Notes on the Aquatic Hemiptera. 



Under this head are treated those families of Hemiptera 

 which have become adapted to an aquatic life. Like a number 

 of families of the Coleoptera they not only rear their young 

 in the water but continue to dwell therein during adult life. 



Family BELOSTOMATID^ Leach 1815. 

 A. Taxonomy of Belostomatid^. 



Family Characteristics. Large, flat, brown bugs, with hind legs ciliated 

 and flattened for swimming. They bear short, flat, strap-like appendages 

 at tip of the abdomen. These are retractile. 



Ocelli are lacking. The antenna are hidden beneath the eyes, four- 

 segmented, and the outer segments produced on one side. The tarsi are 

 two-segmented. In the American forms, the fore tarsi bear but a single 

 claw each, the other limbs two each. The fore legs are raptorial, the 

 femora enlarged, and the tarsal segment broadly joined to the tibia. The 

 middle and hind limbs are natatorial, the tibia and tarsi being somewhat 

 flattened, and the hind limbs, especially, ciliated. The fore wings possess 

 reticulated membranes. These large insects leave the water at dusk and 

 are often noted at the electric lights, to which they are attracted. Thus 

 their common name "electric-light bugs." They are also known as "giant 

 water bugs." 



Historical Review. To those of us who gained our names of water bugs 

 from text books of a few years back, it was most vexing to learn that 

 the nomenclature to which we had been exposed was wrong — so badly 

 wrong that we were forced to learn that Zaitha was Belostoma, that 

 there was no Zaitha, and that Belostoma was Lethocenis. We now have 

 it straight. The genus Belostoma was created by Latreille, 1807, for a 

 small Belostomatid. It was Amyot and Serville, 1843, who gave us the 

 name Zaitha, which means "olive," and which has so generally been ap- 

 plied to our small Belostomatids. The type they used, stolli, however, 

 turned out to be Latreille's testaceo pallidum. So we must forget Zaitha. 

 Meyr, 1852, founded the genus Lethocerus for some large Belostomatid. 

 These differ from Stal's Benacus in possessing a grooved fore femur. 



Van Duzee lists four genera for America north of Mexico. They are 

 Belostoma, Latr., Ahedus Stal., Lethocenis Mayr, and Benacus Stal. 



They may be separated by the following key to genera. 



KEY TO GENERA. 



A. Mesothorax with a strong midventral keel, membrane of hemelytra 

 reduced. Ahedus. 



AA. Mesothorax without midventral keel. Membrane of hemelytra not 

 reduced. 



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