Camponotus rotrae, Rakotonirina & Fisher, 2022

Rakotonirina, Jean Claude & Fisher, Brian L., 2022, Revision of the Malagasy Camponotus subgenus Myrmosaga (Hymenoptera, Formicidae) using qualitative and quantitative morphology, ZooKeys 1098, pp. 1-180 : 1

Camponotus rotrae sp. nov.

Figs 39A , 72

Holotype worker.

Madagascar: Province Fianarantsoa: PN Isalo, 9.1 km 354° N Ranohira, -22.48167, 45.46167, 725 m, gallery forest, ex rotten log, 27-31 Jan 2003 (Fisher, Griswold et al.) collection code: BLF07331, specimen code: CASENT0485625 (CAS).

Paratype.

1 major worker of same data as holotype but specimen coded as: CASENT0485628 (CAS).

Additional material examined.

Madagascar: Fianarantsoa: dry wash, 1 km E of PN Isalo Interpretive Center, -22.62667, 45.35817, 885 m, dry wash (R. Harin’Hala) (CAS); Horombe Region, District of Ihosy , PN Isalo, 900 m E of ANGAP Interpretation Center, -22.62667, 45.35817, 701 m, open area near stream ( Rin’Ha, Mike) (CAS); PN Andringitra, Forêt Ravaro 12.5 km SW Antanifotsy, -22.21167, 46.845, 1500-1800 m, montane rainforest, (S. Razafimandimby) (CAS); PN Isalo, 9.1 km 354° N Ranohira, -22.48167, 45.46167, 725 m, gallery forest (Fisher, Griswold et al.) (CAS); stream area, 900 m E of PN Isalo Interpretive Center, -22.62667, 45.35817, 750 m, open area near stream (R. Harin’Hala) (CAS) . Mahajanga: PN Ankarafantsika, Foret de Tsimaloto , 18.3 km 46° NE de Tsaramandroso, -16.22806, 47.14361, 135 m, tropical dry forest (Fisher, Griswold et al.) (CAS) . Toliara: FC Analavelona, 29.2 km 343° NNW Mahaboboka , -22.675, 44.19, 1100 m, montane rainforest (Fisher, Griswold et al.) (CAS) .

Diagnosis.

In full-face view, lateral margins of head anterior to eye level diverging posteriorly; anterior clypeal margin truncate; two pairs of white spots present on second and third abdominal tergites; pronotum, mesonotum, and propodeum not forming separate convexities, metanotal groove not depressed; propodeum immediately in junction with promesonotum; propodeal dorsum straight.

Description.

Minor worker. In full-face view, lateral margin of head diverging posteriorly towards level of eye, rounding evenly to posterior margin behind eye level; eye protruding and small (EL/CS: 0.24 ± 0.01; 0.22-0.26), not interrupting lateral cephalic border, level of its posterior margin located approximately at posterior 1/4 of head (PoOc/CL: 0.25 ± 0.01; 0.23-0.25); frontal carinae wide (FR/CS: 0.31 ± 0.01; 0.29-0.33), posteriorly diverging, distance between them larger than their smallest distance to eye; clypeus with anterolateral angle and straight anteromedian margin; two apical teeth of mandible normally distant; antennal scape relatively long (SL/CS: 1.19 ± 0.05; 1.08-1.27). Promesonotum weakly convex, mesopropodeum almost flat; metanotal groove barely visible or indistinct; propodeal dorsum nearly straight, its junction to declivity bluntly angulate; propodeal dorsum two and a 1/2 times as long as declivity. Petiolar node short and high, with dorsal margin inclined posteriorly and rounding to anterior margin; anterior and posterior faces at almost the same height; femur of hind leg rounded axially, not twisted near base.

First and second gastral tergites with a pair of white spots; lateral margin of head without erect hairs; two erect hairs present near posterior margin of head; antennal scape covered only with appressed hairs; pronotum with few erect hairs; mesonotum with one pair of erect hairs; posterodorsal corner of propodeum with two pairs of erect hairs. Body color shining brown to dark-brown; apical portion of appendages with lighter color.

Major worker. Differing from minor worker in the following characters: larger head (CS: 2.29 ± 0.17; 2.03-2.42; CWb/CL: 1.03 ± 0.01; 1.02-1.04) with more or less straight posterior margin; apical 1/5 of antennal scape surpassing posterior cephalic margin; in lateral view, mesosoma characterized by even convexity of pronotum and mesonotum, separated from propodeum by distinct metanotum; propodeal dorsum strongly sloping to declivity surface and two and a 1/2 times as long as declivity.

Distribution and biology.

Endemic to Madagascar, C. rotrae is geographically limited to the south-central high plateau of Madagascar. The species occupies montane rainforests of the PN Andringitra, gallery forest and grassland of the PN Isalo, savannah woodland of Itremo, and relict montane rainforest of the Forêt Classée d’Analavelona (Fig. 72D ). The species nests mainly in rotten logs and under stones. Based on collection data, workers most often forage on the ground and rarely on lower vegetation.

Discussion.

See discussion under C. gibber . The qualitative morphological distinction of C. rotrae from other species has been confirmed by multivariate analyses of quantitative morphology. The cluster of C. rotrae samples in the dendrogram of the NC-clustering is supported by LDA with a classification success of 100%.

Etymology.

The species name rotrae is a non-Latin singular noun used in apposition.

Figures

Figure 39. Mesosoma in lateral view A C. rotrae (CASENT 0485625) B C. quadrimaculatus (CASENT 0121629).

Figure 72. Camponotus rotrae A lateral view B head in full-face view C dorsal view of holotype minor worker CASENT 0485625 D distribution map.