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Related to involucral: bracteole


A group of one or more whorls of bracts beneath a flower or flower cluster.

[French, from Latin involūcrum, wrapper, envelope; see involucrum.]

in′vo·lu′cral (-krəl), in′vo·lu′crate (-krĭt, -krāt′) adj.
References in periodicals archive ?
All the weeds of Asteraceae family also herbaceous, leaves variable with pinnate venation and Inflorescence a head (capitulum) with many flowers with involucral bracts surrounding it, or tongue-shaped (ligulate).
All the weeds of asteraceae family also herbaceous, leaves variable with pinnate venation and Inflorescence a head (capitulum, A) with many flowers with involucral bracts surrounding it (B Flowers small, either tubular (C), or tongue-shaped (ligulate).
(1995) for zebra fish, in which the blastoderm is formed by a single outer layer of flattened cells, known as the involucral outer layer, and a more rounded deep layer of cells.
tuberosus, though the former presents much narrower leaves and tightly appressed involucral bracts that do not surpass the tubular flowers as the latter do (Aizpuru & al., 1999).
Staminate inflorescences capitate, 10-12 flowered in a single raceme, peduncle to 10 mm long, pedicels up to 1 mm long; perianth campanulate, 6 mm long, 6-lobed, each lobe 1 mm long; stamens 6 alternate with perianth lobes, anthers bilocular, dorsifixed, elliptic < 1 mm diameter, extrorse, generally 1 or 2 reduced to staminodes; the fine filaments connate basally, borne at the base of a pistillode 3 mm long; lower part of the perianth reduced to 2 or 3 small involucral bracts; indumentum densely short velutinous.
Approximately 30 days later, the eggs hatch and the larvae burrow into the involucral bracts until they reach the seeds, where they feed (Fig.
Involucral bracts hairy, nearly orbicular, broad hyaline-margined and florets pale yellow.
Inflorescence broadly capitate, simple, umbellate, apex nearly flat, sunk in the center of the rosette, 8-9 cm long (excluding the petals), 9-12 mm in diameter, 56 to 65-flowered; floral bracts entire to remotely denticulate at the apex, green, membranaceous, distinctly nerved, longitudinally sulcate mainly near the apex, sparsely to subdensely white-lepidote outside, glabrous inside, the outer ones resembling the involucral bracts, ecarinate, slightly exceeding the ovary, the inner ones narrowly ovate-lanceolate to sublinear-lanceolate, acuminate, ecarinate or bearing a protruded central nerve and appearing carinate, 45-60 x 8-20 mm, slightly exceeding the ovary.