Head Pores - cephalic canal system with pores B',D,F,H'
Scales - lateral scale rows 80-100; irregular rows of small scales, largest on caudal peduncle, smaller towards head; no scales under pelvic fins; slightly ctenoid in juveniles cycloid in adults; a few predorsal scales along midline; in a line the width of 1/2 eye dia. Extending forward the length of D2 base
Fins - D1 - IV-VIII; D2 - 10-17; pectoral - 18-23; anal - 9-16; caudal truncate, corners rounded
Head - Maxilla extends to preopercle or beyond in adults; tongue emarginate or notched; interorbital wider than eye diameter; upper and lower jaw with teeth small, conical, inclined backwards, in a broad band of 4-5 rows, bands narrow posteriorly, end at a vertical with anterior margin of eye
Papillae - small and difficult to count
Color - Body lightly brown, sometimes almost yellow, other times nearly black; sometimes five irregular black blotches on back down to middle of sides, a sixth blotch across occiput; a series of smaller blotches along horizontal septum alternate with large blotches, occasionally form continuous line; black blotch on end of caudal peduncle often extends onto base of caudal fin rays. Head light brown, frequently black on snout, lip, upper one third of opercle, and under eyes; cheek sometimes with reticulations of darker brown; entire head sometimes black; throat and chin yellow to dusky, chin often dark brown or black. Pectoral fin dusky, lighter toward margin, without barring; upper half of base dark brown. Pelvic fins yellow, with or without scattered, contracted chromatophores. Both dorsal fins and anal fins usually heavily pigmented, almost black, dusky in pale specimens, margins white. Second dorsal fin rarely with traces of two to three horizontal stripes. Anal fin sometimes lighter proximally. Caudal fin dusky, often lighter at posterior margin (Barlow 1961)
Distribution - Tomales Bay (northern CA) to Gulf of California
Habitat - tidal flats, bays, coastal sloughs; prefers mud bottom in shallow water