Hoya of Sumatra, an updated checklist, three new species, and a new subspecies Author Rahayu, Sri Author Rodda, Michele text European Journal of Taxonomy 2019 2019-03-23 508 1 23 journal article 27816 10.5852/ejt.2019.508 6e176ff1-c6ce-429c-8b36-9d32c3cdc5c9 2118-9773 2612875 Hoya purpurascens Teijsm. & Binn. Natuurkundig Tijdschrift voor Nederlandsch Indië 25: 407 ( Teijsmann & Binnendijk 1863 ). Original citation “Sumatrae prov Lampong, Teijsmann” (type material not traced). Remarks This name is not recorded in Tropicos (http://www.tropicos.org, accessed on 24 Jul. 2018 ) and IPNI (http://www.ipni.org, accessed on 24 Jul. 2018 ) only records it as a nomen nudum ( Teijsmann & Binnendijk 1866 ). The species was validly published by Teijsmann & Binnendijk (1863) . Original material has been searched at BO, KRB, L, and U, but none has been found and it is possible that the species was described based on a live plant only.