診断 |
Distinguished from its congeners by the following characters: distance between anterior and posterior nares exceeds diameter of posterior ones, upper lip with deep median incision, sometimes completely dividing it into two parts; lower lip has extensive lateral expansions; weakly developed processus dentiformis always present; lateral line complete; manubrium well-developed; free air-bladder portion reduced or absent; vertebrae 42-46; anterior fontanelle or neurocranium present; parietal and pteroticum in contact; basibranchial-4 and infrapharyngobranchials-3 absent (Ref. 57754). |