The bay whiff, Citharichthys spilopterus
, is a relatively small flatfish of the family Bothidae
. Members of this group are known as "lefteye flounders" because both eyes and pigmentation are on the left side of the body. Bothids are also characterized by separate dorsal and anal fins and large eyes. As with other species of Citharichthys
, the lateral line of C. spilopterus
is nearly straight and the mouth is moderate in size (Robins & Ray 1986). The body is mostly brown, often with small, obscure spots. Unlike some other closely-related species, the opercle or gill cover on the blind side has no cirri. Pelvic fins are asymmetrical, with those of the eyed side located on the midline of the belly. Average fin ray and other meristic counts documented for some collected specimens are as follows: dorsal fin rays = 77-78; anal fin rays = 56-59; pectoral fin rays = 9-10; lateral line scales = 45; vertebrae = 33 (Castillo-Rivera & Kobelkowsky 1992, Ruiz-Carus & Rider 1998). Some species of flatfishes often exhibit reversal of the external and/or internal organs, with bothids appearing as dextral or righteye flounders. Such a process is rare for C. spilopterus
, but a few isolated cases of reversal in eye symmetry, pigmentation, the olfactory system, liver and intestines have been reported in Mexico, Florida and North Carolina (Castillo-Rivera & Kobelkowsky 1992, Ruiz-Carus & Rider 1998, Wilkins & Lewis 1971).