Silurian brachiopods with soft-tissue preservation

Area of Science:

• Paleontology
• Invertebrate Paleobiology
• Evolutionary Biology

Background:

• Articulated rhynchonelliformean brachiopods are common fossils, but their soft-part anatomy is poorly understood.
• Existing knowledge relies on analogies with modern species, which are untested for early brachiopod groups.
• The Silurian Herefordshire Konservat-Lagerstätte offers exceptional 3D preservation of ancient marine life.

Observation:

• A exceptionally preserved, three-dimensional stem-group rhynchonelliformean brachiopod from the Herefordshire Lagerstätte.
• Fossils are preserved as calcitic void infills within carbonate concretions.
• Digital reconstruction allowed detailed analysis of soft-tissue structures.

Findings:

• A robust, ridged pedicle with rootlets and a lophophore were identified in the specimen.
• The unique pedicle morphology differs significantly from modern brachiopods.
• Associated smaller brachiopods, including an atrypide with preserved pedicle and setae, were also found.

Implications:

• This finding provides direct evidence of soft-tissue anatomy in early brachiopods.
• The novel pedicle structure necessitates caution when inferring extinct brachiopod anatomy from modern relatives.
• The exceptional preservation offers new insights into Silurian marine ecosystems and brachiopod palaeobiology.