The Rhynie Chert is an early Devonian (Pragian Age – about 412 to 400 million years ago) konservat Lagerstätte located in Aberdeenshire, Scotland, some 50 km west of Aberdeen. This fossil site is a petrified peat bog preserving primitive plants and animals in exquisite detail. The fossils enable the study of the early terrestrial ecosystems. During the early Devonian, the site was part of Larussia, a continent that included what is now North America, Greenland, Scotland, England and Whales, located about 28 degrees below the equator.

The fossils were formed in a swampy peat bog of a tropical to subtropical environment where plant tissues were preserved through rapid silicate diagenesis. The remarkable plant fossil preservation retains the structure of individual cells, thereby providing detailed scientific data regarding the rapid adaptation and early colonization of the land by plants. Besides primitive plants, the Rhynie Chert has yielded of algal, fungi, and prokaryotic bacteria fossils as well as a diversity of early terrestrial arthropods such as Myriapods (millipedes and centipedes), Collembola, and Arachnids such as Opiliones (harvestmen), pseudoscorpions and the extinct, spider-like trigonotarbids.

One of the more interesting arthropods of the Rhynie Chert is the primitive, extinct Arachnids of Order Trigonotarbida. The Trigonotarbids have a fossil record extending from the Silurian to the Lower Permian and are known from several localities in Europe and North America. Like their closely related spider relatives they had eight legs and a pair of pedipalps. These oldest known terrestrial arthropods are believed to have stalked their prey on the ground, and apparently lack silk and poison glands.

References: