A STUDY OF THE GENUS MONOXIA — BLAKE 169 



these two veiy similar although geographically widely separated 

 colonies. The food plant of both is Chenopodium. 



MONOXIA MINUTA. new specie* 



Plate 19, Figure 10 



Small (2.3 to 3 mm.), slender, oblong, prothorax barely twice as 

 broad as long, the sides angulate, disk impressed in the middle and on 

 the sides; elytra finely but distinctly punctate; pubescence moder- 

 ately dense ; color varying from pale yellow with no markings to thickly 

 speckled with black, but even in the pale specimens the under sur- 

 face more or less darkened. Head variable in color, sometimes entirely 

 pale, sometimes thickly speckled; punctation on occiput nearly con- 

 cealed by fine pubescence. Antennae pale in pale specimens, with 

 darkened edges in dark ones. Prothorax scarcely twice as broad 

 as long, with sides angulate and with distinct basal tooth; disk 

 impressed in the middle and on the sides; punctation hidden by dense 

 pale pubescence; usually entirely pale, sometimes with faint mark- 

 ings. Elytra narrowly oblong, somewhat depressed, with a long, 

 shallow intrahumeral sulcus; punctation dense, fine but distinct; 

 pubescence moderately dense; color varying from entirely pale yellow 

 to thickly speckled with black. Body beneath covered \vith fine pubes- 

 cence; metasternum, at least, and often entire under surface dark; 

 legs pale or speckled. Length, 2.3 to 3 mm.; width, 1.2 to 1.4 mm. 



Type, male, and 4 paratypes (3 males, 1 female), U. S. N. M. No. 

 44027, collected by H. K. Morrison. Three paratypes in Museum 

 of Comparative Zoology, Bowditch collection, Cambridge. 



Type locality. — Arizona ("No. Sonora, Mexico"). 



Remarks. — This is one of the smaller species of Monoxia and is 

 distinguished by its slender, oblong shape, its angulate prothorax, 

 distinctly punctate elytra, and long curved aedeagus that has a broad 

 flattened tip, the dorsal opening on which is situated at some dis- 

 tance from the tip. It differs from the sordida group in having a 

 narrower prothorax and in being more distinctly and yet not coarsely 

 punctate. Like M. obesula, its aedeagus is long and flattened at the 

 tip, but the tip is broader. It is a narrower species than obesula, 

 and the sides of the prothorax are more angulate and the disk more 

 depressed. 



There are several forms very closely related to this species. Pos- 

 sibly M. minuta is a representative of another group like that to 

 which consputa, angularis, and sordida belong, which may be still 

 actively evolving. A series of specimens from Salt Lake, Utah, and 

 one from ChaUis, Idaho, are unusually small, a little more coarsely 

 punctate, and although the aedeagus is similar the dorsal opening 

 is situated nearer the tip. Still other series from Flagstaff, Williams, 

 Bright Angel, and Ashfork, Ariz., are slightly larger and more coarsely 



