MIROGOBIUS 91 



*. Body nearly or entirely naked. 



uu l . Posterior third with minute cycloid scales, the rest naked; eyes 

 minute, under the skin; dorsal and anal very long, continuous 



with caudal Caragobius. 



uu 1 . Entirely naked or a few barely visible scales at posterior end, 



dorsal and anal not continuous with caudal. 

 vv 1 . Teeth in lower jaw tricuspid; an erect crest from tip of snout 



to nape Itbaya. 



vv*. Teeth all simple; no crest on head. 



urw 1 . No symphysial canines in lower jaw; body spindle- or 



tadpole-shaped Gobiosoma. 



ww*. Canines behind symphysis of lower jaw. 



xx 1 . Body very small, elongate, of ordinary shape; teeth in one 



row; first dorsal spines four or five Mirogobius. 



xx". Body very deep, oval, much flattened laterally; teeth in 

 two or more rows; first dorsal spines six.... Gobioddn. 

 a 1 . Ventral fins very short, nearly circular, cup-shaped, more or less adher- 

 ent to belly; teeth unlike those of other gobies; in upper jaw tri- 

 cuspid under microscope, or bicuspid or clavate; lower lip with a row 

 of movable, more or less horizontal teeth; lower jaw with symphysial 

 canines and a row of hooked teeth or canines. 

 yy*. Teeth of upper jaw more or less club-shaped, blunt, fixed, in one 



row; scales 30 to 40 Microsycidium. 



yy*. Teeth of upper jaw movable, curved, tricuspid in Philippine species; 

 scales 50 to 85 Sicyopterus. 



Genus 20. MIROGOBIUS g. nov. 



The body laterally compressed, with a robust blunt head, the 

 dorsals far apart; the mouth large, oblique, with a single row 

 of long, stout, widely spaced, curved teeth in each jaw and a 

 pair of postsymphysial canines in lower jaw, behind the outer 

 row; in one species the m'ales only have canines; the tongue 

 notched; the skin is naked or there may be a few tiny cycloid 

 scales at or near base of caudal fin; the caudal and pectoral 

 both rounded, shorter than head; the ventrals narrow, pointed, 

 shorter than head, not adherent to belly, with a broad frenum 

 which forms a subtubulate sucking disk ; the gill openings large, 

 extended forward along throat, the isthmus narrow, branchios- 

 tegals five. Dorsal IV or V, 1-7 ; anal I, 8 to 10. 



In the combination of characters found in its fins, teeth, 

 and scaleless body this genus stands alone. Type of genus M. 

 stellatus sp. nov. 



Mirus, wonderful. 



Key to the Philippine species of Mirogobius. 



a 1 . Anal I, 10; a pair of post-symphysial canines in lower jaw of both 

 sexes ; color darkened by many black stellate spots M. stellatus. 



