A complete guide to cockroach species

There are more than 6,000 species of cockroaches, but the most common are the American, German, brown-banded, and Oriental cockroach. The American cockroach is about 30 to 50 mm long, with the largest reaching two inches; it is a common large indoor roach found mainly in tropical and subtropical regions such as Guangdong, Guangxi, Hainan, and Fujian.

The German cockroach is small, reproduces in large numbers, and is very widespread. The brown-banded cockroach resembles the German cockroach but is slightly smaller. The Oriental cockroach is relatively large at about 25 to 30 mm, glossy, and black or dark brown in color.