Human Health and Conservation

“…Until recently, the occurrence of P. columella had been documented in 40 municipalities in Minas Gerais [35][36][37][38][39][40][41][42], but had not yet been recorded for Alvorada de Minas. Since fasciolosis is a zoonosis that can also affect humans and can cause serious clinical manifestations in chronically infected individuals [39], the present record might be also of interest in the view of a One Health perspective [35,43]. As such, cases of human fasciolosis have been reported in Brazil in studies from the states of Bahia, Minas Gerais, Mato Grosso do Sul, Paraná, Rio de Janeiro, Rio Grande do Sul, Santa Catarina, and from São Paulo [44].…”

Identification of freshwater snail species and survey of their trematode infections in Ordos, China

“…Correct identification of freshwater snails as well as trematode larvae in snails is essential to determine the epidemiological risk area of trematodes ( Ferreira et al, 2021 ). Currently, most of the freshwater snail species investigations are based on morphological identification.…”