Composição da malacofauna límnica da microrregião de Juiz de Fora, Zona da Mata, MG

Abstract

The aim of this study was to realize a malacological survey and to investigate the presence, distribution of Fasciola hepatica so as to evaluate the presence of infected individuals of Pseudosuccinea columella in water collections at the micro region of Juiz de Fora, Minas Gerais, Brazil, in the years 2009, 2011 and 2012. In the first chapter, results of species composition are presented, with a list of these species and information about its distribution. The collections were made in 22 localities, being the snails collected by direct collections. It were found 9 gastropod species in Juiz de Fora microregion: Melanoides tuberculatus (Müller, 1774) (Thiaridae); Biomphalaria tenagophila (d´Orbigny, 1835); (Planorbidae), Pseudosuccinea columella (Say, 1817) (Lymnaeidae); Stenophysa marmorata (Guilding, 1828), Haitia acuta (Draparnaud, 1805) e Afrophysa brasiliensis (Küster, 1844) (Physiidae); Pomacea sp. (Perry, 1810) (Ampullariidea), Gundlachia sp. (Pfeiffer, 1849) Ancylidae and the pulmonate stylommatophora Omalonyx sp. (d´Orbigny, 1937) (Succineidae). It were collected 719 snails, being 29,6% H. acuta, 0,97% S. marmorata, 0,83% A. brasiliensis, 56,8% P. columella, 5,14% B. tenagophila, 5% Gundlachia sp., 0,13% Melanoides tuberculatus and 1,39% Pomacea sp. Among these, four are alien species: M. tuberculatus, P. columella, S. marmorata and H. acuta. In the second chapter it was registered the occurrence of S. marmorata and A. brasiliensis in Juiz de Fora, with information on distribution and a detailed morphological study of the species. The third chapter presents a study that aimed to investigate the presence, distribution and to evaluate the possibility of infection by F. hepatica in the freshwater snail P. columella. The collections were realized in 22 in lotic and lentic aquatic ecossystems. It were collected 409 specimens in 04 of 22 collections points that comprised streams, dams, lakes, lagoons and irrigation ditches. The morphological studies of specimens allowed the identification of P. columella. The research of larval forms of trematodes was realized by exposure to artificial light. No infected snails were found. The occurrence of fasciolosis is related to the presence of snails of the genus Lymnaea, in this way, it is important to realize studies in order to monitoring different regions of Brazil were intermediate hosts are found, that are potential areas to the establishment of the disease. The present study is the first study of freshwater malacological composition in the microregion of Juiz de Fora, Minas Gerais. The survey of this fauna in this region is of fundamental importance to the knowledge of occurrence and distribution of native species, besides the recognition of the presence and distribution of native and alien species and helminth hosts, serving as threshold for the development of control strategies.