Hoya kanyakumariana

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Hoya kanyakumariana
Hoya kanyakumariana, inflorescence

Hoya kanyakumariana , inflorescence

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

Hoya kanyakumariana is a plant from the genus of wax flowers ( Hoya ) in the subfamily of asclepiadoideae (Asclepiadoideae). It is endemic to the Kanyakumari district in the Indian state of Tamil Nadu , near the southern tip of the Indian subcontinent.

features

Vegetative characteristics

Hoya kanyakumariana is a comparatively small, climbing, epiphytic , perennial herbaceous plant that grows slowly. With a diameter of about 2 millimeters in cross-section, the shoot axes are only 20 to 60 centimeters long and branched. The warty, gray shoot axes are initially downy and hairy and later bald. Adhesive roots can be present along the entire length of the stem axis.

The opposite arranged leaves are divided into a petiole and a leaf blade. With a length of 2 to 6 millimeters, the relatively short petiole has a diameter of up to 3 millimeters. The fleshy, slightly succulent leaf blades have a length of 1.5 to 3.3 centimeters and a width of 1.5 to 2.2 centimeters wide, obovate or heart-shaped with a rounded to slightly sunken upper end and it increases The width of the spread base gradually decreases. The bare leaf blades are light green with silver-colored speckles. The leaf margins are slightly wavy. The leaf veins are not visible.

Generative characteristics

With a diameter of 25 to 35 millimeters, the arched, umbel-shaped inflorescences contain up to 15 flowers (9 to 12 flowers, 9 to 15 flowers). The strong inflorescence shafts arise from the leaf axils and are up to 1.6 centimeters long. They are persistent, that is, the plant blooms from the same inflorescence shafts over and over again. They are round and downy hairy in cross section, older inflorescence shafts are pitted in the upper part. The sturdy flower stalks are up to 1.8 centimeters long and finely hairy. They each leave a scar on the inflorescence axis when they fall off. The bracts are very small.

The hermaphrodite flowers are zygomorphic and five-fold with a double flower envelope . The five bald sepals are egg-shaped with a length of about 1.5 millimeters and a width of about 1 millimeter. The whitish-light pink corolla is wheel-shaped with a diameter of 1 to 1.2 centimeters. The petals are fused about halfway ( sympetalie ). The inside dense downy hairy, outside bare corolla lobes are egg-shaped with a rounded upper end and rolled edges. The staminale secondary crown has a diameter of 5 to 6 millimeters and is cream-white with a purple central point. The tips of the secondary staminal crown are flat, the top is concave. The respective outer extension is pointed, as is the inner extension. The gynostegium has a short stalk. The pollinia are oblong-egg-shaped, about 500 µm long. The "retinaculum" is winged.

The flowers of the Hoya kanyakumariana remain open for about 3 to 5 days (five to six days) and have a slightly sweet, pleasant scent, especially in the evening. The flowers produce a lot of nectar , but it rarely drips from the flower. At the natural site, the flowering period extends from April to summer. It takes about 3 weeks from the beginning of the buds to the opening of the flower.

Occurrence

Hoya kanyakumariana has so far only been found in the lower Kothayar valley in the Kanyakumari district in the Indian state of Tamil Nadu at altitudes of about 600 meters. Cape Komorin (Kanyakumari or Kanya Kumari), an offshoot of the Western Ghats , is the southernmost point of the Indian subcontinent.

Taxonomy

The first description of Hoya kanyakumariana was made in 1979 by Ambrose Nathaniel Henry (botanical symbol: ANHenry) and Mangudi Srinivasan Swaminathan (botanical author abbreviation: Swamin.) In the 75th volume, number 2 of the Journal of the Bombay Natural History Society , S. 462. The for Volume 75, published in 1978, but No. 2 did not appear until 1979.

supporting documents

literature

  • Ambrose Nathaniel Henry, Mangudi Srinivasan Swaminathan: A new Hoya R.Br. (Asclepiadaceae) from South India. In: Journal of the Bombay Natural History Society , Volume 75, No. 2, Bombay / Mumbai, 1979, pp. 462-464.
  • Surisa Somadee, Jens Kühne: Hoya 200 different wax flowers. 96 p., Formosa-Verlag, Witten 2011 ISBN 978-3-934733-08-4 . (in the following, abbreviated from Somadee & Kühne, Hoya, with corresponding page number)
  • Anders Wennström, Katarina Stenman: The Genus Hoya - Species and Cultivation. 144 p., Botanova, Umeå 2008 ISBN 978-91-633-0477-4 . (in the following quoted from Wennström & Stenman, Genus Hoya with corresponding page number)

Individual evidence

  1. ↑ a b Somadee & Kühne, Hoya, p. 57.
  2. ↑ a b c Wennström & Stenmann, p. 74.
  3. ↑ a b c d e f g Hoya forum: Hoya kanyakumariana
  4. ↑ Hoya kanyakumariana at www.myhoyas.com
  5. ↑ Hoya kanyakumariana at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed March 21, 2015.

Web links

Commons : Hoya kanyakumariana  - collection of images, videos and audio files