Bathygobius, Bleeker, 1878

Schwarzhans, Werner, Klots, Oleksandr, Ryabokon, Tamara & Kovalchuk, Oleksandr, 2022, A rare window into a back-reef fish community from the middle Miocene (late Badenian) Medobory Hills barrier reef in western Ukraine, reconstructed mostly by means of otoliths, Swiss Journal of Palaeontology (18) 141 (1), pp. 1-35 : 14

Bathygobius ? sp.

Figure 5j

Material 1 otolith, Kozatskyi Yar, NMNHU-P PI 2548.

Description Te single, rather well-preserved small otolith of 1.5 mm in length is characterized as follows. OL:OH = 1.05; OH:OT = 2.5. Ventral and posterior rim straight, meeting in orthogonal angle; postdorsal projection not expanded. Anterior rim slightly inclined at about 80°, straight. Dorsal rim with obtuse, depressed predorsal angle, ascending to broad postdorsal angle followed by short, slightly declining postdorsal section.

Inner face slightly convex, with large, wide, slightly deepened, distinctly inclined (20°) centrally positioned sulcus with moderate ostial lobe and no subcaudal iugum. OL:SuL = 1.55; SuL:SuH = 1.85. Ventral furrow deep and distinct, curving more regular than ventral rim of otolith and thus clipping pre- and postventral angles. Dorsal depression wide and deep with distinct crista superior toward sulcus and dorsally open. Outer face more convex than inner face, smooth.

Discussion Te large and wide sulcus of this otolith is quite remarkable and resembles the morphotype found in otoliths of extant species of Bathygobius (see Lin & Chang, 2012 for figures). However, extant Bathygobius otoliths are usually thinner than the one described here. For this reason and given the distance from the site, where the otolith was obtained and the actual distribution range of the genus (the Indian Ocean, tropical Pacific, and tropical western Atlantic), our generic allocation remains tentative.

Figures

Fig. 5 Otoliths of Odondebuenia, Parenypnias and Bathygobius?: a–d Odondebuenia agiadiae Schwarzhans et al., 2020a, 2020b, a (reversed) Kozatskyi Yar,NMB P1219, b (reversed), d Kozatskyi Yar, NMNHU-P PI 2569, c (reversed) Mlyntsi, NMNHU-P PI 2570.e–h Parenypnias inauditus n. gen. et n. sp., f holotype, Kozatskyi Yar,NMNHU-P PI 2550,e, g (reversed) Shydlivshchyna, NMB P1207, h Žižkov 1 well (1616–1622 m), DGS MU-0395. i Parenypnias kiselevi n. gen. et n. sp., holotype, Mlyntsi,NMNHU-P PI 2574. j Enypnias seminudus (GÜnther, 1861), Recent,USNM 407784,13° 22′ N 87° 52′ W.k Gobiosoma bosc (Lacépède,1800), Recent (reversed), LACM coll. Fitch, off Rappahannock. l Bathygobius? sp. (reversed), Kozatskyi Yar, NMNHU-P PI 2548