58 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



usual proportions. Prothorax a little wider than long and about 

 half as long as elytra, the anterior margin somewhat thickened and 

 projecting over the head; sides 3-toothed, surface covered by dense, 

 round punctures becoming coarser toward base and nearly concealed 

 by the broad, curved, brown and white scales ; depressed along basal 

 margin, especially over the scutellum. Elytra with a transverse de- 

 pression below basal callosities ; densely covered by the broad, curved, 

 brown and yellow scales, scales producing an irregularly mottled ap- 

 pearance and nearly concealing the striate punctation below; punc- 

 tures well spaced and becoming finer toward apex with a tendency to 

 ridging in basal part. Body beneath lightly covered by finer white 

 scales, punctation on first abdominal segment not coarse or dense. 

 Anterior tibiae with the usual toothing. Length 5.3 to 6 mm. ; width 

 2.5 to 2.8 mm. 



Type and "paratypes. — Type and one paratype in Miguel Lillo Insti- 

 tute, Tucuman, Argentina, collected January 3, 1949, by Kuschel ; one 

 paratype, U.S.N.M. No. 59365 ; one paratype in Museum of Compara- 

 tive Zoology. 



Type locality. — Mamore ( ? river) , Trinidad, Bolivia. 



Remarks. — This is one of the reddish-brown species, with a thick- 

 ened anterior margin on the prothorax concealing the head. Only 

 one other South American species has these two characteristics to- 

 gether, M. holivianus, which is a stouter beetle having a quite different 

 scale pattern. 



MYOCHROUS PORTORICENSIS Blake 



Plate 7, Figure 1 

 Myochrous portoricensis Blake, Proc. Ent. Soc. Washington, vol. 49, p. 25, 1947. 



From 5 to 6 mm. in length, oblong, shining dark brown to piceous 

 black, beneath the dense pale scales. Prothorax covered with round, 

 deep, but not at all confluent or ridged punctures; elytra with the 

 striate punctures not so closely placed as in cubensis Blake. 



Head covered by scales down to antennal sockets; a faintly de- 

 pressed median line down front ending in a broad shallow depres- 

 sion; punctation deep, coarse, but not ridged, and lower front less 

 densely punctate than in cubensis; the usual occipital ridges on either 

 side. Prothorax a little wider than long with three well-developed 

 lateral teeth and a slight depression along basal margin most marked 

 over the scutellum; punctures not very coarse, round, deep, and so 

 spaced as not to be confluent or ridged. Elytra with striate punc- 

 tures well-spaced, not so close as in cubensis., coarse in basal part, be- 

 coming much finer toward apex. Body beneath with finer, sparser 

 scales, punctures on first abdominal joint fine, not very dense. Hind 

 femora inconspicuously toothed, anterior tibiae with the usual tooth. 

 Length 5.2 to G mm. ; width 2.4 to 3 mm. 



