| Mitrastemon | |
|---|---|
 | |
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Ericales |
| Family: | Mitrastemonaceae Makino[1] |
| Genus: | Mitrastemon Makino |
| Species | |
M. matudae | |
Mitrastemon is a genus of two widely disjunct species of parasitic plants.[2] It is the only genus within the familyMitrastemonaceae.Mitrastemon species are root endoparasites, which grow onFagaceae. It is also a non-photosynthetic plant that parasitizes other plants such asCastanopsis sieboldii.
The parasitic species,Mitrastemon yamamotoi(Makino) Makino was found in Japan in 1909. It was originally namedMitrastemma yamamotoiMakino by botanistTomitaro Makino (1862 – 1957),[3] but was later renamed asMitrastemon yamamotoi in 1911.[4]
Then speciesMitrastemon matudae was discovered by botanistEizi Matuda during an expedition toMt. Ovando (near the town ofEscuintla, Chiapas) in the state ofChiapas, Mexico (Matuda, 1947).[5][6] The species was originally named by a botanist friend of Matuda, Yoshimatsu Yamamoto (1893-1947),[7] in 1925–1926, but then published in 1936.[8]Mitrastemon yamamotoi is aprotandrous plant. Its flowers go through a male phase before transforming into their final female form. The flowers ofM. yamamotoi attract a variety of insects ranging from wasps to flies and beetles. Among these, beetles are the best pollinators for this plant since their visit to the flower would pick up a large amount of pollen and they would pollinate from each of the flowers that they had already visited.[5] The plant is endemic to tropical and subtropical forest regions such as southeast Asia and Japan.
OriginallyMitrastemon was placed within the orderRafflesiales, together with other parasitic plants, but this order was long suspected to be actually polyphyletic. In 2004, the genus was found to be related toEricales by comparing theirmitochondrial DNA.[9]
Several orthographic variants of the nameMitrastemon exist, includingMitrastema andMitrastemma. The correct taxonomic name isMitrastemon, the use of which was proposed and justified in an article by Reveal[10] and approved by theNomenclature Committee for Vascular Plants of theInternational Association for Plant Taxonomy in a subsequent article.[11]
The species has a cylindrical body ranging from 3 cm to 7 cm in height with a tuberous base. During an early developmental stage it appears an off-white color; however, once it is dried it becomes a dark brown color (Miret al., 2016).
The plant is observed only during the winter season and it completes its visible life cycle from November to April (Miret al., 2016).Mitrastemon is completely embedded within the tissues of its host, except during the reproduction stage when above-ground parts emerge from host tissues.
Unlike other plants, the flowers of this organism change sex from male to female. Various insects are involved inpollination.Mitrastemon yamamotol is mainly pollinated by social wasps, but previously unnoticed pollination are also important, based on visitation frequency and pollen loads. There have been studies of the pollination that suggest that nocturnal visitors, such as crickets and cockroaches, contribute togeitonogamous pollination. Diurnal visitors like social wasps facilitate outcrossing.[12]
There are two known species;[12][13]
Mitrastemon yamamotoi is distributed in tropical and subtropical forests of Southeast Asia and Japan.Mitrastemon matudae is distributed from southern Mexico to Colombia.[13]
