Most wrasses are quite small, usually below 20 cm. The smallest species, Minilabrus striatus of the Red Sea, reaches a maximum length of only 4.5 cm. The genera Pseudocheilinus and Doratonotus contain several other dwarf wrasses. One species, Conniella apterygia, is so small that it lacks even pelvic fins and a supporting skeleton. The largest wrasse, Cheilinus undulatus, can reach a length of about 2.3 m and weighs more than 150 kg. Wrasses are most easily identified by their pointed snouts and prominent canine teeth in the front of the jaws, which often project forward. Wrasses characteristically have a protractile mouth, cycloid scales , and a single continuous dorsal fin lacking an obvious notch between the soft and spiny portions. The lateral line may be continuous or interrupted. (Click here to see a fish diagram).
Wrasses display myriad colors and shapes. Razorfishes are elongate and laterally compressed, while members of Cheilinus, Choerodon, and many of Bodianus are large and stocky. However, most are elongate and tapered at both ends, often referred to as “cigar-shaped.” Cigar-shaped fishes are found in the genera Thalassoma, Halichoeres, and Labroides. Often, there is considerable diversity of colors and shapes within individual species. As in parrotfishes, some wrasses progress through “phases” (see Reproduction: Mating Systems), and each phase corresponds with a change in morphology (shape and color). Dominant males (and sometimes females) are the most distinctly colored, with complex patterns of red, yellow, green, blue and black. Subordinate males and females are smaller than dominant individuals and are often drab-colored with cryptic patterns. Juveniles range in coloration from bright yellow and orange to drab gray and brown, and some have camouflaging patterns. (See Reproduction: Mating Systems for details). Some wrasses exhibit sexual dimorphism.
Other Physical Features: ectothermic ; bilateral symmetry ; polymorphic
Sexual Dimorphism: male larger; sexes colored or patterned differently; male more colorful; sexes shaped differently
- Moyle, P., J. Cech. 2000. Fishes: An introduction to ichthyology – fourth edition. Upper Saddle River, NJ: Prentice-Hall.
- Thresher, R. 1984. Reproduction in Reef Fishes. Neptune City, NJ: T.F.H. Publications.