A NEW LOCALITY FOR THE ENDEMIC Gobio sakaryaensis TURAN, EKMEKÇİ, LUSKOVA & MENDEL, 2012 IN THE MARMARA REGION (TURKEY) AND THE LENGTH-WEIGHT RELATIONSHIP OF THE SPECIES

One of the endemic freshwater fish species of Turkey, Gobio sakaryaensis Turan, Ekmekçi, Luskova & Mendel, 2012 is reported for the first time from the Lake Sapanca Basin. A total of 18 G. sakaryaensis specimens was captured using electroshocker on October 18, 2008 and February 5, 2009 from the Maşukiye Stream (western Lake Sapanca). This finding has increased the number of the fish species living in the basin. The value of parameter b in the LWR equation was calculated 3.176.The last comprehensive checklist of the freshwater fishes of Turkey has reported that a total of 409 fish species inhabit in the freshwater systems and 194 of them is endemic to Anatolia (Çiçek et al., 2018). The genus, Gobio is known to be one of the richest genera because of its adaptations to different habitats (Turan et al., 2016). Recently, a total of 14 species belonging to the genus Gobio was recognised from Turkish inland waters, and except Gobio bulgaricus and Gobio kovatschevi all of these species are the Anatolian endemics (Naseka et al., 2006; Kottelat and Freyhof, 2007; Turan et al., 2012; Turan et al., 2016; Turan et al., 2017; Turan et al., 2018). Gobio sakaryaensis is one of the endemic gudgeons and it was described from the Tozman and Porsuk streams in the Sakarya River drainage (northwestern Anatolia, Black Sea basin) (Turan et al., 2012).