Cricotopus (Cricotopus) beckeri Hirvenoja 1973

Cricotopus (Cricotopus) beckeri Hirvenoja, 1973 Material examined. 1 pupal exuvium, Latoricja River (S 4), 5 May 2018; 1 pupal exuvium, Rika River (S 6); 2 pupal exuvia, Rika River (S 8) above Zaperedillia village, 7 May 2018. Distribution. Palaearctic. France, Spain, Greece, Madeira, Corsica, Turkey, Algeria, Morocco, Slovakia. Its questionable occurrence in Finland (Ashe and O’Connor 2012) was not accepted later Paasivirta (2014). Habitat. Principally inhabits the rhithral zone of streams at lower altitudes (Hirvenoja and Moubayed 1989; Kettani and Langton 2012; Moubayed-Breil and Ashe 2016). Remarks. Cricotopus beckeri has been considered an exclusively Mediterranean species (Laville and Reiss 1992). Our record is the second reliable finding in the Carpathians (Bitušík and Langton 1994) far from its continuous distribution. We assume that the isolated populations in the Carpathians could be remnants of once widespread populations, which currently survive in refugia due to adverse climatic conditions. Thus, they could be considered a climatic relict, as customary for some plant species (Molnár et al. 2017). Interestingly, Reiss (1986) already hypothesised that the extra-Mediterranean occurrence of another Mediterranean chironomid, Paratanytarsus mediterraneus Reiss, 1981, could have a relict character in the Middle Rhine.