Tetramorium ranarum Forel

Bolton, B., 1979, The ant tribe Tetramoriini (Hymenoptera: Formicidae). The genus Tetramorium Mayr in the Malagasy region and in the New World., Bulletin of the British Museum (Natural History) Entomology 38, pp. 129-181 : 151

Tetramorium ranarum Forel

(Fig. 25)

Tetramorium (Xiphomyrmex) ranarum Forel, 1895 b: 486 . Syntype workers, Madagascar: central Madagascar {Sikora) (MHN, Geneva) [examined].

Worker. TL 3.0 - 3.3, HL 0.72 - 0.82, HW 0.68 - 0.76, CI 94 - 97, SL 0.48 - 0.54, SI 67 - 71, PW 0.48 - 0.55 ' AL 0.80 - 0.88 (8 measured).

Mandibles strongly longitudinally striate, anterior clypeal margin with a median notch or impression. Eyes relatively small, maximum diameter c. 0.13 - 0.14, about 0.17 - 0.19 x HW. Frontal carinae strong and surmounted by a raised narrow rim or crest, occipitally becoming weaker and merging into the other cephalic sculpture. Antennal scrobes shallow but broad, the scrobal area with some rugulose sculpture. Propodeal spines elongate and strong, tending to be upcurved along their length. Metapleural lobes broadly triangular and acute. Petiole node in profile blocky, about as long dorsally as the tergal portion is high. In dorsal view the petiole node about as broad as long, in some specimens slightly broader than long and vice versa in others. Postpetiole evenly convex in profile, much broader than petiole in dorsal view. Head predominantly bluntly longitudinally rugulose with some cross-meshes and with a reticulum occipitally, the dorsal surfaces of the blunt rugulae with a beaded appearance due to the presence of aligned punctulae. Spaces between rugulae weakly punctulate. Dorsal alitrunk reticulate-rugulose, the rugulae more strongly developed than on the head but still blunt and with the same beaded appearance. Petiole dorsum with traces of rugular sculpture, the postpetiole and gaster unsculptured. All dorsal surfaces of head and body with numerous fine hairs. Colour medium to dark reddish brown.

T. quasirum and coillum are the species most closely related to ranarum , the three of them sharing a similar habitus but differing in detail. Thus, quasirum is a noticeably smaller species than ranarum with relatively larger eyes, and coillum has the petiole more sharply angulate and retains rugulose sculpture on the postpetiole.

Material examined

Madagascar: Perinet (W. L. Brown); Andasibe (= Perinet) (W. L. & D. E. Brown).