Fungal mimicry in the deceptive pollination of Dracula orchids
Website created by Bryn T. M. Dentinger (2006), last updated 2011.
For a more detailed overview of this project, download my paper in McIlvainea.
Questions about this project or website? email me: b.dentinger at kew.org
image from Behar (1995)
The remarkable fungal mimicry of Dracula orchids is illustrated by this side-by-side comparison of a gilled mushroom and the flower of Dracula vampira.

This research project is exploring the natural history of deceptive pollination in Dracula orchids. In these orchids, extraordinary modifications of their flowers have evolved that look like, feel like, and smell like mushrooms. This project will investigate how orchids (THE MIMICS) can deceive pollinating insects (THE DUPES) by resembling fleshy fungi (THE MODELS). Some of the questions being addressed are:
How did the orchids arrive at these bizarre floral characteristics?
Who are they mimicking?
Why don't the insects evolve the ability to avoid being duped?

THE MIMICS (Dracula spp.)
Figure 1 from Dentinger & Roy (2010)
Examples of Dracula orchids. A) D. bella (labellum), B) D. carleuri, C) D. vespertilio, D) D. chestertonii, E) D. orientalis, F) D. felix, G) D. roezlii, H) D. inaequalis. Scale bar is 10 mm and approximate based on published dimensions. All photos by Bryn Dentinger.

These orchids may be mimicking certain fungi through visual appearances, tactile sensations, and/or fragrances that they emit from the flowers. At present, no one has investigated how these traits function or who the models might be...

THE DUPES
(Zygothrica spp., pollinators)
images from Grimaldi (1986)
These insects belong to a large neotropical genus of fruit flies. Very little is known about their true diversity or life histories, except that they are all obligately associated with fleshy fungi. Some recent studies indicate that these flies may be the sole pollinators of Dracula orchids (Endara et al. 2009)...

THE MODELS?
(fleshy fungi)
Figure 2 from Dentinger & Roy (2010)
Potential models for the mimicry by Dracula orchids. A) Chaetocalathus sp., B) Cheimonophyllum sp., C) Crinipellis sp., D) Xerulina chrysopepla, E) Hydropus sp. F) Filoboletus gracilis, G) Mycena sp., H) Marasmius sp. Scale bar is 1 cm. All photos by Bryn Dentinger.

Map of Ecuador and approximate location of the field site where the field research is taking place, Los Cedros Reserve
(indicated by the blue oval)

Some images from Los Cedros Reserve
images borrowed with permission from their website www.reservaloscedros.org

Anatomy of Dracula
images from Luer (1993)
The flowers of Dracula orchids are always presented near the ground, at the level where most fleshy fungi occur (see drawing at left). At right, the elaborate construction of Dracula's sexual organs requires that the pollinator transfers the packets of pollen (c.) to another flower's stigma (d.) to achieve sexual reproduction.

REFERENCES
Behar, M. 1995. Evolution and orchids. American Orchid Society Bulletin 64(12):1326-1332.
Dentinger, B. T. M., and B. A. Roy. 2010. A mushroom by any other name would smell as sweet: Dracula orchids. McIlvainea 19(1):1-13.
Endara, L., D. A. Grimaldi, and B. A. Roy. 2010. Lord of the flies: pollinatio of Dracula orchids. Lankesteriana 10(1):1-11.
Grimaldi, D.A. 1986. Systematics and biology of the large tropical genus of fruit flies, Zygothrica (Diptera: Drosophilidae). Ph.D. Dissertation. Cornell University.
Luer, C. A. 1993. Icones Pleurothallidinarum X. Systematics of Dracula (Orchidaceae). Monographs in Systematic Botany vol. 46. Missouri Botanical Garden, St. Louis, MO. 244p.

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The contents of this page have not been reviewed or approved by the University of Minnesota.