Camponotus variegatus is a large yellowish brown species most easily recognized by the posterior margins of gastral tergites which are marked by subtriangular, medium brown infuscations that contrast sharply with the anterior portions of the tergites. The species is likely part of a taxonomically unresolved complex native to Southeast Asia (Wilson & Taylor, 1967), where many of the infraspecific taxa were described from (Bolton et al., 2006). It has established introduced populations across all of Hawaii’s main islands, and some of the Northwest Hawaiian Islands. In Hawaii it is considered a pest species, and is found nesting in and around houses (Forel, 1899; Reimer et al., 1990).
The first record of the ants in Hawaii was published by Forel (1899)under the unavailable quadrinomial Camponotus maculatus r. mitis var. hawaiensis. The first available name given to these ants was Camponotus variegatus subsp. hawaiensis Emery. Wilson and Taylor (1967), realizing that the Hawaii population was likely recently derived from the introduction of an Asian species, synonymized C. variegatus subsp. hawaiensis with Camponotus variegatus (Smith, F.).
Reimer (1994)reported that Camponotus variegatus has only been collected in dry and mesic areas below 500 m where it is quite common, but qualifies the known distribution by noting that its nocturnal activity reduces the chances of detection during daytime surveys (the species is the only exclusively nocturnal ant species in Hawaii). Wheeler’s (1934b)collection from Hawaii at 1300 m suggests the species may have been more widespread at higher elevations prior to the introduction of other ant species.
In Hawaii it is considered a pest species, and is found nesting in and around houses
Diagnosis of worker among Antkey species. Worker caste polymorphic. Antenna 12-segmented. Antennal club indistinct. Antennal scape length less than 1.5x head length. Eyes medium to large (greater than 6 facets); lacking distinct ocelli. Antennal sockets and posterior clypeal margin separated by a distance equal to or greater than the minimum width of antennal scape. Head length longer than head width. Propodeum and petiolar node both lacking a pair of short teeth. Propodeum not angulate and lacking a distinct dorsal and posterior face; also lacking posteriorly projecting protrusion. Metapleuron lacking a distinct gland orifice. Waist 1-segmented. Petiole upright and not appearing flattened. Gaster armed with acidopore; variegated with dark transverse bands running near posterior margins of tergites that contrast with the paler yellow of the rest of gaster and body. Distinct constriction not visible between abdominal segments 3+4. Hairs not long thick and produced in pairs. Erect hairs relatively sparse on head and mesosoma.
Camponotus variegatus is diagnosed from other members of the genus introduced or commonly intercepted in the United States by the following characters: (1) metanotal groove not distinctly impressed (versus C. sexguttatus); ); (2) long erect hairs sparse on head and mesosoma (versus abundant in C. atriceps and C. planatus); (3) propodeum not angulate and lacking a distinct dorsal and posterior face (versus C. rectangularis); (4) gaster variegated with dark transverse bands running near posterior margins of tergites that contrast with the paler yellow of the rest of gaster and body (versus with distinct whitish spots (some C. sexguttatus) or concolorous (all others).
Native range. SE Asia.
Introduced range. Hawaii (all main islands, and some of the Northwest Hawaiian Islands).