Aptinoma mangabe Fisher, 2009

Fisher, B. L., 2009, Two new dolichoderine ant genera from Madagascar: Aptinoma gen. n. and Ravavy gen. n. (Hymenoptera: Formicidae)., Zootaxa 2118, pp. 37-52 : 40-43

Aptinoma mangabe Fisher sp. n.

Figures: worker 3, 7a, queen 4, male 5

Type Material: Holotype: major worker, MADAGASCAR, Province Toamasina, Nosy Mangabe, 7.43 km S Maroantsetra , 15.4973°S, 49.76223°E, 5 m. 27 July 2007, ex dead twig above ground, littoral rainforest edge (coll. J.J. Rafanomezantsoa.) collection code: BLF17925 , pin code: CASENT0130146 ( CASC). Paratypes: 1 minor worker, 1 major worker, ergatoid queen, male with same data as holotype but pins coded CASENT0130148 , CASENT0192285 , CASENT0175008 , CASENT0130147 , respectively ( BMNH, CASC, MCZC) .

Major worker measurements: maximum and minimum based on all specimens, n=5, HL 0.54-0.57, HW 0.53-0.56, CI 99-102, ED 0.10-0.11, SL 0.39-0.41, SI 70-75, WL 0.57-0.64, FL 0.47-0.49, PW 0.34-0.37.

Minor worker measurements: maximum and minimum based on all specimens, n=5, HL 0.42-0.46, HW 0.37-0.42, CI 86-96, ED 0.09, SL 0.38-0.41, SI 97-103, WL 0.48-0.54, FL 0.41-0.45, PW 0.22-0.29.

With characters described in the genus diagnosis for major and minor workers: Apical teeth on mandible followed by 4-6 denticles; basal margin with minute, serrate teeth. Anterior clypeal margin with distinct shallow median impression; medial clypeal margin with three pairs of setae arched anteriorly over mandibles; additional pair of setae on clypeus, posterior of clypeal margin, directed anterodorsally. Scape surpassing posterior margin of head in full-face view in minors, not surpassing margin in majors. In dorsal view, lateral margin of pronotum with blunt angle at widest point. Metanotal groove in profile not impressed; propodeum in profile with dorsal and declivitous surfaces not differentiated, forming single evenly rounded surface without trace of angle at junction with declivity. Body yellow to orange.

A. mangabe can be separated from A. antongil by color and shape of propodeum and metanotal groove as outlined in the key to species. Differences in minor workers are discussed under antongil .

Queen (ergatoid) measurements: n=1. HL 0.61, HW 0.59, CI 97, ED 0.15, SL 0.44, SI 75, WL 0.82, FL 0.57, PW 0.44.

All main morphological characters of the major worker are duplicated in the queen caste. In the ergatoid queen, ocelli are present and the mesoscutellum is distinct. Metanotum indistinguishable, but metanotal groove distinctly wider than that of workers.

Male measurements: maximum and minimum based on n=3: HL 0.40-0.43, HW 0.54-0.57, CI 127-137, ED 0.22-0.25, SL 0.21, SI 37-39, WL 0.74-0.78, FL 0.52-0.55.

In profile, inner margin of eye convex, not flat. Antenna with 13 articles. Scape not reaching posterior margin of head, shorter than flagellar segments 1+2+3. Pedicel conical. First flagellar article cylindrical, straight, articles 1 and 2 twice as long as broad. Anteromedial clypeal margin with central concavity. Anterior clypeal margin with several pairs of straight setae projecting anteriorly, central pair longer than the setae at lateral margins. Just posterior to anterior margin, a single pair of suberect setae projecting anterodorsally. Posterior clypeal margin convex between antennal socket cavities. Palpal formula 6:3 (not confirmed with dissection). Mandible with apical tooth followed by a series of 15 or more minute denticles that decrease in size towards the basal margin. An uninterrupted curve between masticatory and basal margins. Propodeal angle indistinct; declivitous and dorsal faces of propodeum forming a single convexity. Petiole in profile with distinct scale, angled dorsally and strongly inclined anteriorly with anterior margin shorter than posterior margin. Venter of petiole with weakly developed lobe. Pygostyles present.

Distribution and biology. Distribution is limited to forests around Antongil Bay including the island of Nosy Mangabe and the adjacent forest of the Masoala Peninsula. Specimens were collected from dead twigs or vines, or foraging in the canopy. Males were collected in colonies in April and July. The only queen collected was an ergatoid.

Additional material examined for Aptinoma mangabe : In addition to the type material, specimens from 8 additional collecting events from the following 4 localities were examined in this study. MADAGASCAR, Province Toamasina:

P.N. Masoala, 40 km 154° SSE Maroantsetra, 150 m, 15.72667°S, 49.95667°E, (A. Dejean & B. Rajemison), 14 October 2001, rainforest, canopy. Tampolo, Masoala Peninsula, 40.4 km 154° SSE Maroantsetra, 30 m, 15.73°S, 49.96°E, (B.L.Fisher, & H.J.Ratsirarson), 28 November 2001, rainforest, canopy collection codes: BLF04698 BLF04713, BLF04717. Nosy Mangabe, 7.43 km S Maroantsetra, 5 m, 15.4973°S, 49.76223°E, (C. Ranaivo & C. E. Randrianandrasana), littoral rainforest edge, collection codes: BLF17931, 27 July 2007, on low vegetation; BLF18015, 31 August 2007, ex dead twig above ground. Nosy Mangabe, <5 m, 15.5°S, 49.76667°E, (P.S.Ward), collection code: PSW10346, 20 April 1989, rainforest edge, ex dead twig of vine.