Camponotus dromedarius Forel

Rakotonirina, Jean Claude & Fisher, Brian L., 2018, Taxonomic revision of the Malagasy Camponotus subgenus Mayria (Hymenoptera, Formicidae) using qualitative and quantitative morphology, Zootaxa 4438 (1), pp. 1-58 : 25

Camponotus dromedarius Forel

( Figures 9A , 11A , 16 , 22 )

Camponotus dromedarius Forel, 1891: 65 (minor worker), 66 (major worker), 67 (m.), 72 (key). Lectotype minor worker, present designation, Madagascar, Imerina et environs d’Antananarivo, Forêt d’Analamainty, ex bamboo internodium (Camboué), AntWeb CASENT0101534 (MHNG). Paralectotype worker and male of same data as lectotype but with respective specimen codes: CASENT0101531 (MHNG), CASENT0101422 (MNHN) [examined]. [Combination in Camponotus (Myrmocamelus) : Forel, 1914: 270; in Camponotus (Myrmosaga) : Emery, 1920: 257; in Camponotus (Mayria) : Emery, 1925: 122].

Diagnosis. Median portion of clypeus not longitudinally carinate; mandible with six teeth; in lateral view, mesosoma short and high, its dorsal outline continuously arched in a dome-like structure; propodeal declivity inclined posteriorly; in lateral view, propodeal dorsum straight, without excision; petiolar node higher than long; anterior clypeal margin broadly convex.

Description. Minor worker. In full-face view, head longer than broad (CWb/CL: 0.80±0.07; 0.72–1.05), lateral margins roughly straight and slightly converging anteriorly; posterior margin more or less straight. Anteromedian clypeal margin straight with broadly convex lateral angle. Eyes not breaking lateral outlines of head, their posterior margins located well behind the mid-length of the head (PoOc/CL: 0.34±0.02; 0.31–0.39). Mandible triangular, masticatory margin with six sharp teeth. Antennal scape long, roughly its distal half extending beyond posterior cephalic border. In lateral view, mesosoma evenly convex, its dorsal outline continuously arched in a dome-like structure; pronotum with anterodorsal margin; pronotum and mesonotum separated by a shallow, broad angle; junction of propodeal dorsum and declivity round. Petiolar node higher than long.

Whitish, erect, filiform hairs abundant and pubescence present on dorsum of head, mesosoma, petiolar node, and gastral segments. Body color generally black or mesosoma dark brown with orange spots.

Major worker. Characteristics the same as minor worker, except the enlarged head (CS: 1.64±0.12; 1.48– 1.82; CWb/CL: 0.93±0.04; 0.86–0.98); the more strongly built mandible; apical third of antennal scape surpassing posterior cephalic margin; metanotum visible; propodeal dorsum convex and its junction to declivity broadly angulate; petiolar node much higher than long.

Discussion. Members of C. dromedarius can be separated from similar species in the group such as C. pulcher and C. lamosy by its larger body size (CL: 1.19–1.84), the straight propodeal dorsum, and the higher than long petiolar node. It can be distinguished from other species by the absence of a median longitudinal carina on its clypeus, the dome-like structure of its mesosoma, and the generally black body color which occasionally has a dark brown mesosoma with orange spots.

The taxonomic categorization of C. dromedarius based on study of qualitative morphology is supported by the NC-clustering. Separation of this species is confirmed by LDA with 100%.

Distribution and biology. Camponotus dromedarius is only known from Madagascar. Members of the species have been found mostly at altitudes between 800–1400 m in the central region, relict montane rainforest in the central west, and eastern montane rainforests. The species nests in rotten logs and rotting tree stumps and forages on the ground and low vegetation in these habitats.

Additional material examined. Province Antananarivo: [Antananarivo, Museum Paris, Grandidier 1893], Ambatomanjaka, Miarinarivo, 1398 m, -18.705147, 46.825284, (Camboué) ( MNHN); [ Madagascar], Ambatomanjaka, Miarinarivo, 1344 m, -18.766947, 46.869107 ( NHMB); 3 km 41° NE Andranomay, 11.5 km 147° SSE Anjozorobe, 1300 m, -18.47333, 47.96, montane rainforest, (Fisher, Griswold et al.) ( CASC); Province Antsiranana: Galoko chain, Mont Galoko, 980 m, -13.5888, 48.72864, montane forest, (B.L. Fisher et al.) ( CASC); Parc National de Marojejy, Antranohofa, 26.6 km 31° NNE Andapa, 10.7 km 318° NW Manantenina, 1325 m, -14.44333, 49.74333, montane rainforest, (B.L. Fisher) ( CASC); Parc National Montagne d'Ambre [1 st campsite ], 960 m, -12.51444, 49.18139, rainforest, (R. Harin'Hala) ( CASC); Province Fianarantsoa: [Imerina], Fahizay, Ambositra, 1317 m, -20.5, 47.333332, (Camboué) ( MHNG); 2 km W Andrambovato, along river Tatamaly, 1075 m, -21.51167, 47.41, montane rainforest, (B.L. Fisher et al.) ( CASC); Parc National Befotaka- Midongy, Papango 28.5 km S Midongy-Sud, Mount Papango, 1250 m, -23.84083, 46.9575, montane rainforest, (B.L. Fisher et al.) ( CASC); Parc National de Ranomafana, Vatoharanana River, 4.1 km 231° SW Ranomafana, 1100 m, -21.29, 47.43333, montane rainforest, (Fisher, Griswold et al.) ( CASC); Province Toamasina: [Nosi be (Imerina)], Anosibe An'ala, Anosibe, 660 m, -19.433332, 48.216667, (Sikora) ( MHNG); 6.9 km NE Ambanizana, Ambohitsitondroina, 825 m, -15.58506, 50.00952, rainforest, (B.L. Fisher) ( CASC); Corridor Forestier Analamay- Mantadia, Ambatoharanana, 1013 m, -18.80388, 48.40506, rainforest, (B.L. Fisher et al.) ( CASC); Corridor Forestier Analamay-Mantadia, Ambatoharanana, 968 m, -18.80424, 48.40081, rainforest, (B.L. Fisher et al.) ( CASC); Province Toliara: 13 km NW Enkara, Res Andohahela, 1140 m, -24.55, 46.8, montane rainforest, (B.L. Fisher) ( CASC); 13 km NW Enkara, Res Andohahela, 1280 m, -24.55, 46.8, montane rainforest, (B.L. Fisher) ( CASC); 13 km NW Enkara, Res Andohahela, 1300 m, -24.55, 46.8, montane rainforest, (B.L. Fisher) ( CASC); 6 km ESE Imonty, Réserve Andohahela, 1200 m, -24.85, 46.75, rainforest, (P.S. Ward) ( PSWC); Parc National d'Andohahela, Col du Sedro, 3.8 km 113° ESE Mahamavo, 37.6 km 341° NNW Tolagnaro, 900 m, -24.76389, 46.75167, montane rainforest, (Fisher-Griswold Arthropod Team) ( CASC); Réserve Spéciale d'Ambohijanahary, Forêt d'Ankazotsihitafototra, 35.2 km 312° NW Ambaravaranala, 1050 m, -18.26667, 45.40667, montane rainforest, (Fisher, Griswold et al.) ( CASC); Réserve Spéciale Kalambatritra, Ambinanitelo, 1325 m, -23.4502, 46.45658, montane rainforest, (B.L. Fisher et al.) ( CASC); Réserve Spéciale Kalambatritra, Ampanihy, 1270 m, - 23.4635, 46.4631, montane rainforest, (B.L. Fisher et al.) ( CASC).

Figures

FIGURE 9. Mesosoma in lateral view. A: C. dromedarius (CASENT0496817). B: C. christi (CASENT0129791).

FIGURE 11. Mesosoma and petiole node in lateral view. A: C. dromedarius (CASENT0496817). B: C. pulcher (CASENT0191639).

FIGURE 16. Camponotus dromedarius minor worker CASENT0496817. A: lateral view. B: head in full-face view. C: dorsal view.

FIGURES 21–26. Distribution maps of Camponotus subgenus Mayria in Madagascar. Fig. 21: C. christi; Fig. 22: C. dromedarius; Fig. 23: C. foersteri; Fig. 24: C. lamosy; Fig. 25: C. liandia, Fig. 26: C. lubbocki.