Angraecum Names and Synonyms: Understanding Orchid Taxonomy

Overview of Angraecum taxonomy

The orchid genus Angraecum was first published by Bory in 1804 in Voyage aux îles d’Afrique and is currently accepted by major taxonomic databases such as Kew’s Plants of the World Online (POWO) and World Flora Online (WFO) ^[1][5]. The genus belongs to the tribe Vandeae, subtribe Angraecinae, and its native range extends from tropical Africa to Sri Lanka, with a concentration of diversity in Madagascar.

Why orchid names change

Botanical nomenclature follows the International Code of Nomenclature (ICN). A name may be replaced or added for several reasons:

• Homotypic (nomenclatural) synonym: a different name based on the same type specimen. The later name is not the accepted one, but it remains linked to the original description.
• Heterotypic (taxonomic) synonym: a name based on a different type that later research shows belongs to the same species.
• Generic synonymy: entire genera are merged when phylogenetic or morphological evidence shows they are not distinct.

Understanding these categories helps growers interpret labels and avoid confusion when older horticultural literature uses outdated names.

Generic synonyms of Angraecum

Historical taxonomists described several genera that are now considered synonymous with Angraecum. Major generic synonyms listed by World Flora Online and other databases include:

• Aerobion Kaempf. ex Spreng.
• Angorchis Thouars (illegitimate)
• Macroplectrum Pfitzer
• Bonniera Cordem.
• Lepervenchea Cordem.
• Pectinaria Cordem.
• Ctenorchis K.Schum.
• Monixus Finet
• Dolabrifolia (Pfitzer) Szlach. & Romowicz

These synonyms are recorded in the WFO snapshot ^[5] and are reiterated on specialist sites such as African Orchids and GRIN‑Global ^[6][10]. When a horticultural label uses one of these historic names, the plant is still a member of the accepted genus Angraecum.

Species‑level synonymy – illustrative examples

Individual species often have long synonymic histories. Two well‑documented examples illustrate the pattern.

Angraecum leonis

First published as Angraecum leonis by Reichenbach f. and later transferred by André (1885), this species currently bears several homotypic synonyms, including Mystacidium leonis, Macroplectrum leonis, and Humblotiangraecum leonis ^[2]. Heterotypic synonyms such as Aeranthes leonii also appear in older literature.

Angraecum distichum

Described by Lindley in 1835, Angraecum distichum has nine recorded synonyms. Homotypic synonyms include Aeranthes disticha, Dolabrifolia disticha, and Macroplectrum distichum ^[3]. Heterotypic synonyms such as Angraecum imbricatum have been rejected as illegitimate homonyms.

These examples show that synonymy is common and that the accepted name may differ from the name found on older herbarium sheets or in legacy horticultural catalogs.

Sectional classification within Angraecum

Garay’s 1973 monograph divided the genus into 19 sections based on floral morphology and vegetative characters. This framework remains the backbone of most modern treatments and is reproduced on the American Orchid Society page ^[4]. Some of the sections include:

• section Acaulia
• section Afrangraecum
• section Arachnangraecum
• section Filangis
• section Hadrangis
• section Humblotiangraecum
• section Lemurangis
• section Pectinaria

Recent molecular phylogenies, such as the Angraecum‑wide analysis published in PLOS ONE (2017) and the doctoral dissertation by Verlynde (2025), confirm the monophyly of the genus but suggest that some traditional sections are not strictly monophyletic ^[8][12]. As a result, taxonomists are proposing revised sectional limits and, in a few cases, new combinations (e.g., the 2020 Kew Bulletin paper describing three new species and making two nomenclatural changes ^[7]).

How to use taxonomic resources

For accurate naming, consult up‑to‑date databases:

• Plants of the World Online (POWO): provides the accepted name, author citation, and distribution.
• World Flora Online (WFO): lists synonyms and the taxonomic backbone used by many institutions.
• International Plant Names Index (IPNI): records the original publication details of each name.
• GRIN‑Global: offers a curated list of generic synonyms for Angraecinae.

When a label shows a name that appears in the synonym list of any of these resources, treat the plant as an Angraecum species and use the accepted name for communication, trade, and conservation reporting.

Practical implications for growers and collectors

Understanding synonymy helps avoid duplicate purchases and ensures compliance with CITES regulations, which list species under their accepted names. If a nursery advertises Macroplectrum leonis, the plant is legally the same as Angraecum leonis. Recording the accepted name on a collection database also facilitates data sharing with botanists and conservationists.

Finally, because taxonomic revisions can change species limits, keep an eye on recent publications (e.g., Kew Bulletin 2020, PLOS ONE 2017) and update labels accordingly.