Family CALLOPORIDAE Norman, 1903

Calloporidae: Gordon, 1984: 26.

As defined by Gordon (1984), the Calloporidae includes a wide range of zooidal morphologies. Autozooids have an extensive membranous frontal wall, although this is often obscured by marginal spines. Interzooidal, vicarious and adventitious avicularia may be present. The ovicell is hyperstomial, and may have one or more entooecial areas exposed frontally.

Both Ryland and Hayward (1977) and Gordon (1984) have emphasized the wide range of characters of the genera they included in this family, which almost certainly requires revision in the future. Both Leptinatella and Bryocalyx differ from other genera in having only one pair of delicate oral spines, or none at all. The colony form, and the ovicells of Bryocalyx are also unlike any other genus of Calloporidae .