Carebara polita (Santschi)

Fischer, Georg, Azorsa, Frank & Fisher, Brian L., 2014, The ant genus Carebara Westwood (Hymenoptera, Formicidae): synonymisation of Pheidologeton Mayr under Carebara, establishment and revision of the C. polita species group, ZooKeys 438, pp. 57-112 : 80-83

Taxon classification Animalia Hymenoptera Formicidae

Carebara polita (Santschi) Figure 14

Aneleus politus Santschi, 1914a: 79. Syntypes (3 minor workers, CASENT0913517) KENYA: Blue Post Hotel (Thika, ca. 40 km NE of Nairobi), 1520m, i.1912 (Alluaud & Jeannel) [3 syntypes examined].

Oligomyrmex politus (Santschi): Ettershank 1966: 124 (combination).

Carebara polita (Santschi): Fernández 2004: 235 (combination).

Diagnosis.

Antennae with 11 segments. Major worker: Head in full-face view about as long as wide, posterior wider than anterior, posterior head margin with widely V-shaped emargination and small, tooth-like horns at posterolateral corners, propodeum with short, triangular, bluntly rounded spines, dorsum of propodeum nearly straight or very weakly convex, petiole with small, shallowly triangular ventral process, gaster with little, very short and appressed pilosity. Minor worker: Head in full-face view oval with strongly convex sides and deeply concave posterior emargination, face and most of mesosoma smooth and shiny, frontal carinae not extending beyond cephalic midlength, spines elongate-triangular, in dorsal view about as long as distance between them, gaster smooth and shiny and with or without very few standing hairs.

Description of major workers.

Measurements (n=6): HW 1.20-1.74 (1.62), HL 1.17-1.77 (1.59), SL 0.65-0.74 (0.70), MDL 0.68-0.86 (0.80), EL 0.09-0.15 (0.13), WL 1.58-1.80 (1.71), PNH 0.83-1.05 (0.97), PNW 0.93-1.17 (1.07), MNH 1.13-1.35 (1.28), PDH 0.72-0.77 (0.75), PTL 0.65-0.72 (0.68), PPL 0.42-0.48 (0.45), PTH 0.54-0.57 (0.55), PPH 0.47-0.51 (0.48), PTW 0.47-0.58 (0.55), PPW 0.63-0.69 (0.67), PSL 0.29-0.33 (0.31), MFL 1.07-1.16 (1.12), MTL 0.84-0.95 (0.89), CI 97-108 (102), SI 40-54 (44), MDI 45-56 (50), EI 5-9 (8), FI 62-94 (71), PSLI 17-28 (19), LPpI 88-100 (94), DPpI 140-153 (148), PpWI 109-135 (122), PpLI 63-70 (60), PpHI 84-89 (87).

Head about as long as wide (CI 97-108), in full-face view weakly subquadrate, with posteriorly slightly diverging, convex sides, posterior margin usually triangularly emarginate and with small protuberances or horns at posterolateral lobes. Mandibles with five well-developed teeth. Clypeus slightly concave at anteromedian margin, laterally with two carinae. Antennae eleven-segmented, scapes short, reaching slightly beyond midlength of head (SI 40-54). Eyes present, with between ten and sixteen ommatidia (EI 5-9).

In profile, promesonotum roundly convex, much higher than propodeum. Scutum well-developed, scutellum either fused with scutum or vestigial in most specimens, but well-developed in a few major workers. Promesonotal suture present on dorsum, metanotum developed and usually well-separated. Anepisternum and katepisternum large and well separated by a wide groove with some cross-ribs. Dorsal face of propodeum straight and declining posteriorly, propodeal spines comparatively short and stout with rounded tips, declivity of propodeum slightly concave, with lamella reaching from basal edge of spines towards propodeal lobes. Propodeal spiracle close to center of propodeum.

Petiole with moderately short peduncle, in profile ventrally weakly concave with rounded posterior corner, subpetiolar process short and subtriangular to reduced, petiole node in profile high and subrectangular, anteriorly concave, posterior margin vertical and nearly straight, dorsal face nearly straight or weakly convex. Postpetiole in profile lower than petiole (PpHI 84-89), subglobular, almost as long as high (LpPI 88-100), dorsally roundly convex, ventral face much shorter than dorsal face. In dorsal view, petiole wider than long, strongly flattened anteroposteriorly, anterior and posterior faces straight to almost straight, postpetiole weakly hexagonally shaped, on average 1.2 times as wide as petiole (PpWI 109-135), and sides weakly subangulate anteriorly and towards posterior face.

Mandible and head with scattered punctures, except medially on frons. Mandibles smooth and shiny, and laterally weakly striate, clypeus smooth and shiny, with lateral carinae, frons finely longitudinally rugulose, rugulae diverging posteriorly towards posterolateral lobes, at sides of head weaker and more irregular, interspaces weakly to faintly punctate-rugose. Frontal carinae weakly developed, length varying from reaching towards anterior eye level to about midlength of head.

Dorsum of pronotum and scutum variably circularly striate, sometimes only on margins, with center being smooth and shiny, lateral portions of pronotum, anepisternum and katepisternum mostly smooth and shiny to faintly striate. Propodeum longitudinally striate lateroventrally, dorsally and dorsolaterally coarsely sculptured with irregular rugulae, posterior propodeal declivity shagreened or micropunctate. Petiole and postpetiole densely punctate lateroventrally, grading to smooth and shiny on dorsal faces. Gaster smooth and shiny, anteriorly, at articulation with postpetiole, weakly punctate.

In profile, head and body with several short, suberect hairs and scattered short, appressed pilosity. Head in full-face view with two or three relatively coarse suberect hairs present on posterolateral lobes. Scapes and tibiae with abundant appressed and yellow pilosity. Color reddish brown, legs and antennae yellowish or light brown.

Description of minor workers.

Measurements (n=11): HW 0.43-0.54 (0.51), HL 0.50-0.62 (0.57), SL 0.36-0.44 (0.41), MDL 0.25-0.32 (0.30), EL 0.00-0.03 (0.02), WL 0.48-0.76 (0.58), PNH 0.23-0.29 (0.26), PNW 0.26-0.32 (0.29), MNH 0.33-0.42 (0.38), PDH 0.23-0.29 (0.26), PTL 0.23-0.29 (0.25), PPL 0.14-0.18 (0.16), PTH 0.15-0.17 (0.16), PPH 0.10-0.12 (0.11), PTW 0.08-0.12 (0.10), PPW 0.11 -0.15 (0.13), PSL 0.08-0.11 (0.09), MFL 0.38-0.49 (0.45), MTL 0.29-0.38 (0.35), CI 86-91 (88), SI 78-84 (81), MDI 53-62 (59), EI 0-7 (5), FI 78-92 (88), PSLI 16-21 (18), LPpI 136-171 (147), DPpI 75-91 (83), PpWI 119-136 (126), PpLI 58-75 (63), PpHI 61-73 (66).

Head in full-face view longer than wide (CI 86-91), with strongly convex sides, posterior margin of head sharply concave, posterolateral corners angulate to subangulate. Mandibles with four well-defined teeth. Anterior margin of clypeus deeply concave medially, bicarinate and anteriorly divergent, laterally with two small, triangular teeth. Frontal carinae extending towards the cephalic midlength. Antennae with eleven segments, scapes reaching about 6/7 towards posterior margin of head (SI 78-84). Eyes usually present and consisting of one or two ommatidia, rarely no ommatidia visible (EI 0-7).

In profile, promesonotal dorsum smoothly rounded and convex, metanotal groove shallowly impressed. Dorsum of propodeum slightly convex and much shorter than posterior declivity, spines long and lamellate, lamella reaching from spines down toward large propodeal lobes. Propodeal spiracle closer to posterodorsal corner than center of propodeum.

Petiole in profile with moderately long peduncle, ventrally nearly straight, anteroventral corner with a very short to inconspicuous angulate tooth present, petiole node anteriorly slightly concave, posteriorly weakly convex, and dorsal face weakly convex to subangulate anteriorly and posteriorly. Postpetiole in profile convex, on average 1.5 times longer than high (LPpI 136-171), lower than petiole (PpHI 61-73). In dorsal view petiole anteriorly and laterally convex, postpetiole slightly wider than petiole (PpWI 119-136), postpetiole convex and tapering anteriorly, sides subparallel, posteriorly almost straight to faintly convex.

Mandibles, clypeus and face smooth and shiny, with scattered punctures, malar area up to eye level longitudinally striate. Mesosoma mostly smooth and shiny without microsculpture, propodeal lamella, dorsal and posterior propodeal margins weakly alveolate. Petiole weakly alveolate, dorsal face of node, postpetiole and gaster mostly smooth and shiny. Head and body usually without standing hairs and with very little appressed pilosity, in some specimens a few erect, relatively short and stiff hairs with blunt apices present on mesosoma and gaster. Scapes and tibiae with short, appressed pilosity. Color orange to dark brown (in Kibale and Semuliki National Parks, Uganda).

Distribution and biology.

Carebara polita is a widespread species found in Cameroon, Central African Republic, Gabon, Kenya, Tanzania, and Uganda, mainly in rainforest, montane wet forest, and evergreen forest. Carebara polita has been collected at elevations ranging from 110-2045 m. Individuals and nest series were collected in leaf-litter and from soil, using Winkler and pitfall traps.

Comments.

Carebara polita can be easily separated from the other species, because major workers have small protuberances or horns at the posterolateral lobes of head. Minor workers with sides of head strongly convex and head and body mostly smooth and shiny. This species can be confused with Carebara nicotianae , but major workers of Carebara nicotianae do not have horns at the posterolateral lobes, and the mesonotum and propodeum are areolate in Carebara niconianae minor workers, but mostly smooth and shiny in Carebara polita .

Material examined.

CAMEROON: Sud-Ouest, Korup N. P., 6.9 km 317° NW Mundemba, 5.016, 8.864, 110m, rainforest, 19.iv.2000 (B.L. Fisher); CENTRAL AFRICAN REPUBLIC: Prefecture Sangha-Mbaéré, Parc National Dzanga Ndoki, 38.6 km 173° S Lidjombo, 2.36, 16.14397, 350m, rainforest, 21-27.v.2001 (S. Van Noort); GABON: Ogooue-Maritime, Reserve de Faune de la Moukalaba Dougoua, 12.2 km 305° NW Doussala, -2.31667, 10.53333, 110m, rainforest, 24.ii.2000 (B.L. Fisher); Ogooue Maritime, Aire d'Exploit. Rationnelle de Faune des Monts Doudou, 24.5 km 303° WNW Doussala, -2.23283, 10.398, 630m, rainforest, 18.iii.2000 (B.L. Fisher); Woleu Ntem, 31.3 km 108° ESE Minvoul, 2.08, 12.40667, 600m, rainforest, 7.ii.1998, (B.L. Fisher); KENYA: Western, Kakamega Forest, Salazar, 0.32667, 34.87083, 1650m, primary forest habitat, 9.iii.2009 (Marcell Peters); Western, Kakamega Forest, Ivalakale farmland, 0.34556, 34.865, 1650m, farmland, 09.vii.2008 (G. Fischer); Western, Kakamega District, Isecheno, Isecheno Forest Reserve, 0.24, 34.86, 1600m, 31.viii.2001 (W. Okeka); Kikiyu. Esc. Gatamayu, 233 m, montane forest, ii.1999 (Th. Wagner); Mt. Kenya, 0.7km NE Kangaita Forest Sta, 2045m, montane wet forest, 23.i.2000 (R.R. Snelling); TANZANIA: Morogora, Udzungwa Mts. 4.5km W. Chita, 600m, 28.viii.1995 (W.T. Stanley); Morogora, Udzungwa Mts. 3.5km W. 1.7km N Chita, 910m, 7.viii.1995 (W.T. Stanley); UGANDA: Mt. Elgon, Sipi, 1750m, 01.vi.1993 (Cuccodoro & Erne); Kabarole, Kanyawara, Kibale NP, 0.56427485, 30.358759, 1520m, mature wet forest, 4-26.viii.2008 (S. Van Noort); Kabarole, Kanyawara, Kibale NP, 0.56427485, 30.358759, 1510m, evergreen forest, 6-16.viii.2012 (Ant Course 2012); Semuliki NP, 0.83556, 30.15542, 676m, rainforest, 30.vii.-1.viii.2012 (B.L. Fisher et al.).