Non-indigenous invasive freshwater crustaceans (Crustacea: Malacostraca) in Slovakia - page 2

Results and Discussion

In total, 38 species belonging to four orders (Decapoda, Amphipoda, Isopoda and Mysida) of the class Malacostraca are detected in Slovak surface waters (Šporka, 2003). Among them, 23 species belong to the order Amphipoda, 3 species to Mysida, 7 species to Decapoda and 5 species to Isopoda. Based on original work and former data, 17 non-indigenous species of higher crustaceans (Malacostreaca) inhabit the aquatic ecosystems in Slovakia (Table 2). Nine species belong to the order Amphipoda, 4 to the order Decapoda, 3 to the order Mysida and 1 to the order Isopoda (Brtek and Rothschein, 1964; Nesemann et al., 1995; Šporka, 1999; Brtek, 2001; Souty-Grosset et al., 2006; Petrusek and Petrusková 2007; Borza, 2007; Borza, 2009; Puky, 2009; Janský and Mutkovič, 2010; Lipták et al., 2012).

Comparing the list of native and non-indigenous species, 44.7% of the studied malacostracan species known from Slovakia are of non-indigenous origin. These species originate mainly from the Ponto-Caspian region, from which some are actively spreading upstream the Danube River (e.g. Obesogammarus obesus) or as a result of human-mediated transport (e.g. to the Upper Danube), consequently spreading downstream the river from the introduced site (e.g. Echinogammarus trichiatus) (Bij de Vaate et al., 2002; Borza, 2009).

During the original research conducted in 2011, 8 species of exotic amphipods and one isopod were recorded (Table 2). Indigenous amphipods were absent in the main course of the Danube River and its tributaries (the Lower Morava and Váh River). Species richness and abundance per sampling site is presented in Table 3. Distribution of the species is evaluated synthesizing the original research results with the former studies (Figures 1-12).

 

Table 2: List of the non-indigenous species and their distribution in Slovakia
Tab02

 

Table 3: Species recorded during the study conducted in 2011.
Tab03