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A simple, epithelial sense organ composed of one cell or of a few cells.



in invertebrates, a simple cutaneous organ of touch, taste, or chemical sense. The external part of a sensillum is formed by the cells of the integuments and is represented by a hair (tactile sensillum) or a slender cuticular plate, a peg, or a cone lodged in a depression (olfactory and gustatory sensilla). At the sensillum’s base there are one or more sensory nerve cells connected to the central nervous system by nerve fibers. In arthropods, tactile sensilla (hairs) are usually found on all parts of the body. Olfactory sensilla are especially numerous on antennae; for example, a worker bee has as many as 6,000 sensilla on each antenna. Gustatory sensilla are found on mouthparts. Often individual sensilla unite to form more complex sense organs.

References in periodicals archive ?
The labium consisted of 2 labial palps with a sensillum styloconicum at the apex, a sensillum chaeticum in the center (Fig.
Although the type 1 sensillum morphotype is confined to the medial flagellum and is present in a very low number (18-20), it appears, in size and distribution, to be unique to P.
This infraorder represents a monophyletic taxon, which is supported by one syn(apomorphy) character (27-1; absence of the elongated plate sensillum).
18) with scape 3.0-3.4x as long as wide, with cross-ridges, a little shorter than clava; pedicel much longer than F1 (the shortest funicle segment); F2, F6, and often F4 the longest funicle segments (F6 sometimes slightly longer than F2 and F4), F3 and F5 slightly shorter (F5 sometimes almost as long as F4); F1-F3 and F5 without longitudinal sensilla, F4 with 1 longitudinal sensillum, and F6 with 2 such sensilla; clava 2.7-2.8x as long as wide (in lateral view), with 5 longitudinal sensilla.
While the B event appears to be separate from A1 and A2, this does not preclude the possibility that it could result from the coupling of at least two other events within the peg sensillum. Alternatively, it could be a summation of two active conductances within the same cell.
albopictus two coeloconic sensillum are protruding from the tip of distal flagellum as a tubular structure measuring 10.38 [+ or -] 0.3 [micro]m with a diameter of 1 [micro]m opening to the exterior (Fig.
Pores scattered on dorsal and ventral surfaces of abdomen, but only one short, sensillum observed dorsally on a male's abdomen.
Figure abbreviations: ac--acrotergite; as--antecostal suture (ridge); br--transverse row of placoid sensilla on epipharynx; c--claw; cs--campaniform sensillum; dst--distal epipharyengal sensilla; dmr--dorsomesal row of setae on lacinia; er--epipharyngeal rods; f--femur; gl--galea; l--lacinia; lp--labial palp(i); mp--mesal pair of labro--epipharyngeal setae; msr--mesal row of setae on lacinia; mxp--maxillary palp(i); p2--2nd pair of labro-epipharyngeal setae; pr--pretarsus; pls--placoid sensilla; prst--prostheca; s--sensorium (accessory sensory papillae); sbp--subproximal epipharyngeal sensilla; st--stipes; t--tibia; tr--trochanter.
Targeted mutation of a Drosophila odor receptor defines receptor requirement in a novel class of sensillum. J.
5), PD, 3-5; trochanter, one small sensillum on the venter of lTr and one on the anterior face 2Tr of some specimens; femoral series, D, 4-5, AV+ADi.
Diagnosis: Antennal article VI with three sensilla basiconica, and diameter of the sensilla constant up to the attenuated apex, while the anterior sensillum is slightly shorter than the others.