title: A larval Devonian lungfish.
abstract: Perhaps the most enduring of puzzles in palaeontology has been the identity of Palaeospondylus gunni Traquair, a tiny (5-60-mm) vertebrate fossil from the Middle Devonian period (approximately 385 Myr ago) of Scotland, first discovered in 1890 (refs 1-3). It is known principally from a single site (Achanarras Quarry, Caithness) where, paradoxically, it is extremely abundant, preserved in varved lacustrine deposits along with 13 other genera of fishes. Here we show that Palaeospondylus is the larval stage of a lungfish, most probably Dipterus valenciennesi Sedgwick and Murchison 1828 (ref. 5), and that development of the adult form requires a distinct metamorphosis. Palaeospondylus is the oldest known true larva of a vertebrate.
authors.affiliation: Oxford University Museum of Natural History, Parks Rd, Oxford OX1 3PW, UK. keith.thomson@university-museum.oxford.ac.uk
authors.forename: Keith S
authors.initials: KS
authors.lastname: Thomson
authors.forename: Mark
authors.initials: M
authors.lastname: Sutton
authors.forename: Bethia
authors.initials: B
authors.lastname: Thomas
mesh_terms: D000818:Animals; D005580:Fossils; D007814:Larva / Q000033:anatomy & histology* / Q000145:classification* / Q000254:growth & development; D008675:Metamorphosis, Biological; D012863:Skeleton; D014714:Vertebrates / Q000033:anatomy & histology* / Q000145:classification* / Q000254:growth & development