Piromyces citronii sp. nov., a strictly anaerobic fungus from the equine caecum: a morphological, metabolic, and ultrastructural study

Piromyces citronii sp. nov. was isolated from the caecum of one pony and three donkeys. It differed from other anaerobic fungal species in that it had a filamentous monocentric thallus composed of a globular or elliptic sporangium, which was occasionally bifid or trifid (monocarpic thallus), or several sporangia (polycarpic thallus), with a short sporangiophore. P. citronii also differed from other species in that it did not grow with starch or maltose as carbon source and it did not produce d‐lactate. The uniflagellate zoospores presented a standard ultrastructure.