spiracle


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spiracle

1. any of several paired apertures in the cuticle of an insect, by which air enters and leaves the trachea
2. a small paired rudimentary gill slit just behind the head in skates, rays, and related fishes
3. any similar respiratory aperture, such as the blowhole in whales
4. Geology a protrusion of sediment into a lava flow, formed by the explosive transition of water into steam

spiracle

[′spir·ə·kəl]
(invertebrate zoology)
An external breathing orifice of the tracheal system in insects and certain arachnids.
(vertebrate zoology)
The external respiratory orifice in cetaceous and amphibian larvae.
The first visceral cleft in fishes.
References in periodicals archive ?
Donaldson noted that the DMF muffler employs series-mounted, flow-through filters capable of reducing tailpipe emissions of particulate matter by 70 percent, with application of the Spiracle crankcase filter bringing total engine reductions to nearly 80 percent.
I immobile, but alive, reacting to irritation, spiracles beginning to work actively after being placed in seawater.
Xenopus tadpoles were used because they have a spiracle on both sides which might help determine the role of the spiracle in forelimb emergence.
Prothoracic spiracle setiform and well developed (length: 0.23 mm).
conspicua has four pairs of terminal papillae (larva) and a shorter prothoracic spiracle, while the new species presents only two pairs of terminal papillae and a longer prothoracic spiracle.
(iii) Character number 3--female with spiracle on eighth abdominal segment opening on membrane (versus on tergite).
15) with tergite I smooth, with lateromedian longitudinal carinae quite strong, present on anterior 0.6; tergite I in lateral view, with spiracle positioned anterior to centre, about 0.3 of way along, base with a rather rounded lateral tooth, margin pointing laterally (Fig.
Spiracle sare holes in the side of the body which help in the exchange of oxygen and carbon dioxide as part of re spiration.
Abdominal spiracles I shorter than spiracles II-VIII; spiracles on segments II and IV equal in size; spiraeles on segments V and VI equal in size; spiracle of segments VII and VIII larger than preceding spiracles.
Through stages P9-P14, intense stain was associated with the anterior spiracle region, along the line of the first dorsal anastomosis and into the dorsal tracheal trunks [ILLUSTRATION FOR FIGURE 6F OMITTED] (anatomy after Whitten, 1980).
Thorax: upper and lower frontal horn absent, a pair of lower facial papillae (one setose and one bare) each side of midline, three lateral papillae (one setose and two bare) each side of midline, prothoracic spiracle cylindrical, 0.9 mm (Figure 10); wing reaching fourth abdominal segment; first and third pairs of legs reaching seventh abdominal segment, second pair reaching eighth.
The lateral view shows the horizontal propodeal spiracle on the lateropropodeum.