Involucre


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Related to Involucre: raceme, pappus

involucre

[′in·və‚lü·kər]
(botany)
Bracts forming one or more whorls at the base of an inflorescence or fruit in certain plants.

Involucre

 

the small, tightly packed apical leaves that surround an inflorescence. In plants of the families Compositae and Dipsacaceae, the involucre closely surrounds the inflorescence; as a result, the involucre and the inflorescence appear to form a single flower. In plants of the family Umbelliferae, the involucre is located at the base of the inflorescences, or compound umbels. The leaves at the base of a simple umbel form an involucel. The morphological characteristics of involucres and involucels are used in the taxonomy of the various families.

References in periodicals archive ?
Capituleseences terminal, laxly racemose to corymbose, on long peduncles; capitula pedunculate, heterogamous, disciform; receptacle epaleate; involucre uniseriate.
Capitulescences monocephalous, on scapes; capitula heterogamous, disciform or radiate, chasmogamous or cleistogamous, erect or nodding; receptacle epaleate; involucre multiseriate.
Capitulescences monocephalous or two- to three-headed, terminal; capimla pedunculate, homogamous or occasionally heterogamous, discoid; receptacle epaleate; involucre multiseriate.
Capitulescences monocephalous, terminal; capitula sessile to short-pedunculate, homogamous, radiate; receptacle epaleate; involucre multiseriate, six- to ten-seriate, phyllaries acute or with showy, orbicular to spatulate, laciniate apical appendages.
Capitulescences monocephalous, terminal, erect to pendulous; capitula pedunculate, heterogamous, rarely homogamous, discoid or radiate; receptacle epaleate; involucre multiseriate, phyllaries erect to recurved downward.
Capitulescences monocephalous, terminal or axillar; capitula sessile on the brachyblasts, homogamous, ligulate, five- to seven-flowered; receptacle epaleate; involucre uniseriate, phyllaries ca.
Capitulescences cymose, two- to nine-headed, subterminal to lateral, rarely monocephalous; capitula pedunculate, homogamous, bilabiate, two- to five-flowered; receptacle epaleate; involucre multiseriate, cylindrical, phyllaries glabrous.
Capitulescences monocephalous or in loose to dense apical cymes; capitula short-pedunculate, homogamous, discoid or disciform; receptacle epaleate; involucre multiseriate.
Capitulescences mono cephalous, on scapes; capitula homogamous, discoid or radiate; receptacle epaleate; involucre two- to three-seriate.
Capitulescences a dichotomous cyme; capitula pedunculate, homogamous, discoid; receptacle paleaceous, paleae embracing all the florets; involucre one- to two-seriate.
This group of species constitute the genus Cloiselia (Ortiz, 2006a), characterized by corollas much longer than the involucre, disc floret epidermal cell cuticle ornamentation "intestine-like," long simple (not twin) hairs on disc florets corolla, stamen insertion near the corolla base, and pollen echinate, among other characters.
Capitulescences monocephalous or in cymes; capitula sessile to pedunculate, homogamous, discoid; receptacle epaleate; involucre multiseriate.