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Related to spiracular: Spiracles


 (spĭr′ə-kəl, spī′rə-)
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.

[Middle English, from Latin spīrāculum, from spīrāre, to breathe.]

spi·rac′u·lar (spī-răk′yə-lər, spĭ-) adj.
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References in periodicals archive ?
Spiracular disc-pores (spdp) each with 5 loculi, rarely a few pores with fewer or more loculi, present in a single irregular row extending laterally from each spiracle to body margin.
edule in Costa Rica had between 7 to 15 circular pores within each spiracular area of abdominal tergite II (Fig.
ACVF, anterior cerebral vein foramen; AFPC, anterior foramen for preorbital canal; ANTO, antorbital condyle; ELF, endolymphatic foramen; ES, eye stalk; ESAF, efferent spiracular artery foramen; F, fontanelle; FM, foramen magnum; ICAF, internal carotid artery; LC, lateral commissure; NC, nasal capsule; OC, occipital condyle; OF, orbital fissure; PFPC, posterior foramen for preorbital canal; PLF, perilymphatic foramen; PROP, preorbital process; POST, postorbital process; R, rostrum; SOC, supraorbital crest; II, optic nerve foramen; IV, trochlear nerve foramen; VII, hyomandibular branch of facial nerve foramen; X, vagus nerve foramen.
Segments 1-5 with heavily sclerotized and distinct dorsal plates, membranous laterally and ventrally, 6 heavily sclerotized dorsally and laterally, segments 7 and 8 completely sclerotized; sensilla numerous on all segments with shorter sensilla dominant ventrally; spiracular openings absent on 1-7; segment 8 dorsal length 0.
dendrobii is characterized by having 3 to 5 cribriform plates on each side of body; anterior and posterior spiracular setae present; posterior spiracular furrows divided; antennae 7- to 9-segmented; legs rudimentary (Howell and Kosztarab, 1972; Miller et al.
Ocular and spiracular thorns present, nuchal thorn absent, no other thorns on the disc.
Each spiracular plate (Sp) with four palmate interspiracular processes (IP), alternating with three spiracular openings.
This species having five to ten spiracular bristles but without postspiracular bristle.
The morphological characters examined were the pseudocephalon, cephalopharyngeal skeleton, spinules, spiracular atrium and the posterior spiracles.
7 times width at spiracles; secondary tubercles not pronounced and not far spaced from spiracular tubercles.
1d) yellow to yellowish-brown in coloration, almost smooth, squarish in shape with spiracular tubercles prominent.
The posterior spiracles are slightly raised and the spiracular openings are sinuous slits which are completely surrounded by an oval black border (Figure 1).