Home • Dichotomocladium elegans RSA 919- v1.0
Figures 1 and 2: Unispored sporangiola in terminal heads composed of dichotomously branched fertile hyphae. Images by Gerald Benny.
Figures 1 and 2: Unispored sporangiola in terminal heads composed of dichotomously branched fertile hyphae. Images by Gerald Benny.

Dichotomocladium elegans Benny & R.K. Benj. (strain RSA 919) is the type species of this zygomycetous genus, which is currently classified within the Lichtheimiaceae [order Mucorales, phylum Mucoromycota; Spatafora et al. 2016].  When this genus was originally described, it was placed in the Thamnidiaceae (Benny and Benjamin 1975); however, molecular phylogenetic studies have revealed that this family is polyphyletic (O’Donnell et al. 2000, Walther et al. 2013).  This species has been isolated from dung collected in the Mexican state of Baja California and California (Benny and Benjamin 1975).  During the asexual phase of its life cycle, D. elegans produces sporangiophores that bear unispored sporangiola in terminal heads composed of dichotomously branched fertile hyphae (Figs. 1-2).  The sexual reproductive phase of this heterothallic or self-sterile species is characterized by the formation dark, ornamented zygospores between the opposed suspensors of mating compatible strains.  Sequencing of D. elegans RSA 919 will advance the NSF-funded Zygomycetes Genealogy of Life Project and 1000 Fungal Genome Project by providing a representative genome for the Lichtheimiaceae, an important family of mucoralean fungi and additional insight into the evolution of nutrient cycling among early diverging fungi.

References:

Benny GL, Benjamin RK. 1975. Observations on Thamnidiaceae (Mucorales). New taxa, new combinations, and notes on selected species. Aliso 8:301–351.

O’Donnell K, Lutzoni FM, Ward TJ, Benny GL. 2000. Evolutionary relationships among mucoralean fungi (Zygomycota): Evidence for family polyphyly on a large scale. Mycologia 93:286–296.

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.

Walther G, Pawłowska J, Alastruey-Izquierdo A, Wrzosek M, Rodriguez-Tudela JL, Dolatabadi S, Chakrabarti A, de Hoog GS. 2013. DNA barcoding in Mucorales: an inventory of biodiversity. Persoonia 30:11–47.

Genome Reference(s)