Inoceramus (Inoceramus) cuvierii

Overview

Inoceramus cuvierii is a Cretaceous bivalve distinguished by broad, low concentric folds. Its thick shell is described as flat or slightly convex. There is much to discover by examining both the overall outline and the fine growth lines.^[1]

Key facts

Its shell outline is difficult to represent with a single geometric shape. The species description includes forms ranging from nearly triangular to nearly rectangular. This shows how comparisons of fossils bearing the same name also consider the range of variation across specimens.^[1]

Time and place

A 2012 study examined Middle Turonian material from the Stara Bystrzyca quarry in present-day southwestern Poland. These are Late Cretaceous fossils; the Cretaceous as a whole spans roughly 140–66 million years ago. The study examined traces of ancient bivalves in limestone exposed in the present-day quarry.^[1][2]

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

Size, form and skeleton

Broad, low folds run concentrically across a thick, flat or slightly convex shell. Finer growth lines lie between the large folds. Distinguishing the overall outline from surface traces of different sizes makes its features easier to read.^[1]

Habitat and reproduction

The hard shell that enclosed the body preserves its outer outline and traces of growth. The description of this species compares thickness, convexity, and the arrangement of folds together. Following small traces across the broad surface reveals a shell as more than a simple plate.^[1]

Fossil discovery

Chrząstek's 2012 study presented numbered specimens together with descriptions of their form. MGUWr5455s–5457s are specimens presented as belonging to the same species. This is an example of establishing a species' features through comparisons of several fossils rather than a single representative shape.^[1]

References

1. Chrząstek (2012) — Turonian Inoceramus from Poland
2. International Commission on Stratigraphy (2024) — Geological time chart
3. García-Barrera (1995) — Toucasia from southwestern Mexico

Research questions

How can low folds be distinguished from fine growth lines? First locate the broad, wave-like features, then examine the fine lines between them. Reading the overall body outline together with detailed surface structures helps in identifying fossils.^[1]

Observation

Look at the broad, flat outline, then follow the low concentric folds. Finding the fine lines between the large folds distinguishes surface traces of different sizes.^[1]