Distribution of Sphaeriidae (Mollusca: Bivalvia) in relation to environmental variables in Northwestern Basin Streams in Türkiye

Ecology of the Sphaeriidae in Streams of Türkiye

Abstract

In this study, Sphaeriidae family was investigated in some freshwater systems of northwestern basin streams of Türkiye such as Karamenderes, Sarıçay, Mıhlı and Tuzla with respect to environmental variables. A standard multi-habitat sampling technique was applied to these streams at pre-selected stations using kick-net and surber-net. In addition, some water quality parameters such as temperature, pH, dissolved oxygen, conductivity, Oxidation Reduction Potential (ORP) were measured in situ using a multimeter probe. The taxa of Sphaeriidae were identified and counted in the laboratory under stereo microscope. The identified taxa were as follows, Musculium lacustre, Pisidium casertanum, P. nitidum, P. subtruncatum and P. sogdianum. Three of these species, namely P. casertanum, P. subtruncatum, P. nitidum, were widely distributed in the study area, while the rest were found in narrow ranges, especially P. sogdianum, which was found only in the Tuzla stream. The individual numbers of species in some streams were subjected to multidimensional scaling using SPSS 21.0. According to the multi-dimensional scaling (MDS), most of the water quality parameters influenced the distribution of most of the species. Water conductivity is the least effective parameter among the measured parameters, additionally P. casertanum and P. sogdianum showed distribution independent of water quality parameters.