[1] Rhyniognatha is known from a partial head with preserved mouthparts from the Early Devonian aged Rhynie chert around 400 million years ago, when Earth’s first terrestrial ecosystems were being formed.

The head part of a specimen, preserved in a fragment of Rhynie Chert, was collected in 1919 by the Reverend W. Cran, who provided it to S. Hirst, Samarendra Maulik and D.J.

Several other pieces, including the Rhyniognatha head, were also described as "supposed larval insect" though yet unnamed.

Scourfield to the Natural History Museum in London where it is currently displayed on a microscope slide.

[5] Nevertheless, a detailed reanalysis by Carolin Haug & Joachim T. Haug in 2017 came to a different interpretation, concluding that the identity of Rhyniognatha hirsti as a myriapod, specifically a scutigeromorph centipede, was better supported by the available evidence, without being able to exclude an insect identity completely.