Palaeobotany

Diversity of life

Rediscovering plants from a lost landscape

Plants are an essential part of the Angeac deposit. Their remains reveal a site inhabited by much more than dinosaurs and help reconstruct the landscape in which those animals lived.

Reconstruction of conifers. © Mazan. Dinosaures, les géants du vignoble, 2017, pp. 146–147.

The method in practice

Palaeobotany studies fossil plants: wood, leaves, twigs, cones, seeds and other structures. Researchers compare shapes and tissue organisation, sometimes using electron microscopy. They also investigate whether organs found separately belonged to the same plant.

At Angeac and in regional comparisons

Angeac yields trunks, sometimes associated with stumps or roots, together with leafy shoots, cones and conifer seeds. Agathoxylon wood, Watsoniocladus shoots and Classopollis pollen provide complementary evidence of vegetation. Linking separate organs to the same plant requires anatomical and stratigraphic evidence.

A major discovery · 2023

A 14.54-metre fossil tree

With preserved roots and almost fifteen metres in length, this trunk brings the forest that occupied Angeac about 140 million years ago into focus. Excavated during the 2023 campaign, it is identified by the Centre de recherche en paléontologie de Paris as the largest fossil unearthed at the site since excavation began.

This conifer belongs to the extinct family Cheirolepidiaceae. The preserved length does not represent the tree’s full height: its top is missing.

A large conifer trunk excavated at Angeac-Charente. © V. Réneleau.

Aerial view of the Angeac-Charente excavation during the exposure of a large fossil trunk, 2023. © Ludovic Royer.

Discovery, photographs and moulding: CR2P–MNHN, 31 July 2023 ↗

Ferns, conifers and other plants

The vegetation is reconstructed at several scales. Trunks, twigs, leaves, cones and seeds reveal plants visible in the landscape, while pollen and spores also reveal microscopic diversity. These two records complement each other, but do not represent plants in the same proportions.

Conifers dominate the larger plant remains

Plant remains from Angeac indicate local vegetation dominated by conifers of the extinct family Cheirolepidiaceae. The remains include wood assigned to Agathoxylon, Brachyphyllum shoots and leaves, and cones and seeds preserved in three dimensions. Some trunks remain associated with their roots or branches.

These names sometimes describe fossil organs studied separately. A name given to wood and another given to foliage do not automatically mean two different tree species. Reconstructing a whole plant from these organs requires comparisons of anatomy and context.

Ferns and their spores

Fern frond and stem fragments are rarer than conifer remains. Spores add to the picture: the study by Polette, Batten and Néraudeau published in 2018 distinguishes 34 palynomorph species in the samples studied. Fern spores include Concavissimisporites and Trilobosporites; Classopollis dominates the gymnosperm pollen.

Other microremains indicate lycophytes, liverworts and freshwater algae. Charophytes have their own page. Living horsetails and ginkgo reconstructions serve as botanical comparisons: illustrating them does not establish the presence of each plant at Angeac.

Pollen and spores from Angeac, views A–P. Scale bar: 10 µm. Polette, Batten & Néraudeau, 2018, fig. 4.

Palynological composition of units An2–An4. Counts per sample, not a direct measurement of the area covered by plants. Polette, Batten & Néraudeau, 2018, fig. 7.

Examining a spore, reading a landscape

Size, outline and wall ornamentation help researchers compare spores. Some bear small warts; others have a network pattern. Megaspores are larger spores, distinct from seeds. Microscopy reveals wall details that help describe and identify them.

Explore the five additional plates

Characters measured on a spore to compare its morphology. Polette, Batten & Néraudeau, 2018, fig. 2.

Spores of the genus Concavissimisporites. Scale bar: 10 µm. Polette, Batten & Néraudeau, 2018, fig. 5.

Spores of Concavissimisporites and Trilobosporites. Scale bar: 10 µm. Polette, Batten & Néraudeau, 2018, fig. 6.

Erlansonisporites megaspores and wall details. Scale bars: A, E, 200 µm; B, 50 µm; C, 10 µm; D, 5 µm; F, 20 µm. Polette, Batten & Néraudeau, 2018, fig. 10.

Megaspores and detailed scanning electron microscope views. Scale bars: A, C, E, 200 µm; B, D, F, 20 µm. Polette, Batten & Néraudeau, 2018, fig. 11.

Pollen and spore proportions depend on production, transport and preservation. They cannot be converted directly into tree numbers or fern cover. Comparing these microremains with wood, leaves and sediments refines the reconstruction of the landscape.

The 2018 palynological study helped revise the site’s age to the Berriasian–Valanginian. The 2022 synthesis adopts a Berriasian age. Dates and environmental interpretations must therefore be read in the context of the knowledge available when each study was published.

Polette, Batten & Néraudeau, 2018: study and figures ↗ · Allain et al., 2022: vegetation and environment, pp. 735–736 ↗

Understanding palynology → · Charophytes →

What this research reveals

Leaves, wood, seeds and reproductive organs are often found separately. Anatomical study links these remains and progressively reconstructs Angeac’s plants and vegetation.

People and expertise

Véronique Daviero-Gomez and Bernard Gomez contribute expertise in fossil plants and ancient vegetation. This research links plant organs, their anatomy and their discovery context.

Véronique Daviero-Gomez Bernard Gomez

All the people behind the project →