Raphe see rhaphe

raphide n. [Gr. rhaphidos, needle] (PORIF: Desmospongia) A

thin diactinal microsclere lacking ornamentation.

raptorial a. [L. raptor, robber] Fitted for grasping prey.

raptorial claw 1. (ARTHRO: Crustacea) The toothed dactyl curved backward on the propodus. 2. (ARTHRO: Insecta) In Mantids, the spinose tibiae and femur that produce the hook.

rasorial a. [L. rasor, scraper] Adapted for scratching.

rasp n. [OF. rasper, to scrape] 1. (ARTHRO: Crustacea) One or more rows of chitinous plates or scales on the pereopodal or uropodal surface segments. 2. (ARTHRO: Insecta) A roughened surface for the production of sound by friction. see strigulating organs.

Rassenkreis n. [Ger. Rasse, race; Kreis, circle] Polytypic species; rheogameon. see circular overlap.

rastellum n. [L. dim. rastrum, rake] (ARTHRO: Chelicerata) In Arachnida, a structure on the chelicera bearing numerous tooth-like projections, stout and rigid spines, or seta; the paturon.

rastellus n. [L. dim. rastrum, rake] (ARTHRO: Chelicerata) In Arachnida, the teethlike projections on the chelicera borne by the rastellum or paturon.

raster n.; pl. rastri [L. rastrum, rake] (ARTHRO: Insecta) A complex of bare areas, hairs and spines on the ventral surface of the last abdominal segment, in front of the anus in Scarabaeoidea; comprised of septula, palidium, teges, tegillum in some groups, and campus in Coleoptera.

rastrate a. [L. rastrum, rake] Having longitudinal scratches over the surface.

rataria larva (CNID: Hydrozoa) In some Siphonophora, free-swimming larva, hourglass in shape, with an anterior disc collar; develops from the conarium larva.

ratite a. [L. ratis, raft] Lacking a keel; a smooth ventral somite; lacking ridges or raised lines. see carinate.

rat-king cercariae (rattenkonig) (PLATY: Trematoda) Marine cercariae that occur in masses, with the tail tips attached to a protoplasmic mass.

rat-tailed larva/maggots (ARTHRO: Insecta) In Diptera, Syr-

phidae larva having a long flexible respiratory tube extending from the end of the body.

ray n. [L. radius, ray] 1. One of a number of fine lines radiating from a center. 2. Each arm of the triradiate lumen of nematodes and other pseudocoelomates. 3. A division of a radiate animal.

reafference n. [L. re, again; afferre, to bring] Sensory impulses caused by an animal's movements relative to the environment. see afference.

reborded a. [F. rebord, rim] (ARTHRO: Chelicerata) In Acarina, pertaining to the distal thickened and strengthened end of the labium.

recapitulation theory The theory that ontogeny recapitulates phylogeny.

recent n. [L. recens, new] Taxa still in existence.

receptacle n. [L. recipere, to receive] Any organ that receives and stores; acting as a repository.

receptaculum n. [L. recipere, to receive] A receptacle.

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