Formicinae, Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
Additional images: minor worker, dorsal view of mesosoma (reduced, original).
Mexico to Colombia, ?Brazil: RJ. Costa Rica: possibly throughout the country but seems to have a somewhat patchy distribution.
Minor worker: Propodeum lacking spines or tubercles of any kind; propodeum somewhat box-like, dorsal and lateral faces flat or nearly flat and meeting at an approximate right angle; dorsal face of propodeum subrectangular; pubescence on first gastral tergite dilute, appressed to suberect, not obscuring integument; color dark brown to black; size very small; propodeal suture deeply impressed; dorsal and lateral faces of propodeum meeting at relatively sharp angle; mesonotal dorsum longitudinally striatopunctate.
I have many records of this species from around Monteverde in the Cordillera de Tilaran. I also have records from the Cordillera de Guanacaste (Cerro Cacao, Maritza, and Pitilla), Carara, and Manuel Antonio. I collected it in Parque Nacional in the middle of the capital city, San Jose. On the Atlantic slope, I have records from Hitoy Cerere and La Selva Biological Station. In spite of abundant collecting, I never encountered the species in Corcovado National Park. At La Selva, it seems to be very rare. Henry Hespenheide collected it once in 1988 and again in 1992. The latter collection was from vegetation reachable from the suspension footbridge across the Rio Puerto Viejo. The species has not been collected again, in spite of extensive inventory work at La Selva.
This is a tiny Camponotus species that usually lives in very open habitats. It often nests in very narrow-guage dead herb and vine stems, and I usually encounter them along weedy road margins or pasture edges. I have found nests in dead stems down to 3mm outside diameter, in various dead branches in low scrubby vegetation, in dead herb stalks along roadsides, in dead thorns of Acacia ruddiae, and in dead nodes of Cordia alliodora. A cluster of dead composit stalks contained a nest with only workers in a section of 12mm diameter stem, and workers and brood in a nearby hollow stem gall. This suggests they can be polydomous. I have often found single queens in nests, but in one case I found four dealate queens in a nest collection, so it appears they can be monogynous or polygynous.
Camponotus striatus has a strong foetid odor, like army ants. When nests are disturbed and workers are collected into alcohol the odor is easily detected. I have not noticed a foetid odor in any other species of Camponotus. These "ecitonine" odors occur sporadically in other ants (e.g. Pheidole fallax, various other Pheidole species). It has been hypothesized that these odors might be an evolved defense against army ants, and that the odors somehow repel army ants or disrupt their raiding behavior. Another possibility is that it repels attacks by various other ants that have evolved to flee from ecitionine odors.
Smith, F. 1862. Descriptions of new species of aculeate Hymenoptera, collected at Panama by R. W. Stretch, Esq., with a list of described species, and the various localities where they have previously occurred. Trans. Entomol. Soc. Lond. (3)1:29-44.
John T. Longino, The Evergreen State College, Olympia WA 98505 USA.email@example.com
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