Decapod anatomy Decapod anatomy The decapod crustacean, such as a crab, lobster, shrimp or prawn, is made up of 20 body segments grouped into two main body parts, the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various groups these may be reduced or missing. They are, from head to tail: The head also bears the (usually stalked) compound eyes. The distal portion of a mandible or maxilla which has a sensory function is known as a palp. Maxillipeds are appendages modified to function as mouthparts. Particularly in the less advanced decapods, these can be
Nephilengys upon by the spider-eating jumping spider "Portia". At least some species shake their bodies vigorously when touched. Nephilengys Nephilengys is a genus of tropical spiders of the family Araneidae, consisting of two currently described species. (The genus was formerly placed in the Nephilidae and Tetragnathidae.) The genus "Nephilingis" has been split off from this genus. Both genera have been called hermit spiders from the habit staying in their retreats during the day; the name eunuch spiders has been used for "Nephilengys" alone. Males may sever parts of their palpal bulbs after copulation. Females are from 10 mm to 28 mm