The blackfish, or tautog (Tautoga onitis), is a fairly obscure member of the wrasse family. Its powerful jaws enable the fish to feed on hard-shelled invertebrates. Although the tautog leads a relatively unspectacular life in the northwestern Atlantic, it does belong to a rather interesting family.
The tautog belongs to the animal kingdom. In addition, it occurs within the following Linnaean taxonomic subgroups: Phylum Chordata, Class Actinopterygii, Order Perciformes, and Family Labridae. Members of the Chordata phylum are characterized by the presence of a notochord (6:23). In fish this nervous system structure is enclosed within a bony vertebral column. Class Actinopterygii comprises the ray-finned fishes (6:76). Tautogs also belong to an extremely diverse order. The order, Perciformes contains most vertebrate ocean life. Indeed, the order is the largest of all the vertebrates. It includes 18 suborders, 148 families, about 1,496 genera, and approximately 9,293 species (6:329-330).
Tautogs belong to the family Labridae, or the wrasse family. Like the order Perciformes, the family Labridae is also quite diverse. However, some characteristics which the wrasses do have in common include the following: (1) a protractile mouth; (2) separate jaw teeth which usually project outward; (3) dorsal fins with 8-21 spines (usually fewer than 15) and 6-21 soft rays; (4) large to moderate cycloid scales; (5) a continuous, uninterrupted lateral line; and (6) 23-42 vertebrae (6:386-387). The wrasses are marine fish; they occur in the Atlantic, Indian, and Pacific oceans (7:258). If a single behavior could be identified that was characteristic of the family, it might be their ability to sleep while buried under sand (5:137).
The wrasses also tend to exhibit great variation. Labridae is the second largest family of marine fishes, and the third largest perciform family (6:386-204). Moreover, it contains least 60 genera a...