Strumigenys crementa

Identification
A member of the crassicornis complex in the Strumigenys gundlachi group.

Distribution based on Regional Taxon Lists
Neotropical Region: Costa Rica, Honduras, Panama.

Nomenclature

 *  crementa. Pyramica crementa Bolton, 2000: 182 (w.) COSTA RICA. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 118

I record this as a separate species with some trepidation as its close relationship with Strumigenys brevicornis is obvious. However, none of the many samples of brevicornis examined is as large as Strumigenys crementa, and none has such large eyes nor the same petiolar and gastral pilosity. Perhaps new collections will eventually bridge the apparent gap between the two, but for the present I consider it best to regard them as distinct species.

I currently refer the Panama material mentioned here to crementa. It consists of a single worker (MCZ) that is larger and darker in colour than known specimens from Costa Rica (HL 0.68, HW 0.54, CI 79, ML 0.34, MI 50, SL 0.28, SI 52, PW 0.38, AL 0.74). Many species have a larger, darker form that seems to be a function of altitude distribution, but so little material of crementa is known that this specimen should be re-examined when crementa itself is better understood.

Worker
HOLOTYPE. TL 2.4, HL 0.61, HW 0.46, CI 75, ML 0.28, MI 46, SL 0.24, SI 52, PW 0.32, AL 0.64. Characters of crassicornis-complex. Mandible with 5 – 6 denticles between apicodorsal tooth and submedian tooth, with 1 - 3 minute denticles proximal of the submedian tooth. Eye with 4 ommatidia in the longest row, with 12 – 13 ommatidia in total. Basically crementa appears to be an extra-large version of brevicornis, but with shorter scapes (compare measurements). Morphologically the two are very similar but in crementa the labral lobes are longer and the erect hairs on the first gastral tergite are simple. The backcurved pair of stout hairs located posteriorly on the petiole dorsum are slender, scarcely thicker apically than basally. In brevicornis hairs on the first tergite are stoutly remiform or distinctly flattened and expanded apically; those on the petiole node dorsum are thickly remiform.

PARATYPE. TL 2.3, HL 0.62, HW 0.46, CI 74, ML 0.28, MI 45, SL 0.22, SI 48, PW 0.31, AL 0.62.

Type Material
Holotype worker, Costa Rica: Provo Alajuela, Cordillera de Tilaran, Res. For. de San Ramon, ca 750 m., iii.1990 (P.M. Hammond) (BMNH).

Paratype. 1 worker with same data as holotype.