spiracle

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spi·ra·cle

(spī'ră-kĕl, spir-),
An aperture for breathing in arthropods and cetaceans; a similar opening in sharks and related fishes.
[L. spiraculum, fr. spiro, to breathe]

spiracle

(spĭr′ə-kəl, spī′rə-)
n.
1. Zoology A respiratory aperture, especially:
a. Any of several tracheal openings in the exoskeleton of an insect, spider, or other terrestrial arthropod.
b. A small respiratory opening behind the eye of most sharks and rays and certain other fishes.
c. The blowhole of a cetacean.
2. An aperture or opening through which air is admitted and expelled.

spi·rac′u·lar (spī-răk′yə-lər, spĭ-) adj.

spiracle

  1. (in fish) a gill-like cleft that opens behind the eye and through which water is drawn in for gaseous exchange (as it is through the mouth) by the expansion of the pharyngeal cavity. It is absent in many bony fish.
  2. (in arthropods) the exterior opening of the tracheae, often possessing valves that can close to prevent water loss.

spiracle

small, circular openings in the exoskeleton of insects are the portal of entry for air into the insect body.
References in periodicals archive ?
Its is distinct, however with its closest relative (dromedarii) in having without lateral projections of basis capituli, dorsal posterior margin angular and deeply concave, conscutum with deep and long cervical grooves but very short marginal grooves, postero-median groove does not reach the parma, and remain separated, paramedian festoons parma generally rectangular and broad, large punctuations on caudal and lateral fields but sparse, however small punctuations always dense, transverse ridges present in caudal area, broad, angle of paraparmal festoons eject, sub-anal plates smaller in size and a very short dorsal prolongation of the spiracular plates and not clear from the body of the plate.
Evaporatoria greyish brown, other parts of ventral surface thorax and abdomen dark brown, prespiracular portions of spiracular callosities of abdominal sternites III-VII yellowish (Fig.
19); 2 pairs of trichobothria on abdominal segments 3-7, one aligned to the spiracle and other mesad of spiracular line (Fig.
Hissing via spiracular air expulsion is known to serve a defensive function in the blattid genus Gromphadorhina (Nelson 1979, Nelson & Fraser 1980) and at least one organism outside of snakes, the burrowing owl, incorporates mimicry of snake rattling in its defensive repertoire (Rowe et al.
Posterior spiracles asymmetrical, with 3 lobes, 2 with spiracular openings that radiate from the ecdysial scar (Fig.
Abdomen -- Segments 1-5 sclerotized dorsally, membranous laterally and ventrally, spiracles on or near lateral margins of tergites; segment 6 sclerotized dorsally, laterally, and ventrolaterally with only a narrow ventromedial area membranous or weakly sclerotized, spiracles well removed (at least 10 x spiracular diameter) from obscure ventrolateral margins; segments; 7 and 8 completely sclerotized, 7 with lateral spiracles; tergites of segments 4 and 5 with two longer darker sensilla on posterior margin, segments 6 and 7 with long, dark, posterodorsal and posteroventral sensilla originating in sclerotized areas, segment 8 relatively short (x = 1.
18, Moritz 1997), and the spiracular peritremes have a varied and complex structure (Moritz 1985).
They may be separated from Neoporus and Heterosternuta by the presence of spiracular openings on mesopleural regions and on tergites of abdominal segments 1 to 7 (8, 9).
All spiracular areas with 17 long, slender setae and 22 short, spine-like setae.
Membranous, very pale and with pale spiracular and inconspicuous intersegmental sclerites.