1962 ] 
Brown — Strumigenys 
263 
Smaller (HL < 0.80 mm) ; mandibles narrower, not or only 
indistinctly arcuate 37* 
37. Basigastric costulae absent or extremely reduced, never much 
longer than the space separating one from the next ; anterodorsal 
face of petiolar node convex in both directions (Amazon Basin 
to Bolivia) prospiciens Emery 
Basigastric costulae fine but numerous, extending at least 1/8 the 
length of gastric tergite I; anterodorsal face of petiolar node 
obliquely depressed, nearly or quite plane (tropical S. and C. 
America, St. Vincent I.) smithii Forel 
38. Mandible with a single small preapical tooth; no additional pre- 
apical teeth or denticles on inner border 39. 
Mandible with 2 or more preapical teeth and/or denticles ... 40. 
39. Larger form with long mandibles (ML > 0.42 mm; MI 68 or 
more; see discussion, p. 247) (Bolivia) producta Brown 
Smaller form with shorter mandibles (ML < 0.42 mm; MI < 
68) (Tennessee and Arizona to n. Argentina and Bolivia, W. 
Indies) louisianae Roger 
40. Mandible with at most 2 preapical teeth and/or denticles (Fig. 
15 ) 41 - 
Mandible with 3 or more preapical teeth and/or denticles (Figs. 
10, 11) 44. 
41. Mandible with 1 preapical tooth and a single additional minute 
denticle near the apical third of the mandibular length (Fig. 15); 
gastric dorsum predominantly reticulate-striate, opaque, with stiff 
remiform erect hairs (Guatemala) mixta Brown 
Mandible with two well-developed preapical teeth 42. 
42. Smaller species, HL < 0.75 mm; erect hairs of gaster stiff, slight- 
ly clavate or remiform (known from female only; possibly an 
inquiline in nest of S. laevipleura; Colombia) 
xenognatha Kempf 
Larger forms, HL > 0.75 mm ; erect hairs of gaster few, strag- 
gling fiagelliform 43. 
43. Dorsum of basal gastric segment with longitudinal costulae only 
at base, otherwise smooth and shining; short, thickened reclinate 
ground hairs of gastric dorsum abundant and conspicuous (Ama- 
zon Basin) tococae Wheeler 
Dorsum of basal gastric segment longitudinally striolate for its 
full length; reclinate ground hairs of gastric dorsum obsolete or 
apparently so (Panama) fairchildi Brown 
44. Postpetiolar node smooth and shining when clean ; mandible with 
2 preapical teeth and a denticle (Colombia) .... laevipleura Kempf 
