MASTERS OF THE WATER-BONY FISHES 



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fresh water, being favorite pets of small boys at the shore in summer. Killies 

 are among the hardiest of fishes, able to survive an amazing variety of salinities, 

 temperatures, and pollutions. They are found on both coasts of North and 

 South America and in Asia and Africa. 



Fig. 100. Couivwn killifish. 

 COMMON killifish: FiinduUis heteroclitiis 



Size: Averages 2 inches. Up to 6 inches. 



Distribution: Gulf of the St. Lawrence to the Gulf of Mexico. 



Identification: The males have pearly spots, and the females are a solid 

 olive-green. 



Habits: Killies are active, swarming little shore fish which eat almost anything, 

 including large numbers of mosquito larvae. They like weedy places along 

 the tide zone and are frequently trapped in high-sided tidepools. They are 

 not usually trapped in low-sided tidepools since they are able to climb out 

 of these and travel overland for ten feet or so to open shallow waters. Killies 

 lay eggs in weeds in spring. The male takes on orange hues at that time. 



Synentognaths : Suborder Synentognathi 



This group includes the gars, halfbeaks, and flying fishes. All of these fishes 

 are primarily silvery with bluish or greenish backs, and all are characteristic 

 of surface waters of warm temperate and tropical seas. The ventral fins are far 

 "back on the belly, and the lateral line is unique in that it follows the belly 

 outline. There is a marked tendency for these rapidly moving, active fishes 

 to take to the air, so most have an enlarged lower lobe of the tail fin, and 

 some also have enlarged pectoral and ventral fins, a trend culminating in the 

 flying fishes. 



A good rule of thumb for recognizing members of the group is that all either 

 possess winglike pectoral fins or elongate, beaklike jaws, and all have the dorsal 

 and anal fins far back on the body. The diets of synentognaths vary. Their eggs 

 have threadlike tufts on them which serve to anchor them to seaweed and to each 

 other. Most of them are schooling. They are cosmopolitan in warm seas. 



GARS, BILLFISHES, AND NEEDLEFISHES: Family Belonidae 



These are the largest of the synentognaths and the most voracious. The 

 elongate jaws and needlelike teeth are admirably suited for catching small fish. 



