Ectobius is a genus of non-cosmopolitancockroaches once thought native to the Old World and described by James Francis Stephens in 1835, belonging to the family Ectobiidae, subfamily Ectobiinae. The oldest known member of the genus, Ectobius antiquus, was described from the Upper Cretaceous strata of the Nenjiang Formation (China). The discovery of 4 Ectobius cockroaches in Colorado dating to 49 million years ago suggests that members of the genus were present in North America in the past before their reintroduction by humans. This genus has been subject to a number of revisions.
Description
Ectobius species – Nymph
The adult 'cockroaches' reach 6–12 millimetres (0.24–0.47in) of length, the basic coloration of their body is mostly brown or yellowish, with a clearer margin.
The females are usually bigger than the males and have shorter wings, while in the males wings cover at least the whole abdomen.
Distribution
Species of this genus are mainly present in most of Europe, Africa, in eastern Palearctic realm and the Near East. The "lesser cockroach" (i.e. as found in Britain), previously placed here, is now in the genus Capraiellus.
The genus was long absent from the North American continent until recent re-introductions of some cool-adapted species in the Canadian Maritimes and North Eastern, US.
↑Hinkelman, J.; Li, L.-W. (2026). "Cretaceous cockroach assemblage from the Nenjiang Formation, China expands the fossil record of modern ecosystems". Palaeoworld 201204. doi:10.1016/j.palwor.2026.201204.
↑Bohn, H. 1989: Revision of the sylvestris group of Ectobius Stephens in Europe (Blattaria: Blattellidae). Entomologica Scandinavica, 20: 317–342.
12Bohn (2013) In Bohn, Beccaloni, Dorow & Pfeifer. Another species of European Ectobiinae travelling north – the new genus Planuncus and its relatives (Insecta: Blattodea: Ectobiinae). Arthropod Systematics & Phylogeny71(3): 147.
