1999/06/14 by Adam M. Yates · 7 citations
Earth and Planetary Sciences · #Paleontology and Evolutionary Biology #Evolution and Paleontology Studies #Paleontology and Stratigraphy of Fossils
paper · doi:10.1080/02724634.1999.10011143
openalex publication_date 1999/06/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
New material from the Arcadia Formation (Rewan Group) of Queensland is referred to the small temnospondyl Lapillopsis nana. This species is redescribed and its systematic position is reconsidered. Originally described as a dissorophoid, L. nana lacks most of the synapomorphies that diagnose the Dissorophoidea, such as a laterally exposed palatine, a dorsal process on the quadrate, and a ventral nasal flange. Instead, it possesses synapomorphies which diagnose the Stereospondyli or more inclusive clades, such as ornamented pterygoids, a pterygoid-parasphenoid articulation that sutures early in ontogeny, a postglenoid area on the mandible, and lacrimals that are excluded from both the orbital and narial margins. Rotaurisaurus contundo gen. et sp. nov. is described from the Knocklofty Sandstone of Tasmania, based on a specimen that was first identified as a juvenile lydekkerinid. It shares with Lapillopsis nana an unusual tabular horn morphology and a narrow pterygoid-parasphenoid articulation, as well as a similar combination of derived and plesiomorphic characters. The two taxa together form the Lapillopsidae fam. nov., a family of basal stereospondyls. Lapillopsids may have filled a semiterrestrial dissorophoid-like niche in the Early Triassic of Gondwana.