Tetraponera grandidieri
Creators: name: Ward, P. S.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Formicidae
Tetraponera
Tetraponera grandidieri

description: Diagnosis of the Tetraponera grandidieri group
(modified from Ward 2006)
Worker diagnosis. Medium to large species (HW 0.95-1.59, HL 1.05-2.01, LHT 1.05-1.83); masticatory margin of mandible with four teeth; basal margin with 0-1 teeth and subequal in length to masticatory margin; labrum with a pair of tubercles closely flanking the midline near the proximal margin but lacking a median tubercle; palp formula 6,4; anteromedial margin of clypeus crenulate or emarginate; distance between frontal carinae exceeding basal scape width (FCI 0.11-0.18), scape length three-quarters or more of head width (SI 0.72-0.83); eye length about one-third of head length (REL 0.28-0.36); head capsule with three distinct ocelli; pronotum laterally marginate, but not strongly so; mesopropodeal impression well developed (Figs 5, 6); petiole relatively long (PLI 0.49-0.59, PWI 0.40-0.65); posteroventral margin of petiole lying adjacent to helcium venter; metabasitarsal sulcus present; legs long and slender (FI 0.28-0.36, LHT/HL 0.85-1.12); appressed pubescence sparse on abdominal tergite 4; standing pilosity uncommon (CSC 2-3, MSC 1-6), absent from mesonotum, propodeum, and extensor surfaces of the tibiae. Orange to reddish-brown, head concolorous or darker; gaster and portions of femora may also be infuscated.
Comments. Distinctive features of the worker caste of the T. grandidieri group include the relatively large body size, long legs and antennal scapes, presence of three ocelli, deeply impressed mesopropodeal impression, and conspicuous orange to reddish-brown body coloration. Other Malagasy Tetraponera species have shorter scapes and legs (SI 0.40-0.70, LHT/HL 0.58-0.82), 0-2 ocelli on the head, a shallower mesopropodeal impression, and usually darker body color. Additional differences between the T. grandidieri group and the other four species groups of Afrotropical Tetraponera are given in Ward (2006).
Synonymie list of species
T. grandidieri (Forel 1891: 203)
= T. grandidieri hildebrandti (Forel 1891: 203) syn. n.
T. hespera sp. n.
T. hirsuta sp. п.
T. inermis sp. п.
T. manangotra sp. n.
T. merita sp. n.
T. variegata (Forel 1895: 487) stat. n.
KEY TO SPECIES BASED ON THE WORKER CASTE
1 Basal margin of mandible with a prominent tooth, in addition to four teeth on the masticatory margin (Fig. 1); anterior clypeal margin deflected ventrally; widespread in eastern and northern Madagascar ......................... merita
- Basal margin of mandible lacking tooth, masticatory margin with four teeth (Fig. 2); anterior clypeal margin directed forward, not deflected ventrally ............. 2
2(1) Petiole broad (PWI 0.61-0.65, DPW/HW 0.50-0.53), subtriangular in dorsal view, and with a relatively short, thick anterior peduncle (Fig. 20); larger species, HW 1.48-1.58, LHT 1.64-1.76; known only from extreme southern Madagascar ....... manangotra
Petiole more slender (PWI 0.40-0.53, DPW/HW 0.30-0.40), obovate, and with a thin, elongate anterior peduncle (e.g., Figs 14, 16, 18); smaller species, HW 0.95-1.44, LHT 1.05-1.59; widespread .......................................... 3
3(2) Scape with conspicuous suberect and subdecumbent hairs (Fig. 13); body tricolored: metasoma, appendages, and ventral margin of mesosoma orange, most of mesosoma reddish-brown, and head dark brownish black; endemie to Manongarivo Massif - hirsuta
- Most hairs on scape appressed or decumbent, and generally inconspicuous, except
those at the apex (e.g., Fig. 9); body color variable but usually without preceding
tricolor pattern ................................................... 4
4(3) Metanotal spiracle not protruding above the profile of the mesosoma, as seen in lateral view (Fig. 5); head broad (CI 0.88-0.97); head and mesosoma reddish-brown, metasoma and appendages paler; widespread in eastern Madagascar..... inermis
- Metanotal spiracle more or less protruding above the profile of the mesosoma, as seen in lateral view (Fig. 6); head usually more elongate (CI 0.77-0.90); color variable .... 5 5(4) Dorsum of propodeum laterally compressed, the propodeum appearing subtriangular in posterior view (Fig. 3); body concolorous orange-brown; northern Madagascar............................. hespera, in part (Ankarana population)
- Dorsum of propodeum more broadly rounded, the propodeum appearing dome-
shaped in posterior view (Fig. 4); color variable .......................... 6
6(5) Legs uniformly light orange-brown, femora lacking conspicuous black banding; body usually bicolored, such that dark head contrasts with lighter orange-brown mesosoma and metasoma (Fig. 8), less commonly unicolorous orange; widespread and variable species ........................................ grandidieri
- Legs light orange-brown, with contrasting black bands on the distal portions of the mesofemur and metafemur (Figs 10, 22); body concolorous or bicolored (in latter case both head and gaster are dark brownish-black) ....................... 7
7(6) Body concolorous yellow brown or orange brown (Fig. 10); northwestern Madagascar............................ hespera, in part (most populations)
- Body bicolored, head and gaster dark brown and contrasting with the lighter mesosoma (Fig. 22); eastern Madagascar.......................... variegata
description: Published as part of Ward, P. S., 2009, The ant genus Tetraponera in the Afrotropical region: the T. grandidieri group (Hymenoptera: Formicidae)., pp. 285-304 in Journal of Hymenoptera Research 18 on pages 287-288