Autumn populations of Branchinecta orientalis G. O. Sars, 1903 and Chirocephalus diaphanus Prévost, 1803 (Crustacea, Branchiopoda) in the Central European Lowlands (Pannonian Plain, Serbia)

Abstract

Autumn populations of two large branchiopod species, Branchinecta orientalis and Chirocephalus diaphanus in the area of southern part of Central European Lowlands (Pannonian Plain) are here reported for the first time. During surveys carried out in 2007–2013, autumn populations were observed in November 2009 (C. diaphanus) and in October 2012 (B. orientalis). Autumn specimens were smaller compared to those caught in spring. Although the two species were found in the same area, their habitats were spatially separated: B. orientalis was recorded only in the soda lake Rusanda, while C. diaphanus was found only in small ephemeral ponds placed over the surrounding meadows. Appearance of autumn populations point to the ecologically tolerant character of these species, and suggests they are able to tolerate lower temperatures during growth.