Hibiscadelphus crucibracteatus

Hibiscadelphus crucibracteatus ( Hawaiian name: "Lava Hau kuahiwi " ) is an extinct species of the genus Hibiscadelphus within the family (Malvaceae ). He was endemic to the Hawaiian island of Lanai.

Description

Hibiscadelphus crucibracteatus was a deciduous tree, which reached a height of six meters. The trunk had a diameter of 16 centimeters. The leaves were five to fourteen inches long and unlobed. The leaf blade was ovate to broadly ovate. The top was substantially smooth. On the underside of the leaves stellate tufts of hair in the nerve axils had. The ganzrandige leaf margin was seven to elfzähnig and the leaf base open heart-shaped. The petioles were 1.5 to 5 inches long.

The flowers were single standing. The flower stems were 2 to 3.5 inches long. The four to five green, smooth, spatulate and slightly fused at the base of sepals were 20 to 30 mm long, 3-7 mm wide and showed a protruding midrib. The petals were dark purple, veined and unobtrusively between 5 and 6.5 cm long. The Columna was 4.2 to 4.9 inches long.

The capsule fruits were woody, almost spherical, five -angled, projecting, and approximately 2.3 to 2.7 cm long. The mesocarp was strongly developed and reticulate. There were ten endocarp layers. The seeds were hairy five to seven millimeters long and dull greyish white.

Status

In 1981, on a dry, windward facing slopes of Puhielelū Ridge discovered on Lanai at an altitude of 750 m above sea level, a single tree that went down in 1985. Efforts of the botanist Robert W. Hobdy to save this tree by seedlings were unsuccessful. The exact reason for the extinction of the species is not known, but probably the destruction of the humid forests on Lanai by Axishirsche and the displacement of endemic vegetation by invasive plants have played a major role.