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Nutmeg Family

Compsoneura mexicana (Hemsl.) Janovec, a tree in the Myristicaceae. Note the finely parallel tertiary veins, perpendicular to the midvein. Un árbol. Note las venas finas y paralelas, perpendiculares al eje principal.

Description: A family of medium to large trees, all characterized by simple, alternate leaves without stipules, and sap that oxidizes to a reddish color (blot it onto a piece of paper and wait for up to several minutes). The leaves are almost always distichous, and have a spicy odor when crushed. Many species also have stellate (star-shaped) hairs, visible through a hand lens. The most distinctive character of the Myristicaceae is their branching pattern. Many branches are produced at once, emerging in a whorl around the trunk, which gives the tree a pagoda-like architecture.

Myristicaceae fruits are dispersed by both birds and mammals. Here at La Selva, spider monkeys (Ateles geoffryi) and toucans (Ramphaistros spp.) are particularly important dispersers of Virola.

Economic uses: Myristica fragans, native to India, is the source of nutmeg and mace. In the Neotropics, native people use many Virola species in the preparation of hallucinogenic drugs for ceremonies.

Descripción: Una familia de árboles medianos a grandes. Todos tienen hojas simples y alternas, sin estípulas, y savia clara que se oxida a un color rojiza (hay que poner una mancha de exhudado en una tela o una hoja papel y esperar unos minutos para verlo). Las hojas casi siempre son dísticas, y tienen un olor a especias cuando se les estruja. Muchas especies también tienen pelos estrellados que se puede ver con una lupa de mano. La característica más llamativa de las Myristicaceas es su ramificación. Las ramas son verticiladas, lo que le da al tronco una apariencia de pagoda.

Los mamíferos y los pájaros dispersan las semillas de las Myristicaceas. En la Estación Biológica La Selva, monos araña (Ateles geoffryi) y tucanes (Ramphaistros spp.) son dispersadores muy importantes de los árboles del genero Virola.

Usos económicos: Myristica fragans, de India, es el fuente de la nuez moscada. En las zonas neotropicas, los indios usan varias especies de Virola para elaborar drogas halucinógenas rituales.

Genera/species at La Selva: 3/4 (all trees/ todos árboles): Compsoneura (1), Otoba (1), Virola (2)

FIELD MARKS – Myristicaceous branching featuring whorls of horizontal branches.

Virola2-ranked leaves (distichous) with prominent veins, fruit that splits to reveal a lacy red aril surrounding a single large seed.

Virola koschnyi showing “myristicaceous branching”. Looking up the trunk, the branches resemble the spokes on a bicycle wheel.
Virola showing myristicaceous branching.
Myristicaceous branching, also known as “pagoda branching,” consists of regularly spaced whorls of branches. The result is a layering effect of clusters of horizontal branches radiating from the trunk like spokes on a wheel interspersed by sections of trunk lacking any branches.
The trunk of Virola sebifera grows very straight, has fine vertical fissures, and often has a reddish-pink tint to its color.
Alternate leaves in two ranks (distichous), prominent venation, and stellate hairs are characteristic of the genus Virola.
The fruits of Virola split open to reveal a single large seed surrounded by a lacy red aril.
The fruits of Virola split open to reveal a single large seed surrounded by a lacy red aril. Large birds consume the arils of Virola and regurgitate the seeds unharmed.
There are two species of Virola at La Selva. They can be told apart by their leaf venation. Virola sebifera less than 15 sets of veins while Virola koschnyi has greater than 15 sets of veins per leaf.
Virola koschnyi with more than 15 sets of veins per leaf. Note the prominent venation.
Virola sebifera with less than 15 sets of veins per leaf.
Virola fruits open to reveal a single hard seed surrounded by a bright red fleshy mesh (aril). Toucans ingest the seeds, digest the aril and then regurgitate the hard seed.
Compsoneura mexicana leaves.
Compsoneura mexicana tree showing myristicaceous branching. The sap of this species turns orange/pink as it oxidizes.
Enlargement of Compsoneura leaf showing finely parallel tertiary veins.
Compsoneura mexicana fruits.
Looking up the straight, relatively smooth, trunk of Virola koschnyi.
Alternate leaves in a single flattened plane (distichous), prominent brown veins, and the number of veins (>15 sets) identifies this as Virola koschnyi.

< < Previous family: Moraceae
Next family: Myrsinaceae > >
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