Dorsal soft rays (total): 10-10; Anal soft rays: 8-9; Vertebrae: 41-42. Cobitis sakahoko can be diagnosed from its congeners from Japan by the combination of the following characters: lamina circularis at the base of the pectoral fin in adult males, rectangular plate with a neck in the mid-lower part (vs. beak shape or narrow in C. biwae; roundish in C. magnostriata, C. striata, C. minamorii, C. kaibarai and C. matsubarae; ambiguous inC. takatsuensis and C. shikokuensis); broad upper segments of the first branched soft ray (vs. narrow in C. striata, C. minamorii, and C. kaibarai); maxillary barbel length longer than the eye diameter (vs. same as the eye diameter in C. magnostriata, C. striata, C. minamorii and C. kaibarai); 14 segmented muscle plates between the base of the pectoral fin and the origin of the pelvic fin (vs. usually 13 in C. striata and C. kaibarai; usually 12 in C. minamorii); snout rather short, about 35% in HL (vs. rather long, ca. 40% in C. biwae, C. minamorii and C. matsubarae; long, over ca. 40% in C. magnostriata, C. striata, C, kaibarai, C. takatsuensis and C. shikokuensis); body pigmentation consisting of 1 mid-dorsal and 4 lateral rows of blotches with line L4 broad fine mesh-like line in adult females (vs. jagged or dotted line in C. biwae and C. matsubarae; jagged line in C. kaibarai; absent or irregular dotted line in C. magnostriata, C. takatsuensis and C. shikokuensis) and line L5 arranged into 8-13 oblong or ovoid blotches in both males and females (vs. striated in C. magnostriata; marbled streak in C. takatsuensis); upper spot at caudal-fin base jet black and size greater than the eye diameter (vs. comparable to the eye diameter in C. striata, C. kaibarai and C. takatsuensis; smaller than the eye diameter in C. minamorii and C. shikokuensis); lower spot at caudal-fin base black and size comparable or smaller than the upper spot (vs. ambiguous in C. striata, C. kaibarai, C. takatsuensis and C. shikokuensis). Cobitis sakahoko can be distinguishable based on the mtDNA cytb sequences (Ref. 117925).
Description: Dorsal fin iii, 7; anal fin iii, 5-6; pectoral fin i, 7-8; pelvic fin ii, 6 (Ref. 117925). |