Range expansion of Ponto-Caspian mysids (Mysida, Mysidae) in the River Tisza: first record of Paramysis lacustris (Czerniavsky, 1882) for Hungary

Abstract

In the River Tisza, the longest tributary of the Danube,Limnomysis benedeniCzerniavsky, 1882 had been the only mysid recorded until recently. In 2011, we found a few juvenile specimens ofHemimysis anomalaG. O. Sars, 1907 in two daytime samples taken from the Hungarian river section. During the overnight survey in 2012 aimed at revealing the actual distribution of this nocturnally active species, its most upstream occurrence was detected at Szolnok (river km 334).Paramysis lacustris(Czerniavsky, 1882) was also found at every sampling site of the river downstream of Tiszabercel (rkm 568), representing the first record of the species for the fauna of Hungary, and its most upstream self-sustaining population in the basin of the River Danube (1759 rkm from the Danube mouth).P. lacustrisis the fourth Ponto-Caspian mysid that has begun to expand its range spontaneously in the Danube catchment afterL. benedeni,H. anomala, andKatamysis warpachowskyiG. O. Sars, 1893. Due to its zooplanktivory it can be anticipated to have a considerable effect on the composition and abundance of the zooplankton assemblages and it may also become an important food source for certain fish species, especially in the impounded reaches and in stagnant or slow-flowing backwaters.P. lacustris — similarly toH. anomala — shows a diel vertical migration, moving to shallow waters only by night, which calls for increased attention in order to reveal its possible future range expansions. Although the River Tisza itself is not connected directly to other river basins via canals, it may potentially contribute to the further spread of the species (e.g., via fish stocking).

The Ponto-Caspian mysid Paramysis lacustris (Czerniavsky, 1882) has colonized the Middle Danube

“…In the River Danube, the native range of the species was restricted to the lower ∼ 600 river km (Wittmann, 2007); however, during the latest international survey on the river ("Joint Danube Survey 3," 2013), its upstream distributional limit corresponded approximately to the confluence with the River Tisza (river km ∼1200, Fig. 2; Borza et al, 2015) in accordance with its previous range expansion in this tributary (Borza and Boda, 2013). P. lacustris was first detected in the Hungarian Danube section in the summer of 2017.…”

Migration and isolation during the turbulent Ponto‐Caspian Pleistocene create high diversity in the crustacean Paramysis lacustris

“…). Recently, it has expanded its distribution along the Danube River (Borza & Boda ) and it is only a matter of time until it spreads further. Attempts to identify invasion sources should be cautious about drawing conclusions if only limited samples are available.…”

“…P. lacustris is one of the most common crustacean species in Ponto-Caspian estuaries and also one of the most popular species used for intentional translocations in the former Soviet Union (Arba ciauskas et al 2010). Recently, it has expanded its distribution along the Danube River (Borza & Boda 2013) and it is only a matter of time until it spreads further. Attempts to identify invasion sources should be cautious about drawing conclusions if only limited samples are available.…”

Use of self-organizing maps in modelling the distribution patterns of gammarids (Crustacea: Amphipoda)

“…Climatic changes, human induced stress or disturbance events do also often coincide with invading native species which results in altering the previous community pattern (Borics et al 2013). The above is also true for the gammarid communities of European and Hungarian rivers, as two non-native Mysids appeared or extended their range of distribution at the last five years in Hungarian waters (Borza et al 2011, Borza andBoda 2013).…”