Calycobolus

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Calycobolus
Systematics
Nuclear eudicotyledons
Asterids
Euasterids I
Order : Nightshade (Solanales)
Family : Bindweed family (Convolvulaceae)
Genre : Calycobolus
Scientific name
Calycobolus
Willd. ex Roem. & Schult.
Calycobolus africanus , fruit

Calycobolus is a plant genus in the family of wind plants (Convolvulaceae). According to current opinion, 27–30 species that are common in Africa and America are included in it.

description

Vegetative characteristics

Calycobolus species are lianas with a woody trunk that grow climbing and are hairless or hairy with simple or T-shaped trichomes . The leaves are stalked, simple and have entire margins, at the base they are pointed, pointed or blunt, at the top they are pointed to blunt. The leaf blade is membranous to leathery, densely hairy with adjacent trichomes or glabrous and pinnately veined.

Inflorescences and flowers

The inflorescences are umbel-shaped to umbel- shaped thyrsenic and composed of several zymous partial inflorescences . They stand in the armpits or at the end on lateral branches. The peduncle can be hidden between the flowers or it can be relatively long. There are bracts formed that are either expensive or resistant.

The small to medium-sized flowers are only lightly or not fragrant. The five sepals appear in two forms: the outer two are larger and close together. Their shape can be heart-shaped, almost triangular, egg-shaped or broadly kidney-shaped, their base is heart-shaped, the tip rounded to pointed. The three inner sepals are significantly smaller and decrease in size towards the innermost, they enclose the base of the crown very tightly. Their shape can be egg-shaped or elliptical to rhombus-shaped. The crown is white in color and tubular to narrowly funnel-shaped. The coronet is almost completely or only slightly lobed and stands upright on the corolla tube.

The stamens are almost equally long, the anthers are white, elongated to linear-elongated. They open longitudinally without twisting. The pollen grains are not prickly, tricolpat and triaggricolpat . The two styluses are free from each other or are partially fused together below the middle. The two scars are head-shaped or depressed spherical.

Fruits and seeds

The fruits are ovoid to elliptical follicles or follicles -like fruits with one or two chambers that do not open up . They are surrounded by the enlarging, membranous calyx. They contain one to four seeds . These are egg-shaped to elliptical, black to brown and hairless. At its base there is a hilum, which is usually D-shaped.

distribution

The species of the genus occur predominantly in the humid tropics of Africa; only three species are known from South America .

Systematics

Within the family of wind plants (Convolvulaceae) the genus Calycobolus according to the scheme of Stefanovic et al. (2003) classified in the tribe Dichondreae . In the genus itself, 27 species are distinguished, 25 of which are native to Africa and three to America. A Mexican species, which was often included in the genus Calycobolus , is currently considered to be Porana nutans of the genus Porana .

Here is a selection of the types:

supporting documents

Individual evidence

  1. ↑ Saša Stefanovic, Daniel Austin and Richard Olmstead: Classification of Convolvulaceae: A Phylogenetic Approach (PDF file; 310 kB). In: Systematic Botany , Volume 28, Number 4, 2003. pp. 791-806.
  2. ↑ a b c d e f g Rafaël Govaerts (Ed.): Calycobolus. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved November 23, 2017.

literature

  • GW Staples and DF Austin: Revision of Neotropical Calycobolus and Porana (Convolvulaceae) . In: Edinburgh Journal of Botany , Volume 66, Number 1, 2009. pp. 133-153. doi : 10.1017 / S0960428609005319