@article{mbs:/content/journal/ijsem/10.1099/00207713-34-4-465, author = "Starr, Mortimer P. and Short, Kevin A. and Schmidt, Jean M.", title = "Exclusion of the Filamentous and Rosette-Forming Bacterium “Planctomyces gracilis” Hortobágyi 1965 from the Blastocaulis-Planctomyces Group", journal= "International Journal of Systematic and Evolutionary Microbiology", year = "1984", volume = "34", number = "4", pages = "465-469", doi = "https://doi.org/10.1099/00207713-34-4-465", url = "https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/00207713-34-4-465", publisher = "Microbiology Society", issn = "1466-5034", type = "Journal Article", abstract = "The transient occurrence during the summer of 1982 of “Planctomyces gracilis” Hortobágyi 1965, originally described as a planktonic fungus, in two eutrophic man-made ponds in Tempe, Ariz., provided the first recorded sightings of this unusual organism in the United States. A comparison of phase-contrast micrographs prepared from Arizona material with archival descriptions and sketches showed agreement in all respects. Transmission electron microscopy suggested that “P. gracilis” is a bacterium rather than a fungus. Notable differences in several traits serve to exclude “P. gracilis” from the Blastocaulis-Planctomyces group of budding and nonprosthecately appendaged bacteria. There was no evidence of multifibrillar appendages or crateriform surface structures in “P. gracilis”; these are major defining characteristics of the Blastocaulis-Planctomyces group. “P. gracilis” is a filamentous and rosette-forming bacterium of unknown taxonomic position.", }