Camponotus maculiventris

Samples for C. maculiventris have been generally recorded from the rainforests of the east and the montane rainforests of the center and east of Madagascar and are occasionally found in the littoral rainforest of the northeast. Along its eastern distribution, the geographic range is from Sakalava Beach in the northernmost to the Parc National Andasibe in the center and down to Anosyenne Montain in the southernmost region. Camponotus maculiventris forages most frequently on lower vegetation and in leaf litter but rarely on the forest floor. Nest series have been collected frequently from dead branches above the ground and rotten logs but occasionally from under stones and root mats in the ground or on rocks.

Identification
A member of the subgenus Mayria (see diagnosis). Rakotonirina and Fisher (2018) - Median portion of clypeus without median longitudinal carina; mandible armed with six teeth; anteromedian margin of clypeus not bordered by a lamella; in lateral view, length of posterior portion of propodeal dorsum measured from the end of line connecting anteriormost point of pronotal shield and metathoracic spiracle as long as height of declivity; petiole node not flattened anteroposteriorly, its dorsal margin distinctly broadly convex; body mostly black, legs with at least trochanters and distal portions of coxae yellowish to white; hind tibia shorter than hind femur.

Camponotus maculiventris is one of the most widespread species in the subgenus Mayria and shows important morphological variation in the form of the mesosoma, overall body size, and leg color.

Camponotus maculiventris may be difficult to differentiate from Camponotus pulcher in that both species have a short and high mesosoma and lack the median longitudinal carina on the clypeus, the straight propodeal dorsum, and the shape of the petiolar node. But in C. pulcher the anteromedian margin of the clypeus is slightly concave medially, the head is black, abdominal segments 3 and 4 are yellow-orange with remaining segments mostly black, and the mesosoma is reddish-orange. Workers of C. maculiventris can also be confounded with those of Camponotus foersteri and Camponotus mainty, but in C. foersteri the propodeal dorsum is three times as long as the height of the declivity and the hind tibia is as long as hind femur. Members of C. mainty have an entirely black to reddish-black body and legs, and a flattened petiolar node.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  maculiventris. Camponotus christi var. maculiventris Emery, 1895f: 344 (w.q.) MADAGASCAR.
 * Combination in C. (Mayria): Emery, 1925b: 122.
 * Subspecies of christi: Emery, 1896d: 373 (in list); Forel, 1910a: 21; Wheeler, W.M. 1922a: 1045; Emery, 1925b: 122; Bolton, 1995b: 110.
 * Status as species: Rakotonirina & Fisher, 2018: 39.

Worker
Rakotonirina and Fisher (2018) - Minor. In full-face view, head elongate, lateral margin slightly convex and weakly diverging posteriorly, rounding to a more or less straight posterior margin. Anterior margin of clypeus broadly convex, angle absent between lateral and anteromedian margins; median longitudinal carina lacking. Eyes not breaking lateral outlines of head; their posterior margins located well behind the mid-length of the head (PoOc/CL: 0.32±0.01; 0.29–0.36). Mandible triangular, apical margin with six sharp teeth. Antennal scape long, about its apical half surpassing the posterior cephalic margin. In lateral view, either pronotum, mesonotum, and propodeal dorsum forming even convexity or pronotum and mesonotum forming separate convexity and propodeal dorsum straight, joining declivity surface at a broad angle. Propodeal dorsum about twice as long as height of declivity; height of mesosoma taken from posteroventral corner of pronotum to highest point of mesonotum less than twice the height to level of metathoracic spiracle; propodeal spiracle rounded. Hind tibia shorter than hind femur. Petiolar node as high as long, dorsal margin forming broad angle with anterior and posterior faces.

Dorsum of head covered with numerous yellowish, elongate, erect hairs; pronotum, mesonotum, and posterodorsal angle of propodeum each with a pair of erect hairs; petiolar node with two pairs of erect hairs near its posterodorsal angle; pubescence short and sparse. Head mesosoma, petiole, and gastral segments black to brown and darker in color relative to appendages. Anterior half of second gastral tergite and first three sternites with lighter spot; trochanter and at least distal half of coxa whitish-yellow; femur and tibia whitish-yellow with dark brown spots on proximal and apical portion; tarsus and antennae dark brown basally and lighter in color apically.

Major. With characteristics of minor worker, except: enlarged head, with concave posterior margin; apical fourth of antennal scape surpassing posterior cephalic margin; robust mesosoma, metanotum distinctly visible; petiolar node higher than long, its dorsal margin inclined posteriorly from shorter anterior face towards much longer posterior face.

References based on Global Ant Biodiversity Informatics

 * Emery C. 1886. Saggio di un catalogo sistematico dei generi Camponotus, Polyrhachis e affini. Memorie della Reale Accademia delle Scienze dell'Istituto di Bologna 5: 363-382
 * Fisher B. L. 1997. Biogeography and ecology of the ant fauna of Madagascar (Hymenoptera: Formicidae). Journal of Natural History 31: 269-302.
 * Fisher B. L. 2003. Formicidae, ants. Pp. 811-819 in: Goodman, S. M.; Benstead, J. P. (eds.) 2003. The natural history of Madagascar. Chicago: University of Chicago Press, xxi + 1709 pp.
 * Rakotonirina J. C., and B. L. Fisher. 2018. Taxonomic revision of the Malagasy Camponotus subgenus Mayria Hymenoptera, Formicidae) using qualitative and quantitative morphology. Zootaxa 4438: 1-58.
 * Wheeler W. M. 1922. Ants of the American Museum Congo expedition. A contribution to the myrmecology of Africa. IX. A synonymic list of the ants of the Malagasy region. Bulletin of the American Museum of Natural History 45: 1005-1055