Contribution to the macroinvertebrate fauna of the Hungarian Danube. V. Amphipods (Crustacea: Malacostraca: Amphipoda)

This paper provides occurrence data of amphipod species collected by the staff of the Hungarian Danube Research Station from 1994 to 2009. Altogether 751 samples from 209 sampling locations of the Hungarian Danube section (main channel, side branches, and adjacent wetlands) were processed, and 12 species were identified. Introduction, materials and methods The main objective of this paper is summarising the faunistic results concerning amphipod crus- taceans collected in different macroinvertebrate investigations carried out by the Hungarian Danube Research Station of the Hungarian Academy of Sciences in the water system of the Danube River (main channel, side branches, and adjacent wetlands) between 1994 and 2009. Detailed descriptions of sampling sites and methods, and the explanations of the abbreviations can be found in NOSEK (2007). During the different investigations - according to the purpose of the given survey - several qualitative, semi-quantitative, and quantitative sampling techniques and devices were used such as: sampling by hand and forceps (C), hand net with "kicking & sweeping" technique by ISO 7828 type net (H), triangular dredge (D), their combinations (CD, CK, DC, HC, HD, HDC), Ekman-Birge grab (G), Surber sampler (S), hand net among aquat- ic macrovegetation (K), hand net without "kicking & sweeping" technique (V), and artificial (M) clay (A) and gravel (K) substrates used in long (h) and short (r) period colonization exper- iments on the surface (F) and at the bottom (L) of the river (Mh-AF, Mh-AL, Mh-KL, Mr-AF, Mr-AL, Mr-KL, respectively) (OERTEL 2000, 2002, OERTEL & NOSEK 2004, 2006). Samples were fixed in-situ in 4% formaldehyde solution. After separation crustaceans were preserved in 70% ethanol. The animals were identified based on the works of CARAUSU et al. 1955, DUDICH 1955, EGGERS & MARTENS 2001, 2004, JAZDZEWSKI & KONOPACKA 1996, KONTSCHAN et al. 2002. Nomenclature of amphipods was used after EGGERS & MARTENS (2004) and MUSKO (2007). Samples were taken along the whole 417 km long Hungarian Danube reach, from its side branches (Szentendrei Danube, Rackevei (Soroksari) Danube, Neszmely-Mocsi, Tati, Godi side- branches), from the water bodies of adjacent wetlands (Szigetkoz area: abandoned main channel - the "Old Danube", active alluvial flood plain, the flood-protected area, Mosoni Danube; Ge- menc Landscape Protection Area, - "Gemenc"; Beda-Karapancsa Landscape Protection Area). The results section of the article contains the code of the sampling locality, code of the method, date of collection and monogram of collectors (in parentheses), respectively. The data are arranged in alphabetical order of the code of the sampling sites. Different collecting dates belonging the same sampling locality and method are listed in chronological order. In this paper