Pogonomyrmex californicus (Buckley, 1867)

Johnson, Robert A., Overson, Rick P. & Moreau, Corrie S., 2013, A New Species of Seed-harvester Ant, Pogonomyrmex hoelldobleri (Hymenoptera: Formicidae), from the Mohave and Sonoran Deserts of North America, Zootaxa 3646 (3), pp. 201-227 : 225

Key to the workers in the Pogonomyrmex californicus group from central and western North America

( P. anzensis is included, though it may not belong in this species group)

1 Basal tooth strongly offset from basal margin; diastema present between basal and sub-basal teeth, mandible sometimes with eight teeth when a very small tooth occurs in diastema.................................................. snellingi

- Basal tooth not offset, lacking diastema between basal and sub-basal teeth....................................... 2

2 Dorsum of petiolar node, viewed from side, distinctly flattened, and viewed from above, with strong widely spaced wavy, subparallel rugae and usually a distinct, broad, shallow, longitudinal depression; propodeum armed with short to long spines; cephalic interrugal punctures prominent............................................................ comanche

- Dorsum of petiolar node, viewed from side, not flattened, and viewed from above, lacking strong, widely spaced, wavy, subparallel rugae and a broad, shallow longitudinal depression; propodeal armature present or absent; cephalic interrugal punctures absent to prominent........................................................................... 3

3 Mandible with six teeth and circumocular whorls present; venter of postpetiole with a strong, triangular tooth..... anzensis

- Mandible with seven teeth or mandible with six teeth and cephalic rugae extending to vertex in side view, not forming circumocular whorls; venter of postpetiole lacking a strong triangular tooth........................................ 4

4 In side view, eye unusually large, OI usually> 28.5 and malar ratio usually <1.0; circumocular whorls usually present, though sometimes indistinct........................................................................ magnacanthus

- In side view, eye not unusually large, OI <27.5 and malar ratio usually> 1.05; circumocular whorls present or absent.... 5

5 Propodeal spines absent or with a pair of angles, denticles, or short to long spines; cephalic interrugal punctulation rather strong and interrugal punctulation of mesepisternum moderate to strong; rugae on mesepisternum often indistinct; interrugal spaces dull to weakly shining in both areas; circumocular whorls usually present; posterior declivity of propodeum with transverse rugae, not smooth and strongly shining.................................................... maricopa

- Propodeal spines absent; cephalic interrugal punctulation absent to weak and interrugal punctulation of mesepisternum absent to moderately strong; rugae on mesepisternum usually distinct; interrugal spaces moderately to strongly shining in both areas; circumocular whorls present or absent; posterior declivity of propodeum lacking transverse rugae, smooth and strongly shining 6

6 Mandibles with six teeth, a seventh small (subequal) tooth sometimes present between basal and sub-basal teeth; cephalic rugae extending more or less directly to the vertex in side view, not converging posterior to eyes or forming circumocular whorls; gaster concolorous with head and mesosoma................................................ mohavensis

- Mandibles with seven teeth; cephalic rugae forming circumocular whorls or rugae (sometimes faint) converge at or near vertex, but not forming circumocular whorls; gaster black or concolorous with head and mesosoma................... 7

7 Circumocular whorls almost always present, occasional individuals with rugae converging toward vertex; area posterior to eyes always with distinct rugae; interrugal spaces on pronotal sides smooth and shining, rarely weakly granulate; gaster black or concolorous with head and mesosoma.......................................................... californicus

- Circumocular whorls absent, cephalic rugae converging near vertex or area posterior to eye with very faint rugae; interrugal spaces on pronotal sides moderately to strongly granulate, dull to weakly shining; gaster concolorous with head and mesosoma.......................................................................................... hoelldobleri