Home • Coemansia mojavensis RSA 71 v1.0
Fig 1) Spirally arranged branched sporangiospores of C. mojavensis. Fig 2) At maturity, each fertile branch produces a cluster of elongate, unispored sporangia. Fig 3) Globose, smooth-walled zygospores of C. mojavensis. Images by Kerry O'Donnell.
Fig 1) Spirally arranged branched sporangiospores of C. mojavensis. Fig 2) At maturity, each fertile branch produces a cluster of elongate, unispored sporangia. Fig 3) Globose, smooth-walled zygospores of C. mojavensis. Images by Kerry O'Donnell.

Coemansia mojavensis R.K. Benjamin NRRL 2692 = CBS 166.58 was originally isolated from rat dung in California by R. K. Benjamin, who formally described and beautifully illustrated this saprobe as a novel species (Benjamin 1958).  It is a member of the Order Kickxellales, which is classified within the recently delimited Phylum Zoopagomycota (Spatafora et al. 2016).  Named after the Mojave Desert in the southern portion of the state, this homothallic species grows and sporulates in pure culture at 25⁰C on a variety of agar media (ex., malt extract 3 g, yeast extract 3 g, peptone 5 g, dextrose 10 g, agar 20 g per L distilled water).  In pure culture, it produces abundant erect, septate sporangiophores that are 3-5 mm tall.  Sporangiospore bearing branches are arranged spirally and exhibit an alternate branching pattern on the terminal portion of the sporangiophores (Fig. 1).  At maturity, each fertile branch produces a cluster of elongate unispored sporangia (Fig. 2).  During the homothallic sexual cycle, undifferentiated vegetative hyphae fuse and develop into globose smooth-walled zygospores (Fig. 3).  The genus Coemansia is paraphyletic because Spirodactylon and Kickxella appear to be nested within it (O’Donnell et al. 1998, Tretter et al. 2014, Chuang et al. 2017). Comparative analyses of the whole-genome sequence of C. mojavensis and other Zoopagomycota should advance our understanding of the phylogeny of the early diverging fungi as part of the NSF-funded Zygomycetes Genealogy of Life project and JGI’s Early Diverging Fungi – 1KFG Community Sequencing Project.

References:
Benjamin RK. 1958. Sexuality in the Kickxellaceae. Aliso 4:149─169.

Chuang S-C, Ho H-M, Reynolds N, Smith ME, Benny GL, Chien C-Y, Tsai C-L. 2017. Preliminary phylogeny of Coemansia (Kickxellales), with descriptions of four new species from Taiwan. Mycologia 109:815─831.

O’Donnell K, Cigelnik E, Benny GL. 1998. Phylogenetic relationships among the Harpellales and Kickxellales. Mycologia 90:624─639.

Spatafora JW, Chang Y, Benny GL, Lazarus K, Smith ME, Berbee ML, Bonito G, Corradi N, Grigoriev I, Gryganskyi A, James TY, O’Donnell K, Roberson RW, Taylor TN, Uehling J, Vilgalys R, White MM, Stajich JE. 2016. A phylum-level phylogenetic classification of zygomycete fungi based on genome-scale data. Mycologia 108:1028─1046.

Tretter ED, Johnson EM, Benny GL, Lichtwardt RW, Wang Y, Kandel P, Novak SJ, Smith JF, White MM. 2014. An eight-gene molecular phylogeny of the Kickxellomycotina, including the first phylogenetic placement of Asellariales. Mycologia 106:912─935.