Evaluation of Taxonomic Characters in the Genus Conidiobolus, with Key to Known Species

Abstract

Among the vegetative characters, the diameter and shape of the hyphae are characteristic. The conidlophore is an undifferentiated hyphal branch and this character separates Conidiobolus from Entomophthora. The size of the primary conldia for each species is fairly constant, while secondary conidla formed through repetitional development are progressively smaller in size. The development of microconidia on short sterigmata is of taxonomic importance. Occasionally sterile sterigmata remain as villous structures on conidial surface. While the elongate ellipsoid secondary conldia borne on filamentous conidiophores are produced at random and have no taxonomic significance, the secondary conidia formed in C. erymitus and C. couchil, which are almond-shaped and forcibly discharged, are distinctive. The presence or absence of zygospores in a species can be used for broadly grouping Conidiobolus species as zygosporic and nonzygosporic species. Zygospores are either smooth or undulated. In some species, chlamydospores are present. Three new spp., C. macrosporus, C. bangalorensis and C. nodosus are described.