Fossil insect eggs on Lower Jurassic plant remains from Bavaria (Germany)

Imprints of fossil insect eggs (oviposition slits of endophytic eggs) on Lower Jurassic plants from Franconia (Bavaria, Germany) are described. Two forms can be distinguished. Form A (2.5–3 mm long, 0.5–0.7 mm wide) is comparable to Hysterites friesii Nathorst 1876, who described it on Podozamites leaves (Coniferales) and considered it to be fungal remains. The present oviposition slits are, however, all on Schmeissneria microstachys leaves (Ginkgoales), and are therefore not considered to be conspecific with Nathorstʹs species. Form B (ca. 2 mm long, 0.7 mm wide) is more rare, and has only been found on Podozamites distans leaves but cannot be identical with Nathorstʹs material because they demonstrate a different shape. Form A has been deposited by dragonflies (Odonata); the insects that deposited form B may also have belonged to this group but this cannot be said with certainty. Comparison with other fossil insect egg/plant relationships are made, e.g. with comparable eggs on Triassic material of Equisetites arenaceus. The parent plants must have lived in an aquatic, or more probably semi-aquatic environment.