Camponotus mifaka Rakotonirina, Csosz & Fisher

Rakotonirina, Jean Claude, Csosz, Sandor & Fisher, Brian L., 2016, Revision of the Malagasy Camponotusedmondi species group (Hymenoptera, Formicidae, Formicinae): integrating qualitative morphology and multivariate morphometric analysis, ZooKeys 572, pp. 81-154 : 122-124

Taxon classification Animalia Hymenoptera Formicidae

Camponotus mifaka Rakotonirina, Csosz & Fisher sp. n. Figures 14A, 27, 42

Holotype worker.

Madagascar, Antsiranana, Parc National de Marojejy, 25.4 km 30° NNE Andapa, 10.9 km 311° NW Manantenina, -14.445, 49.735, 2000 m, montane shrubland, ex root mat, ground layer, 24 Nov 2003 (B.L. Fisher et al.) collection code BLF09351, specimen code CASENT0217301 (CASC).

Paratypes.

8 workers same data as holotype but with the following specimen codes: CASENT0486999, CASENT0487000, CASENT0487001, CASENT0746965, CASENT0746966, CASENT0746967, CASENT0746970, CASENT0746971 (BMNH, MHNG, MSNG, CASC).

Additional material examined.

MADAGASCAR: Province Antsiranana: Parc National Marojejy, 25.4 km 30° NNE Andapa, 10.9 km 311° NW Manantenina, -14.445, 49.735, 2000 m, montane shrubland, (B.L. Fisher) (CASC).

Diagnosis.

In profile, anterior and posterior margins of petiolar node convex; in profile, propodeal dorsum and declivitous surface separated by blunt angle; in dorsal view, mesonotum less than twice as broad as long; mesopleuron with propodeal sur face together distinctly wider than lateral portion of pronotum; in profile, propodeal dorsum roughly as long as declivitous margin; dorsum of head and mesosoma densely and finely reticulate punctate; dorsum of mesosoma covered with numerous erect hairs and pubescence.

Description.

Minor worker (Figs 14A, 27). In full-face view, head elongate (CWb/CL: 0.9-0.95), diverging posteriorly; posterior margin slightly convex. Level of posterior ocular margins located generally on posterior fifth portion of head (PoOc/CL: 0.21-0.25). Anterior margin of clypeus straight; posterior margin medially notched. Mandible triangular, apical margin armed with six sharp teeth. Antennal scape relatively long (SL/CS: 0.92-1.02), more than one third of apical portion of antennal scape extending beyond posterior cephalic margin. Promesonotum slightly, broadly convex, dorsum and sides separated by margination; anterodorsal angle of pronotum projecting anteriorly into a ridge. In dorsal view, mesonotum less than twice as broad as long; posterodorsal angle without extended lobe. In lateral view, propodeum not strongly compressed anteroposteriorly; dorsal portion of propodeum raised and abruptly strongly sloping posteriorly; junction to declivity marked by blunt angle; dorsolateral portion of propodeum marginate, distance between meso-metapleural suture and dorsolateral margin of propodeum remaining the same along dorsolateral margin of propodeum; propodeal spiracle located on declivitous surface. Width of meso-metapleuron and propodeal lateral portion together noticeably greater than width of lateral portion of pronotum. In side view, maximum width of procoxa larger than width of meso-metapleuron. In profile, anterior and posterior margins of petiolar node convex. Junction of abdominal segments III and IV without visible constriction.

Dorsum of head anteriorly finely and densely reticulate punctate, the punctures deepening posteriorly. Mandible smooth and shining between scattered punctures. Mesosoma dorsum finely and densely reticulate punctate. Gastral tergites smooth and shining apart from shallow punctures from which erect hairs or pubescence arise. Pairs of whitish erect hairs numerous on dorsum of head and mesosoma; hairs randomly scattered on gastral tergites. Erect hair present on declivitous surface above propodeal spiracle. Near posterolateral margins to posterodorsal corner of petiolar node with a row of whitish erect hairs. Much shorter and sparse erect hairs organized transversely on anterior and posterior portions of each gastral tergite; pubescence reduced. Integument generally black; basal portion of legs dark brown and becoming lighter towards metatarsi; antennal scape basally brown and apically black to dark brown.

Major worker. With characteristics of minor worker, except: head larger relative to whole body size (ML/CS: 1.29-1.35); shape relatively subquadrate (CWb/CL: 0.93-0.95) with lateral margins slightly converging to base of mandibles; posterior margin more or less straight. Eyes positioned more on frontal portion of head, level of posterior ocular margins located approximately on posterior fourth portion of head (PoOc/CL: 0.23-0.25); mandible strong; one sixth of apical portion of antennal scape surpassing posterior cephalic margin (SL/CS: 0.92-0.96). Scattered punctures on dorsolateral portion of head near base of mandible.

Distribution and biology.

Known only from the montane shrubland of the Parc National Marojejy (Fig. 42), Camponotus mifaka forages in leaf mold and rotten wood and nests under root mats in the ground.

Discussion.

Camponotus mifaka might be confused with Camponotus edmondi , Camponotus orombe , and Camponotus tafo because of the dense and fine reticulate-punctate sculpture on the dorsum of the head and mesosoma; however, the latter three species have a reduced number of erect hairs on the dorsum of the mesosoma, particularly on the promesonotal dorsum.

Based on the information provided by the NC-clustering method, the cluster of Camponotus mifaka contains one sample of Camponotus varatra , but is classified successfully at 100% by LDA. The integration of this successful classification with the results from qualitative morphological study and biological evidence underscores the robustness of the taxonomic determination for this species. Camponotus varatra differs morphologically from Camponotus mifaka by its imbricate sculpture and biologically by its nesting sites in dead twigs or branches above the ground.