rhipidura

from The Century Dictionary.

• noun Pl. rhipiduræ (-rē). The posterior pair of pleopods of a crustacean, together with the telson, when these are developed, as in macrurous crustaceans.
• noun For example, the flat shelly plates or swimmerets of the end of a lobster's tail form a rhipidura. See c in cut under pereiopod.
• noun [capitalized] An extensive genus of Muscicapidæ, ranging through the Oriental and Australian regions; the fan-tailed flycatchers. R. flabellifera is an example.