Petrobium

{{Short description|Genus of flowering plants}}

{{Speciesbox

|image = MELLISS(1875) p399 - PLATE 42 - Pretobium Arboreum.jpg

|image_caption = Petrobium arboreum1875 illustration from page 399 of St. Helena: a physical, historical, and topographical description of the island ... The botanical plates from original drawings by Mrs. J. C. Melliss, by Melliss, John Charles. Original held and digitised by the British Library

|status = EN

|status_system = IUCN3.1

|status_ref = {{cite iucn |author=Lambdon, P.W. |author2=Ellick, S. |date=2016 |title=Petrobium arboreum |volume=2016 |page=e.T37597A67371334 |doi=10.2305/IUCN.UK.2016-1.RLTS.T37597A67371334.en |access-date=18 November 2021}}

|display_parents = 3

|genus = Petrobium

|parent_authority = R.Br. 1818 not Bong. 1838 (Melastomataceae)[http://www.tropicos.org/NameSearch.aspx?name=Petrobium&commonname= Tropicos, search for Petrobium]

|species = arboreum

|authority = (J.R.Forst. & G.Forst.) R.Br. ex Spreng.

|synonyms_ref =

|synonyms =

• Laxmannia J.R.Forst. & G.Forst.1775, rejected name, not R.Br. 1810 (Asparagaceae) nor Schreb. 1791 (Rutaceae) nor S.G.Gmel. ex Trin. 1818 (Rubiaceae)
• Drimyphyllum Burch. ex DC.
• [haretranthus Klatt
• [haretranthus ferrugineus Klatt
• [axmannia arborea J.R.Forst. & G.Forst.
• Drimyphyllum helenianum Burch. ex DC.

}}

Petrobium is a genus in the family Asteraceae.[https://www.biodiversitylibrary.org/page/758671#page/121/mode/1up Brown, Robert. 1818. Transactions of the Linnean Society of London 12(1): 113-114] description in Latin, commentary in English[http://www.tropicos.org/Name/40005578 Tropicos, Petrobium R. Br.]

The only known species is Petrobium arboreum, called Saint Helena whitewood. It is found in the tree-fern thicket at the top of the central ridge of island of Saint Helena in the South Atlantic Ocean. The plants are either female or hermaphrodite, i.e. the species is gynodioecious.[http://dixon.iplantcollaborative.org/CompositaeWeb/Default.aspx?Page=NameSearch&searchText=Petrobium&searchField=NameFull Flann, C (ed) 2009+ Global Compositae Checklist ] {{webarchive|url=https://archive.today/20141229002829/http://dixon.iplantcollaborative.org/CompositaeWeb/Default.aspx?Page=NameSearch&searchText=Petrobium&searchField=NameFull |date=2014-12-29 }}