ABSTRACT
Four new species of Coemansia from Taiwan are described. Three produce spirally twisted sporangiophores, and these new taxa increase the number of species in the Coemansia spiralis complex from three to six. Each new taxon is morphologically unique. Coemansia biformis, sp. nov., has two different asexual reproductive types on the same thallus; one is straight and the other has a spiral fertile region. Coemansia helicoidea, sp. nov., has stoloniferous sporangiophores with a helicoid fertile region. Coemansia pennisetoides, sp. nov., has a sporangiophore with a fertile region that resembles the inflorescence of the plant genus Pennisetum. Coemansia umbellata, sp. nov., has an umbellate sporangiophore branching pattern and a spirally twisted fertile region on the lowest branches. A dichotomous key was provided to identify the 23 accepted Coemansia species. Phylogenetic analysis based on a combined data set of D1-D2 domains of nuc 28S ribosomal RNA (rDNA) and partial nuc 18S rDNA identifies several independent evolutionary lineages within Coemansia and suggests that Spirodactylon aureum and Kickxella alabastrina may be nested within the genus Coemansia. Sequences of nuc rDNA ITS1-5.8S-ITS2 (internal transcribed spacer [ITS] barcode) are also used to support the description of these new species of Coemansia.
Subject(s)
Fungi/classification , Fungi/isolation & purification , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Fungi/cytology , Fungi/genetics , Microscopy , Phylogeny , RNA, Ribosomal, 18S/genetics , RNA, Ribosomal, 28S/genetics , RNA, Ribosomal, 5.8S/genetics , Sequence Analysis, DNA , Soil Microbiology , TaiwanABSTRACT
A new anaerobic rumen fungus was isolated from the rumen fluid of a yellow cow (Bos indicus). This fungus appears to be a previously undescribed species of the genus Caecomyces, it possessing uniflagellate zoospores, a spherical holdfast, tubular sporangiophores and bulbous rhizoids. This new fungus also features distinctive multisporangiate thallus sympodially distributed on sporangiophores. The fungus resembles Caecomyces communis and C. equi in that it characterizes bulbous rhizoids and uniflagellate zoospores but differs from C. communis and C. equi in that it possesses multisporangiate and sympodial sporangia. This new fungus and Cyllamyces aberensis both reveal similar morphology during early thallus development in having a spherical holdfast, but they vary from unbranched sporangiophores and additional bulbous rhizoids. In addition, the molecular phylogenetic analyses ITS1 (internal transcribed spacer 1) also conform to the results of the morphological examinations of Caecomyces. For the mentioned reasons, this new species of fungus is described as Caecomyces sympodialis sp. nov. The genera of Neocallimasticaceae and species of Caecomyces are also keyed out.
