Productus productus

Overview

Productus productus is a brachiopod from Carboniferous seas. Its shell extends far forward from a convex body. A broad hinge and ear-like areas on either side create a distinctive outline.^[1][2]

Key facts

It looks almost as though a flat plate has been attached in front of a rounded body. This contrast is easy to miss when viewing the shell from only one direction. Side and top views reveal the swollen body and the long forward extension.^[1]

Time and place

Its record is associated with the late Visean of the Carboniferous, around 330 million years ago. Brachiopods in those seas displayed a variety of shell forms. Comparing several species from the same time helps us explore ancient seafloors.^[3][1]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

The convex body contrasts with the shape of the long forward extension. On either side of the hinge are widened, ear-like areas. A synthesis of research on the genus compares features on both the outside and inside of the shell.^[1][2]

Habitat and reproduction

Brachiopods are marine animals that filter small food particles from the water. Water entering between the shell valves passes over an internal feeding organ. Their hard shells remained in ancient sediments after these animals lived on the seafloor.^[4]

Fossil discovery

BMNH B40952 is the name-bearing specimen of this species. Later researchers have compared similar fossils with it. Specimens of similar form and the characteristics of Productus were discussed again in 2022.^[1][2]

References

1. Treatise on Invertebrate Paleontology — Productus
2. Carniti et al.2022 — Morphology and comparisons of fossil brachiopods
3. International Commission on Stratigraphy — Geological timescale
4. British Geological Survey — The body and feeding of brachiopods
5. Treatise on Invertebrate Paleontology — Productus
6. Carniti et al.2022 — Morphology and comparisons of fossil brachiopods
7. International Commission on Stratigraphy — Geological timescale
8. Pennsylvanian Invertebrate Fauna — The shell of Composita
9. International Commission on Stratigraphy (2024) — Geological time chart

Research questions

How might the broadly extended front of the shell have helped the animal live? Specimens can be viewed from several directions and compared with other brachiopod bodies. Shell folds and proportions provide clues to relationships and ways of life.^[1][4]

Observation

Follow the shell from the convex body to its long forward extension. Including the ear-like areas on either side of the hinge makes the overall outline easier to understand.^[1]