Vanilla polylepis
Vanilla polylepis is a plant of the genus Vanilla ( Vanilla ) in the orchid family ( Orchidaceae). It grows as a climber in tropical Africa.
Description
Vanilla polylepis is an evergreen climber, reached the six to nine meters in length. The sprout reaches up to two inches in diameter and is longitudinally striate. The leaves are oval to lanceolate, rounded at the base and very short-stalked, the front moved out long pointed ending. They are six to 21 ( to 24) cm long and 2.5 to eight inches wide.
The heyday of Vanilla polylepis is in November. The unbranched inflorescence is up to seven inches long, it bears 20 to 30 flowers that open successively and slightly scented with vanilla. The bracts are oval to triangular, acute, 0.6 to 0.7 inches tall. Pedicel and ovary together measure four to six inches. The flowers are white or greenish white, the lip is yellowish at the base and has a reddish drawing on the front (these may be absent ). Sepals and petals are lanceolate with the widest point above the middle, they end pointed. The dorsal sepal measures 3.5 to six inches long with 0.9 inches wide, the lateral sepals are slightly wider. The petals are keeled with one to 1.5 centimeters or slightly wider on the outside, they end up in a small patch tip. The lip is 4.5 to six inches long and three inches wide, it is unclear three-lobed, the front edge is wavy. On the lip up to twelve transverse rows are backward -looking scales; the front and end are linear unbranched or slightly toothed, the middle are oval to oblong and comb- shaped, the rear are covered with fine papillae. The column is three to 4.5 inches long, it has grown to two-thirds of its length with the lip. The cylindrical capsule fruit is up to 15 inches long with 1.5 inches in diameter. Along the fruit run two distinct grooves.
Dissemination
Vanilla polylepis is found in southern Africa: it was found in the countries of Angola, Malawi, Kenya, Congo, Zambia, Zimbabwe and Tanzania. It prefers to grow in well-supplied with water bodies, such as in wooded valleys and ravines, along streams, in gallery forests or on the edge of humid forests. This orchid grows at altitudes from 1200 to 1650 meters.
Systematics and botanical history
Vanilla polylepis in 1951 described by Summerhayes first time. The name polylepis refers to the various occurring on the lip scales. Summerhayes compared them mainly with Vanilla imperialis, but also with Vanilla and Vanilla africana ramosa. According Portères them apart from Vanilla imperialis is different, but it underlines the resemblance to Vanilla africana.
Within the genus Vanilla Vanilla polylepis, is classified in the subgenus Xanata and there in the section Thetya that contains all kinds of Paläotropis. See Soto Arenas and Cribb as Summerhayes Vanilla imperialis as next of kin, further Vanilla and Vanilla grandifolia ochyrae.