Tetraponera longula (Emery)

Ward, Philip S., 2022, The ant genus Tetraponera (Hymenoptera: Formicidae) in the Afrotropical region: taxonomic review and key to species, Zootaxa 5102 (1), pp. 1-70 : 40

Tetraponera longula (Emery)

( Fig. 18 )

Sima Sahlbergi var. longula Emery 1895a: 340 . Syntypes, 2 workers, Diego-Suarez, Madagascar (C. Alluaud) ( MSNG, MNHN) [examined] . 1 syntype worker from MSNG imaged on AntWeb: CASENT0102031 ; 1 syntype worker from MNHN imaged on AntWeb: CASENT0101395 .

Sima sahlbergi r. deplanata Forel 1904: 375 . Holotype worker (by monotypy), Fort Dauphin (Sikora) (ZMAS) [examined]. Syn. nov.

Sima (Tetraponera) sahlbergi var. longula Emery ; Emery 1921: 28. Combination in Sima (Tetraponera) .

Tetraponera sahlbergi var. longula (Emery) ; Wheeler 1922c: 1016. Combination in Tetraponera .

Tetraponera sahlbergi longula (Emery) ; Ward 1990: 488. Subspecies of T. sahlbergii .

Tetraponera longula (Emery) ; Chomicki et al. 2015: figure S1. Raised to species; placement in molecular phylogeny.

Sima (Tetraponera) sahlbergi subsp. deplanata Forel ; Emery 1921: 28. Combination in Sima (Tetraponera) .

Tetraponera sahlbergi subsp. deplanata (Forel) ; Wheeler 1922c: 1016. Combination in Tetraponera .

Worker measurements (n=12). HW 0.67–0.81, HL 0.85–1.04, LHT 0.62–0.74, CI 0.73–0.80, FCI 0.09–0.12, REL 0.28–0.31, REL2 0.37–0.40, SI 0.58–0.62, SI3 1.43–1.69, FI 0.40–0.47, PLI 0.46–0.57, PWI 0.40–0.48, LHT/HW 0.89–0.96, CSC 2, MSC 2–7.

Worker diagnosis. Small- to medium-sized species, with somewhat elongate head, and eyes of moderate size (see ocular indices); minimum distance between frontal carinae slightly exceeding basal scape width (FCI 0.09– 0.12); scape moderately long, greater than one-half head width and less than one-half head length (SI 0.58–0.62, SI2 0.42–0.49); median clypeal lobe with prominent median tooth and paired lateral teeth, 0.02–0.05 mm long; flanking this are paired, outer lateral teeth that are usually smaller, and often reduced to slight protrusions ( Fig. 18a ); profemur moderately robust (FI 0.40–0.47); mesosoma with a differentiated, transverse metanotal plate, about one third the length of the mesonotum; dorsal face of propodeum laterally submarginate, notably longer than declivitous face and rounding into the latter; petiole slender (PLI 0.46–0.57, PWI 0.40–0.48), with a well differentiated anterior peduncle, the node with relatively shallow and similar anterodorsal and posterodorsal faces, as seen in profile ( Fig. 18b ); postpetiole longer than broad. Integument shiny to sublucid, with weak reticulation and scattered punctures, the punctures rather fine on all surfaces. Standing pilosity sparse on head, with 1 pair of supraocular setae (CSC = 2); mesosoma typically with one pair of rather long standing hairs on the pronotal corners, and a pair of standing hairs on the mesonotum, but occasionally more or fewer (MSC 2–7); standing pilosity absent from dorsal face of propodeum. Dark brownish-black, antennae and distal portions of legs lighter.

Comments. This worker of this species can be recognized by a combination of its small to medium size, dark color, well developed clypeal teeth, raised metanotal plate (lateral view), and slender petiole (PLI 0.46–0.57). T. longula is most closely related to a similar, undescribed sister species with a more robust petiole (PLI 0.58–0.67), referred to as “ Tetraponera longula _cf” in Chomicki et al. (2015). Tetraponera longula differs from T. sahlbergii , the species with which is has been associated nomenclaturally, by its prominent clypeal teeth, shinier integument, and elongate propodeum with submarginate basal face.

Distribution and biology. T. longula has a distribution that spans the length of the island of Madagascar. It is confined to rainforest and rainforest edge, where it nests in dead twigs. The type locality is “Diego Suarez” but presumably these specimens, collected by Alluaud, were taken in a nearby rainforest location such as Montagne d’Ambre.

Figures

FIGURES 16–18. Tetraponera allaborans group, workers, full-face (dorsal) view of head (a) and lateral profile of body (b). 16, T. tessmanni, Cameroon (CASENT0794354); 17, T. hysterica, Madagascar (CASENT0012842); 18, T. longula, Madagascar (CASENT0012843). Images from AntWeb (www.antweb.org); photographers Matthew Prebus (16), April Nobile (17, 18).