Brown cockroach

Brown cockroach
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Blattodea
Family:	Blattidae
Genus:	Validiblatta
Species:	V. brunnea
Binomial name
Validiblatta brunnea {Burmeister, 1838)
Synonyms
Periplaneta brunneaBurmeister, 1838 [1] Periplaneta concolorWalker, 1868 Periplaneta patensWalker, 1868 Periplaneta truncataKrauss, 1892 Periplaneta ignotaShaw, 1925

The brown cockroach (Validiblatta brunnea), synonym Periplaneta brunnea, ^[1] is a species of cockroach in the family Blattidae. It is probably originally native to Germany, but today it has a circumtropical distribution, having been widely introduced. ^[2] In cooler climates it can only survive indoors, ^[3] and it is considered a household pest. ^[2]

Appearance

This cockroach is similar in appearance to the American cockroach (Periplaneta americana), but darker in color and with thicker, wider, triangular cerci. This species is a reddish-brown color and has fully developed wings. ^[3] It reaches up to 4 centimeters in length. ^[2]

Ecology

Brown cockroaches are omnivores ^[3] and give off unpleasant smells when threatened or touched. Males are usually smaller than their female counterparts. They are social insects and like to be in large groups, resting in warm, moist, dark areas. This species prefers indoor areas and are often known as the pests that linger around homes. This contrasts with the habits of American cockroaches, which prefer to live in outdoor areas like the sewers on the streets, and only come into homes when there are changes in the weather climate or when food is limited.

Reproduction

Brown cockroaches produce an ootheca about 1.2 to 1.6 centimeters long, containing about 24 eggs on average. ^[4] It is longer compared to the American cockroach, one ootheca of which contains around 28 eggs on average.

Distribution

This species has a cosmopolitan distribution, present on all continents except Antarctica.

References

1. Luo, X.; Deng, W.; Han, W.; Lo, N.; Cai, J.; Che, Y. & Wang, Z. (2025). "Revision of the cockroach subfamily Blattinae based on morphological and molecular analyses". Systematic Entomology: 1–19. doi:10.1111/syen.12680.
2. Periplaneta brunnea, Brown Cockroach. Cook Islands Biodiversity Database. The Cook Islands Natural Heritage Trust. 2007.
3. Periplaneta brunnea (Burmeister, 1838). Archived November 15, 2012, at the Wayback Machine Orthopteroids of the British Isles Recording Scheme.
4. Periplaneta brunnea Burmeister, 1838. PaDIL.

External links

• Black and white photographs of top view of P. brunnea male and female specimens, from Smithsonian Miscellaneous Collections.
• Drawings of body parts of male P. brunnea; plate VII, figures 12-16 show detail of the pronotum, end of abdomen with cerci, genital process, subgenital plate, and supra-anal plate with cerci. From a 1917 article by Morgan Hebard, with a key to the figures on page 280.
  • Hebard, Morgan (1917). "The Blattidae of North America north of the Mexican boundary". Memoirs of the American Entomological Society. 2: 1–284.