THE NORTH AMERICAN CLEAR-WING MOTHS OF 

 THE FAMILY AEGERIIDAE 



By George P. Engelhardt 



DEFINITION AND CLASSIFICATION 



The moths of the family Aegeriidae, the so-called clearwings ("Glass- 

 fliigler"), are normally easily recognized by their general habitus, the nar- 

 row, mostly hyaline wings, and the dilated antennae, tufted at tips, although 

 these antennal characters do not hold for some of the genera {Bembecia, 

 Zenodoxus). Superficially they can be confused only with the so-called 

 bee moths of the genus Haemorrhagia and allies of the family Sphingidae 

 or with the moths of the family Syntomidae, from both of which the 

 Aegeriidae may at once be recognized by the very different venation and 

 especially by the locking system between the forewings and hindwings/ 

 described in the following diagnosis and not found outside the family. 



Tongue normally well developed, strong, naked, spiraled, but in some 

 genera aborted and not functional {Euhagena, Penstemonia). 



Eyes rather small, smooth, not hairy. 



Ocelli present. 



Antenna one-half to four-fifths as long as fore wing; in the numerically 

 largest groups dilated from the middle to the tip, ending in a small hair 

 tuft, but in Bemhecia and Zenodoxus tapering toward apex and not tufted 

 at tip ; the male in all groups with bipectination of various length on under- 

 side and with sensory areas especially on outer half; upperside smoothly 

 scaled ; the femaJes with simple, smooth antennae. 



Face, head, and thorax normally smooth, but rough-haired in a few 

 genera {Euhagena). 



Labial palpus well developed, more or less curved upright or obliquely 

 porrected; second joint smooth or with a more or less developed brush of 

 varying length ; terminal joint short, bluntly pointed, upright. 



Maxillary palpi rudimentary. 



Forewing normally partially hyaline, devoid of scales in certain areas ; 

 narrow-elongate, normally slightly dilated beyond middle, with bluntly 

 pointed apex and well-marked anal angle; normally with 12 veins present, 

 7 and 8 stalked, but in some genera with only 1 1 veins, 7 and 8 coincident 

 (Calesesia) or 10 and 11 fused; veins 2, 3, 4, 5, and 6 usually well sepa- 

 rated and nearly parallel, but 2 and 3 stalked in Zenodoxus and 4 and 5 

 connate in Signaphora ; 9 and 10 stalked in Sylvora; Ic absent ; la entirely 



1 The one diagnostic character of the family. 



