The family Apodanthaceae comprises about 10 species of endoparasitic

herbs Herbs are a widely distributed and widespread group of plants, excluding vegetables, with savory or aromatic properties that are used for flavoring and garnish (food), garnishing food, for medicinal purposes, or for fragrances. Culinary use typi ...

. They live in the branches or stems of their hosts (as filaments similar to a fungal

mycelium Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are fo ...

), emerging only to flower and fruit. The plants produce no green parts and do not carry out any photosynthesis (that is, they are holoparasitic). There are two genera: '' Pilostyles'' and '' Apodanthes''.Albert Blarer, Daniel L. Nickrent, and Peter K. Endress. 2004. "Comparative floral structure and systematics in Apodanthaceae (Rafflesiales)". ''Plant Systematics and Evolution'' 245(1-2):119-142. A third genus, ''Berlinianche'', was never validly published.Bellot, S., and S. S. Renner. 2013. "Pollination and mating systems of Apodanthaceae and the distribution of reproductive traits in parasitic angiosperms". "American Journal of Botany" 100(6): 1083–1094. The native range of Apodanthes is restricted to Central and tropical South America, while Pilostyles has a much wider though disjointed native range, encompassing many countries in tropical and subtropical America, a section of Africa from

Gabon Gabon ( ; ), officially the Gabonese Republic (), is a country on the Atlantic coast of Central Africa, on the equator, bordered by Equatorial Guinea to the northwest, Cameroon to the north, the Republic of the Congo to the east and south, and ...

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

and down to

Zimbabwe file:Zimbabwe, relief map.jpg, upright=1.22, Zimbabwe, relief map Zimbabwe, officially the Republic of Zimbabwe, is a landlocked country in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Bots ...

, as well as Turkey, Iran, Iraq, and Western Australia.

Taxonomy

The relationship of the Apodanthaceae to other plant families remains unresolved, though recent research has given more clarity to the family's position and suggests inclusion in the order

Malpighiales The Malpighiales comprise one of the largest Order (biology), orders of flowering plants. The order is very diverse, with well-known members including willows, Viola (plant), violets, aspens and Populus, poplars, Euphorbia pulcherrima, poinsett ...

with a possible link to the family

Rafflesiaceae The Rafflesiaceae are a family of rare parasitic plants comprising 36 species in 3 genera found in the tropical forests of east and southeast Asia, including ''Rafflesia arnoldii'', which has the largest flowers of all plants. The plants are e ...

. While the

APG III system The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy being developed by the Angiosperm Phylogeny Group (APG). Published in 2009, it was superseded in 2016 by a f ...

of classification (2009) listed the family's taxonomic position as uncertain, the APG IV update in 2016 assigned it to the

Cucurbitales The Cucurbitales are an order of flowering plants, included in the rosid group of dicotyledons. This order mostly belongs to tropical areas, with limited presence in subtropical and temperate regions. The order includes shrubs and trees, togeth ...

based on mitochondrial and nuclear DNA sequences.Filipowicz, N., and S. S. Renner. 2010. "The worldwide holoparasitic Apodanthaceae confidently placed in the Cucurbitales by nuclear and mitochondrial gene trees." ''BMC Evolutionary Biology'' 10:219 However, two 2024 studies, both of which use large sets of nuclear DNA for analysis, indicate that it is a basal member of the Malpighiales. The difficulty with using

plastid A plastid is a membrane-bound organelle found in the Cell (biology), cells of plants, algae, and some other eukaryotic organisms. Plastids are considered to be intracellular endosymbiotic cyanobacteria. Examples of plastids include chloroplasts ...

DNA for phylogenetics of the Apodanthaceae was discussed in a 2021 study by Li ''et al.'' This paper refers to the Apodanthaceae as one of five 'problematic' families (along with

Balanophoraceae The Balanophoraceae are a subtropical to tropical family of obligate parasitic flowering plants, notable for their unusual development and formerly obscure affinities. In the broadest circumscription, the family consists of 16 genera. Alterna ...

Mitrastemonaceae ''Mitrastemon'' is a genus of two widely disjunct species of parasitic plants. It is the only genus within the family Mitrastemonaceae. ''Mitrastemon'' species are root endoparasites, which grow on Fagaceae. It is also a non-photosynthetic plant ...

, and Thismiaceae) and notes that

plastome Chloroplast DNA (cpDNA), also known as plastid DNA (ptDNA) is the DNA located in chloroplasts, which are photosynthetic organelles located within the cells of some eukaryotic organisms. Chloroplasts, like other types of plastid, contain a genom ...

sequences in these families are highly reduced and they have unusually high substitution rates in the retained sequences, which can hamper proper phylogenetic alignment and cause

long branch attraction In phylogenetics, long branch attraction (LBA) is a form of systematic error whereby distantly related lineages are incorrectly inferred to be closely related. LBA arises when the amount of molecular or morphological change accumulated within a lin ...

artifacts.

External links

Parasitic Plant Connection: Apodanthaceae

References

{{Taxonbar, from=Q134410 Parasitic plants Rosid families