1962] 
Brown — Strumigenys 
261 
the proximal preapical tooth (Fig, 9) 23. 
Inner mandibular border without a lamellar extension, or, if a 
lamella of sorts is present, its form is not as above (Fig. 14) .. 24. 
23. Lamelliform margin of inner mandibular border ending near mid- 
length of mandible (Fig. 9) ; propodeal teeth very small; gastric 
dorsum predominantly smooth and shining, with vestiture of 
abundant fine, short reclinate hairs (se. Brazil) .. cultriger Mayr 
Lamelliform margin of inner mandibular border ending near 
apical quarter of mandible; propodeal teeth large; first gastric 
tergite predominantly reticulate-striate, opaque, with about 20 
apically-broadened, short erect hairs (Panama) 
deltisquama Brown 
24. Large forms (head width > 0.85 mm) with massive head and 
short, heavy mandibles (MI 50 or less) 25. 
Smaller forms with narrower heads (head width under 0.85 mm) 
and longer, more slender mandibles (MI > 50) 26. 
25. First gastric tergite finely longitudinally striolate for most or all 
of its length; head about as broad as, or broader than, long 
(Amazon Basin) mandibularis Fr. Smith 
Gastric dorsum smooth and shining, with only a narrow basal 
band of reduced costulae; head slightly longer than broad 
(Guiana to Costa Rica) godmani Forel 
26. Gastric dorsum predominantly finely longitudinally striolate, 
sericeous-opaque, with very abundant, fine, erect flagelliform 
pilosity; proximal preapical mandibular tooth small (only about 
half the length of the distal preapical) and situated toward the 
mandibular midlength (Fig, 14; Trinidad to Bolivia and Ecua- 
dor) trinidadensis Wheeler 
Gastric dorsum with either sculpture or pilosity or both different 
from the above ; proximal preapical tooth of mandible more than 
half as long as distal preapical tooth and situated well beyond the 
mandibular midlength 27. 
27. Mandibles very nearly as long as, to distinctly longer than, the 
head proper (MI > 90) 28. 
Mandibles relatively shorter (MI < 75) 32. 
28. Mandibles slightly > 1.00 mm long; distal preapical tooth closer 
to proximal than to apical fork (British Guiana) 
dolichognatha Weber 
Mandibles < 1.00 mm long; distal preapical tooth closer to 
apical fork than to proximal preapical tooth 29. 
29. Mandibles > 0.80 mm long; longitudinal costulation of post- 
petiolar disc absent or incomplete 30. 
