Mystropetalaceae Hook. f.

Family Description

Distribution Map

List of Genera

Photographs

Dactylanthus

1. Dactylanthus taylori
   • Photo A monotypic genus endemic to New Zealand. These three inflorescences, showing hundreds of small male flowers laden with white pollen, will each have a pool of up to 1.5 ml of nectar inside the protecting bracts. Photo from Ecroyd (1995, Nature Conservation 4: The Role of Networks, Surrey Beatty & Sons. Used with permission).
   • Photo. Shown is a short-tailed bat (Mystacina tuberculata) feeding on the nectar from a male inflorescence of the root parasite. Bats appear to be the primary pollinators of Dactylanthus. Photo by Eric Anderson and Chris Ecroyd.
   • Photo. Germinating seed with long hairs growing from the 'radicle.' Photo by B. O'Brien and S. Holzapfel. From Ecroyd (1996, New Zealand Journal of Ecology, 20:81-100).
   • Photo. Scanning electron micrograph of cellular structure of seedling. Note intracellular fungal hypha (indcated by arrows. Photo from Ecroyd (1996, New Zealand Journal of Ecology, 20:81-100).
   • Photo. Woodrose formed by the host root in response to the root parasite. Photo from Ecroyd (1995).
   • Dactylanthus taylorii is under threat by several mammals that feed on the inflorescences. The introduced Australian brush-tailed possum (Trichosurus vulpecula), shown in the upper picture, is attempting to get through a netting exclosure. The lower picture shows the ship rat (Rattus norvegicus) is responsible for some pollination but also destroys flowers.
   • Plate 1 of four images from the New Zealand Plant Conservation Network. A. young tuber (Avi Holzapfel); B. Tuber partly exposed and inflorescence (Avi Holzapfel); C. group of inflorescences (Chris Ecroyd); D. inflorescence (NZ Department of Conservation).
   • Plate 2 of four images from the New Zealand Plant Conservation Network. A. female plant with inflorescences (Nick Singers); B. plant with lighter (yellow) inflorescence bracts (Nick Singers); C. inflorescence in hand (Avi Holzapfel); D. infructescence (Avi Holzapfel).
   • Web page about conservation of Dactylanthus.  From the New Zealand Department of Conservation.

Hachettea

1. Hachettea austro-caledonica
   • Photo. Male inflorescence. Link goes to the Vascular Plant Families web page of Gerald Carr (Univ. Hawaii). Photo by Tim Motley.
   • Photo. Male flowers, close-up. Link goes to the Vascular Plant Families web page of Gerald Carr (Univ. Hawaii). Photo by Tim Motley.
   • Photo. Young inflorescence emerging from the soil, not yet open. Mt. Ouin, New Caledonia. Photo by Sarah Mathews.
   • Photo.  Young inflorescences just beginning to open.  New Caledonia.  Photo by R. A. Howard (see Plant Image Collection, Smithsonian Inst.)
   • Photos Female plant showing formation of fruits. Col d'Amieu, New Caledonia. Link goes to Flora of the World.
     
   • Photos.  A series of photos and descriptions (in French). For a Google translation of the page to English, go HERE.  Link goes to Endemia.nc.

Mystropetalon

How many species in Mystropetalon?  Three species of this South African genus have been named.  The last one, M. sollyi [spelled M. sollyae in IPNI] was named by Harvey-Gibson (1913. Bot. J. Linn. Soc. Bot. 8:143-154; HERE].  Although his tabular comparison looks convincing as written, Hansen (1986) attempted to use these characters to distinguish the three species with 50 herbarium and FAA-fixed specimens. He found that the features showed great variation, even on one specimen. I am following his concept here that Mystropetalon is monospecific. As far as I know, there has not been a modern examination of these purported species.

1. Mystropetalon thomii
   • Photo Individual plant with older genets toward outside, young genet on inside of ring. The young shoot is in the female (pistillate stage). Near Kleinmond, South Africa. (voucher no. DLN 4091). Photo by D. L. Nickrent.
   • Photo Same plant as above, but excavated to show that all genets arise from the same stem. Note the new shoots being formed. A curious finding was the presence of liquid surounding the central stems. Is this produced by the parasite? What is its function? Photo by D. L. Nickrent.
   • Photo Old (left) and new (right) shoots in male (staminate) flower phase. Photo by D. L. Nickrent.
   • Photo Succession of floral stages present on one inflorescence. The shoot on the right has female flowers forming fruits below, old male flowers in the middle, and young male flowers at the top. Photo by D. L. Nickrent.
   • Photo Close-up of very young shoot forming female flowers. Note the long styles that project from the inflorescence. Photo by D. L. Nickrent.
   • Photo Female (top) and male (bottom) flowers. The ring-shaped, white elaisome that sits below the ovary can be seen enclosed within bracts of the female flower. (Note: the fruit/elaiosome is upside down). The elaiosome is harvested by ants which disperse the one-seeded fruits. The male flowers contain two rather typical stamens (as compared to other Balanophoraceae!) that are attached to the perianth (tepals). The flower is then subtended by bracts and bracteoles. Photo by D. L. Nickrent.
   • Photo. Group of inflorescences. Betty's Bay, South Africa. As Mystropetalon polemannii. Photo by L. J. Musselman
   • Photo. Close-up of inflorscence. Betty's Bay, South Africa. As Mystropetalon polemannii. Photo by L. J. Musselman
   • Photo. Close-up of flower. Betty's Bay, South Africa. As Mystropetalon polemannii. Photo by L. J. Musselman.
   • Photo. Three photographs showing inflorescence, fruits and seeds. As Mystropetalon polemannii Link goes to Plant Web, plants of South Africa by Peter Swart.

New Molecular Data: Mystropetalaceae is distinct from Balanophoraceae!

The most comprehensive (in terms of taxon sampling and genes) molecular analysis of Santalales to date was reported in Su et al. (2015) - pdf file HERE.  From previous molecular phylogenetic work in the Nickrent lab, it was known that the three "Gondwanan" genera, Dactylanthus, Hachettea and Mystropetalon formed a clade and the remaining genera formed another clade. When these were analyzed together with all available genera in Santalales, "Balanophoraceae" was not monophyletic. Tests showed that placing these clades together was not statistically supported. You can visit the Balanophoraceae page HERE.

References