In the late 20th and early 21st century, the family Isididae (i. e. Isididae
sensu lato or "in the broad sense") In 2016, it was proposed that the above subfamilies be elevated to the following families: • Isididae
sensu stricto or "in the stricter sense" (containing only the genus
Isis), •
Keratoisididae, •
Mopseidae •
Circinisidae. The genera
Chelidonisis and
Murcellisis were deliberately not included in Isididae
sensu stricto, with
Chelidonisis now being left unassigned to a family and
Murcellisis being considered
incertae sedis within
Octocorallia, with an unclear relationship. In 2021, the 2016 proposal was partly modified, yielding the following currently accepted families: • Isididae
sensu stricto (containing only the genus
Isis) [corresponds to former Isidinae minus
Chelidonisis] •
Chelidonisididae (containing only the genus
Chelidonisis) •
Keratoisididae [corresponds to former Keratoisidinae] •
Mopseidae [corresponds to former Mopseinae and Circisidinae]. The Muricellisidinae were removed in this new system, because in 2020, the genus
Mucellisis (and thus also the subfamily Muricellisidinae) was found not to exist, given that the only two species it consisted of actually belong to the genera
Anthothela (in the family
Anthothelidae) and
Melitheae (in the family
Melithaeidae), and thus were moved to these genera. In 2022, the genera
Hicksonella and
Rumphella, which until then had been included in the family
Gorgoniidae in the former order
Holaxonia, were moved to Isididae
sensu stricto. Therefore, the family Isididae (i. e. Isididae
sensu stricto) currently contains only the genera
Isis,
Hicksonella and
Rumphella. The following
cladogram is based on a
maximum likelihood phylogenetic tree, using samples of
Ultra-Conserved Elements (UCE) and
Exonloci, from a study by McFadden, Ofwegen, Quattrini (2022), with the taxa historically placed within Isididae being
bolded: }} ==References==