New record for Galba neotropica (d'Orbigny, 1835) in Argentina, with a detailed analysis of its morphology and molecular characteristics

Abstract

We report for the first time the presence of Galba neotropica in Santa Fe province, Pampean Argentina. Until the present work, the identity of the intermediate host of Fasciola hepatica in this region, the most important livestock production area of Argentina, was unknown. This report extends the geographic distribution of G. neotropica and is the first to provide molecular and morphological information on this species in Argentina. During summer 2013, snails were collected on private livestock farms with high prevalence of fasciolosis in cattle. Specimens were identified by using the nuclear sequences of the internal transcribed spacers ITS-1 and ITS-2, the shell and the shape and size of the male reproductive organs. Molecularly, ITS-1 and ITS-2 nuclear sequences exhibit 100% nucleotide identity with G. neotropica from Lima, Peru. Morphologically, G. neotropica from Santa Fe province was indistinguishable from Galba viatrix and Galba cubensis, the other two cryptic species within this South American group of lymnaeids. The combination of molecular and morphological analyses is strongly recommended to identify lymnaeids at species level. The identity of the intermediate host and the subsequent knowledge of its susceptibility, behaviour, distribution, ecology and biology are important components in developing effective measures to control fasciolosis.

Keywords:

• cryptic species
• fasciolosis
• intermediate host
• distribution
• identity

Acknowledgements

We thank the Secretaría de Medio Ambiente of Santa Fe province for permission to collect snails. We are deeply indebted to the owners of the private livestock farms that were visited. The help by M.V. Juan Ventura is acknowledged. We also thank Verónica Ivanov for her collaboration in drawing figures and Marcela Rodriguero for her valuable help.

We thank the referees for their critical comments on an earlier version of this article that have helped to improve our manuscript. This work received financial support from Agencia Nacional de Promoción Científica y Tecnológica of Argentina through grant PICT 2011–00031 and from Consejo Nacional de Investigaciones Científicas y Técnicas of Argentina through grants PIP 112–200801–00821 and CONIET-Ibol 2011.

Disclosure statement

No potential conflict of interest was reported by the authors.