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Issue: Vol. 762 No. 1: 12 Jun. 2026
Type: Article
Published: 2026-06-12
DOI: 10.11646/phytotaxa.762.1.3
Page range: 33-50
Abstract views: 0
PDF downloaded: 0

A revision of the mycoheterotrophic genus Epirixanthes (Polygalaceae) in Vietnam

Joint Vietnam-Russia Tropical Science and Technology Research Center; A.N. Severtsov Institute of Ecology and Evolution; Russian Academy of Sciences; 33; Leninsky avenue; 119071 Moscow; Russia; Department of Higher Plants; Faculty of Biology; M.V. Lomonosov Moscow State University; 1; 12; Leninskie Gory; 119234 Moscow; Russia
Joint Vietnam-Russia Tropical Science and Technology Research Center; A.N. Severtsov Institute of Ecology and Evolution; Russian Academy of Sciences; 33; Leninsky avenue; 119071 Moscow; Russia; Department of Higher Plants; Faculty of Biology; M.V. Lomonosov Moscow State University; 1; 12; Leninskie Gory; 119234 Moscow; Russia
Komarov Botanical Institute; Russian Academy of Sciences; 2; Prof. Popov street; 197022 St. Petersburg; Russia
Mientrung Institute for Scientific Research; Vietnam National Museum of Nature; Vietnam Academy of Science and Technology; 321; Huynh Thuc Khang street; Hue City; Vietnam
Joint Vietnam-Russia Tropical Science and Technology Research Center; A.N. Severtsov Institute of Ecology and Evolution; Russian Academy of Sciences; 33; Leninsky avenue; 119071 Moscow; Russia; Department of Higher Plants; Faculty of Biology; M.V. Lomonosov Moscow State University; 1; 12; Leninskie Gory; 119234 Moscow; Russia; Faculty of Biology; Shenzhen MSU-BIT University; No. 1; International University Park road; Dayun New Town; Longgang District; 518172 Shenzhen; China
Botanical Museum; Finnish Museum of Natural History; PO Box 7; FI-00014 University of Helsinki; Helsinki; Finland
Joint Vietnam-Russia Tropical Science and Technology Research Center; 63; Nguyen Van Huyen street; Nghia Do Ward; 122000 Hanoi; Vietnam
Joint Vietnam-Russia Tropical Science and Technology Research Center; A.N. Severtsov Institute of Ecology and Evolution; Russian Academy of Sciences; 33; Leninsky avenue; 119071 Moscow; Russia
Joint Vietnam-Russia Tropical Science and Technology Research Center; A.N. Severtsov Institute of Ecology and Evolution; Russian Academy of Sciences; 33; Leninsky avenue; 119071 Moscow; Russia
Department of Higher Plants; Faculty of Biology; M.V. Lomonosov Moscow State University; 1; 12; Leninskie Gory; 119234 Moscow; Russia; Laboratory of Plant Genomics; Vavilov Institute of General Genetics; Russian Academy of Sciences; 3; Gubkina street; 119991 Moscow; Russia
Eudicots achlorophyllous plants Eastern Indochina new national record nomenclature Salomonia tribe Polygaleae X-ray microtomography

Abstract

A taxonomic revision of Epirixanthes, the only mycoheterotrophic genus of Polygalaceae, is presented for Vietnam. Two species are recognized, of which E. elongata is known to be widely distributed across tropical Asia and E. kinabaluensis was considered endemic to Malesia prior to our study. Several nomenclatural inconsistencies are resolved for the names related to Epirixanthes. The original spelling of the generic name is confirmed as nomenclaturally correct because of being derived from conventional phonetic variants in Medieval Latin. Morphological descriptions of both Vietnamese species are significantly amended, reflecting novel data on the gross structure of their flowers and on intraspecific variation. For each species, the distinction from its most similar congener is summarized. Extensive illustrations of inflorescences and flowers of both species are provided; the inner structure of the intact flowers is illustrated with 3D images produced using X-ray microtomography.

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How to Cite

Nuraliev, M.S., Lyskov, D.F., Averyanov, L.V., Le, T.A., Kopylov-Guskov, Y.O., Sennikov, A.N., Dac, L.X., Kuznetsov, A.N., Kuznetsova, S.P. & Yudina, S.V. (2026) A revision of the mycoheterotrophic genus Epirixanthes (Polygalaceae) in Vietnam. Phytotaxa 762 (1): 33–50. https://doi.org/10.11646/phytotaxa.762.1.3