1966] 
Gotwald and Brown — Simopelta 
273 
along, it seemed likely that the worker’s mandibles or under-mouth- 
parts rested in the median sulcus of the queen’s postpetiolar tergum. 
The workers ran rapidly, holding their antennae in much the same 
way as Dorylinae do, and quickly formed files along obvious odor 
trails newly laid on a blank paper surface. Altogther, the impression 
of the colony behavior received was that of an army ant. The slender 
bodies of the ants reminded one of mass-foraging Leptogenys species, 
such as those of the diminuta complex of the Indo-Australian area. 
S. oculata proved able to sting, at least through the thin skin on 
the back of human fingers. The sting felt about like a mosquito bite, 
and lasted similarly. 
SunoPelta manni 
Simopelta manni Wheeler, 1935: 17, fig. 4, worker. Type locality: Mera. 
Ecuador. 
This species has acutely 3-toothed mandibles and no clypeal spine. 
Eyes very convex, but smaller than those of oculata. “Mesosternal” 
tooth present. Pronotum and much of head smooth and shining. 
Petiolar node a little broader than long. Color black. Known only 
from type material. 
1 Simopelta bicolor 
Simopelta bicolor Borgmeier, 1950: 377, fig. 13-20, worker. Type locality: 
Santa Teresa, Espirito Santo, Brazil. 
Mandibles with 5-6 irregular teeth basad of the apical pair. No 
clypeal spine or “mesosternal” tooth. Petiolar node much broader 
than long. Head and alitrunk densely punctulate. Bright ferruginous 
red ; petiole and gaster yellow. Known only from type material. 
Simopelta laticeps new species (Figures 15, 16) 
Holotype worker: TL 4.9, HL 1.03, HW 0.93, WL 1.65, great- 
est diameter of eye 0.05, scape L 0.91 mm. Cl 90. 
Immediately separable from the other known species of the genus 
by means of its wide, convex-sided head with notably concave oc- 
cipital margin. The median clypeal lobe bears a slender subspatulate 
tooth, and the mandibular armament consists of 4 strong, acute teeth. 
General form of body and appendages shown well in Figs. 15 and 
16. Petiolar node broader than long. Head finely and densely striato- 
punctulate in a longitudinal direction ; dorsum of pronotum and 
mesonotum with similar sculpture, arched concentrically; sides of 
alitrunk mostly longitudinally striate; dorsum of propodeum and 
