Mitrastemonaceae Makino

Family Description

Distribution Map

List of Genera

Photographs

Mitrastema matudae

1. Photo. Chiapas. Photo by Dennis Breedlove.

Mitrastema yamamotoi

1. Photo. Plants in full flower, showing circumscissile dehiscence of the androecial tube. Near Muroto-Shi, Kochi, Japan. Photograph by Michiyo Satou, published in "World of Plants" article by Mitsuru Hirota (Weekly Asahihyakka, Jan. 22, 1995). Used with permission.
2. Photo. Plants just past flower. From the website of the Meeting of Miyakonojo valley plant lovers, color photo album and flora (Japan).
3. Photo. On roots of Shikoku (Okinawa shii). Photo taken 15 November 1987. From "Praising Flowers" website, Japan. 
4. Photo. Tokushima prefecture Kaifu Gun. Photo taken 26 November 1989. From "Praising Flowers" website, Japan.
5. Drawing (from Makino 1911) by D. Nickrent. Emerging bud (right) and open flowers (left and middle), both in female phase.
6. Photo. Habit of plant at Lien-hua-Chih, Taiwan. Photo taken Nov. 11, 1995 by Shu-Chuan Hsiao.
7. Photos. Series of photos of the flower. Taiwan. Photos by Mutolisp (Psilotum Lin). Link goes to Flickr.
8. Photos. Series of photos of the flower. Taiwan. Photos by Mingiweng. Link goes to Flickr.
9. Photo. Plants in flower. Nantou region, Taiwan. Photos by Leejoseph. Link goes to Flickr.
10. Photo. Close-up of plant at Chitou, Taiwan. Photo taken Mar. 15, 1995 by Shu-Chuan Hsiao.

A number of names of Mitrastema have been (and are currently being) used to refer to Asian material: M. cochinchinensis, M. sumatranus, M. kanehirai, M. kawasakii, and M. yamamotoi. The latter three names, originally proposed by Yamamoto (1925, 1926), were later used by Watanabe in a large number of publications in the 1930s (see references). Characters used to support the specific status of these taxa involved the number of scale leaves (up to six pairs vs. 8-12 pairs), their shape (small, elongate elliptic vs. large, oblong), and plant aspect (cylindrical vs. 4-angled, obconic). The most recent work to examine the taxonomy of Mitrastema was Meijer and Veldkamp (1993) who concluded that because many intermediates among these "species" exist, the variation represents local forms and ecotypes and that all Asian specimens should be regarded as one variable species. Moreover, as pointed out by van Royen (1963), all forms can be found in material from Papua New Guinea. Hansen (1973) stated that it was not possible to distinguish at the specific level the southeast Asian and Malesian populations. Although technically challenging given the rarity of these plants, a populational biosystematic study using molecular markers is likely required to determine whether one or more species exist in Asia. Until then, the conservative approach taken by Hansen (1973) and Meijer and Veldkamp (1993) will be followed here.

And finally, some words on the spelling of the generic and family names. The Latin "mitra" refers to mitre and "stema" to thread or stamen, aluding to the mitre-shaped staminal tube. Unfortunately, Makino (1909) accidentally used "stemma" which means garland or wreath, but being an orthographic error, it can be corrected under the rules of botanical nomenclature. There are several orthographic variants of the generic name, including Mitrastemma, Mitrastemon, and Mitrastema (I have not seen Mitrastemmon, but it's likely out there too!). These variants also spill over into the family name: Mitrastemonaceae Makino (in Bot. Mag. Tokyo 25:252) was conserved in 1966 (ICBN App. IB) and Mitrastemataceae (used by Mabberley in his 2008 edition of the Plant Book). 

Phylogeny

References