174 



UNITED STATES NATIONAL MUSEUM BULLETIN 207 



86. Genus Acroncosa Barnes and McDiumough 



Acroncosa Barnes and McDunnough, Canadian Ent., vol. 49, 

 p. 404, 1917. (Type of genus: Acroncosa albiflavella Barnes 

 and McDunnough.) 



Tongue well developed. Antenna simple except for 

 a few minute thomlike projections on base of shaft of 

 the male (no appreciable sinus or scale tuft); very 

 shortly and weakly pubescent in both sexes. Labial 

 palpus short, slender, oblique, third segment shorter 

 than second, blunt, projected slightly forward; not 

 reaching to height of vertex. Maxillary palpus 

 squamous. Forewing smooth; 11 veins; vein 2 from 

 before but near lower outer angle of cell; 3 from the 

 angle; 4 and 5 separated at base; 6 from below upper 

 angle of cell, straight; 8 and 9 stalked for half or a 

 trifle over half their lengths; 10 from the cell, separated 

 at base from 8-9 and not approximate to its stalk; 

 male without costal fold. Hind wing with vein 2 from 

 well before lower outer angle of cell; 3 from the angle 

 and approximate to 4 for a short distance beyond the 

 angle; 4 and 5 contiguous or anastomosed beyond the 

 angle for about half their lengths (superficially, on 

 imdenuded specimens, they appear long stalked) ; 7 and 

 8 closely approximate for a short distance from cell; 

 cell less than half the length of wing; discoceUular vein 

 cm^ed, considerable produced outwardly at lower angle. 

 Eighth abdominal segment of male with a pair of ventro- 

 lateral hair tufts (the hairs somewhat flattened). 



Male genitalia with uncus broadly triangulate, its 

 apex bluntly pointed. Transtilla incomplete, its ele- 

 ments moderately sized, irregularly triangulate plates. 

 Harpe simple; costa sclerotized nearly to apex, not 

 produced. Anellus a shallow U-shaped plate with small 

 lateral lobes. Aedeagus long, stout; penis armed with 

 masses of spines varying from long (one-third the length 

 of aedeagus) to minute. (Figs. 418c-e show the shape 

 and character of the longer spines, greatly enlarged.) 

 Vinculum stout, longer than greatest width, tapering 

 to truncate terminal margin. 



Female genitalia with signa consisting of two small, 

 opposed, strongly spined, round plates; bursa otherwise 

 membranous except for a thickening of the lobe giving 

 off the ductus seminalis; ductus bursae long, slender, 

 tubular, unsclerotized except for a couple of weak spine 

 clusters near junction with bursa; genital opening 

 simple; ductus seminalis from bursa near its junction 

 with ductus bursae. 



Foretibia with a long inner and short outer claw. I 

 shoidd suspect this character to be merely specific 

 except that it is equally developed in both sexes of both 

 species of the genus. 



361. Acroncosa albiflavella Barnes and McDunnough 



FiGUBEs 35, 418, 907 



Acroncosa albiflavella Barnes and McDunnough, Canadian Ent., 

 vol. 49, p. 405, 1917.— McDunnough, Check list. No. 6151, 

 1939. 



Forewing white; the transverse white lines lost in the 

 ground color; antemedial line indicated only by a broad 



oblique inner orange band extending from inner margin 

 to costa; subterminal line indicated by a similar, 

 narrower, sinuate, outer orange band, the latter termi- 

 nating at costa in a small blackish spot; a well-con- 

 trasted black discal dot at lower, outer angle of cell and 

 a smaller black dot on inner margin of the subbasal 

 orange band at vein lb; on same specimens a few 

 widely scattered black scales on the white ground color 

 of median area. Hind wings whitish with a very faint 

 ocherous or smoky tint; the veius not appreciably 

 darkened. Alar expanse, 18-21 mm. 



Genitalia as given for the genus. 



Type locality: Loma Linda, San Bernardino Coun- 

 ty, Calif, (type in USNM). 



Food plant: Unknown. 



Distribution: California, Loma Linda (July, Aug.), 

 Mona Lake (July) . 



362. Acroncosa albiflavella castrella Barnes and McDunnough 



Acroncosa albiflavella castrella Barnes and McDunnough, 

 Canadian Ent., vol. 49, p. 405, 1917. 



A local race of albiflavella differing only in having a 

 stronger peppering of black scales iu the median area of 

 forewing. Alar expanse, 20-22 mm. 



Genitalia Hke those of typical albiflavella. 



Type locality: Fort Wingate, N. Mex. (type in 

 USNM). 



Food plant: Unloiown. 



Distribution: New Mexico, Fort Wingate (July, 

 Aug.). 



Apparently a distinguishable local race, but can be 

 identified only by locality label and a somewhat 

 stronger dusting of black scales on forewing. 



363. Acroncosa similella Barnes and McDunnough 



Acroncosa similella Barnes and McDunnough, Canadian Ent., 

 vol. 49, p. 405, 1917.— McDunnough, Check list No. 6152, 

 1939. 



Forewing similar to albiflavella except: A much 

 heavier peppering of black scales on forewing; orange 

 inner border of antemedial line extending only from 

 inner margin to top of ceU; a concentration of black 

 scaling forming a more or less broken line along outer 

 margin of the antemedial line; a similar black Une 

 inwardly borderiug the subterminal line; basal, median, 

 and outer areas dusted with black scales. Alar expanse, 

 21-26 mm. 



Genitaha like those of albiflavella. 



Type locality: Pyramid Lake, Nev. (type in 

 USNM). 



Food plant: Unknown. 



Distribution: A^e/ra^Za, Pyramid Lake; Z7toA, Eureka 

 (June). 



Not structurally distinct from and possibly only a 

 local race of albiflavella. The incomplete subbasal 

 orange band on forewing, however, suggests a distinct 

 species. 



