204 



Usinger: Hemiptera 



Fig. 7:16. o, Be/ostoma flumineum Say, Dav 

 Usinger); b, Abedus hungerfordi De Carl 

 (R. L. Usinger). 



feint" for varying periods which averaged 16.4 minutes 

 in five successive experiments involving six belo- 

 stomas (Severin and Severin, 1911). 



Another curious habit, namely, the forceful ejection 

 of fluid from the anus, has been noted when the bugs 

 have been held captive out of water (Harvey, 1907). 

 This fluid may be responsible for the odor noted by 

 some observers. 



Lethocerus indicus L. & S. is boiled in salt water 

 and eaten by the Cantonese and other Asiatic peoples. 

 Specimens may be purchased in food shops in China 

 and in Chinatown in San Francisco. 



Stridulation has not been verified in this family 

 but Hungerford (1925) noted "a wheezing noise" 

 made by Benacus griseus, and Harvey (1907) reported 

 a "soft chirping noise" for Abedus "macronyx." 



Flight. — Hungerford (1925) documents the well- 

 known propensity of Benacus and Lethocerus to fly 

 to electric lights. At Lawrence, Kansas, 44 males 

 and 57 females were taken on May 5, 1920; 9 males 

 and 7 females on May 8; 22 and 29 on May 9; 9 and 12 

 on May 21; and 29 and 16 on May 22. All these figures 

 apply to Benacus griseus but 10 males and 1 female 

 of Lethocerus americanus were taken at the same time. 



Habitat. — Ponds and quiet pools in streams are the 

 favorite haunts of belostomatids. In spite of their 

 large size, these bugs are not conspicuous because 

 they commonly rest at the surface in trash or mats 

 of vegetation. They rest with the body extending 

 obliquely downward and the tip of the abdomen slightly 

 above the surface film. 



Yolo County, California, July 9, 1932 (R. L. 

 Walnut Creek, Contra Costa County, California 



Feeding. — Belostomatids are clearly the masters of 

 their immediate environment. They capture and suck 

 dry a variety of insects and other aquatic arthropods 

 as well as tadpole's and fish. Large bugs have been 

 known to destroy fish several times their size (Dim- 

 mock, 1886). Some attention has been given to control 

 methods in pond fish culture in the United States and 

 in China. 



Respiration. — Belostomatids obtain air by breaking 

 the surface film with the short, straplike appendages 

 at the tip of the abdomen. Each of these flaps has a 

 spiracular opening near the base which connects with 

 a main longitudinal tracheal trunk. Air is admitted to 

 the space between the hemelytra and the dorsal 

 surface of the abdomen and appears as a large silvery 

 bubble when the bug dives below the surface. 



Life history. — Like most water bugs, belostomatids 

 overwinter as adults. Eggs are laid in the spring and 

 early summer. Benacus and Lethocerus lay masses of 

 one hundred or more eggs on supports above the 

 water, for example, on cattail stalks. The eggs are 

 glued at the posterior ends and project outward. 

 They are arranged in rows and are contiguous. They 

 increase in size as they develop, the dimensions for 

 Benacus griseus being 4.5 mm. long and 2.25 mm. in 

 diameter when laid and 6.57 mm. long twelve days 

 later. The egg surface is hexagonally reticulate, and 

 the color becomes progressively darker and longi- 

 tudinally striped with brown as development proceeds. 

 The incubation period has been reported as one to 

 two weeks. Hatching takes place by a breaking open 



