Camponotus depressus

Camponotus depressus selectively nests in dead bamboo occurring from Amazonia, Brazil south to Paraguay (Davidson et al., 2006). This ant is not an obligate bamboo nester. De Oliveira et al. (2015) found a colony opportunistically nesting in a Cecropia saxatilis tree (southwest Bahia, Brazil).

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Paraguay.

Biology
C. depressus may be tied to dead bamboo because it provides superior nest sites, or by nutritional dependency on prodigious wound exudates produced at sites of insect damage to growing culm tips (Davidson et al., 2006). Such strict reliance on nests in dead bamboo has not been reported in Asian bamboo ants.

Leite et al. (2013) studied the foraging behavior of Celeus obrieni (Kaempfer's Woodpecker), a bamboo specialists that feeds on ants. This field study was conducted in central-western Brazil on the plains of the Araguiai River from 2008-2010. The research focused on foraging by C. obrieni on Guadua paniculata, a large bamboo species, in cerradão habitat. Celeus obrieni are known to forage and breed in patches of G. paniculata. Ants use the hollow stems of the bamboo as a nesting resource.

Leite et al. found the woodpeckers, in comparison with standardized foraging observations on other plants around these same sites, concentrated their foraging on bamboo. A sample of stems (n = 900) that were not visited by the woodpecker showed ~40% contained ant nests. Thirteen ant species were found, with three being common (76% of all nests): Azteca fasciata, Camponotus atriceps, and Camponotus depressus. Most nests for these were located 2-4 m from the ground. Dead stems (59%) contained more nests than live stems. A second set of bamboo stem samples, those foraged on and drilled into by C. obrieni, were also inspected. Drilling was concentrated at the same height where the majority of ant nests were found in the unforaged-stem samples. Despite the much larger proportion of live stems within each stand, more dead (62%) than live stems were drilled. Fifty-nine percent of the drilled stems contained ant colonies. Nests of Camponotus depressus were the most common, Azteca fasciata less frequent, and Camponotus atriceps found in only four of the drilled stems.

Nomenclature

 *  depressus. Camponotus depressus Mayr, 1866a: 487, pl., fig. 1 (w.) BRAZIL. Menozzi, 1925b: 371 (q.). Combination in C. (Myrmomalis): Forel, 1914a: 263.