Seawatch: Scrawled Cowfish

Family Ostraciidea (boxfishes)

Cowfishes and trunkfish are commonly grouped under the heading of bonefishes because of their unusual shapes and their comparatively poor ability to swim.

Ostraciidea, derived from the Greek word for “shell,” alludes to the bodies of these fishes, which are encased in a hard, shell-like carapace. The carapace has holes that allow for the attachment of fins and the protuberance of the mouth, eyes and tail as well as the 11 pectoral fin rays. The count of 11 rays separates quadricornis from all other Bahamian trunkfishes, which have 12.

Color: Blue-green or black with a bluish cast. The long ventral stripe and the stripe above the eye are very blue. The fish can darken, grow pale or change color to match the background.

Size: Up to 18 inches
Food: Chiefly crustaceans and worms.

Distinguishing features: One horn is in front of each eye, and one horn projects rearward from each lower rear corner of the body armor. Trunkfish eyes can move independently. The tiny mouth is suitable only for small bits of food.

Habitat: These fish live in a wide range of territory, from grass beds to walls. They are found at depths up to 240 feet.

Correction: An alert reader caught a mistake in the June 16 Seawatch colum. The Copepod article erred in the conversion of 1 mm (0.39). This should have read 0.039. Thank you, Steven Brown.