Asclepiadaceae

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Asclepiadaceae

[ə‚sklēp·ē·ə′dās·ē‚ē]
(botany)
A family of tropical and subtropical flowering plants in the order Gentianales characterized by a well-developed latex system; milkweed (Asclepias) is a well-known member.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Asclepiadaceae

 

(milkweed), a family of dicotyledonous plants. They are creeping, climbing, or erect shrubs or subshrubs and herbs; these plants are rarely trees. The leaves are generally opposite, entire, and exstipulate. The flowers are bisexual, usually regular, and five-petaled. The corolla is sympetalous and often has a crown. The stamens and the gynoecium form a gynostegium. The pollen grains are in pollinia; more rarely they are in tetrads. The distinctive structure of the flower is adapted to cross-pollination by insects. The fruit has two follicles, which are somewhat fork-shaped and resemble a swallow’s tail. The seeds usually have a pappus of silky fibers. Plants of the family Asclepiadaceae are characterized by the presence of a milky juice (often poisonous) and intraxylary phloem (bast).

There are approximately 290 genera (2,000 species), distributed primarily in tropical regions; some species are also encountered in subtropical and temperate regions. Eight or nine genera, comprising approximately 40 species, are found in the USSR. The most important genera include Asclepias (milkweed), Vinatoxicum, and Periploca. There are many poisonous, medicinal, and ornamental plants in this family (condurango, wax plant, and stapelia); some species yield dye substances and fiber (species of Marsdenia and Calotropis).

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
2011b Hoya medinillifolia (Apocynaceae Asclepiadoideae), a new species from lowland forests of Sarawak, Borneo.
2011 Hoya wongii (Apocynaceae, Asclepiadoideae): a new campanulate flowered species from Brunei (Borneo).
2013 Hoya nuttiana (Apocynaceae, Asclepiadoideae), a new species from Sarawak, Malaysian Borneo, Phytotaxa 140 (l):56-60.
This suggests the arrangement in the Asclepiadoideae, and the same pairing of pollinia has been observed in three genera of the Secamonoideae: Genianthus (Klackenberg, 1995b), Secamone (Civeyrel, 1994), and Secamonopsis (Civeyrel, 1996).
Much of his reasoning is based on his interpretation of the differences in the bases of the stamens between the Periplocoideae and the Asclepiadoideae. For the Periplocoideae he described the swollen region below the filaments as the "basal tube" and interpreted it as corolline or receptacular (Kunze 1990: 38).
In his later paper Kunze (1996: 567) stated that the filament tube in the Asclepiadoideae has evolved by "replacement of the original free filaments by new elements originating from the inward[ly] protruding base[s] of the filaments." He stated as well that these results refute his hypothesis that the basal part of the "asclepiad filament tube is of receptacular origin" and that, consequently, the "basal tube in the Periplocaceae and the [basal part of the] filament-tube in the Asclepiadaceae are not homologous" (p.
Another important fact is that while the situation described in the third stage leads naturally (in our view) to that in the Asclepiadoideae, the arrangement in first stage is similar to that in various Rauvolfioideae and Apocynoideae (cf.
Further aspects lend support to the existence of a cline from the Periplocoideae to the Asclepiadoideae. One is the position of the retinacle: When the filament is present, it lifts the anther above the thickest portion of the style head, so that the five anthers are connivent above it and are fused to the style head above its thickest portion (e.g., Fig.
This situation again bears considerable similarity to many coronas found in the Asclepiadoideae.
In the Asclepiadoideae the primary nectaries are located behind the guide rail at the top of the so-called filament tube and above the filaments.
When Robert Brown (1810a, 1810b) separated the Asclepiadaceae from the Apocynaceae, he recognized three groups within the former: the "Asclepiadeae verae" (= Asclepiadoideae), the Periploceae, and an unnamed third group that contained only Secamone.