Cephalotaxaceae (lat. Cephalotaxaceae) iynəyarpaqlılar dəstəsinə aid bitki fəsiləsi.
Amentotaxus
Cephalotaxus
Torreya
Cephalotaxaceae (lat. Cephalotaxaceae) iynəyarpaqlılar dəstəsinə aid bitki fəsiləsi.
Blommetaks-familien (Cephalotaxaceae) er en lille familie med tre slægter, der står Taks-familien nær. Den olivenagtige (eller altså: blommeagtige) frugt modner dog først efter to år.
Slægter
Cephalotaxus, commonly called plum yew or cowtail pine, is a genus of conifers comprising 11 species, either considered the only member of the family Cephalotaxaceae, or in the Taxaceae when that family is considered in a broad sense.[1][2] The genus is endemic to eastern Asia, though fossil evidence shows it had a wider Northern Hemisphere distribution in the past.[1] The species are evergreen shrubs and small trees reaching 1.0–10 metres (3–33 ft) (rarely to 20 metres (66 ft)) tall.
Molecular studies place Cephalotaxus as the most basal member of the Taxaceae, having a very ancient divergence from them during the late Triassic.[3] Historically, it was placed as the only member of the family Cephalotaxaceae, due to strong morphological differences from other members of Taxaceae,[4] but major authorities consider the family synonymous with Taxaceae.[5][6]
The leaves are spirally arranged on the shoots, but twisted at the base to lie in two flat ranks (except on erect leading shoots); they are linear, 4–12 centimetres (1+1⁄2–4+3⁄4 in) long and 3–4 millimetres (1⁄8–5⁄32 in) broad, soft in texture, with a blunt tip; this helps distinguish them from the related genus Torreya, which has spine-tipped leaves.[2]
The species can be either monoecious or dioecious; when monoecious, the male and female cones are often on different branches. The male (pollen) cones are 5–8 millimetres (13⁄64–5⁄16 in) long, grouped in lines along the underside of a shoot. The female (seed) cones are single or grouped two to 15 together on short stems; minute at first, they mature in about 18 months to a drupe-like structure with the single large nut-like seed 1.5–4 centimetres (5⁄8–1+5⁄8 in) long surrounded by a fleshy covering, green to purple at full maturity. Natural dispersal is thought to be aided by squirrels which bury the seeds for a winter food source; any seeds left uneaten are then able to germinate.[2]
Cephalotaxus species produce cephalotaxine, an alkaloid. Parry et al 1980 provides evidence that cephalotaxine is a phenylethylisoquinoline. However, they also find this genus to be unable to incorporate cinnamic acid into cephalotaxine, and incorporation of cinnamic acid is usually a step in phenylethylisoquinoline syntheses, throwing the phenylethylisoquinoline theory in to question.[7]
The taxonomy of Cephalotaxus is difficult, because the species have been defined using characteristics that intergrade with each other, such as the length and shape of needles, bark, and stomatal band color. Cephalotaxus species have often been separated geographically rather than morphologically.[8]
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(help) Cephalotaxus, commonly called plum yew or cowtail pine, is a genus of conifers comprising 11 species, either considered the only member of the family Cephalotaxaceae, or in the Taxaceae when that family is considered in a broad sense. The genus is endemic to eastern Asia, though fossil evidence shows it had a wider Northern Hemisphere distribution in the past. The species are evergreen shrubs and small trees reaching 1.0–10 metres (3–33 ft) (rarely to 20 metres (66 ft)) tall.
Cephalotaxaceae, son una familia del Orden Pinales. Esta pequeña familia de coníferas, con alrededor de 20 especies, se encuentra relacionada con la familia Taxaceae, e incluidas en esa familia por algunos botánicos. Están restringidas al este de Asia, excepto en lo que se refiere a dos especies de Torreya que se encuentran en el suroeste y sudeste de los Estados Unidos; la evidencia fósil muestra una distribución mucho más amplia en el Hemisferio norte prehistórico. Las diferencias entre las dos familias son las siguientes:
* Hasta 25 mm en Austrotaxus
Se trata de arbustos o pequeños árboles con muchas ramas. Las hojas son perennes, dispuestas en espiral, a menudo retorcidas en la base para aparecer en dos filas. Son lineales a lanceoladas, y tienen bandas estomatales de color verde claro o blancas por el envés. Las plantas son monoicas, subdioicas o dioicas. Los estróbilos masculinos tienen 4-25 mm de largo, y lanzan el polen a principios de la primavera. Los conos femeninos son reducidos, con una a unas pocas escamas ovulíferas, y una semilla en cada escama ovulífera. Conforme la semilla madura, la escama ovulífera se desarrolla en un arilo carnoso que rodea por completo a la semilla. El arilo maduro es delgado, verde, púrpura o rojo, suave y resinoso. Cada escama ovulífera permanece discreto, de manera que el cono se desarrolla como una rama corta con una a varias semillas de bayas. Son probablemente comidas por las aves y otros animales que luego dispersan la semilla dura sin lesionar en sus deposiciones, pero los mecanismos de dispersión de semillas en la familia no están todavía bien investigados.
Peajugapuulised (Cephalotaxaceae) on igihaljaste okaspuude sugukond okaspuulaadsete seltsist.
Peajugapuuliste sugukonda kuulub kolm perekonda ja umbes 20 liiki. Mõnikord arvatakse peajugapuulised jugapuuliste sugukonda.
Sugukonda kuuluvad tugevalt hargnevad väikesekasvulised puud ja põõsad, mis kasvavad valdavalt Ida-Aasias; üksnes kaht pähkeljugapuu liiki on leitud ka Põhja-Ameerikast.
Peajugapuulised (Cephalotaxaceae) on igihaljaste okaspuude sugukond okaspuulaadsete seltsist.
Peajugapuuliste sugukonda kuulub kolm perekonda ja umbes 20 liiki. Mõnikord arvatakse peajugapuulised jugapuuliste sugukonda.
Sugukonda kuuluvad tugevalt hargnevad väikesekasvulised puud ja põõsad, mis kasvavad valdavalt Ida-Aasias; üksnes kaht pähkeljugapuu liiki on leitud ka Põhja-Ameerikast.
La famille des Céphalotaxacées regroupe des plantes pinophytes (ou conifères) ; elle comprend 20 espèces réparties en 3 genres, parfois inclus dans les Taxacées :
La famille des Céphalotaxacées regroupe des plantes pinophytes (ou conifères) ; elle comprend 20 espèces réparties en 3 genres, parfois inclus dans les Taxacées :
Amentotaxus (parfois inclus dans les Taxaceae) Cephalotaxus Siebold et Zucc. ex Endl. Torreya Arn. (parfois inclus dans les Taxaceae) Branche d'Amentotaxus avec aiguilles. Klondike Mountain, Ferry County, Washington, USA, Eocène, Yprésien (49 million d'années), Largeur : 6,2 cmCephalotaxaceae é uma pequena família de coníferas, constituida por três géneros e 20 espécies. São próximas da família Taxaceae e alguns taxonomistas chegam mesmo a incluí-las nela.
Estão restritas à Ásia oriental, com excepção de 2 espécies do género Torreya, encontradas nos EUA.[1]
Cephalotaxaceae é uma pequena família de coníferas, constituida por três géneros e 20 espécies. São próximas da família Taxaceae e alguns taxonomistas chegam mesmo a incluí-las nela.
Estão restritas à Ásia oriental, com excepção de 2 espécies do género Torreya, encontradas nos EUA.
개비자나무과(-榧子--科, 학명: Cephalotaxaceae 케팔로탁사케아이[*])는 과거에 인정되었던 과이다. 구과목의 식물로 3속 20종이 포함된다. 주목과(Taxaceae)와 가깝다. 상록관목 또는 교목으로 잎은 가지에 밀생하여 2열로 난 것처럼 보이며 선형이다. 꽃은 암수딴그루이나 드물게 암수한그루인 경우도 있다. 수꽃은 잎겨드랑이에 구형 또는 수상(穗狀)의 구화(毬花) 모양의 꽃차례를 이루며, 수술은 7-12개가 달려 있다. 회사는 짧고, 꽃밥은 3실로 이루어져 있다. 암꽃은 작은 가지의 기부에 달리고, 2개의 밑씨를 가진 여러 쌍의 대포자엽으로 구성된다. 씨는 1-2개로 타원형이며 핵과 모양이다. 육질의 종피와 얇은 목질의 내피를 가졌다.
개비자나무과(-榧子--科, 학명: Cephalotaxaceae 케팔로탁사케아이[*])는 과거에 인정되었던 과이다. 구과목의 식물로 3속 20종이 포함된다. 주목과(Taxaceae)와 가깝다. 상록관목 또는 교목으로 잎은 가지에 밀생하여 2열로 난 것처럼 보이며 선형이다. 꽃은 암수딴그루이나 드물게 암수한그루인 경우도 있다. 수꽃은 잎겨드랑이에 구형 또는 수상(穗狀)의 구화(毬花) 모양의 꽃차례를 이루며, 수술은 7-12개가 달려 있다. 회사는 짧고, 꽃밥은 3실로 이루어져 있다. 암꽃은 작은 가지의 기부에 달리고, 2개의 밑씨를 가진 여러 쌍의 대포자엽으로 구성된다. 씨는 1-2개로 타원형이며 핵과 모양이다. 육질의 종피와 얇은 목질의 내피를 가졌다.
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