Bothus Rafinesque, 1810

Amaoka, Kunio & Ho, Hsuan-Ching, 2019, The lefteye flounder family Bothidae (Order Pleuronectiformes) of Taiwan, Zootaxa 4702 (1), pp. 155-215 : 168-169

Bothus Rafinesque, 1810

Bothus Rafinesque, 1810:23 . Type species: Bothus rumulo Rafinesque, 1810 .

Diagnostic features. Body round to elliptical in larger specimens. Tip of isthmus below middle of lower eye or slightly behind. Head profile, head spines, interorbital width, and length of pectoral-fin rays subject to sexual dimorphism and changing with growth. Both eyes separated by broad, concave space; interorbital width wider in males than in females or juveniles. Rostral, orbital and mandibular spines present in males. Large flap(s) from surface or posterior margin of both eyes in larger males, and sometimes in larger females.

Mouth small to moderately large; maxilla extends to, or somewhat beyond, anterior margin of lower eye. Teeth on both jaws uniserial or biserial, no canine-like teeth. Gill rakers short to moderately long, not serrated. Scales small, ctenoid on ocular side with row of moderate ctenii on posterior margin or cycloid; scales cycloid on blind side. Lateral line on ocular side curved above pectoral fin, absent on blind side.

Dorsal- and anal- fin rays simple and not elongate. Pectoral fin filamentous on ocular side in males, and sometimes also in females. Pelvic fin on ocular side starting at tip of isthmus, first ray on blind side opposite to fourth fin ray on ocular side. Vent on blind side, just before origin of anal fin, and urogenital pore on opposite side of vent. Caudal skeleton consisting of four plates including parhypural and three hypurals, without deep clefts. Four suborbital bones on blind side. First haemal spine distinctly enlarged; haemapophyses of abdominal vertebrae expanded, extending to neighboring haemapophysis at tip.

Remarks. Bothus closely resembles Tosarhombus in having a deep body and many scales on the lateral line. It differs from the latter in lacking yellowish white blotches along the head margin before both eyes, having the tip of the isthmus below the middle of the lower eye, four suborbital bones on the blind side, an enlarged first haemal spine and expanded haemapophyses in the abdominal vertebrae.