June, 1909.] Wheeler: North American Formicid^. 79 



V 

 2, Pogonomyrmex (Ephebomyrmex) pima, new species. 



Worker. — Length 3.5-4 mm. 



Head rectangular, a little longer than broad, with straight, subparallel sides and 

 feebly excised posterior border. Eyes somewhat flattened, just in front of the middle 

 of the head. Clypeus short, slightly convex in the middle, with straight, entire an- 

 terior border and without a tooth in front of each antennal fovea. Frontal area dis- 

 tinct. Antennal scapes reaching nearly half way between the eyes and posterior 

 corners of the head ; funicular joints 3-7 as broad as long, remaining joints distinctly 

 longer than broad. Thorax short, robust, broader in frpnt than behind, with rounded 

 humeri ; dorsum in profile broadly rounded. Epinotal spines approximated, erect, 

 compressed, rather blunt, a little longer than broad at their bases, further apart than 

 long, connected by a prominent transverse ridge, separating the base from the declivity 

 of the epinotum. A prominent ridge also runs down the side of the declivity from 

 each spine and forward on each side of the base. Metasterna projecting upward as 

 acute, compressed teeth, shorter and broader than the epinotal spines. Petiole with 

 a narrow, laterally compressed peduncle, which is as long as the node ; the former 

 with a blunt anteroventral tooth, the node in profile conical, with straight, subequal 

 anterior and posterior slopes and rather angular summit ; seen from above the pos- 

 terior slope is subelliptical, i^ times as long as broad. Postpetiole campanulate, as 

 long as broad, in profile evenly rounded abr)ve, with its anteroventral surface convex 

 and protruding. Gaster elliptical, rather small, formed very largely by the first seg- 

 ment. Legs stout, with incrassated femora. 



Mandibles opaque, striated throughout. Head, thorax, petiole and postpetiole 

 opaque. Head, including clypeus and frontal area, covered with coarse, longitudi- 

 nal rugae, which diverge somewhat behind towards the posterior corners of the head 

 and converge on the clypeus towards the middle of its anterior border. Interrugal 

 spaces densely and finely punctate. Thorax coarsely reticulate-rugose, the rugas 

 being vermiculate and sublongitudinal on the pleurae and mesonotal region. Neck 

 finely and transversely rugulose. Epinotal declivity with a single pair of coarse ridges 

 or rugae between the pair descending from the bases of the spines. Petiolar node and 

 postpetiole coarsely shagreened, with a few shallow and scattered punctures. Legs 

 and gaster somewhat shining, the latter more finely shagreened than the petiole and 

 postpetiole, with rather coarse, scattered, piligerous punctures. Antennal scapes 

 opaque. 



Hairs blackish, short, erect and stubby on the body, scarcely more oblique on the 

 legs and antennal scapes and not elongated to form ammochjetae on the gula. 



Rich ferruginous red, posterior portions of thorax somewhat darker ; antenna 

 and legs yellow ; mandibular teeth black. 



Described from a dozen specimens taken by myself at Tucson, 

 Arizona, and a single specimen taken at Phoenix in the same state. 



This species is closely related to F. {E.) mege/iForel from Brazil 

 and -P. {£.) imberbiculiis Wheeler from Texas, but differs from both 

 in lacking the teeth on the clypeus in front of the antennal fovese, and 

 in the sculpture of the head, petiole and postpetiole. In both the 

 species mentioned the head is coarsely reticulate-rugose and in ticegeli 



