32 PROCEEDINGS OF THE NATIONAL MUSEUM vol.82 



12. DISONYCHA TENUICORNIS Horn 



Plate 3, Figure 12 



Disonycha tenuicornis Horn, Trans. Amer. Ent. Soc, vol. 16, p. 208, 188& 

 (southern Arizona; type in Horn collection, Acad. Nat. Sci., Philadelphia). 



Description. — Broadly oblong oval, moderately shining, pale with 

 two anterior dark pronotal spots, and very narrow dark median 

 elytral vitta and narrowly darkened sutural edges, the submarginal 

 vitta usually being only faintly indicated; antennae unusually long 

 and slender, extending fully half the length of the elytra in the 

 female (longer in the male). Head with interocular space more than 

 half width of head; interantennal area broad and flat, frontal tu- 

 bercles scarcely marked, occiput and front smooth and shining, only 

 a few scattered punctures on either side about fovea near eye; head 

 entirely pale. Antennae dark with paler basal joints; long and 

 slender, extending fully half length of elytra, third joint a little 

 shorter than fourth and fifth, which are subequal, the fourth slightly 

 longer, sixth and seventh nearly as long. Prothorax not twice as 

 broad as long, nearly rectangular with sides only slightly arcuate, 

 somewhat convex; shining, almost impunctate; pale with two an- 

 terior dark spots. Scutellum dark brown. Elytra somewhat convex, 

 oblong, with humeri not prominent and with little trace of an intra- 

 humeral sulcus ; moderately shining, under high magnification finely 

 alutaceous and finely punctate; pale with unusually narrow median 

 vitta, sutural vitta usually consisting of scarcely more than darkened 

 sutural edges, submarginal vitta poorly defined, more distinct and 

 wider at apex and uniting with sutural vitta. Body beneath densely 

 covered with fine pubescence, entirely pale, legs pale with a darkened 

 streak on outside of femora, tarsi brown. Claws with basal tooth 

 much longer than in other species of the genus. Length, 6 to 7.6 mm ; 

 width, 3 to 4.5 mm. 



Type locality. — Southern Arizona; type collected by H. K. Mor- 

 rison. 



Distrihutio7i. — New Mexico (Alamogordo, Organ Mountains) ; 

 Arizona (Chiricahua Mountains, Cochise County). 



Food plant. — Unknown. 



Reinarhs. — Disonycha tenuicornis, a species so far found only in 

 New Mexico and Arizona, is unusual in having long and very slender 

 antennae. It is broadly oblong with a broad head, and the elytra 

 have very narrow vittae. In the specimens examined, the male is 

 considerably smaller than the female. I have seen only a few 

 specimens, and since the species is apparently rare, these deserve 

 particular mention. I have examined three specimens in Horn's 

 collection, 2 from Alamogordo, N. Mex., and 1 from Arizona; 1 in 



