ACTINOSTOLIDAE CARLGREN, 1932

Gusmão, Luciana C. & Rodríguez, Estefanía, 2021, Two sea anemones (Cnidaria: Anthozoa: Actiniaria) from the Southern Ocean with evidence of a deep-sea, polar lineage of burrowing sea anemones, Zoological Journal of the Linnean Society 193, pp. 1392-1415 : 1397

FAMILY ACTINOSTOLIDAE CARLGREN, 1932

Diagnosis (after Rodríguez et al. (2008) with modifications in italics). Enthemonae with basilar muscles and mesogleal marginal sphincter; column commonly smooth, rarely tuberculate or with papillae. Tentacles regularly arranged; their aboral sides sometimes with nematocysts batteries, sometimes thickened. Mesenteries not divisible into macro- and microcnemes. Younger mesenteries not bilaterally arranged. Retractor muscles diffuse, rarely circumscribed. No acontia. Cnidom: gracile spirocysts, basitrichs and b -mastigophores and p -mastigophores A.

Type genus: Actinostola Verrill, 1883 .

Other valid genera: Antholoba Hertwig, 1882 (?); Anthosactis Danielssen, 1890 ; Antiparactis Verrill, 1899 ; Bathydactylus Carlgren, 1928 ; Chitinactis ; Cnidanthus Carlgren, 1927 ; Glandulactis Riemann- Zürneck, 1978; Hadalanthus ; Hormosoma ; Ophiodiscus Hertwig, 1882 ; Paranthus Andres, 1883 (?); Parasicyonis Carlgren, 1921 ; Pseudoparactis Stephenson, 1920 ; Pycnanthus McMurrich, 1893 ; Sicyonis ; Stomphia ; Synsicyonis Carlgren, 1921 ; Tealidium Hertwig, 1882 .

Remarks: We follow the circumscription given by Rodríguez et al. (2008) for Actinostolidae , except for the addition of genus Glandulactis to the family and removal of Cnidanthea Carlgren, 1959 now included in the family Isanthiidae Carlgren, 1938 (Metridioidea) following Fautin (2016). The question mark after genera Antholoba and Paranthus reflects the uncertainty in their taxonomic placement due to every molecular phylogenetic analysis to date placing them within the superfamily Metridioidea (e.g. Lauretta et al., 2014; Rodríguez et al., 2014; Grajales & Rodríguez, 2016; Gusmão et al., 2018, 2019, 2020). The diagnosis of Actinostolidae was not required to be modified by the inclusion of the new genus Chitinactis .