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 ?
Moritz (1995) also described the exclusion of water from the spiracular atrium, or vestibule.
Weak dependence between spiracular structure and wing morph may be due to both body features being associated with microhabitat.
Posterior spiracles (Figs 24, 25): On extremely short stigmatophores, each with three radiating, elliptical, long and narrow stigmal openings (stigo) in a shamrock-shaped cuticular depression, surface between them smooth, positioned on a sub-triangular spiracular plate, ecdysial scar large, rounded and conspicuous; with four peristigmal tufts (Figs 24, 25, pstgt), inserted between stigmal openings on spiracular plate, broad and blade-like basally with 5-7 long, narrow undivided filaments.
pterothorax), slightly more pigmented legs and sometimes antennae, pale brown marginal and sometimes spiracular abdominal sclerites, and 25-43 scattered secondary sensoria on antennal segment IV, 5-19 aligned ones on segment IV and 0-2 on segment V.
However, the prothoracic spiracular apertures are typically bigger than the abdominal ones in the subgenera of Hyperomyzus.
Prothoracic spiracular Ucrimyzus villalobosi apertures no much larger than those on abdomen.
5 times as long as wide, sides curved, surface of both tergites smooth with 3 short seta at anterolateral angles and 2 short setae at posterolateral angles; both sterna without well- defined subdivisions, each smooth with a pair of discal setae near anterior margin; spiracular sclerite projecting strongly from lateral margin, spiracles (Fig.
Spiracular discpores each mainly with 5 loculi, in a band between each spiracle and stigmatic cleft, each band narrow near spiracles and broadening slightly nearer margin; also each band extending a short distance medially anterior to each spiracle; with about 30-50 pores in each anterior band and 45-70 in each posterior band; each band with 5-6 pores within area of sclerotization in each cleft with thickened margins.
Spiracular discpores each mainly with 5 loculi (range 4-7), in a more or less single line between each spiracle and stigmatic cleft; with about 4-8 (usually 7 or 8) in each anterior band and 4-10 (usually 8-10) in each posterior band.
1c), 2 kidney-shaped spiracular plates, each containing 3 wedge-shaped sections with serpentine spiracular slits (Fig.