This Armored Cockroach (Catara rugosicollis) got to be the coolest cockroach i've seen.... it is also the smelliest! I use my hand to stop it from running away and it spray a smelly chemical on my hand. Even after some intensive washing, the smell still stay with me for 3 days! Taken at night in Singapore forest. Size 1.5 inches.
Quote from en.wikipedia.org/wiki/Cockroac…
Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitats. About four species are well known as pests.
The name "cockroach" comes from the Spanish word for cockroach, cucaracha, transformed by English folk etymology into "cock" and "roach". The scientific name derives from the Latinized Greek name for the insect (Doric Greek: βλάττα, blátta; Ionic and Attic Greek: βλάττη, bláttē).
Mantodea (praying mantises), Isoptera (termites), and Blattaria are usually combined by entomologists into a higher group called Dictyoptera. However recent genetic evidence strongly suggests that termites evolved directly from true cockroaches, and many authors now place them as an "epifamily" of cockroaches.
Historically, the name Blattaria has been used largely interchangeably with the name Blattodea, and this name is used for the order by the current world catalogue, the Blattodea Species File Online. Another name, Blattoptera has come into use for this same paraphyletic group. These earliest cockroach-like fossils ("blattopterans" or "roachids") are from the Carboniferous period 354–295 million years ago. However, these fossils differ from modern cockroaches in having long external ovipositors and are the ancestors of mantises, as well as modern roaches. The first fossils of modern cockroaches with internal ovipositors appeared in the early Cretaceous.
Cockroaches live in a wide range of environments around the world. Pest species adapt readily to a variety of environments, but prefer warm conditions found within buildings. Many tropical species prefer even warmer environments and do not fare well in the average household.
Cockroaches are mainly nocturnal and will run away when exposed to light. A peculiar exception is the Asian cockroach, which is attracted to light.
The spines on the legs were earlier considered to be sensory, but observations of their locomotion on sand and wire meshes have demonstrated they help in locomotion on difficult terrain. The structures have been used as inspiration for robotic legs.
Cockroaches leave chemical trails in their feces, as well as emitting airborne pheromones for swarming and mating. These chemical trails transmit bacteria onto surfaces. Other cockroaches will follow these trails to discover sources of food and water, and also discover where other cockroaches are hiding. Thus, cockroaches can exhibit emergent behavior, in which group or swarm behavior emerges from a simple set of individual interactions.
Daily rhythms may also be regulated by a complex set of hormonal controls of which only a small subset have been understood. In 2005, the role of one of these proteins, pigment dispersing factor (PDF), was isolated and found to be a key mediator in the circadian rhythms of the cockroach.