During the 19th century, in England many fragmentary pterosaur fossils were found in the
Cambridge Greensand, a layer from the early Cretaceous, that had originated as a sandy seabed. Decomposing pterosaur cadavers, floating on the sea surface, had gradually lost individual bones that sank to the bottom of the sea. Water currents then moved the bones around, eroding and polishing them, until they were at last covered by more sand and fossilised. Even the largest of these remains were damaged and difficult to interpret. They had been assigned to the genus
Pterodactylus, as was common for any pterosaur species described in the early and middle 19th century. Young researcher
Harry Govier Seeley was commissioned to bring order to the pterosaur collection of the
Sedgwick Museum in
Cambridge. He soon concluded that it was best to create a new genus for the Cambridge Greensand material that he named
Ornithocheirus (meaning "bird hand"), as he in this period still considered pterosaurs to be the direct ancestors of birds, and assumed the hand of the genus to represent a transitional stage in the evolution towards the bird hand. To distinguish the best pieces in the collection, and partly because they had already been described as species by other scientists. Between the years 1869 and 1870, Seeley each gave them a separate species name:
O. simus,
O. woodwardi,
O. oxyrhinus,
O. carteri,
O. platyrhinus,
O. sedgwickii,
O. crassidens,
O. capito,
O. eurygnathus,
O. reedi,
O. cuvieri,
O. scaphorhynchus,
O. brachyrhinus,
O. colorhinus,
O. dentatus,
O. denticulatus,
O. enchorhynchus,
O. xyphorhynchus,
O. fittoni,
O. nasutus,
O. polyodon,
O. tenuirostris,
O. machaerorhynchus,
O. platystomus,
O. microdon,
O. oweni and
O. huxleyi, thus 27 in total. As yet Seeley did not designate a
type species. Seeley did not accept Owen's position. In 1881 he designated
O. simus the type species of
Ornithocheirus and named a new separate species called
O. bunzeli. In 1888,
Edwin Tulley Newton reassigned several existing species names into
Ornithocheirus, which created new combinations:
O. clavirostris,
O. daviesii,
O. sagittirostris,
O. validus,
O. giganteus,
O. clifti,
O. diomedeus,
O. nobilis,
O. curtus,
O. macrorhinus and
O. hlavaci. He also reassigned the species
O. umbrosus and
O. harpyia into
Ornithocheirus, which were formerly species given to the genus
Pteranodon by
Edward Drinker Cope back in 1872. In 1914
Reginald Walter Hooley made a new attempt to structure the large number of species. Hooley synonymized Owen's
Criorhynchus to
Ornithocheirus, in which he also sunk
Coloborhynchus into that genus, meaning that the only generic name he kept was
Ornithocheirus. To allow for a greater differentiation, Hooley created two new genera, again based on jaw form:
Lonchodectes and
Amblydectes. The genus
Lonchodectes (meaning "lance biter") consisted of the former species
Pterodactylus compressirostris, and
Pterodactylus giganteus, which were reassigned as
Lonchodectes compressirostris, the type species, and
Lonchodectes giganteus, in addition, Hooley also named a new separate species called
L. daviesii. The genus
Amblydectes (meaning "blunt biter") also consisted of three species:
A. platystomus,
A. crassidens and
A. eurygnathus. Hooley's classification however, was rarely applied later in the century, and therefore paleontologists weren't aware of it, and kept subsuming all the poorly preserved and confusing material under the name
Ornithocheirus. In 1964, a Russian-language overview of Pterosauria designated the species
Lonchodectes compressirostris, which was identified as
Pterodactylus compressirostris in the overview, as the type species of
Ornithocheirus, which was then followed by Kuhn in 1967, and Wellnhofer in 1978, yet those authors weren't aware that back in 1881, Seeley made already made the species
P. simus as the type species of
Ornithocheirus, in which defined the new combination of
O. simus. From the seventies onwards many new pterosaur fossils were found in
Brazil in deposits slightly older than the Cambridge Greensand, 110 million years old. Unlike the English material, these new finds included some of the best preserved large pterosaur skeletons and several new genera names were given to them, such as
Anhanguera. This situation caused a renewed interest in the
Ornithocheirus material and the validity of the several names based on it, for it might be possible that it could by more detailed studies be established that the Brazilian pterosaurs were actually
junior synonyms of the European types. Several European researchers concluded that this was indeed the case. Unwin revived
Coloborhynchus and
Michael Fastnacht Criorhynchus, each author ascribing Brazilian species to these genera. However, in 2000 Unwin stated that
Criorhynchus could not be valid. Referring to Seeley's designation of 1881 he considered
Ornithocheirus simus,
holotype CAMSM B.54428, to be the type species. This also made it possible to revive
Lonchodectes, using as type the former
O. compressirostris, which then became
L. compressirostris. As a result, though over forty species have been named in the genus
Ornithocheirus over the years, only
O. simus is currently considered valid by all pterosaur researchers. The species
Tropeognathus mesembrinus, which was named by Peter Wellnhofer in 1987, was assigned to
Ornithocheirus by
David Unwin in 2003, making
Tropeognathus a junior synonym. In 1989 however,
Alexander Kellner considered it as an
Anhanguera mesembrinus, then as a
Coloborhynchus mesembrinus by
André Veldmeijer in 1998 and as a
Criorhynchus mesembrinus by Michael Fastnacht in 2001.
Formerly assigned species In 2013, Rodrigues and Kellner found
Ornithocheirus to be monotypic, containing only
O. simus, and placed most other species in other genera, or declared them
nomina dubia. They also considered
O. platyrhinus a junior synonym of
O. simus. Misassigned species: •
O. compressirostris (Hooley, 1914) =
Pterodactylus compressirostris, Owen, 1851 [now classified as
Lonchodectes] •
O. crassidens (Seeley, 1870) = [now classified as
Amblydectes] •
O. cuvieri (Seeley, 1870) =
Pterodactylus cuvieri, Bowerbank, 1851 [now classified as
Cimoliopterus] •
O. curtus (Hooley, 1914) =
Pterodactylus curtus, Owen, 1874 •
O. giganteus (
Owen, 1879) =
Pterodactylus giganteus, Bowerbank, 1846 [now classified as
Lonchodraco] • "O."
hilsensis (Koken, 1883) = indeterminate
Neotheropoda •
O. mesembrinus (
Wellnhofer, 1987) =
Tropeognathus mesembrinus, Wellnfofer, 1987 •
O. nobilis (Owen, 1869) =
Pterodactylus nobilis, Owen 1869 •
O. sagittirostris (Seeley, 1874) = [now classified as
Serradraco] •
O. simus (Owen, 1861) = [originally
Pterodactylus] (
type) •
O. sedgwicki (Owen, 1859) =
Pterodactylus sedgwickii, Owen 1859 [now classified as
Aerodraco] • "O."
wiedenrothi (Wild, 1990) = [now classified as
Targaryendraco]
Cimoliornis diomedeus,
Cretornis hlavatschi, and
Palaeornis clifti, originally misidentified as birds, were once referred to
Ornithocheirus in the past, but recent papers have found them to be distinct;
Cimoliornis may be closer to azhdarchoidea,
Cretornis is a valid genus of azhdarchid, and
Palaeornis was shown to be a lonchodectid in 2009.
O. buenzeli (Bunzel 1871, often misspelled and incorrectly attributed as
O. bunzeli, Seeley 1881), cited in the past as evidence of Late Cretaceous ornithocheirids, has since been re-identified as a likely azhdarchid as well. ==Description==