Diuris byronensis

{{Short description|Species of orchid}}

{{Italic title}}

{{Speciesbox

| name = Byron Bay donkey orchid

| image = Diuris byronensis.jpg

| status = CR

| status_system = IUCN3.1

| status_ref = {{cite iucn |author=Romand-Monnier, F. |year=2013 |title=Diuris byronensis |volume=2013 |page=e.T44392384A44514172 |doi=10.2305/IUCN.UK.2013-1.RLTS.T44392384A44514172.en |access-date=6 April 2023}}

| image_caption =

| genus = Diuris

| species = byronensis

| authority = D.L.Jones{{cite web |title=Diuris byronensis |url=https://biodiversity.org.au/nsl/services/apc-format/display/179494 |publisher=Australian Plant Census |access-date= 6 April 2023}}

}}

Diuris byronensis, commonly known as the Byron Bay donkey orchid, is a species of orchid that is endemic to the Arakwal National Park in New South Wales. It has one or two grass-like leaves and up to five bright yellow flowers with blackish markings. It has a very limited distribution near Byron Bay.

Description

Diuris byronensis is a tuberous, perennial herb with one or two leaves {{convert|100-250|mm|in|sigfig=1|abbr=on}} long, {{convert|2-4|mm|in|sigfig=1|abbr=on}} wide and folded lengthwise. Between two and five bright yellow flowers with blackish markings, {{convert|20-30|mm|in|sigfig=1|abbr=on}} wide are borne on a flowering stem {{convert|100-300|mm|in|sigfig=1|abbr=on}} tall. The dorsal sepal is more or less erect, {{convert|9-12|mm|in|sigfig=1|abbr=on}} long and {{convert|6-7|mm|in|sigfig=1|abbr=on}} wide. The lateral sepals are {{convert|20-34|mm|in|sigfig=1|abbr=on}} long, {{convert|1.5-2|mm|in|sigfig=1|abbr=on}} wide and turned downwards. The petals are held horizontally, often turned backwards with an elliptic blade {{convert|9-13|mm|in|sigfig=1|abbr=on}} long and {{convert|5-8|mm|in|sigfig=1|abbr=on}} wide on a brown stalk {{convert|4-6|mm|in|sigfig=2|abbr=on}} long. The labellum is {{convert|10-15|mm|in|sigfig=1|abbr=on}} long and has three lobes. The centre lobe is egg-shaped, {{convert|9-12|mm|in|sigfig=1|abbr=on}} long and {{convert|6-8|mm|in|sigfig=1|abbr=on}} wide and the side lobes are {{convert|1.5-2.5|mm|in|sigfig=1|abbr=on}} long and less than {{convert|1|mm|in|sigfig=1|abbr=on}} wide. There are two ridge-shaped calli {{convert|3|mm|in|sigfig=1|abbr=on}} long at the base of the mid-line of the labellum. Flowering occurs in August and September.{{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=978-1877069123|page =121}}

Taxonomy and naming

Diuris byronensis was first formally described in 2003 by David Jones from a specimen collected near Byron Bay and the description was published in The Orchadian.{{cite web|title=Duiris byronensis|url= https://id.biodiversity.org.au/instance/apni/582430|publisher=APNI|accessdate=15 March 2018}}

Distribution and habitat

The Byron Bay donkey orchid is only known from a small part of the Arakwal National Park where it grows with sedges and grasses in a rare type of heath known as Byron Bay Dwarf Graminoid Clay Heath.{{cite web|title=Byron Bay Clay Heath Restoration Project|url=http://www.nrfabcon.org.au/projects/byron-bay-dwarf-graminoid-clay-heath-restoration-project|publisher=Northern Rivers Fire and Biodiversity Consortium|accessdate=15 March 2018}}

Conservation

Diuris byronensis is classed as "critically endangered" in the IUCN Red List of Threatened Species and as "endangered" under the New South Wales Biodiversity Conservation Act. The main threats to the species are its limited geographic range, loss of habitat and weed invasion. Projects are underway to protect the habitat of this orchid and other threatened species.

References