Introduction

Mycoheterotrophic plant species (MHP, Leake 1994) lack chlorophyll and depend on their mycorrhizal fungus for carbon and nutrient supply. MHP were first counted by Johow (1889), who estimated 160 species of “achlorophyllous humus plants” in 43 genera and 5 families. Schmucker (1959) already counted 352 “holosaprophytic” species in 48 genera and 6 families. Furman and Trappe (1971) referred to “roughly 400 species”, 50 genera and 7 families. In an review on MHPs (Leake 1994) lists 417 MHP species in 87 genera and 11 families. My own preliminary reassessment of Leake's list in 2008 resulted in 438 species/84 genera/10 families, but was just a rough estimate. The most recent assessment is of Merckx (2013) in his introducing chapter to the first book exclusively dedicated to MHP: Mycoheterotrophy - The Biology of Plants living on Fungi. On page 9 he says: "At least 514 species of angiosperms and a single liverwort species entirely depend on fungal carbon during their complete life cycle". This website aims to set up a list of all mycoheterotrophic plants on earth, combined with additional informations such as synonymy, pictures and a bibliography. So far, the list of accepted species with taxonomic comments as well as synonyms (listed above the accepted taxa, both in alphabetic order) are complete except for Orchidaceae. The bibliography (almost 1300 references) collects the bibliographic data of the taxonomic literature mentioned up to now, as well as other articles dealing with all aspects of mycoheterotrophic plants. The citations in the taxonomic comments (pages) are hyperlinked with the bibliographic data. You find the taxonomic comments under the flag 'Descriptions' when choosing a species name in the taxonomy 'Mycoheterotrophic Plants'.
According to this list 48 non-orchid genera contain mycoheterotrophic species, and 280 non-orchid species are mycoheterotrophic. Dictyostega orobanchoides, Hypopitys monotropa, Voyria aurantiaca, and V. corymbosa are subdivided in subspecies, Afrothismia winkleri, Monotropastrum humile, and Thismia hexagona have one variety each, and Epirixanthes papuana as well as E. elongatata have a form alba, respectively. Aditionally, 20 genera and 75 species of mycoheterotrophic orchids are listed, however, this is far from being complete.

The criterium to be included in this list is "optical achlorophylly" or at least nearly such. We are aware of intergrading dependences on the mycorrhizal fungus even in green plants (see the pages The case of "Pyrola aphylla", Obolaria and Bartonia or Stemona aphylla), as well as of different amounts of chlorophyll content, which often is even hidden by other colouring compounds.