This study presents basic information on Plecoptera taxocenoses inhabi
ting the Vtacnik mountain range. The nymph morphology and ecology of t
wo Carpathian endemics, Nemoura carpathica and Leuctra pusilla, is dis
cussed. The predominant stoneflies species have central European and m
ore particularly south-central European distribution. The river basin
draining the Vtacnik massif represents the south-west border of the mo
untain and submountain stoneflies distribution. In the Vtacnik mountai
ns the following communities have been distinguished: the crenal mount
ain community, the spring-brooklets and mountain brook community, the
mountain torrents community (all inhabited by cold stenothermal specie
s), the eurythermal community (rheophilous and nonrheophilous species
occurring in different types of lotic biotopes), and the mesothermal c
ommunity, restricted to warmer submountainous streams.