Abstract
Colatooeciidae includes the genera Colatooecia, Cigclisula and Trematooecia. While Colatooecia is considered a well-defined genus, the differences between Cigclisula and Trematooecia are poorly defined. This taxonomic review was undertaken to understand the morphological differences between Cigclisula and Trematooecia. The type species of Cigclisula is redescribed and the type species of Trematooecia is designated and redescribed. Diagnostic characters of both genera are redefined. Six new species of Cigclisula and one of Trematooecia are described: Cigclisula australis n. sp., Cigclisula buski n. sp., Cigclisula fistulosa n. sp., Cigclisula osburni n. sp., Cigclisula perforata n. sp., Cigclisula winstonae n. sp. and Trematooecia rotunda n. sp. Four species previously assigned to Cigclisula are transferred to Trematooecia: Trematooecia arborescens (Canu & Bassler, 1928) n. comb., Trematooecia gemmea (Winston & Woollacott, 2009) n. comb., Trematooecia hexagonalis (Canu & Bassler, 1930), and Trematooecia verticalis (Maplestone, 1910) n. comb. Two species previously assigned to Trematooecia are transferred to Cigclisula: Cigclisula turrita (Smitt, 1873) and Cigclisula psammophila(Winston & Håkansson, 1986) n. comb.