Exechonella Canu & Bassler in Duvergier, 1924

Cáceres-Chamizo, Julia P., Sanner, Joann, Tilbrook, Kevin J. & Ostrovsky, Andrew N., 2017, Revision of the Recent species of Exechonella Canu & Bassler in Duvergier, 1924 and Actisecos Canu & Bassler, 1927 (Bryozoa, Cheilostomata): systematics, biogeography and evolutionary trends in skeletal morphology, Zootaxa 4305 (1), pp. 1-79 : 5

Genus Exechonella Canu & Bassler in Duvergier, 1924

Type species: Cyclicopora ? grandis Duvergier, 1921 Diagnosis. Colonies encrusting, predominantly unilaminar, but becoming bi- and multilaminar or erect in some species. Zooids large (length 0.6–1.6 mm), convex, oval or hexagonal, separated by deep grooves. Peristome from low, collar-like, to long, cylindrical. Primary orifice rounded or oval, often with angular poster and with inner lamina underlaying the anter wall and typically ending with paired condyles—lateral or distolateral. Frontal shield umbunuloid with numerous foramina, opened or covered with an external cuticular layer. Marginal pores always present around zooidal periphery, though not always obvious. Vertical zooidal walls (lateral and transverse) wide or narrow, represented by multiporous mural septula with communication pores arranged in one or several rows. Adventitious avicularia generally present, being associated with lateralmost foramina, which are often larger than the rest of the foramina. Avicularia predominantly oval or round, with a small opening in the nipple or button-like central part but, occasionally, triangular in shape with a cross-bar. Some species have adventitious kenozooids, with a porous frontal wall, that are often associated with lateral avicularia. No ovicells, embryos are incubated in the internal brood sacs. Ancestrula is autozooidal in shape.