1903] FERXALD:— TWO NEW SPECIES OF SPJIEX 20I 



TWO NEW SPECIES OF SPHEX. 



BY H. T. FERNALD, PH. D., AMHERST, MASS. 



Sphex nudus, sp. nov. 



Head. Black, covered with long yellowish white hairs. Clvpeus and frons covered 

 with pale straw-colored pubescence to, or slightly above the insertion of the antennae, except 

 at middle of anterior edge of clypeus where it hardly reaches the edge. A noticeable furrow 

 passes forward (downward) a short distance, from the median ocellus. Surface of frons with 

 rather coarse, scattered punctures. Mandibles black at base and from the bases of the two 

 teeth to their tips; elsewhere ferruginous. Antennae black, third segment longest; scape 

 with short, pale straw-colored hairs. 



Thorax. Collar with faint scattered punctures and a few pale hairs ; with a trace of 

 yellowish white pubescence on its dorsal edge. Prothoracic lobe black, posterior portion 

 somewhat pubescent, fringed behind with pale hairs. Just behind the lobe is a vertical band 

 of pale yellowish pubescence more or less pronounced. Mesonotum somewhat punctured, 

 with short grayish white hairs, and a faint median longitudinal groove on its anterior third. 

 Scutellum rather more sparsely and finely punctured, with a slight median depression, and 

 covered with short, grayish white hairs. Postscutellum pale yellowish white pubescent as 

 far laterally as where the groove of the median segment leading to the stigma originates. 

 This pubescence is frequently in part or entirely absent. Median segment finely, trans- 

 versely aciculate, covered with yellowish white hairs longer than those of the mesonotum 

 and scutellum. Above the petiole ^re two yellowish white pubescent areas partly confluent 

 ■on the median line. Petiole short, straight, black, with yellowish white hairs. 



Abdomen. Above, smooth, gray sericeous, very faintly punctured, the last two seg- 

 ments bearing grayish and brownish hairs directed backwards. Terminal segment rounded, 

 somewhat compressed on its posterior half at the sides, forming a slight median ridge (Fig. 

 •6). Beneath, glistening, somewhat sericeous, with a few scattered grayish hairs, which on 

 the fifth, sixth, and seventh ventral plates become tufts, one on each side, on each of the 

 segments named. Eighth segment somewhat emarginate on its hinder border. Ninth 

 (terminal) segment rounded at the sides, with a spine on the posterior edge (Fig. 4) giving 

 this plate the same form as that found in Sphex Jlavipes. 



Wings. Nearly hyaline, the front pair very slightly fuscous. Tegulae black, margins 

 <lull ferruginous ; traces of a yellowish pubescence present. 



Legs. Tibiae and tarsi yellow ferruginous except last tarsal segment and claws which 

 are much darker or almost black. Spines of legs yellow ferruginous. Coxae, trochanters, 

 and the greater portion of femora black, the tips of the latter yellow ferruginous. Coxae 

 sparsely punctured, sericeous, with a few scattered hairs. 



Length, 18-22 mm. 



Described from six male specimens : one taken in Tenn., now in the collection 

 of the U. S. national museum ; the others captured Aug. 23, 1902, at Indian Head, 

 Md,, by Mr. J. C. Bridwell on flowers of Monarda punctata L., and now in the col- 

 lections of the American entomological society at Philadelphia, Massachusetts 



