placoid


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placoid

 [plak´oid]
platelike or plaquelike.

placoid

(plăk′oid)
adj.
Platelike.

placoid

Plate-like.

placoid

or

denticle

the dermal denticles of cartilaginous fish. Placoids are tooth-like structures of enamel, covered with dentine. Compare COSMOID, GANOID.

placoid

platelike or plaquelike.
References in periodicals archive ?
Removed or damaged placoid scales of nurse (Ginglymostoma cirratum) and leopard (Triakis semifasciata) sharks have been shown to be rapidly replaced (Reif 1978), possibly because of their vital function in protecting the fish against the external environment (Quilhac et al.
The closely-placed scutellar placoid sensilla, and the shape of the stigmal vein, strongly suggest it is a member of the Encarsia strenua (Silvestri) group, all species of which are parasitoids of Aleyrodidae.
5 mm) with scattered, small setae (1= 10 [micro]m); placoid sensilla close to the insertion of the mandibles.
Martin exactly matched the original description of Murray (1907); in the absence of eggs the species can be distinguished from other Macrobiotus species with similar placoids and claws by the presence of conspicuous orange to reddish brown inclusions.
Paratypes and other material examined: 6 paratypes and 7 eggs, same data as holotype (accession numbers 9340, 9343, 9346, 9349); 2 additional eggs, 109 additional specimens, same collection data as holotype; 1 paratype and 1 egg, same collection data as holotype, deposited in the Natal Museum, Pietermaritzburg, South Africa (accession numbers 9347, 9348); 1 cluster of three connected eggs found; 1 embryonated egg found with buccal apparatus and placoids.