Brook trout (Salvelinus fontinalis)

Biology

Dorsal spines (total): 3 - 4; Dorsal soft rays (total): 8-14; Anal spines: 3 - 4; Anal soft rays: 8 - 14; Vertebrae: 58 - 62. Distinguished by the combination of dark green marbling on its back and dorsal fin and by the red spots with blue halos on its sides. Pelvic fins with axillary process; caudal nearly straight or with a shallow indentation. Color varies, but generally rather green to brownish on back, marked with paler vermiculations or marbling that extend onto the dorsal fin and sometimes the caudal; sides lighter than back, marked with numerous pale spots and some red spots, each of the latter surrounded by a blue halo; anal, pelvic and pectoral fins with a white leading edge followed by a dark stripe, the rest of the fins reddish. In spawning fish the lower sides and fins become red. Sea-run fish are dark green above with silvery sides, white bellies and very pale pink spots. Caudal fin

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