Key to the Genera and Species of Bathygadidae in Taiwan

1a. Chin barbel long, greater than half orbit diameter; elongated ray(s) in 1D, P and V; V 8 (rarely 9).............................................................. 2 ( Gadomus)

1b. Chin barbel usually absent, if present, length much less than half orbit diameter; usually no greatly elongated rays except in V, and if present, ray extremely fine distally and usually less than HL; V 8–10 (rarely 11)....................................... 4 ( Bathygadus)

2a. GR-I with blunt tips, 4–6+20–23............................................... 3

2b. GR-I with pointed tips, 6+22–26.................................... G. cf. multifilis

3a. Chin barbel about 3 times or less into HL; pyl. caeca 24–29................. G. magnifilis

3b. Chin barbel about 2 times into HL; pyl. caeca 95–134........................ G. colletti

4a. Gular membranes scaled; orbit width 1.1–1.2 times into interorbital................... 5

4b. Gular membranes wholly naked; orbit width 1.2–2.1 times into interorbital............. 6

5a. V 10 (rarely 11); barbel rarely present; pyl. caeca 12–19................... B. nipponicus

5b. V 9 (rarely 10); rudimentary barbel usually present; pyl. caeca 34–54........... B. garretti

6a.Head bones weak, skin thin and fragile; interorbital width 31–36% HL; pyl. caeca 10–18..................................................................... B. antrodes

6b.Head bones relatively strong, skin usually rather stout and thick; interorbital width 26–30% HL; pyl. caeca 20–22.................................................. B. furvescens