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C. umbellata’s sporagiaphores are thin and branched, with a short apophysis. Their coloration ranges from hyaline to brown, getting darker nearer to the sporangia. The sporangia are rough textured and grow singularly or in umbles of 8-12 sporangia (which is a unique characteristic). The umbles grow from branches on the sporangiophore, and they sometimes can occur on the terminal end of the sporagiophore. The sporangia are small, circular and colored black or smoky grey with a persistent wall that breaks at maturity.The columella is small, brown and pear shaped with a collar at the base. C. umbellata’s spores are spherical and have thick walls. The color of the spores can be hyaline to brownish, with the center of the spore being a darker tint. C. umbellata’s zygospores are smooth walled and oval shaped with several oil droplets during immaturity. Once the spores are mature, the oil droplets merge into one larger drop in the center of the zygospore. The suspensor cells of C. umbellata are long and ovulate. Usually the ends of the suspensor cells are coiled but they can be straightwhile the suspensor cells are smooth walled and hyaline to slightly brown. C. umbellatas hyphae are white, forming a cobweb like mycelium.(Hesseltine, C., & Fennell, D. 1955)
C. umbellata is corpophillic (meaning it grows on dung), and does not have a very high chance of meeting opposite mating types compared to non-coprophillic fungi. Because of this, C. umbellata resorts to asexual reproduction frequently. The umbles of sporangia that C. umbellata produce will open and spread haploid spores into the surrounding area. These spores are distributed onto grass and other vegetation which gets eaten, and the process starts over again. When sexual reproduction does occur, two suspensor cells will fuse to create a zygote.
Like other species in Mucoracea, C. umbellata is a terrestrial fungus and is saprobic, meaning it feeds on decaying organisms (1955). While it is predominantly known to be found on dung, making it coprophilic (1976), it can also be found in decaying organic matter, such as tree nuts and soil. C. umbellata has been discovered on the dung of mammals, including rabbits, rats, deer and bats (2009, 1955). In a study preformed in New York, C. umbellata was found on the dung of lions and jaguars as well as horses (1976). This is interesting because coprophilic fungi generally do not associate with carnivores, as there is less nutrient in carnivore’s excrement. A study conducted on guanophillic species in Puerto Rico found that out of the fifty-species found of fungi found in the bat dung of three caves, the dominant species in was C. umbellata (2009). This species of fungi is widespread, being documented in many parts of the world with notable locations such as the United States, Spain, Pakistan, India, the United Kingdom, Ghana, Brazil, and Sri Lanka(2016).
The establishment of locations where this species has been found, but no significant research into the economic benefits of C. umbellata have occurred. Ecologically, besides the saprobic nature of C. umbellata, it has not been extensively studied. Because it is coprophilic, the species does help in nutrient cycling by consuming dung. C. umbellata was found on rat feces in 1344 during the black plauge, though it was not described until 1873. This suggests a correlation, because the black plague was partially caused by infected rat carcasses (Hesseltine, C., & Fennell, D. 1955)
Fifty species of guanophilic (bat guano-loving) fungi were isolated from field-collected samples within three caves in southwestern Puerto Rico; most were mitosporic fungi (23 species). The caves studied were Cueva La Tuna (Cabo Rojo), Cueva de Malano (Sistema de Los Chorros, San Germán), and Cueva Viento (El Convento Cave-Spring System, Guayanilla-Peñuelas). The most conspicuous fungus by far was the zygomyceteCircinella umbellata(Mucorales).Circinella umbellatadominated the bat guano incubation chambers (Petri dishes lined with sterile filter paper moistened with sterile water) at ambient laboratory conditions. Nineteen species of basidiomycetes (e.g.,Ganodermacf.resinaceum,Geastrumcf.minimum,Lepiotasp.,Polyporussp.,Ramariasp.) and three species of ascomycetes (Hypoxylonsp.,Xylaria anisopleura, andX. kegeliana) were also recorded. They were found on soil, rotting leaves, bark and rotting wood, buried in bat guano located below natural skylights or sinkholes. (International Journal of Speleology 2009)
Grit Walther, a doctor at the National Reference Center for Invasive Fungal Infections, lead a team of scientists on a study of DNA Barcoding in Mucoraceae, including genus Circenella. The results found that the phenotypic classifications of Mucoraceae are highly artificial. The LSU- and ITS taxonomic trees found some characters, like the rhizoids and sporangioles that are used to distinguish mucoraceae are plesiomorphic traits, meaning they were derived ancesterally (2013). The ITS region was the most accurate barcoding method for Mucorales (1955), directly sequencing in eighty-two percent of the strains. Molecular identification was problematic in some of the species complexes of Mucor, but C. umbellata was sequenced succesfully (2013). The study also found twelve potentially new species yet to be described (2013).
A study was conducted by Hoffman on the degradation of n-alkanes in the order Mucorales. Of the thirty-four strains tested (including C. umbellata), twenty-nine strains showed good growth on solid media containing n-alkanes (1976). From this information, the study concluded that the order Mucorales may contain a sub-terminal pathway for degradation of aliphatic hydrocarbons (1976). A study done by Walther et. al. (2013) barcoded the genome of the order Mucorales using an ITS sequence. This project barcoded C. umbellata, among several other species (2013).
A brief summary ofC. umbellata
A detailed summary ofC. umbellataby Gerald L. Benny, a researcher and professor at theuniversity of Florida.
