No sooner discovered my first local mycoheterotroph Voyria tenella Hook, of Gentianaceae (http://bit.ly/atxXaX), on one of my short motorbike trips to the nearby patch of virgin Atlantic forest, accompanied (actually driven) by my house help (turned fellow plant and animal collector) Louro, as another mycoheterotroph, this time from Burmanniaceae, was spotted when looking for a good-size infructescence of what I eventually (and provisionally) was able to determine to be Orthomene schomburgkii (Miers) Barneby & Krukoff, of Menispermaceae (http://bit.ly/9Cbfjv).  Its pale looking chlorophyll-less inflorescences were barely noticeable in the midst of the layer of decaying leaves in the dark of the understory vegetation.

Habitat

We collected some specimens of it and, upon photographing, put them in the 70% alcohol solution for deposit into my plant collection at the HUEFS (Herbarium of the State University at Feira de Santana, Bahia, Brazil).

At home I was unable to come up with the family and genus ID, using my available resources (mostly those of the Internet), apart from realizing that like Voyria tenella it was a mycoheterotroph.  I then sent some of its images to Daniel Nickrent, a well-known specialist in parasitic plants at Southern Illinois University in Carbondale who had previously identified my Voyria species.  In a couple of hours I had his feedback: Gymnosiphon species, of Burmanniaceae, a new family record in my study of the local flora.  An online search for its distribution records for Bahia, Brazil, using SpeciesLink (a database of several Brazilian herbaria holdings, http://bit.ly/agXYU8), narrowed down the species search to Gymnosiphon divaricatus (Benth.) Benth. & Hook. f., as the only species recorded for my area. Some additional research of the available images and a perusal of the Flora Neotropica monograph of the family by Paul Maas and collaborators (vol. 42, Burmanniaceae, 1986) confirmed the species ID.  The Latin ‘divaricatus’ means ‘straggly, spreading’, evidently in reference to the bifurcate form of this plant’s inflorescence and the general ‘straggly’ appearance.

Bifurcate inflorescence

According to Maas, the flowers are scented.  I haven’t felt any noticeable scent.

The species is distributed in forests of Central and South America.

Additional images are on my Flickr pages (http://bit.ly/cTZvSL).

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One of the flowering plants that have abandoned photosynthesis but is not a haustorial parasite is Voyria, Gentianaceae, that I and my co-collector Louro have discovered on yesterday’s collecting trip to the nearby patch of the virgin Atlantic forest at Imbé (Entre Rios, Bahia, Brazil).  According to  Daniel L. Nickrent of Southern Illinois University at Carbondale, IL, “these plants are frequently mistaken for parasitic plants but are more accurately called myco-heterotrophs (also sometimes mycotrophs).  [They] … can live without photosynthesis because they have established a coevolutionary relationship with a mycorrhizal fungus that is attached to the root of a photosynthetic, woody plant. So, there is a three way association such that nutrients (carbon) flow from plant root, to mycorrhizal fungus to the myco-heterotroph. … The mycotrophs don’t directly invade the photosynthetic “host” roots but indirectly obtain nutrients via the intermediate fungus. … [M]yco-heterotrophs are frequently mistakenly called saprophytes.  There are no true saprophytes in the angiosperms.  Only fungi can directly utilize dead organic material.”

Specimens of mycotrophs need to be preserved in 70% alcohol. Luckily, we were prepared for such an eventuality.

See http://www.parasiticplants.siu.edu/Mycotrophs/Mycotrophs.html and http://www.newphytologist.com/view/0/virtspecissueMyco.html for further information.

Symbiotic seed germination is widespread in orchids.

PS. Thanks go to Dan Nickrent for the identification of the genus and Paul Maas for pinpointing the species.

Paul Maas is the author of a monograph on Voyria (Maas, P. J. M. & P. Ruyters. 1986. Voyria and Voyriella  (saprophytic Gentianaceae). Flora Neotropica Monograph 41. The New York Botanical Garden, Bronx, NY).