Rauhocereus
Rauhocereus riosaniensis
Rauhocereus riosaniensis is the only species of the monotypic genus Rauhocereus in the cactus family ( Cactaceae ). The botanical name of the genus honors the German botanist and cactus specialists Werner Rauh. The epithet refers to the type locality of the type, the valley of the river Sana.
Description
The mostly shrubby, usually branching from the base Rauhocereus riosaniensis often forms thickets up to 4 meters in height. The upright, columnar shoots are bluish- green and have a diameter of 8 to 15 centimeters. The 5 to 6 ribs are dissolved in many warts. From the woolly areoles spring 2-8 strong, to 5 -inch-long thorns. The lower ones are initially reddish, the upper yellowish. Later, all are grayish - white.
The bell-shaped flowers appear near the shoot tip. They open at night, 8 to 10 inches long and have a diameter of up to 5 centimeters. The flower cup and the flower tube are covered with small scales and krausene brown hair.
The red, fleshy fruits are ovoid with a perennial flowers rest. They contain small, ovoid, shiny black seeds.
Systematics and distribution
Rauhocereus riosaniensis is widespread in northern Peru. The first description of the genus and its single species was carried out in 1957 by Curt Backeberg. The genus is closely related to Browningia.
There are two subspecies:
- Rauhocereus riosaniensis subsp. riosaniensis
- Rauhocereus riosaniensis subsp. jaenensis