An ichnotaxon (plural ichnotaxa ) is "a taxon based on the fossilized work of an organism", i.e. the non-human equivalent of an artifact . Ichnotaxon comes from the Ancient Greek ἴχνος ( íchnos ) meaning "track" and English taxon , itself derived from Ancient Greek τάξις ( táxis ) meaning "ordering".
5-483: Apatopus is an ichnogenus , or a name based on footprints , that may have been from a phytosaur . The trackmaker lived in the early Triassic . It was named by Baird in 1957. Of special relevance in regard to its phytosaurian identity is the fact that the tracks are positioned in a way that indicates that the limbs were held directly under the body, a gait known in true archosaurs like crocodiles and dinosaurs but previously thought absent in phytosaurs. This raises
10-504: The ichnogenus rank, based upon trace fossils that resemble each other in morphology but have subtle differences. Some authors have constructed detailed hierarchies up to ichnosuperclass, recognizing such fine detail as to identify ichnosuperorder and ichnoinfraclass, but such attempts are controversial. Due to the chaotic nature of trace fossil classification, several ichnogenera hold names normally affiliated with animal body fossils or plant fossils. For example, many ichnogenera are named with
15-478: The lifeforms themselves). They are assigned genus and species ranks by ichnologists , much like organisms in Linnaean taxonomy . These are known as ichnogenera and ichnospecies , respectively. "Ichnogenus" and "ichnospecies" are commonly abbreviated as "igen." and "isp.". The binomial names of ichnospecies and their genera are to be written in italics . Most researchers classify trace fossils only as far as
20-479: The question of whereas this trait was shared by the last common ancestor between archosaurs and phytosaurs or if it evolved independently between these groups. This trace fossil -related article is a stub . You can help Misplaced Pages by expanding it . Ichnogenus Ichnotaxa are names used to identify and distinguish morphologically distinctive ichnofossils , more commonly known as trace fossils ( fossil records of lifeforms ' movement, rather than of
25-545: The suffix -phycus due to misidentification as algae. Edward Hitchcock was the first to use the now common -ichnus suffix in 1858, with Cochlichnus . Due to trace fossils' history of being difficult to classify, there have been several attempts to enforce consistency in the naming of ichnotaxa. The first edition of the International Code of Zoological Nomenclature , published in 1961, ruled that names of taxa published after 1930 should be 'accompanied by
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