Tenebroides

Adults are elongate, somewhat flattened beetles with a prognathous head and prominent mandibles. The body form is characteristic of Trogossitidae, with elytra that may be striate or smooth depending on species. Larvae are elongate and somewhat flattened with well-developed legs, differing from the often legless or reduced-legged larvae of many other beetle families. Specific identification to species level requires examination of genitalia and other microscopic characters.

Habitat varies by species: T. mauritanicus occurs in stored grain facilities, flour factories, and warehouses; T. collaris and related species inhabit bark, decaying wood, and forest litter. T. mauritanicus overwinters in wood boards and sawdust within storage structures.

The genus has a broad distribution. T. mauritanicus originated in Africa and has spread to high temperate and cold zones worldwide, including China (Fujian Province) and Turkey (Bursa Province). T. collaris occurs in North America with documented records from Montana, USA. Distribution records from GBIF indicate presence in Denmark, Norway, and Sweden.

Adult T. mauritanicus emerge beginning of June under natural conditions in Turkey. Overwintering occurs as adults (primarily) or larvae. Activity patterns in storage facilities are continuous year-round due to controlled conditions.

T. mauritanicus feeds on grain, soybean, and corn in storage. Larvae feed on these stored products and produce peeling and feces that contaminate food. Diet of other Tenebroides species in natural habitats is poorly documented but likely includes fungi, other insects, and decaying organic matter based on family-level patterns.

T. mauritanicus: eggs hatch in approximately 4 days; larvae pass through 5 instars with mean development of 171 days on grain; pupal stage averages 12 days; preoviposition period averages 15 days; total development averages 206 days (range 67–342 days) for one generation. Overwintering as adults or larvae. Sex ratio female:male 2:1. Other species: life cycle details not documented.

T. mauritanicus adults and larvae both occur in storage environments. Larvae produce peeling and fecal contamination of stored products. Adults are attracted to sex pheromones, which has been used for collection and monitoring.

T. mauritanicus is an important storage pest with significant destructive power, causing food contamination and economic damage in grain storage systems. Native forest-dwelling species likely function as predators, fungivores, or saprophages in dead wood and bark communities, though specific ecological roles are undocumented.

T. mauritanicus (cadelle) is a significant stored product pest of international importance, infesting grain, flour, and other stored commodities. It causes direct damage through feeding and indirect damage through contamination with frass and cast skins. The species is subject to pest management in food storage and processing facilities. Other Tenebroides species have no documented economic impact.

• ByturusPhylogenetically closest to T. mauritanicus based on mitochondrial genome analysis; both belong to Cleroidea but in different families (Trogossitidae vs. Byturidae)
• Other TrogossitidaeShare bark-gnawing habits and elongate body form; require genitalia examination for definitive separation

• Coleoptera
• Trogossitidae
• stored product pest
• grain pest
• bark beetle
• cadelle

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Studies on the Biology and Distribution of Cadelle, Tenebroides mauritanicus (L.) (Coleoptera: Trogossitidae) in Bursa, Turkey
• The Bark-Gnawing Beetles of Montana, USA (Coleoptera: Trogossitidae, Peltidae, and Lophocateridae), Including New Substantial Distributional Records for Tenebroides collaris (Sturm)
• The complete mitochondrial genome of Tenebroides mauritanicus Linnaeus, 1758 (Coleoptera: Trogossitidae).