Pilobolaceae
| Pilobolaceae | |
|---|---|
Scientific classification  | |
| Kingdom: | Fungi |
| Order: | Mucorales |
| Family: | Pilobolaceae Corda (1942) |
| Type genus | |
| Pilobolus Tode | |
| Genera | |
| |
The Pilobolaceae are a family of fungi in the Mucorales order. Generally, species in this family have a widespread distribution, although there are some that are restricted to tropical and subtropical regions.[1] This family includes three genera: Pilobolus, Pilaria, and Utharomyces. [2] [3]
Morphology
All species produce unusual, photorophic sporangiophores. These sporangiophores give rise to dark-colored, columellate sporagia covered in calcium oxalate crystals. In Pilobolus and Utharomyces, inflated structures filled with yellow cartenoid pigments give rise to the sporophores; these two genera also produce subsporangiul vesicles. Zygospores are formed on apposed, entwined suspensors, usually at or below the dung. [2]
Ecology
All species grow on dung but can rarely be isolated from the soil. Pilobolus and Pilaira' are common on many types of herbivore dung, while Utharomyces grows on rodent dung. [2] Utharomyces appears to be restricted to the tropics. [3]
Dispersal
This family has specatular means of dispersal. Many species require passage through the gut of an herbivore in order for the spores to germinate. The problem is that many animals tend to avoid eating their own dung. To compensate, remarkable mechanisms of spore dispersal are used [4]
Pilobolus
In Pilobolus, the subsporangial swelling acts as a lens to focus light on light-sensitive pigments at the base of the swelling. Turgor pressure builds inside of the swelling until it ruptures, and the sporangium is hurled for 2 meters. The calcium oxlate crystals helps it adhere to the surface it lands on, and if the surface is wet, the crystals allow the sporangium to rotate. This rotation allows the mucus surronding the spores (under the crystals) to glue it to surface where it will await ingestion by an herbivore. Interestingly, nematodes have been observed climbing the sporangiophore or swimming inside of it to catch a ride on the sporangium. While many species may do this, it seems only Dictyocaulus vivipores, cattle lungworm, are able to survive the trip. [2]
Pilaira & Utharomyces
Mechanisms of dispersal are less known in these genera. In both genera,the sporangiophore, guided by light, elongates until the sporangium is brought into contact with a solid surface. In Pilaira, contact with the surface causes a rupture at the columella, which releases the sporangium, which adheres to the new surface using a method similar to Pilobolus. In Utharomyces, contact with the surface ruptures the subsporangial swelling. This releases cytoplasm, which is used to glue the upper portion of the swelling containing the sporangium to the substrate. [2]
References
- ↑ Cannon PF, Kirk PM. (2007). Fungal Families of the World. Wallingford: CABI. p. 261. ISBN 0-85199-827-5.
- ↑ 2.0 2.1 2.2 2.3 2.4 Alexopoulos C. J., C. W. Mims, & M. Blackwell. 1996. Introductory Mycology. Fourth Edition. John Wiley & Sons, Inc.
- ↑ 3.0 3.1 Hesseltine C. W. & J. J. Ellis. 1973. Mucorales. in: The Fungi: An Advanced Treatise. Volume 5B. A Taxonomic Review with Keys: Basidiomycetes and Lowr Fungi. Academic Press. New York. pg. 187-217.
- ↑ Kendrick, Bryce. 2000. The Fifth Kingdom. Third Edition. Focus Publishing & R. Pullins Company. Newburyport, MA.
External links
- Index Fungorum
- Pilobolus crystallinus, "The Fung in the Dung" by Tom Volk
- Pilobolus and the Lungworm at the Cornell Mushroom Blog (with time lapse video)
- Interview with a Fungus
- Zygomycetes:Pilobolus at Zygomycetes.org
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