Hoya cutis-porcelana
| Hoya cutis-porcelana | ||||||||||||
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| Hoya cutis-porcelana | ||||||||||||
| W.Suarez , JRSahagun & Aurigue |
Hoya-cutis porcelana is a plant of the genus of wax flowers ( Hoya ) of the subfamily of asclepiadoideae (Asclepiadoideae).
features
Hoya cutis-porcelana is an epiphytic , climbing plant with twisting shoots. The shoots are very thin and flexible, some older shoots become lignified. The shoots have adhesive roots wherever the shoots rest on the substrate. The shoots are glabrous and measure 2 to 4 mm in diameter. The internodes are 8 to 11.4 mm long. The persistent, opposite leaves are petiolate, the stalks are often curved, measure 2 to 3 mm in diameter and are 1.1 to 2.5 cm long. The leaf blades are oblong-elliptical to broadly lanceolate, 5.5 to 12.1 cm long and 2.1 to 4.5 cm wide. They are leathery but elastic with a wedge-shaped base and a pointed apex. The lobed tip is curved downwards. The edges are also curved downwards, so that the undersides are concave and the upper sides are slightly convex. Fresh leaves have a glossy upper surface, which becomes duller with age. The underside is more matt and slightly lighter, even with fresh leaves. The pinnate leaf veins are lighter and more prominent. On each side of the midrib there are four to five secondary ribs connected by tertiary fine veins.
The hemispherical inflorescence has 8 to 12 flowers. The inflorescence stalk is, without rhachis, 1.5 to 5.8 cm long and measures 1 mm in diameter. It is persistent and faces a leaf. The buds are rounded with a papillary apex. The warty flower stalks are 1.2 cm long and 0.1 cm in diameter. The sepals do not reach the sinuses formed by the petals. They are warty on the outside, bare inside, and are 0.18 cm long and 0.12 cm wide at the base. The apex is blunt. The cream-colored corolla measures 15 mm in diameter or 17 mm when fully expanded. The corolla lobes are fused to about a third (of the total length) at the base. They are hairy on the inside and bald on the outside. The apex is pointed, the edges and the tip bent. The lobes are 6.3 mm long (or 6.4 mm when spread flat) and about 0.38 mm wide at the base. The pink secondary crown, red in the center, only slightly protrudes over the sinuses of the corolla lobes. The top of the corolla lobes is bare, sticky, and a little sunken. The inner process is pointed and rises almost vertically and over the center, the outer process is also pointed. The Pollinia are 350 µm long and 170 µm wide. The caudicles are 100 µm long and 30 µm thick. The corpusculum is 220 µm long and narrowed in the middle. The shoulder is 160 µm wide, the waist 80 µm and the hip 130 µm. The two horn-shaped appendages at the base are 30 µm long. The caudiculae start at the waist . The bald ovaries are pear-shaped and 1.8 mm long. The base is 0.6mm wide. Fruits and seeds are not known. The flowers smell sweet and sour.
Similar species
Hoya cutis-porcelana resembles Hoya camphorifolia Warb because of its leaves . and Hoya bicolensis Kloppenb., Siar & Cajano. The corolla is reminiscent of Hoya anulata Schltr.
Geographical distribution and habitat
The species is so far only two locations on the islands of Samar and Biliran known (Philippines). On Samar, the plant grew in a primary forest on limestone several kilometers from the coast, only 7 m above sea level. The species seems to prefer shady habitats.
Taxonomy
The taxon was described by Fernando B. Aurigue, Jorge R. Sahagun and Wally Suarez in 2013. The holotype is kept in the herbarium of the National Museum in Manila (Philippines) under the number 254882. The epithet means porcelain skin and refers to the porcelain-like top of the flowers.
The taxon is accepted as a valid taxon by the Plants of the World online database .
literature
- Fernando B. Aurigue, Jorge R. Sahagun, Wally Suarez: Hoya cutis-porcelana (Apocynaceae): A New Species from Samar and Biliran Islands, Philippines. Journal of Nature Studies. 12 (1): 12-17, 2013