Hoya crassicaulis
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| Hoya crassicaulis | ||||||||||||
| Elmer ex Kloppenb. |
Hoya crassicaulis is a plant of the genus of wax flowers ( Hoya ) of the subfamily of asclepiadoideae (Asclepiadoideae).
features
The epiphytically growing, twisting plant has round, bare shoots with a maximum diameter of 5 mm in cross section. They are heavily branched, yellowish brown in color and slightly woody. The leaves consist of 1.5 to 5 cm long, thick, fleshy, bare stems with a longitudinal groove on the underside. The leaf blades are elliptical to oblong-elliptical in shape and reach a length of 73 to 147 millimeters with a width of 32 to 57 millimeters. They are leathery and bare, the top is very shiny. The base is broadly wedge-shaped, rounded or weakly heart-shaped. The apex is strongly bent back, the edge often slightly rolled up.
The spherical inflorescence has a comparatively very high number of flowers with 60 to 125 flowers. The ocher-brown inflorescence stalk is ascending and up to 5 cm long. It is glandular or covered with tiny papillae. The pale yellowish brown flower stalks are thread-shaped and 1.5 to 2.5 cm long. The narrow, elongated sepals are up to 1.5 mm long and taper to a point. They are colored reddish brown towards the tips and are bald or weakly ciliate on the outside. The deep yellow colored corolla has a diameter of about one centimeter. The bald tips of the petals are rhombic-ovate and pointed; they are strongly bent back and reddish in color. The flat, whitish secondary crown measures 4 mm in diameter and is 2 mm high. The tips of the staminal corolla are ovate-elongated. The outer extension is pointed, the inner extension also pointed, but with a weak keel on top.
The paired fruits are 9 to 12 cm long and 0.4 cm in diameter. The flat, pale brown seeds are 3 to 5 mm long and have dirty white hair. The flowers smell sharp, spicy.
Geographical distribution and habitat
Hoya crassicaulis occurs on the islands of Luzon and Panay (Philippines) (Kloppenburg). Elmer found the holotype at 250 feet (76 meters) above sea level. After Co's Digital Flora of the Philippines should Hoya crassicaulis but endemic to be of Luzon.
Taxonomy
The taxon was first published in 1938 by Adolph Daniel Edward Elmer. However, its description did not conform to the International Code of Nomenclature for Algae, Fungi and Plants and was therefore invalid. Dale Kloppenburg validated the taxon in 1995. The type location is on the island of Luzon. In 1986 Christine M. Burton put the illegitimate taxon Hoya crassicaulis in the synonym of Hoya incrassata . However, later authors have not followed this synonymization. Hoffmann et al. list Hoya crassicaulis as a valid taxon, as does Siar et al. and Villareal & Buot. Also Co's Digital Flora of the Philippines holds both types of valid taxa.
The holotype and Elmer's original material is kept at the Research Center for Biology in Cibinong, Indonesia # 14440 1915 Elmer and in Berkeley, California (UC, 2 / A).
According to Kloppenburg (2016), the species can be divided into two subspecies;
- Hoya crassicaulis subsp. capazensis Kloppenb., Panay, Philippines, the subspecies is distinguished by the pollinia, which have slightly different proportions than the nominate subspecies.
- Hoya crassicaulis subsp. crassicalis Elmer ex Kloppenb.
literature
- Focke Albers, Ulli Meve (Hrsg.): Succulent lexicon Volume 3 Asclepiadaceae (silk plants) . Ulmer, Stuttgart 2002, ISBN 3-8001-3982-0 (p. 149/50).
- Dale Kloppenburg and Ann Wayman: The World of Hoyas - a pictorial guide. A revised version. 248 pp., Orca Publishing Company, Central Point, Oregon 2007, ISBN 0-9630489-4-5 (pp. 64/5)
- Anders Wennström and Katarina Stenman: The Genus Hoya - Species and Cultivation. 144 p., Botanova, Umeå 2008 ISBN 978-91-633-0477-4 (p. 30)
Individual evidence
- ↑ a b Angela Marie M. Villareal, Inocencio E. Buot: Leaf Architecture of Hoya incrassata Warb. And Hoya crassicaulis Elmer x Kloppenb. (Apocynaceae): Taxonomic Identification and Conservation Concerns. International Journal of Ecology and Conservation, 15: 203-213, 2015. Research Gate
- ^ A b Co's Digital Flora of the Philippines by Leonardo L. Co Digital Flora of the Philippines
- ↑ a b Dale Kloppenburg: Fraterna, 1995 (3): 10-13, 1995 Online at Biodiversity Heritage Library .
- ↑ Christine M. Burton: H. incrassata Warburg (syn. H. crassicaulis Elmer). The Hoyan, 7 (4): p. 90, 1986
- Jump up ↑ Simeona (Monina) V. Siar, JA Dalu, CD Roldan, MC Redondo, MGQ Diaz, Jennelyn M. Carandang: Chromosomal Characteristics and Behavior of Four Philippine Endemic Hoyas: Hoya crassicaulis Elmer ex Kloppenburg, H. merrillii Schlechter, H. mcgregorfi Schlechter and H. pubicalyx Merrill. Philippine Journal of Crop Science, 36 (3): 65-69, 2011 ISSN 0115-463X
- ↑ Robert Dale Kloppenburg: Hoya crassicaulis subsp. capazensis Kloppenburg 2016. Hoya New, 5 (3): 10, 2016 Online at Biodiversity Heritage Library