Checklist of free-living nematode species in the transitional environment of Lake Varano (southern Italy)

Abstract

This study documents for the first time the taxonomic composition of the nematode community and the number of free-living nematode species in Lake Varano, Southern Adriatic Sea, Italy. The nematode community was mainly composed of species typical of fine sediments that usually prevail in transitional environments (TEs). An overall high number of nematode species was recorded (55), belonging to 36 genera in 17 families. These values are highly comparable to those reported for other Italian TEs, but appear lower than those recorded in other European brackish-water systems, probably in relation to the low salinity range of Lake Varano. Forty taxa were identified up to species level, thus increasing the number of the nematode marine species known for the Italian coasts from 443 to 463, for the Adriatic basin from 310 to 313, and for the Southern Adriatic sector from 37 to 77. Considering the impor tance of this phylum in the assessment of ecological quality and the great vulnerability of the Adriatic Sea ecosystems, an intensification of sampling efforts should be planned, especially in the Central-Southern part of the basin. Such a plan would provide new insights into the biogeography of one of the most important components of the benthic domain and potentially yield new information about the climate warming effects on the Adriatic Sea.