Cephalotaxaceae

Cephalotaxaceae
Cephalotaxaceae
a Cephalotaxaceae species:
Cephalotaxus harringtonii
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Cephalotaxaceae
Neger
Genera

Amentotaxus
Cephalotaxus
Torreya

The family Cephalotaxaceae is a small grouping of conifers, with three genera and about 20 species, closely allied to the Taxaceae, and included in that family by some botanists. They are restricted to east Asia, except for two species of Torreya found in the southwest and southeast of the USA; fossil evidence shows a much wider prehistorical northern hemisphere distribution. The differences between the two families are as follows:

Family Taxaceae Cephalotaxaceae
Cone aril partly encloses seed fully encloses seed
Cone maturation 6-8 months 18-20 months
Mature seed length 5-8 mm * 12-40 mm

* To 25 mm in Austrotaxus

These are much branched, small trees and shrubs. The leaves are evergreen, spirally arranged, often twisted at the base to appear 2-ranked. They are linear to lanceolate, and have pale green or white stomatal bands on the undersides. The plants are monoecious, subdioecious or dioecious. The male cones are 4-25 mm long, and shed pollen in the early spring. The female cones are reduced, with one to a few ovuliferous scales, and one seed on each ovuliferous scale. As the seed matures, the ovuliferous scale develops into a fleshy aril fully enclosing the seed. The mature aril is thin, green, purple or red, soft and resinous. Each ovuliferous scale remains discrete, so the cone develops into a short stem with one to a few berry-like seeds. They are probably eaten by birds or other animals which then disperse the hard seed undamaged in their droppings, but seed dispersal mechanisms in the family are not yet well researched.

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Look at other dictionaries:

  • Cephalotaxaceae — Cephalotaxaceae …   Wikipédia en Français

  • Cephalotaxaceae — Saltar a navegación, búsqueda ? Cephalotaxaceae Cephalotaxus harringtonii …   Wikipedia Español

  • Cephalotaxaceae — Cephalotaxaceae …   Wikipédia en Français

  • Cephalotaxaceae — Kopfeiben Japanische Kopfeibe (Cephalotaxus harringtonia) Systematik Überabteilung …   Deutsch Wikipedia

  • Cephalotaxaceae — noun a family of Cephalotaxaceae • Syn: ↑family Cephalotaxaceae, ↑plum yew family • Hypernyms: ↑gymnosperm family • Member Holonyms: ↑Coniferales, ↑order Coniferales …   Useful english dictionary

  • Cephalotaxaceae — La Cepahlotaxaceae es una pequeña familia de coníferas, con alrededor de 20 especies, ligada a la familia Taxaceae, incluida dentro de dicha familia por algunos botánicos …   Enciclopedia Universal

  • Семейство головчатотиссовые (Cephalotaxaceae) —         Семейство представлено одним родом головчатотиссом (Cephalotaxus), состоящим всего из 6 видов. Филогенетически головчатотиссовые тесно связаны с только что представленным читателю семейством подокарповых, особенно с примитивными… …   Биологическая энциклопедия

  • family Cephalotaxaceae — noun a family of Cephalotaxaceae • Syn: ↑Cephalotaxaceae, ↑plum yew family • Hypernyms: ↑gymnosperm family • Member Holonyms: ↑Coniferales, ↑order Coniferales …   Useful english dictionary

  • Céphalotaxacée — Cephalotaxaceae Cephalotaxaceae …   Wikipédia en Français

  • Céphalotaxacées — Cephalotaxaceae Cephalotaxaceae …   Wikipédia en Français

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