gynostemium


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gynostemium

(ˌɡaɪnəʊˈstiːmɪəm)
n
the central reproductive stalk of an orchid, which consists of a stamen and pistil fused together
Translations
Gynostemium
References in periodicals archive ?
Roles of synorganisation, zygomorphy and heterotopy in floral evolution: the gynostemium and labellum of orchids and other lilioid monocots.
Length Width (mm) (mm) Petals 2 free 35 [+ or -] 2 3.0 [+ or -] 0.1 1 labellum 17.0 [+ or -] 1.1 27.0 [+ or -] 2.1 Sepals 3 free 35 [+ or -] 3 5.0 [+ or -] 0.4 Gynostemium 8.0 [+ or -] 0.9 4.5 [+ or -] 0.5 Peduncle + ovary 6.0 [+ or -] 0.5 2.0 [+ or -] 0.2 Color Petals 2 free White, slightly yellowish 1 labellum White, with lime-green nectar guides at the base Sepals 3 free White, slightly yellowish Gynostemium White Peduncle + ovary Green Table 2.
Two of the plesiomorphic characters of Aristolochia are the presence oia completely inferior ovary formed by the congenital fusion of six carpels, and the congenital fusion of the six stamens with the stylar portion of the carpels, forming the typical gynostemium in the genus (Gonzalez, 1999b; Gonzalez & Stevenson, 2000, 2002; Kelly & Gonzalez, 2003).
4 B, C), 17-26 x 7-11 mm, forming an angle ofabout 140-180[degrees]] with the tube, acute at the apex; gynostemium about 3.5 x 1.5 mm.
(2) The Rafflesiales (Brown, 1821; Bartling, 1830; Solereder, 1889b; Delpino, 1893; Baldacci, 1894; Hutchinson, 1969; Endress, 1990, 1994; Kubitzki, 1993), based on the similarities in floral structure, particularly the presence of a simple, fleshy, sapromyophilous perianth, with connate portions and a ring-like structure at the entrance, the extrorse anthers, the fusion of stamens and styles into a gynostemium, the ring-like, uninterrupted stigmas, and the inferior, pluriovulate ovary.
This subfamily (equivalent to the tribe Aristolochiineae sensu Huber, 1985, 1993), as proposed by Schmidt (1935), is supported by the following synapomorphies: monosymmetric, tubular perianth differentiated into utricle, tube and limb; and six uniseriate stamens, which are fused with the styles/stigmas forming a gynostemium (Gonzalez, 1997).
1, 11), on the basis of differences in the morphology of the perianth and the gynostemium. Most of the segregate genera correspond to infrageneric taxa proposed by authors such as Duchartre (1854a, 1864), and Schmidt (1935)(Table 3).
1., based on the perianth morphology and the number of gynostemium lobes: Subgenus Siphisia, with a 3-lobed perianth and 3-lobed gynostemium, which is essentially Duchartre's (1854a, 1864) Group I; subgenus Pararistolochia, with a 3-lobed perianth, and 6-12-lobed gynostemium, which is based on the genus Pararistolochia proposed by Hutchinson & Dalziel (1927); and subgenus Orthoaristolochia, with a 1-2-lobed perianth and 5-6-lobed gynostemium, which equals Group II of Duchartre (1854a, 1864).
The characters that define sections, subsections, series and subseries are based on the morphology of the perianth and the gynostemium.
Synapomorphies of the Aristolochioideae include: perianth differentiated into utricle, tube, and limb (character 25), adaxially curved (26), stamens sessile (45) and fused to the stigmas into a gynostemium (43).