46 U.S. NATIONAL MUSEUM BULLETIN 280 



Key to the Species of the Albidella Group 



Forewing appearing lighter posterior to Aj fold; posterior cusp of spicate process a 

 small triangular tooth about one-eighth length of anterior cusp (fig. 123) 



albidella 



Forewing not appearing lighter posterior to Ai fold; posterior cusp of spicate 

 process a sharp thorn about one-fourth length of anterior cusp (fig. 124) . artella 



Arivaca albidella (Hulst), new combination 



Figures 17, 88, 123, 160 



Peoria albidella Hulst, 1900, pp. 175, 439. — Barnes and McDunnough, 1917, 

 p. 149.— McDunnough, 1939, p. 36. 



Diagnosis. — Distinguishing features are given in the above key. 



Description. — Forewings Hght tan to grayish brown, appearing 

 Ughter posterior to Ai fold. 



Male genitaha with posterior cusp of spicate process poorly de- 

 veloped, usually rounded, sometimes sharp pointed, usually no more 

 than one-tenth length of anterior process. 



Type. — In the U.S. National Museum. 



Type data. — Lectotype male, hereby designated, Death Valley, 

 "April 91 K."; USNM 4809; genitalia shde No. 571, J. Shaffer, 

 Nov. 23, 1965. In the original description Hulst notes: "Death Valley, 

 Cal. ; taken by Mr. Koebele, in April. The type number of the 

 National Museum is 4709." 



Specimens EXAMINED. — 7 d^, 1 9. 



Distribution (Map 9). — Southwestern United States. 



UNITED STATES: New Mexico: Dona Ana Co., Mesquite, near MesiUa 

 Park,2 2 cT, July 12, 1917 [CU]. 



Texas: Reeves Co., Pecos, 4 cf , 1 ?, May 18, 1950 (E. C. Johnston) [CNC]; 

 1 cf , June 2, 1950. 



Arivaca artella, new species 



Figures 18, 89, 124, 161 



Diagnosis. — Distinguishing features are given in the above key. 



Description. — Male genitalia with posterior cusp of spicate process 

 well developed as a sharp-pointed thorn about one-fourth as long as 

 anterior cusp. Apical process of gnathos strongly projected, somewhat 

 T-shaped in lateral view. 



Type. — In the Cornell University collection. 



Type data. — Holotype male, Mesquite near MesiHa Park, N. Mex., 

 July 12, 1917; Cornell University lot No. 542, sublot No. 46; lot No. 

 551, sublot No. 916; CU Type No. 4406; genitalia slide No. 366, J. 

 Shaffer, Feb. 12, 1965. 



2 Spelled Mesille Park on specimen labels. 



