Table 2. Overview of the extant genera of the Butidae with number of species, zoogeographic distribution and habitats (after [7], [49], [52], [55]) and selected morphological differences that separate them from †Lepidocottus.

Genus and number of species	Standard length (in cm)	Zoogeography	Habitat	Selected differences vs. †Lepidocottus
Bostrychus Lacepède (9)	7.5–22	Indo- & West Pacific, Asia, East Atlantic	Estuarine	Scales cycloid, 90 or more in longitudinal row
Butis Bleeker (6)	8–14	Indo- & West Pacific, Asia	Marine to estuarine	Lower jaw longer than upper jaw, one epural
Incara Rao (1)	<6	India	Estuarine	Pterygiophore formula 3-II II I I
Kribia Herre (4)	<3	East Atlantic	Freshwater	One epural
Ophiocara Gill (2)	20–27	Indo- & West Pacific, Madagascar	Estuarine	33–42 longitudinal scales
Oxyeleotris Bleeker (16)	4–65	West Pacific, Asia, Oceania	Estuarine, freshwater	>60 longitudinal scales
Odonteleotris Gill (3)	Up to 28	West Pacific, Asia	Estuarine, freshwater	90 or more longitudinal scales
Parviparma Herre (1)	n.a.	Philippines	Freshwater	Pterygiophore formula 4-III II I I
Pogoneleotris Bleeker (1)	n.a.	Malaysia	Estuarine	Scales ctenoid plus cycloid body scales, eyes reduced,
Prionobutis Bleeker (2)	5–12	West Borneo, Papua New Guinea	Estuarine, freshwater	Pterygiophore formula 3-II II I I
Typhleotris Petit (2)	<3	Madagascar	In caves	Blind, small size

Note that Odonteleotris, Parviparma and Pogoneleotris are not listed among the valid genera of Butidae in [21]; their systematic affinities are in need of further investigation. n.a. = data not available.