A new record of Ratan goby - Ponticola ratan (Nordmann, 1840) (Pisces: Gobiidae) in the Black Sea, Romanian coastal waters
Abstract
In August 2015 we managed to capture a specimen of ratan goby (Ponticola ratan) in the Romanian coastal waters of the Black Sea, near the locality of Sf. Gheorghe (Tulcea County). This is the 7-th signaling for this species in Romanian coastal waters. The previous 6 specimens were recorded in the period 1960-1993, between Mangalia (Constanţa County) and Sulina (Tulcea County). The species was identified by means of meristic characters (number of scales on medial line, number of spiny and soft rays), and morphological particularities (cycloid scales on the nape area and pectoral fin joint). Also, the measurements made, confirmed that the ratio between the head length and total length, which was 33% (TL=8.70 cm vs. Head Length=2.61cm). Another morphological character, specific to this species, is the lower jaw, which exceeds in length the upper jaw. Being a Ponto-Caspian endemite, with low population along the Bulgarian and Romanian coastline, we considered it important to point out this new record. Noting that, being known the trend of sporadic migration of this species, would not be excluded that global warming causes a shift from its normal distribution area, from northern and northeastern (Black Sea) to south-west. Therefore, future research may bring more notifications regarding this species in south-western area of the Black Sea
Keywords
