Slatkovodni sunđeri (Porifera, Spongillidae) zapadnog Balkana i Panonske nizije: morfološko-genetička studija

Abstract

Uvod Slatkovodni sunđeri predstavljaju zanimljivu grupu bentosnih organizama sa važnom ulogom u akvatičnim ekosistemima. Ciljevi ove studije bili su identifikacija različitih vrsta slatkovodnih sunđera u lentičkim i lotičkim ekosistemima Zapadnog Balkana i Panonske nizije, procena njihove rasprostranjenosti u ispitivanom regionu, kao i analiza distribucije vrsta u odnosu na parametre okruženja - fizičko-hemijske karakteristike vode i na prisustvo zagađivača. Materijali i metode Istraživanjem je obuhvaćen 171 lokalitet na Dunavu i Savi, kao i na rekama i jezerima Srbije, Severne Makedonije i Crne Gore. Identifikacija sunđera izvršena je svetlosnom i skenirajućom elektronskom mikroskopijom skeletnih elemenata (spikula) dobijenih nakon digestije sunđera u HNO3. Determinacija sunđera urađena je i putem genetičke analize, koja je podrazumevala izolaciju DNK, zatim PCR amplifikaciju 3D regiona 28S rDNK i njeno sekvenciranje. Podaci su statistički obrađeni u SPSS. Rezultati Ukupno je u toku istraživanja prikupljeno 168 primeraka sunđera. U istraživanom području identifikovano je sledećih pet vrsta (poređanih po opadajućoj učestalosti), od šest, koje trenutno žive u srednjoj Evropi: Ephidatia fluviatilis, Spongilla lacustris, Ephidatia muelleri, Trochospongilla horrida i Eunapius fragilis. Sunđeri su zabeleženi na 25% pretraženih lokaliteta. Abundanca , učestalost nalaza i biomasa sunđera bili su niski. Sekvenciranjem je otkriveno pet novih haplotipova. Zaključci Pet identifikovanih vrsta slatkovodnih sunđera su u području istraživanja pokazali neravnomernu distribuciju i nisku zastupljenost. Analizirane fizičko-hemijske karakteristike kao ni zagađivači nisu imali veći uticaj na distribuciju Porifera.

Introduction Freshwater sponges represent a peculiar group of benthic organisms with an important role in aquatic ecosystems. The aims of this study were to identify different species of freshwater sponges in lentic and lotic waterbodies of Western Balkan and Pannonian Plain and to assess their overall distribution in the studied region. Their distribution in relation to physico-chemical characteristics of the water bodies and to the presence of pollutants was assessed as well. Materials and Methods The investigation covered 171 localities on the Danube and Sava, and on rivers and lakes of Serbia, Northern Macedonia and Montenegro. Sponge identification was done by light and scanning electron microscopy of skeletal elements (spicules), obtained after sponge digestion in HNO3. Sponge identification was also done by genetic analysis, including sponge DNA isolation followed by PCR amplification of the 3D region of 28S rDNA and its sequencing. Data were statistically analyzed in SPSS. Results During this research 168 samples of sponges have been collected. In the studied area, the following five Porifera species (ordered by decreasing incidence) have been identified, out of six presently extant in Central Europe: Ephydatia fluviatilis, Spongilla lacustris, Ephydatia muelleri, Trochospongilla horrida and Eunapius fragilis. Only 25% of explored localities harbored sponges. Sponge abundance and biomass were also very low. Sequencing revealed four new haplotypes. Conclusions Five identified freshwater sponges proved to be scarce and unevenly distributed along the explored region of the Western Balkan and Pannonian plain. Evaluated physico-chemical characteristics and pollutants did not seem to have a major impact on Porifera distribution.