Eucalyptus helidonica
{{Short description|Species of eucalyptus}}
{{speciesbox
|name =
|image = Eucalyptus helidonica.jpg
|image_caption = Eucalyptus helidonica near Helidon
|status =
|status_system =
|genus = Eucalyptus
|species = helidonica
|authority = K.D.Hill{{cite web|title=Eucalyptus helidonica|url= https://biodiversity.org.au/nsl/services/apc-format/display/164121|publisher=Australian Plant Census|access-date=25 July 2019}}
}}
File:Eucalyptus helidonica bark.jpgFile:Eucalyptus helidonica buds.jpgFile:Eucalyptus helidonica fruit.jpg
Eucalyptus helidonica is a species of tree that is endemic to an area near Helidon in Queensland. It has rough, finely fibrous bark, lance-shaped or curved adult leaves that are paler on the lower surface, flower buds in groups of eleven or more, white flowers and shortened spherical or barrel-shaped fruit.
Description
Eucalyptus helidonica typically grows to a height of around {{convert|20|m|ft|0}} and forms a lignotuber. It has rough grey or grey-brown bark and finely fibrous bark over the trunk and the larger branches, smooth on the smaller branches. Young plants and coppice regrowth have sessile, linear to narrow lance-shaped leaves that are arranged in opposite pairs and paler on the lower surface. The juvenile leaves are {{cvt|60-135|mm}} long and {{cvt|7-18|mm}} wide. Adult leaves are lance-shaped or curved and dull green but paler on the lower surface, {{cvt|60-145|mm}} long and {{cvt|90-250|mm}} wide, tapering evenly to a petiole {{cvt|9-20|mm}} long. The flower buds are arranged in leaf axils in groups of eleven or more on an unbranched peduncle {{cvt|10-25|mm}} long, the individual buds on pedicels {{cvt|3-5|mm}} long. Mature buds are oval, {{cvt|4-5|mm}} long and about {{cvt|2|mm}} wide with a conical operculum. The flowers are white and the fruit is a woody shortened spherical to barrel-shaped capsule {{cvt|4-6|mm}} long and {{cvt|4-7|mm}} wide, with the valves near rim level or enclosed below it.{{cite web|url=https://apps.lucidcentral.org/euclid/text/entities/eucalyptus_helidonica.htm|title=Eucalyptus helidonica|access-date=1 June 2020|work=Euclid|publisher=CSIRO}}{{cite journal |last1=Hill |first1=Ken D. |title=A taxonomic revision of the White Mahoganies, Eucalyptus series Acmenoideae (Myrtaceae) |journal=Telopea |date=1999 |volume=8 |issue=2 |pages=225–226|doi=10.7751/telopea19993002 |doi-access=free }}
Taxonomy
Eucalyptus helidonica was first formally described by the botanist Kenneth Hill in 1999 in the journal Telopea. The specific epithet helidonica refers to the town in the centre of this species' distribution.{{cite web|title=Eucalyptus helidonica|url= https://id.biodiversity.org.au/instance/apni/562864 |publisher=APNI|access-date=25 July 2019}}
Eucalyptus helidonica is part of the white mahogany group as recognised by Ken Hill. Others in the group include E. acmenoides, E. mediocris, E. carnea, E. apothalassica, E. latisinensis, E. psammitica and E. umbra.{{cite web|url=https://www.anbg.gov.au/cpbr/cd-keys/euclid3/euclidsample/html/White_mahoganies.htm|title=More about White Mahoganies|access-date=28 October 2018|work=Euclid|publisher=CSIRO|archive-date=14 April 2019|archive-url=https://web.archive.org/web/20190414224938/https://www.anbg.gov.au/cpbr/cd-keys/euclid3/euclidsample/html/White_mahoganies.htm|url-status=dead}}
Distribution
This stringybark is endemic to a small area surrounding the town of Helidon to the west of Brisbane amongst the Great Dividing Range. It is found as a part of dry sclerophyll woodland communities where it is found on sandstone ridges and slopes growing in sandy soils.
Conservation status
This eucalypt is classified as "least concern" under the Queensland Government Nature Conservation Act 1992.{{cite web|url=http://wetlandinfo.ehp.qld.gov.au/wetlands/ecology/components/species/?eucalyptus-helidonica|title=Eucalyptus helidonica|access-date=8 November 2016|work=WetlandInfo|publisher=Queensland Government}}