''Heightingtonaspis'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of primitive

arthrodire Arthrodira (Greek for "jointed neck") is an Order (biology), order of extinct armored, jawed fishes of the class Placodermi that flourished in the Devonian period before their sudden extinction, surviving for about 50 million years and penetratin ...

placoderm Placoderms (from Ancient Greek πλάξ 'plax'', ''plakos'''Plate (animal anatomy), plate' and δέρμα 'derma'''skin') are vertebrate animals of the class (biology), class Placodermi, an extinct group of prehistoric fish known from Pal ...

fish from the

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

period in

Great Britain Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European ...

, and currently contains three species. The

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

''Heightingtonaspis anglica'' was described by

Ramsay Traquair Ramsay Heatley Traquair Fellow of the Royal Society of Edinburgh, FRSE Fellow of the Royal Society of London, FRS (30 July 1840 – 22 November 1912) was a Scottish naturalist and palaeontologist who became a leading expert on fossil fish. Tra ...

in 1890, and was initially named ''

Phlyctaenius ''Phlyctaenius'' is an extinct genus of placoderm fish, which lived during the Devonian period of New Brunswick, Canada. It was named by Traquair (1890)Traquair, R. H. (1890a). Notes on the Devonian fishes of Seumenac Bay and Campbelltown in Can ...

anglicus''. The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

specimen

NHMUK The Natural History Museum in London is a museum that exhibits a vast range of specimens from various segments of natural history. It is one of three major museums on Exhibition Road in South Kensington, the others being the Science Museum and ...

PAL PV P 29417 was first discovered on the surface at the

Old Red Sandstone Old Red Sandstone, abbreviated ORS, is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the eastern seaboard of North America. It ...

supergroup,

Shropshire Shropshire (; abbreviated SalopAlso used officially as the name of the county from 1974–1980. The demonym for inhabitants of the county "Salopian" derives from this name.) is a Ceremonial counties of England, ceremonial county in the West M ...

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

and the fossils were

radiocarbon date Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The method was de ...

d ''

in situ is a Latin phrase meaning 'in place' or 'on site', derived from ' ('in') and ' ( ablative of ''situs'', ). The term typically refers to the examination or occurrence of a process within its original context, without relocation. The term is use ...

'' to 416 million years old.Robert Denison. (1978). Placodermi. In H.-P. Schultze (ed.), ''Handbook of Palaeoichthyology'' 2:1-128Dineley D. L., Metcalfe S. J. (1999). Chapter 4. Early Devonian fossil fishes sites of the Welsh Borders, Fossil Fishes of Great Britain, 2731White, E.I. (1969). The deepest vertebrate fossil and other arctolepid fishes. ''Biological Journal of the Linnean Society'' 1(3): 293-310 it has also been found in the

Senni Beds Senni may refer to: *Lorenzo Senni (born 1983), Italian musician and visual artist *Manuel Senni (born 1992), Italian cyclist *Afon Senni, a river in Wales {{disambiguation, surname ...

Wales Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...

. ''Heightingtonaspis clarkei'' was described by Charles R. Eastman in 1907, and was originally named ''

Kujdanowiaspis ''Kujdanowiaspis'' is an extinct genus of arthrodire placoderm fish from the Early Devonian of Podolia (Ukraine), Poland and Spain. ''Kujdanowiaspis'' is known from many fragmentary head shields and body armours. Classification ''Kujdanowiaspis ...

clarkei''. It was later revised and reassigned to the genus ''Heightingtonaspis'' by Denison in 1978. ''Heightingtonaspis willsi'' was described by White in 1961, and was originally named ''Kujdanowiaspis willsi'', but was later reassigned to the genus ''Heightingtonaspis'', which was created in 1969 by White. ''H. willsi'' was discovered in the same location as ''H. anglica'', in

. ''Heightingtonaspis'' is one of the more basal members of the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Arthrodira Arthrodira (Greek for "jointed neck") is an order of extinct armored, jawed fishes of the class Placodermi that flourished in the Devonian period before their sudden extinction, surviving for about 50 million years and penetrating most marine eco ...

, as shown in the

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

below:

References

Placoderms of Europe Placoderms Fossil taxa described in 1969 {{placoderm-stub