Phillips's fan-maidenhair tree (Baiera phillipsi)

Baiera phillipsi - Jurassic Ginkgophyte Fossil Species

Discovered in the famous Jurassic plant beds of Yorkshire, Baiera phillipsi commemorates the pioneering work of geologist John Phillips. This extinct gymnosperm represents a highly diverse lineage of plants that dominated the mid-Mesozoic landscape. Its fossils are typically found in fine-grained sandstones that preserve fine details of the leaf architecture.

The species thrived in coastal delta environments during a period of warm and humid climates. It played a major role in the understory vegetation of ancient gymnosperm forests.

Taxonomy

Morphology

The morphology of this fossil species is characterized by medium-sized, fan-shaped leaves with multiple levels of division. The leaf blade splits close to the base into several primary segments, which then branch dichotomously two or three times. This branching pattern creates a broad, fan-like canopy for each leaf.

Key morphological features include:

  • Dichotomous branching: The leaf segments split symmetrically at regular intervals, producing a regular, nested appearance.
  • Flattened petiole base: The base of the leaf expands gradually into the stem attachment, lacking a sharp boundary.
  • Parallel veins: Multiple parallel veins run through each lobe, providing structural support to the thin leaf tissue.

The stomata are situated in distinct bands between the veins on the lower leaf surface. This arrangement helped the plant regulate gas exchange in environments with fluctuating water tables.

Applications

Fossil specimens of this species are primarily used for evolutionary research into the early diversification of ginkgophytes. They help paleontologists trace how leaf shapes adapted to changing light levels in Jurassic forests.

They also serve as important reference fossils for geological mapping in the British Isles and Western Europe.

Interesting facts

This species was named in honor of John Phillips, who was one of the first scientists to systematically map the geology of Yorkshire in the nineteenth century. His work laid the foundation for modern biostratigraphy.

Unlike modern Ginkgo biloba leaves, which are usually single-lobed or double-lobed, this species had leaves that resembled small fan-like hands with multiple narrow fingers. This shape may have helped the plant shed heavy rain more efficiently.

Geography of distribution

  • United Kingdom

Sources

  • GBIF Backbone Taxonomy: Baiera phillipsi record (gbif.org)
  • The International Fossil Plant Names Index (IFPNI): Taxonomic records of Baiera