1944] Genus Pseudomyrma 97 
The new species is readily separated from the more closely 
related species by the shape of the petiole in profile; weberi is 
the only species that has the posterior face of the peduncle con- 
cave; the antero-ventral tooth is very small and bears a single 
long hair. 
Type locality: Esquintla, Guatemala. 
Cotype 26815, Museum Comp. Zook, No. 88, Haskins Col- 
lection. 
Pseudomyrma wessoni sp. nov. 
Worker. 
Length 3.5-4 mm. Head 1*4 longer than broad with weakly 
convex sides and straight posterior border. The eyes occupy 
more than 2/3 the sides of the head. Mandibles pale yellow, 
longitudinally striated and opaque. Clypeal lobe with convex 
anterior border. Antennal scapes reach the middle of the eyes. 
Antennae pale yellow, head darker yellow, very heavily punctate 
and opaque. Prothorax much longer than broad; margined and 
convex above. Mesothoracic disc convex. Epinotal base longer 
than broad, broadest at the level of the stigmata. Petiole from 
above triangular, with convex posterior edge, sharply margined. 
Postpetiole broader than long. Thorax in profile with very deep 
and broad mesepinotal depression; epinotal base much higher 
than the prothorax, convex, with a sharp angle at the declivity. 
Petiole in profile subtriangular, differing from all other species 
of the subgenus Apedunculata by its vertical posterior face. 
P. allidora has a similar petiole but the antero ventral tooth is 
blunt in the latter species, not sharp as in wessoni. 
Color almost uniformly reddish yellow, with the tibiae lighter. 
Pilosity short and sparse ; pubescence relatively abundant, fine, 
silky and adpressed. Pedicel and gaster shiny, the rest opaque. 
Type locality: Lima, Peru. 
The new species is related to P. subtillissima, sericea, allidora , 
acanthobia and colei. It differs from each of these by the shape 
of the pedicel in profile, which is very short, with a vertical 
posterior face and a sharply recurved antero ventral tooth. 
Female. 
The female is of nearly the same size as the worker and with 
the same characters, except for the cast differences. There is 
a tendency to darker coloration; more brownish red, with an 
indication of bicoloration (the prothorax lighter brown than the 
rest of the thorax) . 
