Neuroptera 331 



Order neuroptera 



METHODS OF COLLECTING AND REARING NEUROPTERA 



Roger C. Smith, Kansas State College 



CHRYSOPIDAE (Lace-wings, aphis-lions) 



ADULT chrysopids may be most successfully collected at lights in the 

 . early evening and by sweeping vegetation or beating bushes and 

 trees during the days (Smith, 1922, 1934). Gravid females have dis- 

 tended abdomens and the more common species deposit their stalked 

 eggs very readily in captivity. It is desirable to line the bottle or vial 

 with leaves or paper so that the eggs will be deposited on them. The 

 leaves or paper may then be removed and cut in pieces with an egg to 

 a piece for placing in small individual vials. This is desirable because the 

 larvae are cannibalistic. 



Adult chrysopids require food. Place leaves with a few aphids on 

 them or a pledget of cotton made wet with water or dilute sugar solution 

 in the bottle. The vials or bottles must not be so moist as to allow drop- 

 lets of water to form because the wings will be caught in the water and 

 the adults will die. Adults may be kept for a week or more in a bottle, 

 and eggs may be deposited over most of the period. The food should 

 be changed daily. The rarer the species of chrysopid the greater the re- 

 luctance to oviposit and live satisfactorily in confinement. Hibernating 

 prepupae and adults may be brought into the laboratory after they 

 have experienced a cold stimulus. They will then develop or lay eggs 

 during the winter months. 



Eggs of this family may be collected in the normal habitat of the 

 species. Eggs of the tree-inhabiting species may be taken on leaves, 

 where they occur generally on the under side, and on the trunks and 

 limbs of the tree. Those lace-wings inhabiting low vegetation lay their 

 eggs on the under-side of leaves (generally), or on the stems. 



Larvae may be taken by sweeping and beating. Use a regular beating 

 or sweeping net and examine the contents carefully. Practice is required 

 to see them readily in a mass of net contents. Larvae often occur in or 

 near aphid colonies, in aphid-curled leaves, and under or on the bark of 

 trees infested with aphids, psyllids, some scale insects, and mealybugs. 



Cocoons may be collected by pulling off pieces of bark on oak and 

 maple trees, especially during the winter or spring. Cocoons should be 

 placed in large bottles in which there are some twigs or vegetation so the 

 pupae may climb up, shed their pupal molts and spread their wings. 

 Otherwise many reared adults will have crumpled wings. 



While chrysopid adults and larvae feed on all kinds of aphids, the 

 smaller green aphids are more satisfactory for feeding than the larger 



