Camponotus chrislaini, Rasoamanana & Fisher, 2022

Rasoamanana, Nicole & Fisher, Brian L., 2022, A taxonomic revision of the Malagasy endemic subgenus Mayria of the genus Camponotus (Hymenoptera, Formicidae) based on qualitative morphology and quantitative morphometric analyses, ZooKeys 1081, pp. 137-231 : 137

Camponotus chrislaini sp. nov.

Figures 2D , 7C-D , 41D , 59

Holotype worker.

Madagascar, Province Antsiranana, Forêt d’Andavakoera, 21.4 km 75° ENE Ambilobe; 4.6 km 356° N Betsiaka, -13.11833, 49.23, 425 m, rainforest, ex rotten log, 16 December 2003 (BLF), collection code: BLF10296, specimen code: CASENT0498999 (CAS). Paratypes. Nine workers with the same data as holotype, CASENT0499000, CASENT0499001, CASENT0499002 (three workers in each pin) (CAS).

Worker diagnosis.

Camponotus chrislaini can be easily distinguished from the other members of the Camponotus efitra group by its mostly smooth and shiny sculpture; head more or less globose in full-face view; sigmoid frontal carina, and wavy propodeum dorsum.

Description of minor worker.

Medium-sized species. Absolute cephalic size (CS: 0.95 ± 0.17; 0.87-1.02). In full-face view, head ovoid (CWb/CL: 0.34 ± 0.03; 0.32-0.35); posterior margin rounded, lateral margin of head convex. Eyes circular, protruding, placed midway from the occipital corner (PoOC/CL: 0.12 ± 0.03; 0.11-0.13). Mandibles triangular with five teeth. Clypeus transversally trapezoidal, its anterior border broadly rounded, not angular. With head in full-face view, anterior clypeal margin rounded, not projecting (ClyL/GPD: 0.26 ± 0.03, 0.25-0.29). Antennal scape flattened and lobulated at the base, long, surpassing the occiput by the length of three basal funiculi (SL/CS: 0.46 ± 0.03; 0.45-0.48). In lateral view, anterodorsal corner of pronotum tuberculate, pronotal suture distinct, mesonotal suture distinctly impressed so that the anterior portion of propodeum is raised to a blunt edge in profile, and suture forms a concavity (MW/ML: 0.22 ± 0.02, 0.21-0.23; MPH/ML: 0.17 ± 0.02, 0.17-0.18). In lateral view, petiolar node nodiform, higher than long. Entire body, including mandible, smooth and shiny. One pair of standing hairs on angle formed by mesonotal dorsum and propodeum, head with scattered, subdecumbent, filiform brown hairs, scape with decumbent setae. Ant brownish; mandible, clypeus, and pronotum light brown; mid- and forecoxae, apical femora, basal tibiae, and apical portion of third and fourth tergite whitish.

Description of major worker.

Characteristics of minor workers, except: head quadrate with straight margins (CS: 1.67 ± 0.06, 1.57-1.74; CWb/CL: 0.92 ± 0.03, 0.90-0.96). Eyes circular, closed to the lateral margin (PoOC/CL: 0.29 ± 0.02, 0.27-0.31). In profile, clypeus distinctly truncate (ClyL/GPD: 0.92 ± 0.03, 0.86-0.94), its anterior margin with a short concavity in full-face view. Antennal scape same as minor but short, just reaching the occipital border (SL/CS: 0.77 ± 0.04, 0.74-0.83). Promesonotum forms a unique dome followed by an impressed mesonotal suture, dorsum of propodeum slightly concave near the propodeal angle. Anterior portion of head with widely spaced large punctures, a single puncture in the center of the vertex. Filiform brownish hair present on head and mesosoma dorsum, more abundant on malar area.

Distribution and biology.

Camponotus chrislaini is restricted to the northern portion of Madagascar (Fig. 70B ). This newly identified species prefers dry (tropical dry forest, dry forest, disturbed dry forest) as well as wet (montane forest and rainforest) habitats at moderate altitudes (below 1000 m). It was primarily collected from rotten logs, sifted litter, inside trees, or on branches above ground.

Discussion.

The new species is easily distinguishable from the Camponotus Mayria species, but morphologically is most similar to the unidentified species Camponotus MG098 from subgenus Camponotus Myrmonesites . The main character used to distinguish them is the form of the petiolar scale, as in the former the petiole is much thinner and its dorsal face forms a straight surface, while in the latter the petiole is thickened with the posterior face concave in dorsal view. Camponotus MG098 is also covered with plentiful setae which are scarce and widely distributed in C. chrislaini . The presence of C. chrislaini and C. MG098 in six localities (Sakaramy, Binara, Antsahabe, Analamerana-Ankavanana, Galoko, and Mont Kalabenono) suggests that they are reproductively isolated.

Additional material examined.

Province Antsiranana: Foret de Binara , 7.5 km 230° SW Daraina, -13.255, 49.61667, 375 m, tropical dry forest (B.L. Fisher) (CAS); Forêt d’ Antsahabe, 11.4 km 275° W Daraina, -13.21167, 49.55667, 550 m, tropical dry forest (B.L. Fisher) (CAS); Forêt d’ Andavakoera, 21.4 km 75° ENE Ambilobe; 4.6 km 356° N Betsiaka, -13.11833, 49.23, 425 m, rainforest (B.L. Fisher) (CAS); Res. Analamerana, 16.7 km 123° Anivorano-Nord, -12.80467, 49.37383, 225 m, tropical dry forest (B.L. Fisher) (CAS); Parc National Montagne d’Ambre, Fozalanana, -12.46637, 49.22157, 475m, dry forest (BLF) (CAS); Res. Ankarana, 7 km SE Matsaborimanga, -12.9, 49.11667, 150 m, tropical dry forest (PSW) (PSWC); Galoko chain, Mont Galoko, -13.58487, 48.71818, 520 m, rainforest (BLF) (CAS); Galoko chain, Mont Galoko, -13.5888, 48.72864, 980 m, montane forest (BLF) (CAS); Galoko chain, Mont Galoko, -13.58745, 48.71419, 38 m, rainforest (BLF) (CAS); Galoko chain, Mont Kalabenono, -13.63999, 48.67374, 498 m, rainforest (BLF) (CAS); Galoko chain, Mont Kalabenono, -13.64179, 48.67282, 643 m, rainforest (BLF) (CAS); Galoko chain, Mont Kalabenono, -13.64609, 48.67732, 937 m, rainforest (BLF) (CAS); Ampasindava, Andranomatavy Forest, -13.6648, 47.98702, 275 m, disturbed dry forest (BLF) (CAS); Reserve Spéciale d’Ambre, 3.5 km 235° SW Sakaramy, -12.46889, 49.24217, 325 m, tropical dry forest (FGAT) (CAS); Reserve Spéciale de l’Ankarana, 22.9 km 224° SW Anivorano Nord, -12.90889, 49.10983, 80 m, tropical dry forest (FGAT) (CAS); Ampasindava, Forêt d’Ambilanivy, 3.9 km 181° S Ambaliha, -13.79861, 48.16167, 600 m, rainforest (FGAT) (CAS) .

Figures

Figure 2. Morphological characters of workers of the subgenus Camponotus Mayria. Pronotum in lateral view A C. repens (CASENT 0217300) B C. maintikibo (CASENT 0062631) C C. alamaina (CASENT 0481799) Pronotal disc in dorsal view D C. repens (CASENT 0217300) E C. bevohitra (CASENT 0437238) F C. nossibeensis (CASENT 0191657) G C. ursus (CASENT 0217284) head of major in full-face view H C. ellioti (CASENT 0450893) I C. andrianjaka (CASENT 0159208) J C. repens (CASENT 0491956).

Figure 7. Morphological character of minor and major workers of C. efitra species group A, B Camponotus efitra (CASENT 0453926) A head of minor worker in full-face view B body in lateral view C head of major worker of Camponotus chrislaini (CASENT 0499002) D minor worker of Camponotus chrislaini (CASENT 0498999) in lateral view.

Figure 41. Antennal scape and mesopropodeum in lateral view A, B C. efitra (CASENT 0453926) C, D C. chrislaini (CASENT 0498999).

Figure 59. Camponotus chrislaini minor worker (CASENT 0498999) 1 body in lateral view 2 head in full-face view 3 body in dorsal view.

Figure 70. Distribution maps of C. antsaraingy species group A C. antsaraingy; C. efitra species group B C. chrislaini, C. ellioti species group C C. ellioti. D C. andrianjaka. E C. maintilany and C. madagascarensis species group F C. ivadia