Cryosophila

Cryosophila warscewiczii, inflorescence

Cryosophila is to Colombia, occurring from Mexico palm genus. A characteristic feature of the genus are seated on the trunk branched root thorns. The palm trees grow in the understory primarily of moist tropical forests of the lower altitudes. Half of the ten species is considered endangered.

• 5.1 Notes and references

Features

Trunks and root thorns

The representatives of Cryosophila are single -stemmed palm trees, rarely more stocky. The tribes wear long and branched root thorns. The trunk is between 0.5 and 15 m high and has a diameter of 4 to 20 cm. In most species the trunk is straight and upright. Sometimes, especially on sloping sites, the trunk on a saber growth.

The thorns are modified roots. This was first recognized by Wendland 1869. They arise endogenously the trunk and have the anatomy of a typical monocot root, such as a polyarches central vascular bundle. In the course of the spike growth, the root cap falls off, the base fabric is sclerotic, and the root end differentiates into a sharp point. The distribution of spines along the trunk is very variable, but there are two basic patterns: in most species they are at the lower stem end closest and thin towards the top of; at Cryosophila bartlettii, Cryosophila grayumii and Cryosophila kalbreyeri they are distributed more evenly.

There are two groups of root - thorns: " root" spines are rather directed downward, rather short and have a round cross section. " Crown" spines are rather ascending, long and compressed. They are found between the leaf bases, so stand at the internodes and fall off with the leaves.

The thorns are simply branches usually, sometimes two or three times. The side branches also develop into spines. The length of the spikes ranges depending on the type of less than 3 cm to about 15 cm.

At the base of the trunk, the adventitious roots do not develop into spines, but penetrate into the soil. Often forms at the base of a cone of roots.

The crown is generally made ​​15 to 25 sheets, the breadth ranges from 5 to 35. The leaves are spirally arranged, forming a spreading crown. The leaf stems are 40-320 cm long and wide at the narrowest point 0.6 to 3.3 cm. The petiole base is cleaved to mature in all species except Cryosophila. For juvenile leaves and the youngest leaves the base is not split. The Hastula, the scale- like extension of the petiole on the point of attachment of blade out, is usually short and triangular.

The leaf blade is folded and hand - or fan-shaped. Along or near the midrib, the leaf is split so that two halves of the leaf arise. This central gap comes close to five cm or less at the Spreitenbasis, except for Cryosophila williamsii and Cryosophila cookii. The lamina consists of 30 to 80 segments. The central segment is 40 to 160 cm long, more than a meter but only Cryosophila cookii, Cryosophila guagara and Cryosophila macrocarpa. The leaf blade is divided by two types of columns on: deep primary, adaxial columns that divide the lamina into a number of mostly multi-segmented sections; and less profound secondary columns.

The underside of the leaf blade is finely hairy, the hairs are long and thin. The lower leaf surface therefore appears whitish to silvery.

The midrib of the leaf segments are large, yellow and very stiff. The stiffness is due to a continuous fiber cylinder, which makes up the majority of the rib. This cylinder surrounds a colorless base fabric in the middle of one or more large vascular bundles are embedded, at margins usually several small bundles.

Inflorescences

The inflorescences are between the sheets, each inflorescence grows through the split petiole base of his support sheet. Only in Cryosophila nana he grows out the side of the uncleaved petiole. The inflorescences can be ascending, arching, or face down. The main axis of the inflorescence is 20-130 cm long with a diameter of 0.4 to 2.1 cm at the transition from the Peduncle to the inflorescence axis, only Cryosophila cookii it is thicker with up to 3.0 cm. The peduncle is between 10 and 80 cm long, the cover sheet 5 to 25 cm. On Peduncle there are two to ten bracts. These are 5-50 cm long and are broadly to narrowly oval. The inflorescence axis is between 5 and 70 cm long and thus takes between one-fifth and two-thirds of the total inflorescence length a. With the exception of Cryosophila cookii the inflorescences have 10 to 40 lateral axes of the first order. Usually the lowest side branches are even more branched twice, once in the middle and the top is not. The longest lateral branches of the first order are 1 to 20 cm long, and they are only Cryosophila stauracantha and Cryosophila warscewiczii longer than 7 cm. Each side branch first order sits in the shoulder of a high sheet. This is broadly oval to linear oval. The longest high leaves are 5-30 cm long.

The fruit stand is either open, so that the side branches of the first order are visible ( at Cryosophila stauracantha and Cryosophila warscewiczii ), or the fruits are so dense that the side branches are not visible (for all other species).

Flowers

The flowers are 2 to 6 mm long and 1.5 to 5 mm wide. They are individually on short stalks from 0.1 to 1.5 mm in length. The three ivory - white to cream-colored sepals are fused up to half of each other. The three petals are free and of the same color. The androecium consists of six stamens, whose flat, thin filaments, which are usually grown together over one to three quarters of their length. They are usually 2 to 3 mm long, the anthers from 1 to 2.5 mm. The stamp consists of three carpels. The ovary has a diameter of 0.2 to 1.4 mm, style and stigma are together 0.7 to 3.5 mm long.

The flowers are proterogyn: the scar are ready to receive, while the inflorescence is still in the bud stage. The scars dry up before the bracts of the inflorescence stalk open and before the anthers open. The pollen grains are monosulcat or trichotomosulcat (ie have a single or three-engine germ fold ). In the form of pollen grains is elliptical to triangular in polar, the surface of the reticulate exine is furrowed - reticulate or punctured.

The flowers are very uniform within the genus and offer unlike most Palm genera hardly features to distinguish the different species. The flowers are smaller in Cryosophila cookii and Cryosophial guagara usually greater than 4.8 mm, with the other species.

Fruit and seeds

Seeds have the same shape as the fruit. Only in Cryosophila williamsii they are very irregularly shaped. They are 0.7 to 2.7 cm long with a diameter from 0.7 to 2.3 cm, the surface is straw colored cream to.

Distribution, locations and hazard

The genus is native to Central America. The area extends north to Mexico in the south to the north-west Colombia. Most species are disjoint before in a linear sequence from north to south. Some species are extremely abundant locally endemic species.

All species of the genus grow in the understory of forests. Most grow in moist to wet lowland forests. Exception is Cryosophila nana, which grows in dry forests. Cryosophila kalbreyeri and Cryosophila stauracantha can also thrive on drier sites. The highest offices are located in approximately 1,000 meters above sea level, five species are calciphil, ie preferentially grow on limestone, with Cryosophila bartlettii and Cryosophila williamsii only occur on limestone cliffs. The remaining species - except Cryosophila nana - are calcifug, so avoid calcareous soils.

Evans called in 1995, five of the ten species as endangered ( threatened or endangered ): Cryosophila bartlettii, cookii, grayumii, kalbreyeri and C. williamsii. Cryosophila macrocarpa he described as very rare with an unknown degree of risk. Cause of the risk is mainly the loss of sites due to destruction of the rainforest. In his classification for the IUCN in 1998 he classified by the seven kinds mentioned three threat as low a ( Cryosophila guagara, Cryosophila kalbreyeri and Cryosophila nana ), Cryosophila bartlettii as endangered, two species as threatened with extinction ( Cryosophila cookii and Cryosophila grayumii ). Cryosophila williamsii is extinct in the wild.

System

The genus Cryosophila is placed in the subfamily Coryphoideae, Tribe Cryosophileae within the family Arecaceae.

Randall J. Evans accepted in 1995 in his monograph on the genus 10 species. These were taken over by Rafael Govaerts and John Dransfield in their World Checklist of Palms 2005.

• Cryosophila bartlettii
• Cryosophila cookii
• Cryosophila grayumii
• Cryosophila guagara
• Cryosophila kalbreyeri
• Cryosophila macrocarpa
• Cryosophila nana
• Cryosophila stauracantha
• Cryosophila warscewiczii
• Cryosophila williamsii

The cladistic analysis of morphological characters by Evans was following strict consensus tree:

Cryosophila warscewiczii

Cryosophila nana

Cryosophila grayumii

Cryosophila kalbreyeri

Cryosophila bartlettii

Cryosophila williamsii

Cryosophila guagara

Cryosophila cookii

Cryosophila macrocarpa

Cryosophila stauracantha

The name means Cryosophila cold -loving. The meaning is unknown, since all species are sensitive to cold.

History of Research

Cryosophila nana was described as the first kind, which today is counted to the genus, though initially placed in today pure Old World genera: Corypha (as Corypha nails HBK ) or Chamaerops (as Chamaerops mocini HBK ). Carl Ludwig Blume introduced in 1838 or 1839 to the genus Cryosophila to which he only Cryosophila nana counted. Wendland described the same way in 1869 under the name Acanthorrhiza aculeata in a new genre again, this has been recognized by Bartlett in 1935, just as that Kunth had described the same way twice. Bartlett described three new species in 1935, Allen 1953 two more. The key provision of the last two authors, however, did not allow unambiguous determination of the species. A comprehensive description of the genus features Moore published in 1972, which was essentially taken by Uhl and Dransfield 1987. The first monograph on the genus with a revision of the species published RJ Evans 1995.

Documents

• Randall J. Evans: Systematics of Cryosophila ( Palmae ). Systematic Botany Monographs, Volume 46, 1995, pp. 1-70. ( JSTOR )