Verticils of Annularia are usually found as dorsi-ventral adpressions spread out on the bedding plane; leaf whorls in Annularia are either isophyllous or markedly anisophyllous. In contrast, the leaves of Asterophyllites are usually preserved flattened sideways, parallel to the axis.
The late Stephanian Annularia spinulosa has longer, anisophyllous, lanceolate leaves (at 27-45 mm length, more than double the length of those of Annularia fertilis), with the greatest width just above the middle, and a sharply pointed apex.
Matthew's variety was considered by Bell (1944) to fit the range of leaf length of Annularia latifolia; however, the verticils of the latter are anisophyllous and its leaves are widest in their upper third.