Investigation of Some Morphometric Characteristics of Neogobius melanostomus (Pallas, 1814) from Coast of Ordu (Eastern Black Sea)

Abstract

Morphological characters, such as body shape, morphometric measurements and meristic counts, have long been used in stock identification. Round goby (Neogobius melanostomus), of the family Gobiidae, is a benthic euryhaline species that is native to central Eurasia. Round goby invasion has had detrimental effects on native fish species and it is included in the list of 100 worst European invasive species. To the best of our knowledge, no previous studies had investigated the morphometric characterization of this species in the region, so the present study aims to give information about the morphometric characteristics of N. melanostomus in the coast of Ordu (Eastern Black Sea). A total of 16 morphological characters were measured using a caliper to the nearest ±0.001 cm. For the subsequent statistical procedures, the ratio of relative morphometric characters to total length (TB) was used. The samples examined were divided into three length groups: group I (10-14.9 cm; 18 samples), group II (15-19.9 cm; 26 samples) and group III (20-24.9 cm; 17 samples). With respect to coefficient of variation, first dorsal fin base length (D1T) was determined as the most variable character, whereas eye diameter (GÇ) was determined as the least variable character. Statistically significant correlations between POU, PA, BD2, D1T, D2T, PU, MxVY, KSY, and TB% were observed (P<0.05). Linear regression values indicated that, while standard length and total length had highest correlation (r=0.998), preorbital distance and total length had lowest correlation values (r=0.830).

Keywords

• fish morphology
• gobiidae
• round goby
• black sea