anaeroplasmatales anaeroplasmatales anaeroplasmatales is an order of mollicute bacteria which are generally found in the rumens of cattle and sheep. the only family in the order is the family anaeroplasmataceae. anaeroplasmatales scientific classification domain: bacteria phylum: mycoplasmatota class: mollicutes order: anaeroplasmatalesrobinson & freundt 1987 family: anaeroplasmataceaerobinson & freundt 1987 families and genera anaeroplasma asteroleplasma "ca. avacholeplasma" "ca. pelethenecus" description members of the order anaeroplasmatales can appear as different shapes at different times in their lifecycles. cells which are 16–18 hours old tend to be spherical. when the cells are older, they can take on various shapes. anaeroplasmatales are not motile. anaeroplasmatales cannot grow in the presence of oxygen. they do grow at a temperature of 37 °c on microbiological media, where they form irregular-shaped colonies with a "fried-egg" appearance, similar to other mycoplasmas. anaeroplasmatales are negative by gram stain. history the order anaeroplasmatales was created in 1987 to encompass the family anaeroplasmataceae which itself was created to hold the anaerobic mycoplasmas anaeroplasma and asteroleplasma. phylogeny the currently accepted taxonomy is based on the list of prokaryotic names with standing in nomenclature (lpsn) and national center for biotechnology information (ncbi) 16s rrna based ltp_12_2021 gtdb 07-rs207 by genome taxonomy database acholeplasmataceae haploplasma alteracholeplasma paracholeplasma acholeplasma anaeroplasma acholeplasmatales uba5453 paracholeplasma acholeplasmataceae anaeroplasmataceae "ca. pelethenecus" gilroy et al. 2021 "ca. avacholeplasma" gilroy et al. 2021 anaeroplasma robinson, allison & hartman 1975