Crematogaster biroi

Nests in soil.

Distribution based on Regional Taxon Lists
Oriental Region: India, Sri Lanka , Taiwan. Palaearctic Region: China.

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.

Nomenclature

 *  biroi. Crematogaster biroi Mayr, 1897: 428 (w.) SRI LANKA. Bingham, 1903: 138 (q.); Imai, et al. 1984: 6 (k.). Combination in C. (Orthocrema): Emery, 1922e: 131. Senior synomym of aitkenii, smythiesii, urvijae: Hosoishi & Ogata, 2016: 577.
 * aitkenii. Crematogaster biroi var. aitkenii Forel, 1902c: 203 (w.) INDIA. Combination in C. (Orthocrema): Emery, 1922e: 132. Raised to species: Wu & Wang, 1992: 1319. Junior synonym of biroi: Hosoishi & Ogata, 2016: 577.
 * smythiesii. Crematogaster biroi var. smythiesii Forel, 1902c: 203 (w.q.) INDIA. Combination in C. (Orthocrema): Emery, 1922e: 132. Junior synonym of biroi: Hosoishi & Ogata, 2016: 577.
 * urvijae. Crematogaster (Crematogaster) urvijae Bharti, 2003c: 85, figs. 1-9 (w.q.) INDIA. Junior synonym of biroi: Hosoishi & Ogata, 2016: 577.