Decapod anatomy are referred to as the "gonopods". At the end of the pleon is the tail fan, comprising a pair of biramous uropods and the telson, which bears the anus. Together, they are used for steering while swimming, and in the caridoid escape reaction. In crabs and some other carcinised decapods, the abdomen is folded under the cephalothorax. 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
Saw-billed hermit to the typical hummingbirds, Trochilinae (Hinkelmann, 1999). This, coupled with the considerable number of autapomorphies such as the unusual bill, suggest it is the most primitive species of the hermit lineage; a situation paralleled by the equally unusual tooth-billed hummingbird in the Trochilinae. Saw-billed hermit The saw-billed hermit ("Ramphodon naevius") is a hummingbird from southeastern Brazil, the only member of the genus Ramphodon. It is around 14–16 cm long and is one of the heaviest of the hermits; its straight bill has a hooked tip. It lives in humid forests, where it aggressively defends feeding routes ("trap-lines") from individuals of