28 
Psyche 
[Vol. 92 
unknown mines in the Dominican Republic, but a large minority 
originated from the following localities, including almost all from 
which I have seen ants of any kind: Carlos Diaz, near Tamboril; 
Cotui; La Bucara; La Cumbre; La Toca; Las Bocas del Licey; Lla- 
roa (Yaroa); Los Cacaos; Marias; Palo Quemado; Bayaguana. The 
specimens share the key characters of the holotype nest series. They 
are quite variable in size (Head Width 0.42-1.06 mm overall), but, 
as documented in Fig. 8, relatively little variation occurs within 
single amber pieces. Moreover, the size variation in one especially 
populous piece I have examined appears to be unimodal with little 
or no skewing. Hence A. azteca must be regarded, at least tenta- 
tively, as a monomorphic species. 
Paratype males. A total of 17 individuals in 8 pieces (3 with 
associated workers). The essential characteristics, placing the spe- 
cies still more firmly within the alfari group and in particular close 
to fiebrigi, are illustrated in Fig. 6. The alitrunk length of the male 
depicted, from the holotype nest series, is 1.04 mm. The Head Width 
(including eyes) of another male measured from Palo Quemado is 
0.72 mm. 
Paratype queens. The elongate head shape of 2 alate queens 
found in separate amber pieces (Dominican Republic, no further 
locality) might seem to associate them logically with A. eumeces, the 
second, rarer Azteca species occurring in the Dominican amber. 
Nevertheless, at least some of the contemporary alfari group species, 
in particular coeruleipennis, fasciata, and fiebrigi, have workers 
with ordinary head shapes and queens with elongated heads. 
Moreover, the Dominican amber queens closely resemble those of 
fiebrigi. 
General remarks. Azteca alpha is by far the most abundant ant 
species and hence probably the most abundant insect species in the 
Dominican amber. It occurs in 29% (171 of 592) of the ant-bearing 
amber pieces 1 have studied closely to date. Since I passed a large 
percentage of the pieces back to dealers prior to the revisionary 
work because they contained A. alpha and thus were considered of 
less interest, the actual representation of the species was much 
higher, very likely 50% or more. 
In addition, A. alpha workers have been found in the same pieces 
as many of the other Dominican amber genera: Pseudomyrmex, 
Crematogaster ( Orthocrema ), Oligomyrmex, Pheidole, Monads, 
Hypoclinea, and Camponotus. This circumstance, plus the occur- 
