Family LEPISOSTEIDAE 



THE GAR FAMILY 



The gars are a remnant of an ancient family. A number of species 

 are found in the southern United States, the West Indies, Central 

 America, and Mexico. At one time they were more widely distributed, 

 for fossil gars are known from Europe. 



They are all warm-water fishes. A species reaching a great size, the 

 alligator gar, Lepisosteus spatula Lacepede, is found in the Gulf States. 

 Gars are all distinguished by slender cyhndrical bodies and thin, long, 

 snoutlike jaws armed with sharp teeth. Teeth are present on the vomer 

 and palatines. The body is clothed with heavy diamond-shaped ganoid 

 scales covered by an enamellike substance, ganoin. The skeleton is 

 partly cartilage and partly bone. The swim bladder is connected with 

 the pharynx and may be used as a lung. The tail fin is of a modified 

 heterocercal type (page 59) . 



Key to Common Species of Family LEPISOSTEIDAE 



1. Beak long and slender; length of beak about 20 times least width 



Northern Longnose Gar, Lepisosteios osseus oxyurus Rafinesque 



Beak short and broad; length of beak about 5 1/2 times least width or less. .2 



2. Scales in lateral line usually 54-58; top of head with large round spots; body 



spotted; diffuse spots on fins Spotted Gar, Lepisosteus -jyroductus Cope 



Scales in lateral line usually 60-64; top of head without sj^ots; small round 

 black spots on fins Shortnose Gar, Lepisosteus platostorrms Rafinesque 



GENUS Lepisosteus Lacepede 



Three species of gars occur in the Upper Mississippi drainage, all 

 belonging to this genus. The single row of teeth in the upper jaw serves 

 to distinguish these species from the alligator gar found in the south, 



SHORTNOSE GAR 



Lepisosteus platostomus Rafinesque 



The shortnose gar (Figure 4D) is similar to the spotted gar except 

 that the shortnose gar has no spots on top of its head and has more 

 scales in the lateral line. It differs from the longnose gar chiefly in the 

 length of the jaw. The back is short and broad compared to that of 

 L. osseus oxyurus Rafinesque; the snout is broad and not much longer 

 (about 1.3) than the rest of the head. A very young fish has short jaws 

 and a wide black band on the sides. The scales in the lateral line usually 

 number 60-64. The shortnose gar seldom exceeds 2 or 3 feet in length. 



This species is distinctly southern in its distribution, occurring from 



81 



