Diuris decrementum
{{Short description|Species of orchid}}
{{Italic title}}
{{Speciesbox
| name = Common bee orchid
| image = Diuris decrementa.jpg
| image_caption = Diuris decrementum growing in the Orchid Conservation Reserve near Tenterden
| genus = Diuris
| species = decrementum
| authority = D.L.Jones & C.J.French{{cite web|title=Diuris decrementum|url= https://biodiversity.org.au/nsl/services/apc-format/display/235897|publisher=Australian Plant Census|access-date=26 June 2023}}
| synonyms =
}}
Diuris decrementum, commonly called the common bee orchid,{{cite book|last1=Brown|first1=Andrew|last2=Dixon|first2=Kingsley|last3=French|first3=Christopher|last4=Brockman|first4=Garry|title=Field guide to the orchids of Western Australia : the definitive guide to the native orchids of Western Australia|date=2013|publisher=Simon Nevill Publications|isbn=9780980348149|page=223}} is a species of orchid which is endemic to the south-west of Western Australia. It is similar to the bee orchid (Diuris laxiflora) but its flowers are smaller and on a shorter flowering stem.
Description
Diuris decrementum is a tuberous, perennial herb, usually growing to a height of {{convert|80-300|mm|in|sigfig=1|abbr=on}} with two to five leaves emerging at the base, each {{convert|50-120|mm|in|sigfig=1|abbr=on}} long and {{convert|1-2|mm|in|sigfig=1|abbr=on}} wide. There are up to three yellow flowers with brown blotches, {{convert|8-12|mm|in|sigfig=1|abbr=on}} wide. The flowers have broad, ear-like petals, an erect, tapering dorsal sepal and narrow, forward-projecting lateral sepals. The labellum has three lobes, the lateral ones small and spreading, and the middle lobe elongated with a raised mid-line. Flowering occurs from late August to early November.{{cite journal |last1=Jones |first1=David L. |last2=French |first2=Christopher J. |title=The characterisation of Diuris laxiflora Lindl. and the description of four new allied species from Western Australia |journal=Australian Orchid Review |date=2013 |volume=78 |issue=1 |pages=30–33 |url=https://www.biodiversitylibrary.org/item/310584#page/32/mode/1up |access-date=26 June 2023}}
Taxonomy and naming
Diuris decrementum was first formally described in 2013 by David Jones and Christopher French and the description was published in Australian Orchid Review.{{cite web|title=Diuris decrementum|url= https://id.biodiversity.org.au/instance/apni/761666 |publisher=APNI|accessdate=11 October 2017}} The specific epithet (decrementum) is derived from the Latin word decrementum meaning "lessening"{{cite book|last1=Brown|first1=Roland Wilbur|title=The Composition of Scientific Words|date=1956|publisher=Smithsonian Institution Press|location=Washington, D.C.|page =470}} referring to the small flowers and shorter flowering stem of this species.
Distribution and habitat
The common bee orchid occurs from near Perth to the east of Esperance where it grows in a range of habitats from woodlands to soil pockets on granite outcrops.{{FloraBase|name=Diuris decrementum |id=50726}}
Conservation
Diuris decrementum is classified as "not threatened" by the Western Australian Government Department of Parks and Wildlife.