1969] 
Brown and Kempf — A canthognathus 
97 
V-shaped) ; posterior lobes very narrowly rounded. Mandibles 
slender and more than ^4 the head length (see Table I), with low 
welts or convexities developed on their inner margins beyond mid- 
length, but no preapical denticles. Compound eyes normally broad- 
elliptical, only weakly convex, with about 34-45 facets, greatest 
diameter 0.11-0.13 mm. One (Trinidad) specimen has the left 
eye abnormally small (diameter 0.08 mm, only about 9 facets), 
whereas the opposite eye is nearly normal in size and facet number. 
The petiole is quite slender, especially as viewed from the side, and 
its node is a bit lower than in A. rudis; petiolar node widths of the 
available sample (n = 5) are 0.16-0.19 mm, modal at O.17; while 
for A. rudis the width is 0.17-0.20 mm, modal at 0.18. 
The fossae of the sculpture are crowded on the anterior part of the 
cephalic dorsum, but are mostly well-separated on the posterior half 
of the head, with smooth or nearly smooth, shining interspaces. The 
fossae themselves have broad, shining bottoms. In the Trinidad 
worker, the posterior fossae are more often contiguous, and longitu- 
dinal rugulae begin to appear between some of them, making transi- 
tion toward the doubtfully distinct A. lentus. Sculpture of the 
truncus variable; rugulose-punctulate, with interspersed small fossae; 
sides of mesonotum usually smooth and shining, with scattered in- 
distinct fossae, as is sometimes also the anterior part of the propodeal 
dorsum. Reticulo-punctulate sculpture of petiolar node confined to 
lowest parts of the sides (usually occupies most of side of node in 
A. rudis). Pilosity abundant on head and promesonotum, but not 
as abundant as in A. rudis. Color light to medium reddish-ferru- 
ginous, appendages lighter and more yellowish, gaster sometimes 
feebly infuscated. 
Queen (dealate) from Belem, Brasil. Greatest diameter of com- 
pound eye 0.19 mm; petiolar and postpetiolar nodes relatively larger 
than in worker from same nest (petiolar node 0.20 mm wide). Pro- 
podeal teeth stout, but still long and acute. Mesonotum with 
crowded distinct fossae, contiguous and nearly so; interspaces and 
fossae smooth or nearly smooth, shining; scutum and scutellum with 
median longitudinal carinula. Mesopleura smooth and shining, sides 
of pronotum rugose-fossulate, sides and dorsum of propodeum in 
part finely rugulose-punctulate. Otherwise differing from the worker 
by the usual caste characters. 
Male unknown. 
