Crematogaster pygmaea

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil.

Biology
In this and other species belonging to the subgenus Orthocrema, a third caste exists in addition to winged queens and workers; it is intermediate in size, weight and morphology. These individuals are numerically few in the colonies, and lay many unfertilized eggs that are mostly eaten by larvae. Histology confirmed the lack of a spermatheca. Using scanning electron microscopy and ovarian dissections, Peeters et al. (2013) showed that this third caste is a patchwork of queen-like and worker-like traits. It is a soldier caste with a specialized trophic function. They are produced seasonally in C. pygmaea.

Nomenclature

 *  pygmaea. Crematogaster pygmaea Forel, 1904c: 37 (w.) BRAZIL. Combination in C. (Orthocrema): Emery, 1922e: 135. Subspecies of brevispinosa: Forel, 1909a: 259. Revived status as species: Forel, 1912f: 235; Emery, 1922e: 135. Junior synonym of abstinens: Longino, 2003a: 30. Revived from synonymy: Quinet, Hamidi, et al. 2009: 45.

Additional References

 * [[Media:Peeters etal. ASD2013 Orthocrema.pdf|PEETERS, C., LIN, C.-C., QUINET, Y., MARTINS SEGUNDO, G. & BILLEN, J. 2013: Evolution of a soldier caste specialized to lay unfertilized eggs in Crematogaster ants (subgenus Orthocrema). Arthropod Structure & Development 42: 257-264. PDF]]