{{Short description|Species of orchid}} {{Speciesbox | status = | status_system = EPBC | name = Bird's-mouth orchid | image = Waratah Track Orchid.JPG | image_caption = In [[Ku-ring-gai Chase National Park]], [[Australia]] | genus = Orthoceras (plant) | species = strictum | authority = [[R.Br.]]<ref name="APC">{{cite web |title=''Orthoceras strictum'' |url=https://biodiversity.org.au/nsl/services/apc-format/display/56871|publisher=Australian Plant Census |access-date=20 October 2025}}</ref> | synonyms_ref = <ref name="APC" /> | synonyms = ''Orthoceras'' sp. aff. ''strictum'' }}
''''' Orthoceras strictum''''', commonly known as the '''bird's-mouth orchid'''<ref name="RBGS" /> or '''horned orchid''',<ref name="RBGV" /> is a species of [[orchid]] [[Indigenous (ecology)|native]] to eastern and southern [[Australia]], [[New Zealand]] and [[New Caledonia]]. It has between two and five linear leaves and up to nine yellowish green, brownish or blackish flowers with two long, erect to spreading [[wikt:lateral|lateral]] [[sepal]]s.[[File:Orthoceras strictum green.jpg|thumb|225px|Yellowish green form in [[Cathedral Rock National Park]]]]
==Description== ''Orthoceras strictum'' is a terrestrial, [[Perennial plant|perennial]], [[deciduous]], [[Herbaceous plant|herb]] with an underground [[tuber]] and a tuft of between two and five linear to thread-like, grass-like leaves, {{convert|150-300|mm|in|sigfig=1|abbr=on}} long and {{convert|2-3|mm|in|sigfig=1|abbr=on}} wide. Up to nine flowers {{convert|8-10|mm|in|sigfig=1|abbr=on}} wide are borne on a rigid flowering stem {{convert|300-600|mm|in|sigfig=1|abbr=on}} tall. Flower colour varies from blackish, brownish, maroon to yellowish green. The dorsal sepal is egg-shaped and forms a hood over the rest of the flower, {{convert|9-12|mm|in|sigfig=1|abbr=on}} long and {{convert|8-10|mm|in|sigfig=1|abbr=on}} wide. The lateral sepals are linear, horn-like, {{convert|20-25|mm|in|sigfig=1|abbr=on}} long, about {{convert|1|mm|in|sigfig=1|abbr=on}} wide and erect, spreading or curved. The [[petal]]s are oblong, {{convert|8-10|mm|in|sigfig=1|abbr=on}} long, about {{convert|3|mm|in|sigfig=1|abbr=on}} wide and hidden inside the dorsal sepal. The [[Labellum (botany)|labellum]] is {{convert|6-10|mm|in|sigfig=1|abbr=on}} long and has three lobes. The middle lobe is elliptic to egg-shaped, {{convert|6-7|mm|in|sigfig=1|abbr=on}} long, {{convert|5-6|mm|in|sigfig=2|abbr=on}} wide and the side lobes are {{convert|5-6|mm|in|sigfig=2|abbr=on}} long, about {{convert|1.5|mm|in|sigfig=1|abbr=on}} wide. There is a pyramid-shaped [[Labellum (botany)|callus]] near the base of the labellum. Flowering occurs from November to February.<ref name="RBGS">{{cite web|last1=Bernhardt|first1=Peter|title=''Orthoceras strictum''|url=http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Orthoceras~strictum|publisher=Royal Botanic Garden Sydney|accessdate=17 March 2018}}</ref><ref name="RBGV">{{cite web|last1=Ohlsen|first1=Daniel|title=''Orthoceras strictum''|url=https://vicflora.rbg.vic.gov.au/flora/taxon/6464c337-dcff-40c7-ae8a-aaf6ef259587|publisher=Royal Botanic Gardens Victoria|accessdate=17 March 2018}}</ref><ref name="Jones">{{cite book|last1=Jones|first1=David L.|title=A complete guide to native orchids of Australia including the island territories|date=2006|publisher=New Holland|location=Frenchs Forest, N.S.W.|isbn=1877069124|page =283}}</ref>
==Taxonomy and naming== ''Orthoceras strictum'' was first formally described in 1810 by [[Robert Brown (botanist, born 1773)|Robert Brown]] and the description was published in his book ''[[Prodromus Florae Novae Hollandiae et Insulae Van Diemen]]''.<ref name=APNI>{{cite web|title=''Orthoceras strictum''|url= https://id.biodiversity.org.au/instance/apni/459721|publisher=APNI|accessdate=17 March 2018}}</ref><ref name="R.Br.">{{cite book|last1=Brown|first1=Robert|title=Prodromus Florae Novae Hollandiae et Insulae Van Diemen|date=1810|location=London|pages=317–318|url=https://www.biodiversitylibrary.org/item/21771#page/186/mode/1up|accessdate=17 March 2018}}</ref> The [[Genus|generic]] name (''Orthoceras'') is derived from the [[Ancient Greek]] words ''orthos'' meaning "straight"<ref name="RWB">{{cite book|last1=Brown|first1=Roland Wilbur|title=The Composition of Scientific Words|date=1956|publisher=Smithsonian Institution Press|location=Washington, D.C.}}</ref>{{rp|578}} and ''keras, keratos'' meaning "horn,<ref name="RWB" />{{rp|422}} which alludes to the upright lateral sepals.<ref>Les Robinson - Field Guide to the Native Plants of Sydney, {{ISBN|978-0-7318-1211-0}} page 251</ref> The [[Botanical nomenclature|specific epithet]] (''strictum'') is a [[Latin]] word meaning "straight" or "tight".<ref name="RWB" />{{rp|760}}
==Distribution and habitat== The bird's-mouth orchid is widespread but uncommon and occurs in [[New South Wales]], [[Queensland]], [[South Australia]], [[Tasmania]], [[Victoria (Australia)|Victoria]] and New Caledonia. It grows in a wide range of habitats from grassy forest to heath. The differences between this species and ''[[Orthoceras novae-zeelandiae]]'' from New Zealand are "very slight and dubious".<ref name="NZPCN">{{cite web|title=''Orthoceras novae-zeelandiae''|url=http://www.nzpcn.org.nz/flora_details.aspx?ID=1070|publisher=New Zealand Plant Conservation Network|accessdate=17 March 2018}}</ref>
==Conservation== ''Orthoceras strictum'' is listed in Tasmania as "rare" under the Tasmanian Government ''[[Threatened Species Protection Act 1995]]''.<ref name="dpipwe">{{cite web|title=''Orthoceras strictum'' - horned orchid|url=https://www.naturalvaluesatlas.tas.gov.au/downloadattachment?id=14223|publisher=Tasmanian Government Department of Primary Industries, Parks, Water and Environment|accessdate=17 March 2018}}</ref>
== References == {{Reflist}}
== External links == * {{Commons-inline}}
{{Taxonbar|from=Q3014832}}
[[Category:Diuridinae]] [[Category:Orchids of Oceania]] [[Category:Orchids of New South Wales]] [[Category:Orchids of Victoria (state)]] [[Category:Orchids of South Australia]] [[Category:Orchids of Tasmania]] [[Category:Orchids of Queensland]] [[Category:Orchids of New Zealand]] [[Category:Orchids of New Guinea]] [[Category:Orchids of New Caledonia]] [[Category:Plants described in 1810]]