Larval trematodes (Digenea) of the great pond snail,Lymnaea stagnalis(L.), (Gastropoda, Pulmonata) in Central Europe: a survey of species and key to their identification

Abstract

Summary :A survey of cercariae and metacercariae (Trematoda, Digenea) from the great pond snail (Lymnaea stagnalis) in Central Europe (Austria, Czech Republic, South-East Germany, Poland and Slovak Republic) is presented, based on a study of 3,628 snails examined from 1998 to 2005. A total of 953 (26.3 %) L. stagnalis were infected with 24 trematode species comprising 19 species of cercariae and 11 species of metacercariae (six species occurred both as cercarie and metacercarie) of eight families. The dominant cercariae were those of Opisthioglyphe ranae (159 hosts infected), Plagiorchis elegans (141) (both family Plagiorchiidae) and Echinoparyphium aconiatum (153) (Echinostomatidae); 14 double infections were found. The most frequent metacercariae were those of Neoglyphe locellus (71) (Omphalometridae), E. aconiatum (66), Echinostoma sp. (59) and Moliniella anceps (48) (Echinostomatidae). In the previous studies carried out in Central Europe, a very similar spectrum of nine trematode families of 22 cercariae determined to species level and 43 types of cercariae reported under generic or provisional names, which can be in many cases conspecific with the previous taxa, were found. A simple key to identification of cercariae and metacercariae, together with their illustrations, is provided. Résumé

Cercariae (Trematoda, Digenea) in European freshwater snails - a checklist of records from over one hundred years

“…Mainly the families Lymnaeidae and Planorbidae have been investigated which results from the easier availability and high frequency of occurrence of these snails, especially the big-sized species: Lymnaea stagnalis and Planorbarius corneus (PIECHOCKI 1979, JACKIEWICZ 2000, LOY & HAAS 2001, FALTÝNKOVÁ et al 2007, 2008. Moreover, these two snail families are mostly responsible for spreading of parasites which are important from the medical and veterinary point of view.…”

Microhabitat differences surrounding a pond affects the distribution of trematode parasites among a pulmonate snail community

“…A subset of 150 snails, 50 from each habitat classification that were randomly selected from multiple transects within each category, was necropsied each month for an estimation of how many snails harbored pre-patent infections (i.e., possessing asexually reproducing sporocysts or rediae, but not yet shedding cercariae) and to provide a better estimation of the infection dynamics of the trematode parasites. All shed cercariae were isolated, identified, and then sub-categorized into autogenic and allogenic species Schell, 1985;Faltynkova et al, 2007, Faltynkova et al, 2008). The population was described in terms of prevalence (i.e., a binary measurement referring to the presence or absence of a trematode infection) according to the terminology of Bush et al (1997) and is expressed as a percentage by dividing the number of infected snails by the total number of snails sampled.…”

Community structure and systematic study of Helminth parasites of freshwater snails of the Chittagong University Campus

“…In many works (Ismail et al 1988, Krailas et al 2003, Rahman and Jahan 2006, Moema et al 2008, Martorelli et al 2013, cercaria-identification was not more definite than that of the level in which the present work has been done. However, binomial nomenclature of cercariae has been given by a number of workers (Ditrich et al 1997, Jezewaski 2004, Faltynkova et al 2007b, Choubisa 2008, Gautam and Kakulte 2014 Xiphidiocercous cercariae: Five morphotypes, designated here as XA 1 , XA 2 , XB 1 , XB 2 and XC, were collected. In none of them, structures like the pharyngeal bulb, intestinal caeca, cystogenous glands and the excretory vesicle were at all developed.…”

“…Many workers (Ghobadi and Farahnak 2004, Faltynkova et al 2007b, Dechruksa et al 2007, Sharif et al 2010, Jayawardena et al 2010, Bdir and Adwan 2012 also reported vast dominance of single infection by DST in various snail species including B. bengalensis. Presently, only six snails had double infection by DST types -four by X + E and two by X + F. No two morphotypes of any of the cercarial groups (e.g., like XA 1 + XC, or E 1 + E 2 ) were present in multiple infection, indicating the avoidance of interspecific competition among the closely related members.…”