Genus Chazydictya Ross, 1963

TYPE SPECIES. — Chazydictya chazyensis Ross, 1963 by original designation. Darriwilian, Ordovician ; New York, United States .

DIAGNOSIS. — Bifoliate lenticular, branched colonies. Branch transverse section lens-shaped. Autozooecia short, tubular, recumbent at their bases in endozone, bending sharply to colony surface, rectangular to subrhomboidal at their bases, becoming oval at branch surface, arranged in 8 to 15 regular alternating rows on branches. Hemisepta absent. Basal diaphragms rare to common. Mesotheca straight to weakly undulating, two-layered, without median rods. Autozooecial walls granular, in endozone; thick, finely laminated in exozone. Paurostyles in the laminated skeleton abundant, arranged in up to 5 rows between autozooecial apertures, rounded to weakly stellate in tangential section. Maculae absent.

OCCURRENCE. — Darriwilian, Ordovician; United States, Canada. Sandbian, Ordovician; Argentina.

COMPARISON

Chazydictya Ross, 1963 differs from Ptilodictya Lonsdale, 1839 in absence of hemisepta and presence of abundant paurostyles.