Ortotilan

Ortotilan is a genus of small to medium-sized, non-avian theropod dinosaurs that lived during the Early Cretaceous period, around 145 to 100 million years ago. The first remains of orthotilians were discovered in 1978 in the Tomanivi Formation in Fiji, and since then several species have been described, primarily based on remains found in the Gondwanan supercontinent.

The name Orthotilan is derived from Greek words combining orthos, meaning "straight" or "true", and Tile, possibly referring to a prehistoric site. Fossils of orthotilians have been found in sediments deposited in an island arc environment, which suggests that this group of theropods lived in warm, humid climates with abundant vegetation.

Ortotilan dinosaurs were characterized by their relatively small size, with adults typically measuring from one to two meters in length and weighing approximately two to ten kilograms. They were likely agile predators, feeding on smaller animals and insects, and might have also been omnivorous, as suggested by the presence of coprolites containing plant material. The dental and skeleton characteristics of orthotilians show affinities with more well-known groups of theropods, such as the coelurosaurs.

Ortotilan is significant because it represents a unique example of theropod evolution outside of the commonly studied branches of alvarezsaurids and maniraptorans. Despite the description of several species, there is still much to be learned about the biology and diversity of orthotilians. Further research into their fossil record and ecology may help elucidate the relationships between this group and other theropods, shedding more light on the complexities of the ancient dinosaur world.