Morphological and genetic analysis of freshwater sponges in Serbia

Abstract

Sponges in Serbian rivers and lakes have not been extensively studied. Hence, the aim of this work was to undertake an investigation of the distribution and phylogenetics of sponge species in Serbian waterbodies. A total of 83 localities on 17 rivers and 10 lakes have been investigated. Sponges (62 specimens) were found at 22 localities only. Sponge determination was done using a combination of morphological and genetic studies. Light microscopy and scanning electron microscopy were applied for spicule analysis while the D3 domain of 28S DNA was amplified and sequenced for genetic determination. The following five sponge species were identified: E. fluviatilis, S. lacustris, E. muelleri, T. horrida and E. fragilis. The sequence of the Serbian E. fragilis differed in two base pairs compared to Estonian E. fragilis (sequence obtained from the database of the National Center for Biotechnology Information, U.S. National Library of Medicine – NCBI), the previously deposited sequence on NCBI from Estonian E. fragilis. The sequence of T. horrida from our study is the first partial 28S sequence deposited for this species in the NCBI. A phylogenetic tree based on the 340bp sequences was also generated. It showed distinctive clades and was concordant with the results of the morphological analysis.