Lonchodectes

Taxobox
name = "Lonchodectes"
fossil_range = Early Cretaceous-early Late Cretaceous
regnum = Animalia
phylum = Chordata
classis = Sauropsida
ordo = Pterosauria
subordo = Pterodactyloidea
superfamilia = ?Azhdarchoidea
familia = Lonchodectidae
genus = "Lonchodectes"
genus_authority = Hooley, 1914
subdivision_ranks = Species
subdivision = See text.

"Lonchodectes" (meaning "lance biter") was a genus of ?azhdarchoid pterosaur from several formations dating from the ?Valanginian to the Turonian (Lower Cretaceous-Upper Cretaceous) of England, mostly in the area around Kent. The species belonging to it had been assigned to "Ornithocheirus" until David Unwin's work of the 1990s and 2000s, and the genus is not universally accepted as distinct.Kellner, A.W.A. (2003). Pterosaur phylogeny and comments on the evolutionary history of the group: In: Buffetaut, E., and Mazin, J.-M. (Eds.). "Evolution and Palaeobiology of Pterosaurs". Geological Society Special Publication 217:105-137. 1-86239-143-2.] Several potential species are known; most are based on scrappy remains, and have gone through several other generic assignments. The genus is part of the complex taxonomy issues surrounding Early Cretaceous pterosaurs from Brazil and England, such as "Amblydectes", "Anhanguera", "Coloborhynchus", and "Ornithocheirus" (and its possible synonyms "Criorhynchus" and "Tropeognathus").

History and species

Numerous species have been referred to this genus over time, and only those more widely connected with the genus are included here.

The type species, "L. compressirostris", is based on BMNH 39410, a partial upper jaw from the Turonian-age Upper Cretaceous Upper Chalk near Kent. Richard Owen named in 1851 as a species of "Pterodactylus";Owen, R. (1851). Monograph on the fossil Reptilia of the Cretaceous Formations. "The Palaeontographical Society" 5(11):1-118.] it was transferred to "Ornithocheirus" in 1870 by Harry Govier Seeley,Seeley, H.G. (1870). "The Ornithosauria: an Elementary Study of the Bones of Pterodactyles". Cambridge, 130 pp.] before becoming the type species of "Lonchodectes" in Hooley's 1914 review of "Ornithocheirus".Hooley, R.W. (1914). On the Ornithosaurian genus "Ornithocheirus" with a review of the specimens from the Cambridge Greensand in the Sedgwick Museum, Cambridge. "Annals and Magazine of Natural History", series 8, 78:529-557.] Confusingly, this species was also long regarded, incorrectly, as the type species of "Ornithocheirus".cite journal |last=Unwin |first=David M. |authorlink=David M. Unwin |year=2001 |title=An overview of the pterosaur assemblage from the Cambridge Greensand (Cretaceous) of Eastern England |pages=189–222 |journal=Mitteilungen as dem Museum für Naturkunde, Berlin, Geowissenschaftlichen Reihe |volume=4] Hooley added two other species at this time, both of which had also been originally referred to "Pterodactylus", then to "Ornithocheirus": "L. giganteus", a Cenomanian-age jaw fragment;Bowerbank, J.S. (1846). On a New Species of Pterodactyl. Found in the Upper Chalk of Kent (P. giganteus). "Quarterly Journal of the Geological Society" 2:7–9.] and "L. daviesii", another jaw fragment, from an Albian-age formation.Owen, R. (1874). "A Monograph on the Fossil Reptilia of the Mesozoic Formations. 1. Pterosauria." "The Palaeontographical Society Monograph" 27:1–14.]

The genus acquired several more former "Pterodactylus" and "Ornithocheirus" species in the 1990s-2000s. "L. sagittirostris", based on BMNH R1823, a lower jaw fragment from the ?Valanginian-Hauterivian-age Lower Cretaceous Hastings Beds of East Sussex, and "L. platystomus" had been acquired by 2000.Unwin, D.M., Lü, J., and Bakhurina, N.N. (2000). On the systematic and stratigraphic significance of pterosaurs from the Lower Cretaceous Yixian Formation (Jehol Group) of Liaoning, China. "Mitteilungen Museum für Naturkunde der Humboldt-Universität zu Berlin, Geowissenschaftliche Reihe" 3:181–206.] Two additional species based on jaw fragments, both from the Albian-age Cambridge Greensand, were added by 2003: "L. machaerorhynchus" and "L. microdon",cite book |last=Unwin |first=David M. |authorlink=David M. Unwin |year=2003 |title=Evolution and Palaeobiology of Pterosaurs |editor=Buffetaut, Eric; and Mazin, Jean-Michel, (eds.) |chapter=On the phylogeny and evolutionary history of pterosaurs |pages= 139-190 |publisher=Geological Society |location=London |series=Geological Society Special Publication 217 |isbn=1-86239-143-2] joining "L. compressirostris", "L. giganteus", "L. platystomus", and "L. sagittirostris" in his listing of valid species (thus, additional dubious species may also be referred here).Unwin, D.M. (2006). "The Pterosaurs: From Deep Time." Pi Press:New York, p. 273. ISBN 0-13-146308-X.]

Classification

The genus is poorly known and not universally accepted, as noted above. In Peter Wellnhofer's 1991 "The Illustrated Encyclopedia of Pterosaurs" the other major recent synopsis of pterosaurs, written before Unwin's work, the species are included with "Ornithocheirus" (because of "L. compressirostris" being thought to be the type species), and are in fact the main fossils illustrated to represent the genus.cite book |last=Wellnhofer |first=Peter |authorlink=Peter Wellnhofer |title=The Illustrated Encyclopedia of Pterosaurs |origyear=1991 |year=1996 |publisher=Barnes and Noble Books |location=New York |isbn=0-7607-0154-7 |pages=110-113 ] Unwin has them in their own family, Lonchodectidae, which he grouped with the ctenochasmatoids in 2003, and with the azhdarchoids, including the tapejarids and azhdarchids, in 2006.Unwin, D.M. (2006). "The Pterosaurs: From Deep Time." Pi Press:New York, p. 273. ISBN 0-13-146308-X.]

Paleobiology

Unwin considers "Lonchodectes" to have been a generalist, like a seagull, with its conservative jaws and teeth (like those of the much older "Pterodactylus") and small to medium size; he estimates its maximum wingspan at about 2 m (6.6 ft). "Lonchodectes" had long jaws with many short teeth, and the jaws were compressed vertically, like "a pair of sugar tongs with teeth".Unwin, D.M. (2006). "The Pterosaurs: From Deep Time." Pi Press:New York, p. 251. ISBN 0-13-146308-X.] At least some of these species had crests on their lower jaws.Unwin, D.M. (2006). "The Pterosaurs: From Deep Time." Pi Press:New York, p. 106. ISBN 0-13-146308-X.]

References

External links

* [http://www.pterosaur.co.uk/species/UCP/UCP.htm Upper Cretaceous species of "Lonchodectes" (scroll down)] , The Pterosaur Database. Accessed 2007-02-10
* [http://www.pterosaur.co.uk/species/LCP/LCP.htm Upper Cretaceous species of "Lonchodectes" (scroll down)] , The Pterosaur Database. Accessed 2007-02-10
* [http://dml.cmnh.org/2001Nov/msg00559.html Re: Pterosaur Help] , a posting from George Olshevsky on the Dinosaur Mailing List, which, although incomplete, should give some idea as to the complexity of the taxonomy here. Additional, even more dubious species are included. Accessed 2007-02-10