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Related to rostellum: oncosphere, coracidium


n. pl. ros·tel·la (rŏ-stĕl′ə)
A small beaklike part, such as a projection on the stigma of an orchid or the hooked projection on the head of a tapeworm.

[Latin, diminutive of rōstrum, beak; see rostrum.]

ros·tel′lar adj.


n, pl -la (-lə)
(Biology) biology a small beaklike process, such as the hooked projection from the top of the head in tapeworms or the outgrowth from the stigma of an orchid
[C18: from Latin: a little beak, from rōstrum a beak]
rosˈtellate, rosˈtellar adj


(rɒˈstɛl əm)

n., pl. ros•tel•la (rɒˈstɛl ə)
1. any of various small, beaklike parts, as the mouth tube of sucking bugs or the hook-bearing projection of intestinal tapeworms.
2. a beaklike modified stigma of certain orchids that secretes a sticky fluid, enabling pollen grains to adhere to visiting insects.
[1750–60; < New Latin; Latin: little beak, snout, diminutive of rōstrum snout (see rostrum); for formation, see castle]
References in periodicals archive ?
An anterior cone shaped rostellum surrounded with two layers of hooks and four rounded suckers were observed (Fig.
Members of the newly proposed genus Versteria have morphologic features that distinguish them from members of the other taeniid genera, such as miniature rostellar hooks, small scolex, rostellum, and suckers; a short strobili; and a small number of testes (1).
8 mm wide; rostellum triangular, rounded, after removal of the pollinarium the rostellum remnant laminar, triangular-ovate, three-toothed, middle tooth narrowly triangular, lateral teeth about one-third the length of the middle tooth.
The scolex has four suckers and a conical, retractile rostellum "armed" with 1-8 rows of hooks, depending on the age of the parasite.
2) The majority of orchid flowers attach pollinia indirectly to an adhesive plug (the viscidium) using stalk-like, connective structures produced by the anthers (caudicles) or the rostellum (stipes).