It has 7–8 dorsal spines, 14–18 dorsal soft rays, a single anal spine and 12–16 anal soft rays.
This species is distinguished from its relatives in Neogobius based on multiple characteristics. B. gymnotrachelus has diagonal bars of irregular position and shape. The first branched ray of second dorsal is about as long as its penultimate ray. It lacks scales on the midline of its nape, anterior to its preoperculum. It has a pelvic-disc fraenum with small rounded lobes and length less than 1/6 of width at base. It has 54–62 + 2–3 scales in midlateral series. The posterior part of first dorsal has no black spot.
The racer goby inhabits but is non-indigenous in the rivers of the Baltic basin, including the Bug and Vistula.[5][6][7] It was also introduced in the Middle Danube, in Hungary.[8] The westernmost locality of this species range is the German sector of the Danube River, where this fish occurred first in 2011.[9] The information about the introduction of this species to the Lower Rhine River[10] is considered erroneous.[9]
^Stepien CA, Tumeo MA (2006). "Invasion genetics of Ponto-Caspian gobies in the Great Lakes: a "cryptic" species, absence of founder effects, and comparative risk analysis". Biological Invasions. 8: 61–78. doi:10.1007/s10530-005-0237-x.
^Neilson ME, Stepien CA (2009). "Escape from the Ponto-Caspian: Evolution and biogeography of an endemic goby species flock (Benthophilinae: Gobiidae: Teleostei)". Molecular Phylogenetics and Evolution. 52 (1): 84–102. doi:10.1016/j.ympev.2008.12.023.
^Danilkiewicz Z (1996).『Babka łysa (gołogłowa), Neogobius gymnotrachelus (Kessler, 1857) (Perciformes, Gobiidae) - nowy, gatunek w ichtiofaunie zlewiska Morza Bałtyckiego』[Bald goby, Neogobius gymnotrachelus (Kessler, 1857) (Perciformes, Gobiidae) - a new species in the ichthyofauna of the Baltic Sea basin]. Komunikaty Rybackie [Fishing Communications] (in Polish). 2: 27–29.
^Kostrzewa J, Grabowski M, Zięba G (2004). "Nowe inwazyjne gatunki ryb w wodach Polski" [New invasive fish species in Polish waters] (PDF). Archives of Polish Fisheries (in Polish). 12 (suppl 2): 21–34. Archived from the original(PDF) on 2009-02-19.
^Jaroszewska M, Dabrowski K, Wilczyńska B, Kakareko T (2008). "Structure of the gut of the racer goby Neogobius gymnotrachelus (Kessler, 1857)". Journal of Fish Biology. 72 (7): 1773–1786. doi:10.1111/j.1095-8649.2008.01870.x.
^Guti G (2004). "First record of Racer Goby Neogobius gymnotrachelus (Pallas, 1811) in the Hungarian section of the Danube". Opusc. Zool. 35. Budapest: 83–84.
