Hoya gigas

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Hoya gigas
Flower and leaf (original illustration Schlechter 1913: Fig. 6 [1])

Flower and leaf (original illustration Schlechter 1913: Fig. 6)

Systematics
Order : Enzianartige (Gentianales)
Family : Dog poison family (Apocynaceae)
Subfamily : Silk plants (Asclepiadoideae)
Tribe : Marsdenieae
Genre : Wax flowers ( hoya )
Type : Hoya gigas
Scientific name
Hoya gigas
Schltr.

Hoya gigas is a plant of the genus of wax flowers ( Hoya ) of the subfamily of asclepiadoideae (Asclepiadoideae).

features

Hoya gigas is an epiphytic , climbing subshrub with thread-like, branched shoots. The sparsely leafed shoots are flexible, round in cross section and finely and softly tomentose. The rising or spreading, opposite leaves are stalked, the fleshy petioles, slightly runny on the upper side, are 1.5 to 2 cm long and finely tomentose. The leaf blades are oblong or elliptical-oblong, 9 to 11 cm long and 4.2 to 5.5 cm wide in the middle. The upper side is bald, the underside is very short tomentose. The base is rounded, the apex is long and pointed. The leaf nerve consists of the prominent midrib, which protrudes on the underside, and 5 to 7 very indistinct secondary ribs, which extend from the midrib on both sides.

The umbel-shaped inflorescence contains 3 to 7 flowers. The inflorescence stalks are 2.5 to 3 cm long and have very short tomentose hairs. They arise from the leaf nodes. The flower stalks are 2.3 to 3 cm long and also have very short tomentose hairs. The almost rounded sepals are somewhat uneven, 6 to 8 mm long or wide and have very short tomentose hair on the outside. The bell-shaped, reddish corolla is 8.2 cm in diameter when spread out. The petals are largely fused laterally ( sympetalie ). At the outer edge of the "bell" there are only five short wedge-shaped notches and small triangular tips that taper to a point. The corolla is sparsely hairy on the outside and minimally papilous on the inside. At the base it has a wreath of long, soft, straight hair. The edges of the tips are covered with cilia . The yellow secondary crown has a diameter of about 2 cm. The corolla lobes are rounded-ovoid. They measure about 7 mm from the tip of the inner process to the end of the outer process. The inner extension is short, beak-shaped, the outer extension is rounded. The tips are concave in the middle. The gynostegium is approximately 1.4 cm high. The pollinia are sickle-shaped without a cartilaginous outer edge. They narrow to the "caudiculae" (appendages) significantly. The caudiculae are relatively thick, very long and s-shaped, only slightly shorter than the pollinia. The corpusculum is rhombic and relatively large, the lower end is drawn out to a point. The caudiculae start above the widest point on the corpusculum. Below the widest point, there are two narrow, short cushions on the outside.

Similar Art

Hoya gigas is similar in shape, size and color to the flower Hoya lauterbachii . In Hoya lauterbachii , however, the corolla is arched more deeply, which is also densely covered with velvet-like hairs on the inside. The corolla by Hoya stenakei Simonsson & Rodda (2017) from Papua New Guinea is only slightly smaller (about 7 cm) and pastel pink .

Geographical distribution and habitat

The species occurs in Papua New Guinea in the Gomadjidji, on the banks of the Waria. It was worse when it was blooming in May 1909 on trees about 450 m above sea level.

Taxonomy

The taxon was described by Rudolf Schlechter in 1913 . The holotype is kept under the number Schlechter # 19389 in the herbarium of the Botanical Garden Berlin . The Plants of the World online database accepts the taxon as a valid species.

literature

Individual evidence

  1. ^ A b Rudolf Schlechter: The Asclepiadaceen of German New Guinea. Botanical Yearbooks for Systematics, Plant History and Plant Geography, 50: 81–164, 1913. Online at Biodiversity Heritage Library , pp. 136/37.
  2. ↑ Kew Science - Plants of the World online: Hoya gigas Schltr.