Within the Gentian family, four genera contain mycoheterotrophic species. Voyria has more than a dozen species, the other genera Voyriella, Exacum, and Exochaenium contain only a few mycoheterotrophic species. Some green gentians are potentially partially mycoheterotrophic (Obolaria, Bartonia).
FACT SHEET
Classification: Eudicots, Gentianales
Genera with mycoheterotrophic species: Voyria, Voyriella, Exacum, Exochaenium
Diversity: Gentianaceae comprise 92 commonly accepted genera and over 1,650 species. Twenty-five species are achlorophyllous and putative full mycoheterotrophs. These species are part of four genera: Voyria, Voyriella, Exacum, and Exochaenium. Species of the North American genera Bartonia (four spp.) and Obolaria (one sp.) are partial mycoheterotrophs. Partial mycoheterotrophy is suggested to occur in Curtia tenuifolia and species of Neurotheca as well.
Distribution and habitat: Gentianaceae are a cosmopolitan family, absent only from Antarctica. The majority of the species occurs in temperate zones but the mycoheterotrophic species are restricted to rain forests in the Americas (Voyria, Voyriella), West Africa (Voyria, Exochaenium), and Southeast Asia (Exacum). Apart from tropical forests some species of Voyria also occur in savannas and extend into subtropical Central America.
Pictures
Voyria clavata (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria aurantiaca (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria aurantiaca (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria parasitica (Gentianaceae) – Las Terrazas, Cuba. Photo by Vincent Merckx
Voyria corymbosa (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria aphylla (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria aphylla (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria aphylla (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyriella parviflora (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria sp. (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria sp. (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (front and right) and V. corymbosa (left) (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (right) and V. corymbosa (left) (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria tenella (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria obconica (Gentianaceae) – Root systems. Brazil. Photo by Vincent Merckx
Voyria obconica (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria obconica (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria obconica (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria flavescens (Gentianaceae) – Brazil. Photo by Vincent Merckx
Voyria flavescens (Gentianaceae) – Brazil. Photo by Vincent Merckx
Exochaenium oliganthum (Gentianaceae) – Mount Kupe, Cameroon. Photo by Vincent Merckx
Voyria aphylla (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria caerulea (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria clavata (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyria corymbosa (Gentianaceae) – French Guiana. Photo by Vincent Merckx
Voyriella parviflora (Gentianceae) – French Guiana, Photo by Vincent Merckx
Voyria pittieri (Gentianceae) – Colombia, Photo by Vincent Merckx
VVoyria chionea (Gentianceae) – Colombia, Photo by Vincent Merckx
Voyria corymbosa (Gentianaceae) – French Guiana
mycoheterotrophy 