Article: Late Triassic ecosystems of the Molteno/Lower Elliot biome of southern Africa

A first attempt is made to integrate the plant, insect and tetrapod elements of the Late Triassic (Carnian) intracontinental, braidplain ecosystems of the Karoo Basin, South Africa. These are probably the richest known for this pivotal early Mesozoic interval when the dinosaurs, mammals, some insect orders and possibly the birds and flowering plants made their earliest appearance. Intensive sampling of 100 Molteno Formation taphocoenoses has yielded 56 genera with 206 species of plant (vegetative taxa) and 117 genera with 335 species of insect. Seven major habitats are identified and described, ranging from two types of riparian forest through open woodland to coniferous thicket, horsetail marsh and fern meadow. Each shows a distinctive plant/insect co-association. The tetrapod-vertebrate component of these associations is based on the Lower Elliot Formation, the assumed distal facies and time equivalent of the upper four members of the Molteno Formation. This is a sparse (seven taxa) early dinosaur fauna including both body fossils and trackways. The Upper Elliot Formation has a richer tetrapod fauna and may, in future, be used to model possible missing elements of the Lower Elliot Formation. Comparison of the Molteno insect fauna with that of two other Carnian deposits, in Australia (Ipswich Basin) and North America (Newark Basin), reveals marked provinciality reflecting temperate and tropical latitudes.