hypostome


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Related to hypostome: basal disc

hypostome

[′hī·pə‚stōm]
(invertebrate zoology)
Projection surrounding the oral aperture in many cnidarian polyps.
Anteroventral part of the head in Diptera.
Median ventral mouthpart in ticks.
Raised area on the posterior oral margin in crustaceans.
References in periodicals archive ?
Mae'r hypostome yma wedi'i wneud o galch ac yn hynod o galed.
Key to the sub orders, families and genera: 1 With dentate faces of cheliceral digits directed externally (laterally), presence of a well developed hypostome provided ventrally with re-curved teeth; with lateral stigmatal openings behind coxae-IV or laterally above coxae II-III; prosoma completely fused; no trace of segmentation to the abdominal section; behind the legs size large, possession of true Haller's organ on the I pair of legs..........................................sub order Ixodida.
Nematocyst compliment represented by microbasic b-mastigophores of small size, 4.8-7.5 x 1.9-2.5 [micron]m on tentacles and hypostome. Isorhizas of two different sizes: (i) 8.0-9.1 x 1.6-2.0 [micron]m, not recorded from tentacles and, (ii) 5.1-8.0 x 1.0-1.6 [[micron]m less numerous throughout the colony.
The mouthparts consist of a pair of segmented palps (feelers), a pair of sharp-bladed chelicerae (pincers) that slice the skin, and a needlelike hypostome through which blood is sucked.
Inserting a syringelike hypostome, which is lined with backward-pointing teeth to lock it in place, they begin their feast.
b, c a Euglena a a Netrium a a (Phacus) a (Peridinium) a Scenedesmus d a, c a a a Staurastrum a a Herbivores Brachionus c a a Frontonia d a Hypostome sp.
Ontogeny, hypostome attachment and trilobite classification.
The glabella is broken off, revealing an external mould of a complete hypostome. Posteriorly the axial part of the internal mould preserves a slightly narrowing tube-like structure, which we interpret as a remnant of the alimentary canal.
Hypostome subrectangular in shape and cone shaped distally; with 4 pairs simple hypognathal setae (hg1-hg4) and 2 pairs adoral setae; with dot like lobes (Fig.
The repeated injection of saliva into bite wound incites a host reaction forming a straw-like hollow tube, the hypostome or stylostome, which extends downwards into the host's skin firmly anchoring the mite.
longirostre is the only species of Amblyomma that has lancet hypostome in nymphs (Figure 1.1) and in females.