Amphibian eggs from the Lower Permian of north-central Texas

Masses of small (up to 0.8 mm in diameter) oviform bodies were found in association with fossil plants as well as freshwater and terrestrial invertebrate and vertebrate remains in the Waggoner Ranch Formation (Wichita Group, Leonardian Series, Lower Permian) of Baylor County Texas; this is the first record of fossilized amphibian eggs. The eggs occur as compact, rounded masses and as irregular sheetlike or unilayered aggregates, some of which cover plant remains to which they may have been attached originally. Individual eggs consist of a compressed central body surrounded by a thin, apparently flexible membrane, and an outermost halolike covering, Characteristics of the egg masses and the morphology of individual eggs are indistinguishable from these of modern anuran amphibians. Because dissorophoid temnospondyls are phylogenetically related closely to Recent amphibians and are well represented in the Lower Permian of north-central Texas, dissorophoids are the most probable sourer of the eggs.