Longisquama

Longisquama is a genus of extinct reptile containing only one species, L. insignis, known from a poorly preserved skeleton and several incomplete fossil impressions from the Middle to Late Triassic Madygen Formation of Kyrgyzstan. The generic name means "long scales", and the specific name insignis means "unusual", in Latin. The holotype is notable for a number of long feather-like structures growing from its back. The affinities of Longisquama among reptiles have long been contentious, with some researchers controversially connecting Longisquama and its back structures to the origin of birds and feathers, a view which is largely rejected. In 2025, a close relative, Mirasaura was described from France, which shares the feather-like back structures. Phylogenetic analysis of Mirasaura suggests that it and by extension Longisquama belong to Drepanosauromorpha.

==History== The holotype specimen, PIN 2584/4, was discovered by A.G. Sharov while he was searching for Triassic insect fossils in the Leylek District in Kyrgyzstan. The specimen was recovered from rocks of the Madygen Formation, at the Djailaucho locality. Four other specimens, each preserving 1-6 "long scales" in isolation, were designated as paratypes. These specimens are all in the collection of the Paleontological Institute of the Russian Academy of Sciences in Moscow. Three additional isolated integumentary structures, in the collections of the Geological Institute of the Freiberg University of Mining and Technology, were recovered from the locality in 2007.