Dicerca tenebrica is a species of metallic wood-boring beetle (family Buprestidae), commonly known as the flatheaded poplar borer or flatheaded wood borer. It was first described by William Kirby in 1837. It is a recognized species with established taxonomic and entomological documentation.
Taxonomy
- Kingdom: Animalia
- Phylum: Arthropoda
- Class: Insecta
- Order: Coleoptera
- Suborder: Polyphaga
- Infraorder: Elateriformia
- Family: Buprestidae (jewel beetles / metallic wood-boring beetles)
- Subfamily: Chrysochroinae
- Tribe: Dicercini
- Genus: Dicerca
- Species: D. tenebrica (Kirby, 1837)
Recorded synonyms include Buprestis tenebrica, Stenuris tenebrica, and Dicerca prolongata.
Description
The species is a medium-sized buprestid with a rigid, elongated, moderately convex and broadly flattened body. The upper surface color is variable, ranging from brass-colored to black, sometimes with a bluish tint, with metallic reflections and pale or white speckling; the underside is described as coppery and iridescent. The head is flattened — the feature reflected in the common name — and slightly impressed in the middle. The pronotum is wider than long, with coarsely punctate sculpturing and a median channel. Males measure roughly 15.0–21.5 mm in length and 4.8–7.2 mm in width; females are somewhat larger, approximately 14.5–26.0 mm in length and 4.5–9.0 mm in width. Females of this species are distinguished within the genus by a reduced or absent middle tooth.
Distribution
The species is recorded from Canada and the northern, southern, and northeastern United States. Documented occurrences include eastern populations from Nova Scotia south to Massachusetts and west to southern Ontario and Minnesota, and western populations from Alaska south to New Mexico and east to Manitoba and Nebraska.
Ecology and Behavior
Adults are active from approximately March to November and are described as sun-loving, often observed on logs, trunks, branches, or foliage of host trees. Adults feed on leaves of trees in the genus Populus (poplars and aspens), including balsam poplar, bigtooth aspen, and quaking aspen. In Alberta, records also associate the species with lodgepole pine, jack pine, and white spruce. Eggs are laid in wounds, cracks, or crevices in the rough bark of sun-exposed branches and branch stubs. Larvae bore into the sapwood and heartwood of recently dead wood or dead parts of living trees (flatheaded borer habit). Development is presumed to take several years, though detailed development data for North American populations are described as unknown. Adults are reported to hibernate under loose bark.
Conservation Status
The species is generally treated as common in suitable habitat, and is described as possibly the most frequently encountered Dicerca species in aspen forests. It is not listed on the IUCN Red List, and NatureServe status is recorded as unranked (NNR); it is not listed in Minnesota.
