Heft 4 · 2011 OrchideenJournal A New Dendrochilum Species from the Philippines Jim Cootes

Abstract: A new Dendrochilum spe- V-shaped channel for the upper three- Comparison: Dendrochilum tiongia- cies from section Acoridium, Den- quarters or more; overall 25 cm long num is related to Dendrochilum tenel- drochilum tiongianum Cootes, by 1.2 mm in diameter; apex acute. lum but differs in the stiff, upright ha- which is allied to Dendrochilum te- Infl orescences: appear with the new bit of the foliage which is also larger in nellum (Nees & Meyen) Ames, is he- growth; peduncle hair-like, becoming diameter (1.2 mm in Dchlm. tiongianum re, described as new. detached from the channel near the when compared to .75 mm in Dchlm. centre of the ; bearing up to 20 op- tenellum); the hair-like peduncle of Over the past 20 years the Den- posite blooms, which open widely, ab- Dchlm. tiongianum separates from the drochilum has gained a lot of interest out 2 mm in diameter. Floral are V-shaped leaf channel near the midd- in orchid collections. The main reason very small, enclosing pedicel and ova- le of the leaf. In Dchlm. tenellum the- for this is the fact that a specimen-si- ry. colour: sepals and petals re is no such separation between the zed can be grown in a relative- are translucent white, labellum is pale leaf and the peduncle. The fl owers of ly small pot, and the fl oral display, in orange. Dorsal sepal: ovate, apex acu- Dchlm. tiongianum are considerably season, is usually quite stunning. te, 1.5 mm long by .75 mm wide. Petals: smaller (2 mm) than those of Dchlm. te- During the year 2001, I was in the Phil- broadly ovate, apex acute, 2 mm long nellum (3 mm.) ippines, with the view of bringing back by 1 mm wide. Lateral sepals: ovate, Etymology: Named in honour of Dr. a number of orchid species, upon my apex acute, slightly ridged, 2 mm long George Tiong, close friend of the aut- return to Australia. were du- by .8 mm wide. Labellum: three lobed; hor. ly purchased from numerous sources, side lobes falcate and do not pass the and brought back to Australia. midlobe; midlobe square, apex obtu- Acknowledgement: Thanks to Wally Several years later, the plants that se. Pedicel and Ovary: tapering, 1 mm Suarez, Philippines, for the Latin dia- survived the quarantine period, began long. gnosis and Gary Yong Gee for the use to fl ower. The majority were as label- of his image of the plant habit. led, but as usual there were a couple Habitat and Distribution: Dendrochi- of specimens that could not be iden- lum tiongianum is endemic to the Phi- References tifi ed. Dendrochilum tiongianum Co- lippines, and according to the vendor, otes was one of these. came from the mountains of Nueva Pedersen, H.Æ. (1997): The genus The blooming habit, of Dendrochilum Vizcaya, where it grows as an epiphyte Dendrochilum () in the tiongianum, was observed for a num- on the mossy trunks and branches of Philippines – a taxonomic revision. ber of years, and when the untidy ha- trees at about 1,300 metres. Opera Botanica Number 131. bit of the infl orescences remained constant I felt assured that the species Foto / photo: © G. Y. Gee represented an undescribed entity.

Dendrochilum tiongianum Cootes sp. nov. Affi nis Dendrochilo tenello (Nees & Meyen) Ames, sed folia applanatus, non teretia, rigido et erecto absque ullus arcuatus; labello laterilobo fal- cato, non midlobo longitudine trans- iens; pedunculi cadens a canalis fo- lia, infl orescentio ita inordinatim aspectu differentia; differt.

Typus: Cootes 2011/01 cult. River- wood. Holotype: NSW884481 Growth habit: upright, sympodial, epi- phytic herb. Roots: fl eshy; branching. Pseudobulbs: clustered on a short rhi- zome; slightly tapering to 1 cm long by 1.5 mm in diameter; surrounded by persistent sheath. : upright; stiff; not arching; fully terete basally;

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