Dendrobium smillieae

Dendrobium smillieae is an epiphytic or lithophytic herb with crowded, ribbed, greenish or yellowish spindle-shaped pseudobulbs {{convert|0.3-1.0|m|ft|sigfig=1|abbr=on}} long and {{convert|20-30|mm|in|sigfig=1|abbr=on}} wide. The pseudobulbs have leaves during their first year, but are leafless at maturity. The leaves are bright green, thin, often twisted, {{convert|150-200|mm|in|sigfig=1|abbr=on}} long and {{convert|30-40|mm|in|sigfig=2|abbr=on}} wide. The flowers are arranged in crowded, bottlebrush-like groups {{convert|80-150|mm|in|sigfig=1|abbr=on}} long on the end of the pseudobulbs. The flowers are white, greenish, cream-coloured or pink, more or less tube-shaped and {{convert|20-25|mm|in|sigfig=2|abbr=on}} long. The sepals and petals are blunt, {{convert|7-10|mm|in|sigfig=2|abbr=on}} long and do not open widely. The labellum is about {{convert|16|mm|in|sigfig=1|abbr=on}} long, {{convert|3-4|mm|in|sigfig=1|abbr=on}} wide with a shiny, dark green tip. Flowering occurs from August to November.{{cite web |title=Dendrobium smillieae |url=http://www.orchidsnewguinea.com/orchid-information/species/speciescode/2621|publisher=Orchids of New Guinea |accessdate=30 November 2018}}{{cite web |author1=D.L.Jones |author2=T.Hopley |author3=S.M.Duffy |author1-link=David L. Jones (botanist) |year=2010 |access-date=28 May 2021 |url=http://www.canbr.gov.au/cpbr/cd-keys/RFKOrchids/key/rfkorchids/Media/Html/Coelandria_smillieae.htm |title=Factsheet - Coelandria smillieae |website=Australian Tropical Rainforest Orchids |publisher=Centre for Australian National Biodiversity Research (CANBR), Australian Government}}

A white variety is found in the Sepik swamps in New Guinea.Teoh, Eng-Soon. (2005) Orchids of Asia. New & Expanded Third Edition. Times Editions - Marshall Cavendish. {{ISBN|978-981-261-015-7}}. p. 124.

Dendrobium smillieae was first formally described in 1867 by Ferdinand von Mueller from a specimen collected near Rockingham Bay by John Dallachy. The description was published in Fragmenta phytographiae Australiae.{{cite web|title=Dendrobium smillieae|url= https://id.biodiversity.org.au/instance/apni/505805|publisher=APNI|accessdate=30 November 2018}} The specific epithet (smillieae) honours E.J. Smillie.{{cite book |last1=von Mueller |first1=Ferdinand |title=Fragmenta phytographiae Australiae |date=1867 |volume=v.6 1867-68 |publisher=Victorian Government Printer |location=Melbourne |page=94 |url=https://biodiversitylibrary.org/page/764832}}

The bottlebrush orchid is widespread and common, growing on trees and sometimes on rocks, in woodland, forest and rainforest margins. It prefers trees which are exposed to sunlight and commonly grows on trees such as Lophostemon suaveolens (swamp turpentine or swamp box) which have loose papery bark. The roots of the orchid penetrate below the bark and form large mats which are well protected beneath the bark. It is found in New Guinea, including on the Bismarck Archipelago, on the Aru Islands, on some Torres Strait Islands and on the Cape York Peninsula as far south as Townsville.Beasley, John (2006). Plants of Tropical North Queensland the Compact Guide. Footloose Publications. Kuranda, Qld., Australia. {{ISBN|1-876617-13-6}}. pp. 57, 73.

The flowers of this orchid produce nectar and are pollinated by the yellow honeyeater (Stomiopera flava) also known in Queensland as the canary honeyeater. The bird hovers in front of the flowers while feeding on the nectar.