Crematogaster quadriformis Roger

Wild, A. L., 2007, A catalogue of the ants of Paraguay (Hymenoptera: Formicidae)., Zootaxa 1622, pp. 1-55 : 52

Crematogaster quadriformis Roger 1863a.

Crematogaster quadriformis Roger 1863a: 207.

Crematogaster quadriformis var gracilior Forel 1901c. NEW SYNONYMY. [w syntypes examined, MHNG; São Paulo, Brazil]

Crematogaster quadriformis subsp. vezenyii Forel 1907b: 25. NEW SYNONYMY.

Crematogaster quadriformis r gracilior Forel . Forel 1912c: 218.

Crematogaster (Orthocrema) quadriformis Roger . Santschi 1918: 182.

Crematogaster (Orthocrema) quadriformis subsp. gracilior Forel . Emery 1924a: 135.

Crematogaster (Orthocrema) quadriformis subsp. vezenyii Forel . Emery 1924a: 135.

Crematogaster (Orthocrema) quadriformis gracilior Forel . Kempf 1972: 88.

Crematogaster (Orthocrema) quadriformis vezeneyii Forel . Kempf 1972: 89.

Crematogaster quadriformis is the most frequently recorded ground-nesting Crematogaster in Paraguay. This species can be diagnosed by the following combination of character states: propodeum in profile only slightly or not at all depressed below level of mesonotum; propodeal spines elongate but shorter than length of petiole; antennal scapes equal or greater in length than head length, in repose well exceeding the posterior margins of the head in full-face view; head sculpture densely punctate/striate except for a smooth frontal strip;>20 subdecumbent to suberect setae on the first gastric tergite. Crematogaster quadriformis shows considerable variation even within nest series in overall size, pilosity, eye size, and extent of punctation/striation on the head.

Jack Longino examined some recent Paraguayan collections and confirmed the identity of this species as C. quadriformis . I have subsequently viewed Forel’s types of C. quadriformis gracilior from São Paulo and found them to fall well within the range of variation I have observed in Paraguay, so I synonymize C. gracilior here.

I was not able to view Forel’s types of C. quadriformis vezenyii , described from material collected in Asunción. Forel’s description notes small size, a more shiny head, and lack of a well-developed tooth in the propodeal suture. These character states are common in the C. quadriformis material I have examined towards the small end of the size distribution of nest series, so I find it likely that C. quadriformis vezenyii is a collection of a young nest or small workers of C. quadriformis .