Camponotus reburrus

An unusual species of Camponotus in its lack of major workers.

Identification
The minor worker of Camponotus reburrus is a relatively small (4.4–6.6mm total length) yellowish brown specimen, with a transversely striped yellow and brown gaster, or at least with yellow lateral splotches. The sides of the head are straight and parallel, and the carina on the clypeus is well marked. The antennal scape has numerous erect hairs along the shaft, the hairs on the tibiae are coarse and suberect. Most surfaces are moderately to strongly shining. The female of C. reburrus is a small (total length 6-7mm) hairy specimen, which is shiny dark brown with lighter colored legs. The gaster has lateral yellow splotches. The sides of the head are straight and parallel. The size and abundant erect hairs on the head and scape should separate it from all others in the subgenus Tanaemyrmex. The male of C. reburrus is a small (total length 4.0–5.5mm) dark brown to yellowish brown specimen, with abundant hairs on most surfaces. Other than color and hairiness, it does not seem to possess characteristics which would distinguish it from other small males of Camponotus. The major worker apparently does not exist. (Mackay and Barriga 2012)

Distribution
Known only from northeastern Ecuador.

Distribution based on Regional Taxon Lists
Neotropical Region: Ecuador.

Biology
Three of the winged female-type specimens of Camponotus reburrus were collected in a malaise trap. Others were collected in Cecropia at the edge of secondary growth rainforest or in gaps inside primary growth rainforest. Among the Cecropia species where this species was found are: C. marginalis Cuatrec, C. herthae Diels, and C. membranacea Trecul. The ants were found inside Cecropia internodes and were not aggressive as are Azteca ants. Mullerian bodies and scale insects were found in the internodes where the ant species were living. This species is smaller than Camponotus balzani, but the behavior inside Cecropia nodes is similar: the ants of both species do not attack but run and escape. Camponotus balzani and C. reburrus inhabit Cecropia juvenile and reproductive plants (plants with pistillate or staminate flowers), but most Cecropia species were found more commonly with aggressive colonies of Azteca ants. (Mackay and Barriga 2012)

Nomenclature

 *  reburrus. Camponotus (Tanaemyrmex) reburrus Mackay, W.P., in Mackay & Barriga, 2013: 2, figs. 1-9 (w.q.m.) ECUADOR.

Worker
Minor measurements (mm, n = 4): HL 1.20–1.38, HW 0.90–1.00, SL 1.06–1.14, EL 0.31–0.34, CL 0.36–0.45, CW 0.49–0.53, WL 1.64– 1.84, FFL 0.96–1.08, FFW 0.30-0.31. Indices: CI 72–75, SI 83–88, CLI 108–145, FFI 29–31.

Mandibles with 6 teeth; anterior border of clypeus nearly straight, carina well marked; sides of head straight, parallel, posterior border convex; eyes extend slightly past sides of head; scape extends nearly 1/2 length past posterior lateral corner of head; mesosoma arched throughout, weakly depressed at sutures; dorsopropodeum about twice length of posteropropodeum, face weakly concave, spiracle circular; petiole moderately thickened when viewed in profile, apex rounded when viewed from front. Erect hairs present on head, including surface of clypeus, cheeks, entire length of sides of head, posterior border, between frontal carinae, frons, ventral surface of head, scape with short (0.05 mm) erect and suberect hairs, erect hairs abundant on mesosoma, petiole and gaster, hairs on tibiae abundant and suberect; appressed pubescence sparse, tiny (up to 0.05mm) hairs.

Head and mesosoma coriaceous, gaster transversely striolate, all surfaces moderately to strongly shining.

Ferrugineous red, gaster with yellow lateral splotches ranging to striped brown and yellow.

Queen
measurements (mm, n = 4): HL 1.66–1.74,HW1.22–1.26, SL 1.32–1.40, EL 0.51–0.54, CL 0.56–0.58, CW 0.58, WL 2.62–2.68, FFL 1.44, FFW 0.38-0.39. Indices: CI 72–74, SI 79–81, CLI 100–102, FFI 26-27.

Clypeus with carina poorly developed; anterior clypeal border concave, medial portion meeting lateral portion in rounded angle; frontal carinae closely placed; eyes large, extending past sides of head; scape short, extending past posterior lateral corner of head by 1.5 funicular segments; head elongate, rectangular with nearly parallel sides; posterior margin convex, rounded; mesosoma elongate; pronotum lengthened and lowered in profile; metanotal suture deep, propodeum lower than remainder of mesosoma, rounded; petiole thick in profile.

Erect hairs abundant, about 20 scattered over surface of clypeus, 5-6 on cheek, 5 or more on malar area, erect hairs on posterior margin and posterior lateral corner of head, scape with two distinct types of hairs, erect (or nearly erect) longer (0.13mm) hairs, and not very abundant (fewer than 10, excluding similar hairs at apex), and suberect short (>0.08mm) abundant (about 100) hairs, pronotum with long (0.4mm) erect hairs along posterior border, erect hairs scattered on dorsum of remainder of mesosoma, petiole and gaster, femora with several nearly erect hairs, tibiae with numerous hairs that are mostly suberect; appressed pubescence sparse, short on head (0.02 mm), longer on gaster (0.06 mm).

Sculpture finely coriaceous, but strongly shining.

Color predominantly dark brown, legs lighter brown, coxae, trochanters and base of tibiae yellow, gaster with lateral yellow blotches on each tergum.

Male
measurements (mm, n = 4): HL 0.98–1.04,HW0.84–0.86, SL 0.92–0.96, EL 0.39-0.40, CL 0.29-0.30, CW 0.34–0.36, WL 2.06–2.12, FFL 1.32–1.36, FFW 0.24-0.25. Indices: CI 83–86, SI 92–94, CLI 117–121, FFI 18.

Mandible without teeth, except apical angle; anterior border of clypeus broadly convex, clypeal carina poorly defined, but present; sides of head anterior to eyes concave, nearly parallel, posterior border of head broadly rounded, concave between ocelli; scape extending approximately 1/2 length past posterior lateral corner of head; eye large, occupying approximately 1/2 length of side of head; ocelli well developed; propodeal spiracle oval shaped; petiole thick when viewed in profile, apex slightly flat but convex as seen from front.

Erect and suberect hairs present on mandibles, clypeus, dorsum and ventral surfaces of head; sides of head, posterior border of head, dorsum of mesosoma, legs, petiole, and all surfaces of gaster; appressed hairs sparse few present on head, mesosoma, and gaster.

Dorsum of head coriaceous, mesosoma coriaceous but somewhat glossy, especially scutellum, side of pronotum, mesopleuron, gaster transversely striolate, moderately shining.

Pale medium brown, mandibles, cheeks, antennae, parts of scutum, legs yellowish brown.

Type Material
Holotype Female. Ecuador, Napo, Sucumb´ıos, Sacha Lodge, 0.5 S 76.5 W, 290 m, 22-ii-1994, P. Hibbs (Los Angeles County Museum of Natural History); Paratype females (3)same data as holotype, 4-iii-1994, 20,30-ix-1994, 10,21-xi-1994 (Los Angeles County Museum of Natural History,Museo de Zoolog´ıa, Pontificia Universidad Catolica del Ecuador); additional paratypes including Orellana, Yasuni Research Station, 0◦40 S 76◦ 23 W, 200 m, 17-i-2009, C. Sagers and J. Trager numbers 2009-502, 2009-506, 2009-510, 2009-515 (26 workers, 1 dealate female, 4 alate females,4 males), same locality, 19-i-2009, P. Barriga and G. Alvia numbers 2009-021, 2009-028, 2009-030, 2009-031, 2009-037 (58 workers, 3 females, 18 males). The female was selected as the holotype as the minor workers, and males of Camponotus spp. are often indistinguishable. Paratypes will be distributed to major South American, North American, and European museums, including the California Academy of Sciences, Collection of William and Emma Mackay, University of Texas, El Paso, Ernst-Moritz-Arndt-Universitat, Greifswald, Germany, Los Angeles County Museum of Natural History, Museum of Comparative Zoology, Harvard University, Museo de Historia Natural, Universidad Nacional de Colombia, Museo de Zoolog´ıa, Pontificia Universidad Cat ´ olica del Ecuador, Museu de Zoolog´ıa da Universidade de S˜ao Paulo, Brasil,Mus´eum d’Histore naturelle, Gen´eve, Switzerland and the Naturhistorisches Museum Wien, Burgring, Austria.

Etymology
From Latin, reburrus,meaning one with bristling hair, referring to the hairs on the head.

References based on Global Ant Biodiversity Informatics

 * Mackay W., and P. A. Barriga. 2013. A new species of Neotropical carpenter ant in the genus Camponotus (Hymenoptera: Formicidae), apparently without major workers. Psyche 2012, Article ID 382938