Formicinae, Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
Additional images: major worker, lateral view of head (reduced, original), scape (reduced, original).
Honduras to Brazil. Costa Rica: throughout country to about 1200m elevation.
Minor worker: propodeum very narrow, in cross section tectiform (tent-like, like an inverted "V"), without a distinct angle separating lateral and dorsal faces; WL of typical minor workers around 1.7mm; in lateral profile dorsum of mesonotum, dorsal and posterior faces of propodeum flat, meeting at obtuse angles; body concolorous yellow; in lateral view, clypeus convex or weakly angulate.
Major worker: head moderately phragmotic, anterior truncation not sharply defined, clypeus convex.
Similar species: curviscapus.
This species is one of the most common Camponotus in Costa Rica. Nests generally occur in highly insolated areas: canopy of mature wet forest, open secondgrowth habitats, dry forest, scrubby roadside vegetation, and agricultural areas. In lowland sites it can occur in both mature and second growth forest, but at higher elevations is increasingly restricted to open or disturbed habitats.
The foraging behavior of this species is unknown. I have many nest collections but relatively few collections of foraging minor workers. It may be that foraging is mainly nocturnal, which would explain the paucity of foragers in my collections (I spend much more time collecting during the day than at night). Another possibility is that the foraging rate is generally low.
The nests are small and occur in narrow-guage dead plant stems, usually 5-10mm outside diameter. The majors have elongate subcylindrical heads (although not as sharply plug-like as C. curviscapus and subgenus Colobopsis). I have never observed the behavior of major workers in nests, so I do not know whether major workers use their heads to block the nest entrance. Camponotus claviscapus appear to have irregular, cryptic nest entrances. There is no discrete, circular entrance (species with more distinctly phragmotic heads have circular nest entrances that are exactly the size and shape of the major head, which is used to plug the entrance).
I have occasionally collected lone founding queens in small dead stems, suggesting monogynous claustral founding.
Forel, A. 1899. Biologia Centrali-Americana; or, contributions to the knowledge of the fauna and flora of Mexico and Central America. Insecta. Hymenoptera. 3 (Formicidae). London. 169 pp.
John T. Longino, The Evergreen State College, Olympia WA 98505 USA.email@example.com
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