Sphaerocoryne affinis
{{Short description|Species of flowering plants}}
{{Speciesbox
|image =
|image_caption =
|genus = Sphaerocoryne
|species = affinis
|authority = (Teijsm. & Binn.) Ridl.
|synonyms = {{Specieslist |hidden=yes
| Polyalthia affinis |Teijsm. & Binn.
| Dasymaschalon scandens |Merr.
| Melodorum aberrans |(Maingay ex Hook.f. & Thomson) J.Sinclair
| Mitrella aberrans |(Maingay ex Hook.f. & Thomson) Bân
| Mitrella mesnyi |Bân
| Monoon submitratum |Miq.
| Polyalthia aberrans |Maingay ex Hook.f. & Thomson
| Polyalthia submitrata |(Miq.) Ridl.
| Popowia aberrans |(Maingay ex Hook.f. & Thomson) Pierre ex Finet & Gagnep.
| Sphaerocoryne aberrans |(Maingay ex Hook.f. & Thomson) Ridl.
| Unona mesnyi |Pierre}}
}}
Sphaerocoryne affinis is a species of flowering plant in the soursop family, Annonaceae.
It is a liana (woody climbing plant) growing in lowland wet tropical forests at an elevation of up to {{convert|200|metres}}.{{cite journal |last1=Turner |first1=I. M. |title=Annonaceae of Borneo: a review of the climbing species |journal=The Gardens' Bulletin, Singapore |date=2012 |volume=64 |issue=2 |pages=371–479 |url=https://www.nparks.gov.sg/sbg/research/publications/gardens-bulletin-singapore/-/media/sbg/gardens-bulletin/gbs_64_02_y2012_v64_02/64_02_371_y2012_v64p2_gbs_pg_371.pdf}} It is distributed within west and central Malesia, and occurs at one locality in Southern Thailand, on Tarutao Island.{{cite journal |last1=Johnson |first1=David M. |last2=Bunchalee |first2=Pasakorn |last3=Chalermglin |first3=Piya |last4=Chantaranothai |first4=Pranom |last5=Leeratiwong |first5=Charan |last6=Murray |first6=Nancy A. |last7=Saunders |first7=Richard |last8=Sirichamorn |first8=Yotsawate |last9=Su |first9=Yvonne |last10=Sutthisaksopon |first10=Phanom |title=Additions to Annonaceae in the Flora of Thailand |journal=Thai Forest Bulletin (Botany) |date=28 July 2021 |volume=49 |issue=2 |pages=163–172 |doi=10.20531/tfb.2021.49.2.02|doi-access=free }}
Sphaerocoryne affinis is similar in appearance to S. lefevrei (a species with cultural significance in Cambodia and Thailand, where it is known as rumduol and lamduan, respectively), and some sources treat them as the same species. In Cambodia, the rumdoul has been referred to by the scientific name Mitrella mesnyi,{{cite web |title=Royal Decree on Designation of Animals and Plants as National Symbols of the Kingdom of Cambodia (unofficial translation) |url=http://www.forestry.gov.kh/Documents/ROYAL-DECREE-ENG.pdf |archive-url=https://web.archive.org/web/20060725154214/www.forestry.gov.kh/Documents/ROYAL-DECREE-ENG.pdf |archive-date=2006-07-25 |language=en |url-status=dead}} which most authorities regard as an illegitimate synonym of S. affinis, though this species does not occur in the country.