''Pustula'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of brachiopods which lived during the

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ...

period. It is the type genus of the subfamily Pustulinae. Its fossils have been found in

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...

, North America and northern Africa.

Description

Members of the genus ''Pustula'' had a subrectangular outline with a weak ventral sulcus, minimal trails and dorsal median folds. Like other echinoconchids, they had recumbent spines arranged in irregular concentric bands, with ''Pustula'' having elongated spine bases and weak spine differentiation. The dorsal face of this brachiopod was trifid, and the cardinal process was narrow. Marginal ridges and cardinal process pits are absent in this genus, while the cardinal ridges diminished towards the ears.

Classification

Brunton et al. (1995) deemed ''Pustula'' to be a primitive member of the Echinoconchidae family, a placement also supported by Muir-Wood & Cooper (1960). Leighton & Maples (2002) conducted multiple phylogenetic analyses which are strongly in agreement that the four subfamilies Buxtoniinae, Echinoconchinae, Pustulinae and Juresaniinae form the family Echinoconchidae. The cladogram results of their phylogenetic analyses are displayed in the cladogram below:

References

{{Taxonbar, from=Q122828027 Rhynchonellata