Crematogaster (Physocrema) vacca Forel

Hosoishi, Shingo & Ogata, Kazuo, 2009, A taxonomic revision of the Asian endemic subgenus Physocrema of the genus Crematogaster (Hymenoptera: Formicidae), Zootaxa 2062, pp. 15-36 : 30

Crematogaster (Physocrema) vacca Forel , stat. nov.

( Fig. 19 , 31 )

Crematogaster deformis vacca Forel, 1911: 384 . LECTOTYPE worker (by present designation) from MALAYSIA: Berhentian Tingi, Nigri Sembilan, Malacca (R. Martin) (MHNG) [examined]. Combination in C. ( Physocrema ) by Emery, 1922: 140.

Crematogaster (Physocrema) stethogompha Wheeler, W. M., 1919: 75 . LECTOTYPE worker (by present designation) and paralectotype workers from MALAYSIA: Kuching, Borneo, No. 8948 (H. Smith) (MCZC). [examined]. Syn. nov.

Crematogaster (Physocrema) stethogompha var. detritinodis Wheeler, W. M., 1919: 77 . Syntype worker from MALAYSIA: Kuching, Borneo, No. 20820 (H. Smith) (MCZC). [examined]. Syn. nov.

Measurements and indices. HW 1.09–1.62; HL 1.03–1.46; CI 106–111; SL 0.91–1.14; SI 70–83; EL 0.20–0.26; PW 0.64–0.84; WL 1.32–1.76; PSL 0.16–0.18; PtL 0.41–0.54; PtW 0.37–0.42; PtH 0.23–0.30; PpL 0.23–0.30; PpW 0.30–0.42; PtHI 56–57; PtWI 78–90; PpWI 129–140; WI 81–100 (Three workers measured).

Description of worker. Workers with pronounced size polymorphism.

Scape not reaching posterior corner of head in large workers.

In lateral view, pronotum and mesonotum forming a single convexity; propodeum distinctly raised relative to promesonotum. Anterior margin of pronotal collar slightly concave in dorsal view. Metanotal groove convex posteriorly in dorsal view, deep and situated posteriorly to the posterior ridge of pronotum in lateral view; thorax not strongly constricted in middle in dorsal view. In dorsal view, many longitudinal rugulae connecting between mesonotum and propodeum; but the boundary distinct. Propodeal spiracle situated away from the metapleural gland orifice, the distance between them much greater than the propodeal spiracle diameter. Propodeal spines present.

Postpetiole slightly bilobed behind without longitudinal median sulcus.

Clypeus sculptured with longitudinal rugulae. Reticulate rugulae on dorsal face of head, pronotum, mesonotum and propodeum.

Standing pilosity sparse on dorsal face of head and mesosoma. Dorsal face of head with appressed setae. Fourth abdominal tergite with a few erect setae and abundant appressed setae.

Body color dark brown to black.

Distribution. This species is known from Malay Peninsula and Borneo ( Fig. 31 ).

Remarks. The name on the labels of the type specimen,“ Crematogaster stethogompha laevinodis ” does not correspond to the name “ Crematogaster stethogompha detritinodis ” used in Wheeler’s description. He presumably changed the name between the time the labels were prepared and the manuscript submitted.

This species is easily distinguished from difformis and its subspecies by the well developed propodeal spines. We treated it as a distinct species.

Specimens examined. MALAYSIA: 3 workers, Pasoh Forest Research Center, Negeri Sembilan, xi. 1994 (fog sample, M. Brendell, K. Jackson and S. Lewis); 1 worker, Old Tower R., Lambir N.P., Miri, Sarawak, 20. i. 1993 (Sk. Yamane); 1 worker, Old Tower R., Lambir N.P., Miri, Sarawak, 22. i. 1993 (Sk. Yamane).

Figures

FIGURES 18 − 20. Physocrema species in lateral view. Scale bars are all 0.5 mm. 18 — C. (P.) tanakai, holotype [Lambir N. P., Miri, Sarawak, Borneo]; 19 — C. (P.) vacca, [Old Tower R., Lambir N. P., Miri, Sarawak, Borneo]; 20 — C. (P.) yamanei, holotype [Parapat (900 m alt), Danau Toba, N. Sumatra].

FIGURES 27 – 32. Distribution of Physocrema species in Southeast Asia. 27 — C. (P.) onusta; 28 — C. (P.) physothorax; 29 — C. (P.) sewardi; 30 — C. (P.) tanakai; 31 — C. (P.) vacca; 32 — C. (P.) yamanei.