Teratology and pathology of some Paleozoic conulariids

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Abstract
Conulariids exhibiting various pathologies and teratological conditions have been examined from Paleozoic rocks of North America, South America, Europe, and Africa. Published examples of teratological conditions in conulariids have been reviewed. To these cases we add a specimen of Paraconularia missouriensis (Swallow) from the Mississippian of Ohio [USA] which possesses six faces. The supposed three-sided conulariid species Conularina triangulata (Raymond) is tested upon a specimen which is not a conulariid. This genus is removed from the phylum Conulariida and is considered incertae sedis. Pathologies included injuries to the exoskeleton which are grouped into pattern termed scalloped, cleft, and embayed. Scalloped injuries represent minor chipping at the aperture of the conulariid exoskeleton, and may have occurred accidentally or through predation. Cleft and embayed injuries, found only on post-Silurian taxa, indicate that conulariids suffered severe sublethal attacks more frequently after the rise of several types of durophagous predators in the middle Paleozoic. Some middle and late Paleozoic conulariid species strengthened the exoskeleton, perhaps to resist predation. Regeneration of injured integument of rods has occurred in conulariids exhibiting damaged exoskeletons.