by Fred Bervoets
 

The vertebrate fauna of the Hateg Basin (Late Cretaceous : Latest Maastrichtian; Antonescu et al. 1983) was discovered in 1895 and first described in 1900 by Nopcsa. The fauna comes mostly from the fluviatile, continental deposits of the Densus-Ciula and Sinpetru formations, cropping out in the north-western and central parts of the basin respectively (Grigorescu 1992).

The deposits of the Romanian Hateg Basin have yielded numerous remains of herbivorous dinosaurs along with those of turtles and crocodilians. The titanosaur Magyarosaurus (M.dacus, M.hungaricus and M.transsylvanicus), ornithopods as the iguanodontids Bihariosaurus, Rhabdodon priscus and Iguanodon mantelli, the hadrosaurid Telmatosaurus transsylvanicus, the dryosaurid Valdosaurus canaliculatus, the nodosaurid \"Struthiosaurus transsylvanicus NN\" are well known; but those of theropods are scare, represented mostly by hindlimb elements and teeth.

Magyarosaurus

Magyarosaurus (\"Magyar lizard\") was created by Huene,1932 for a large collection of scattered titanosaurid bones from the top of the Cretaceous in Romania, most of them belonging to small individuals. As with so many of the titanosaurid collections from India, Argentina, southern France, and Spain these bones are totally dissociated and may represent more than one genus as shown by the slender and robust types of humeri. Most of the Magyarosaurus bones belong to a slender- limbed type of titanosaurid. Magyarosaurus > M.dacus (Nopcsa,1915) = Titanosaurus dacus (Nopcsa,1915) Magyarosaurus > M.transsylvanicus (Huene,1932) > M.hungaricus (Huene,1932)

Bihariosaurus

Bihariosaurus, (\"Bihor (Romania) lizard\") Marinescu, 1989. From the Bihor County region of the Carpathean Mountains. Rhabdodon priscus, (\"fluted tooth\") Matheron,1869 This planteating dinosaur is closely related to Telmatosaurus. Its the most common dinosaur of Transsylvania. Fossil remains of this iguanodontid are also found in France, Spain and Austria which makes this a typically European dinosaur. Rhabdodon was a selective eater, his wide belly and the position of the pubis indicates its stomach was huge.

Rhabdodon

Rhabadon = Mochlodon (Seeley,1881) Rhabdodon > R.priscus (Matheron,1869) >> Iguanodon suessi (Bunzel,1871) Oligosaurus adelus (Seeley,1881) Ornithomerus gracilis (Seeley,1881) Mochlodon robustus (Nopcsa.1900) Onychosaurus hungaricus (Nopcsa,1902) Camptosaurus inkeyi (Nopcsa,1900) Rhabdodon > R.septimanicus (Buffetaut & Le Loeuff,1991)

Iguanodon

Iguanodon mantelli, Meyer,1832

Iguanodon = Iguanosaurus (Ritgen,1828) Heterosaurus (Cornual,1850) Iguanodon > I.anglicus (Holl,1829) >> Cetiosaurus brevius (Owen,1842) Streptospondylus major (Owen,1842) Iguanodon > I.atherfieldensis (Hooley,1824) > I. mantelli (Meyer,1832) Vectisaurus valdensis (Hulke,1879) Therosaurus mantelli (Fitzinger,1843) Sphenospondylus gracilis (Seeley, 1882) Heterosaurus neocomiensis (Cornuel,1850 partim). Iguanodon > I.bernissartensis (Boulenger,1881) > I.seelyi (Hulke,1822) Iguanodon > I.dawsoni (Lydekker,1888) Iguanodon > I.fittoni (Lydekker,1889) >> I.hollingtoniensis (Lydekker,1889) Iguanodon > I.hoggi (Owen,1874) Iguanodon > I.lakotaensis (Weishampel & Bjork,1989) Iguanodon > Iguanodon orientalis \"\" NN (Rozhdestvensky,1952)

Telmatosaurus

Telmatosaurus transsylvanicus, Nopcsa,1903 (\"swamp lizard\") to replace preoccupied Limnosaurus Nopcsa, 5-10 fragmentary skulls, some with associated postcrania, mixed age classes.

Telmatosaurus = Limnosaurus (Nopcsa,1899) , Hecatasaurus (Brown,1910) Telmatosaurus > T.transsylvanicus (Nopcsa,1900) = Limnosaurus transsylvanicus (Nopcsa,1899)

Valdosaurus

Valdosaurus canaliculatus Galton,1977 (\"Wealden lizard\") Femora, other postcranial elements, dentary, teeth. Remains of Valdosaurus are known from England, Niger and Romania. Valdosaurus > V.canaliculatus (Galton,1975) = Dryosaurus canaliculatus (Galton,1975) Valdosaurus > V.nigeriensis (Galton & Taquet,1982)

Struthiosaurus

\"Struthiosaurus transsylvanicus NN\" Nopcsa,1915 Based on an partial skull and skeleton of about 2 to 3 m total length. The skull fragment has a closed supratemporal fenestra, narrow infratemporal fenestra, and fused paroccipital process and squamosal, all features of nodosaurids. Struthiosaurus (\"ostrich reptile\") is known from the Latest Cretaceous of southern Europe (France, Hungary, Austria) and especially from localities in an area originally known as Transylvanya in Romania.

Struthiosaurus = Pleuropeltus (Seeley, 1881) Struthiosaurus > S.austriacus (Bunzel, 1870) > S.transilvanicus NN (Nopcsa, 1915)) >> Crataeomus lepidophorus (Seeley,1881) >> Danubiosau rusanceps (Bunzel,1871 partim) >> Crataeomus pawlowitschii (Seeley,1881 partim)

New material allows the recognition of an unexpected diversity of predators in the Hateg fauna.

Teeth of various morphologies are reported to represent several distinct taxa of small theropods: a velociraptorine dromaeosaurid, a \"troodontid-like\"small theropod, cf. Euronychodon and perhaps a fourth, peculiar small theropod with sharp, but unserrated carinae on the teeth.

Re-examination of previously published theropod material also suggests such diversity. a fragmentary femur, previously referred to Elopteryx, probably belong to a derived maniraptorian.

Elopteryx

Elopteryx (\"Marsh wing\") was originally identified as an advanced Cretaceous bird based on the shape of the femur. And is now by some researchers considered as a troodontid dinosaur but it also possible that its a bird.

In Le Loeuff, J., E. Buffetaut, P. Mechin & A. Mechin-Salessy. 1992. The first record of dromaeosaurid dinosaurs (Saurischia, Theropoda) in the Maastrichtian of southern Europe: paleobiogeographical implications. Bulletin de la Societe geologique de France 163: 337-343.

The authors demonstrate that the Elopteryx is a legitimate dromaeosaurid, whereas some of the other coelurosaurian forms are less certain.

A distal end of a femur seems to document a small ceratosaur, while the tibiotarsi (holotypes of Bradycneme and Heptasteornis) may represent a non-maniraptorian tetanuran theropod. Whiteout diagnostic remains of small theropods, it is inappropriate to give the reported material generic names; consequently informal use of the published names \"Elopteryx\" and \"Bradycneme\" is recommended. Moreover, for most part of the isolated theropods remains from Hateg there are no reasons to group them under the same name; one such case may be represented however, by some skull elements and the velociraptorine teeth.

The diversity of the small theropods in the Hateg fauna, together with the possible absence of a large \"top\" theropod, (the only know possible larger theropod is the nomen nudem Megalosaurus hungaricus represented by a single tooth from the Sinpetru Beds) represents the first such case reported for the Late Cretaceous faunas.

This phenomenon is probably linked to the restricted, insular habitat of the Hateg fauna, which could not accommodate and support any larger sized predator.

Theropod dinosaurs from the Hateg Beds

Aristosuchus Seeley, 1887 [theropoda Nomina Dubia] \"superior crocodile\" named for a kind of reptile Seeley originally considered distinct from both dinosaurs and crocodiles, though with some features of both; based on a specimen named Calamospondylus by Fox in 1866, a name now generally considered a nomen nudum. Found in the Bauxite of Cornet, Judethaen Bihor but also known form the Isle of Wight, England. {Berriasian Valanginian Hauteravian}

Bradycneme draculae Harrison & Walker,1975 vide Le Leouff et al, 1992 (\"heavy leg\") originally identified as a giant owl is represented by a large sized distal tibiotarsus.

Le Leouff et al. 1992 showed that it is a junior synonym of Elopteryx nopcsai. However Bradycneme shows at least one clear synapomorphy (cranial transverse groove on astragalar condylus) that seems to exclude it from the maniraptorian (even coelurosaurian) tetanurae, a clade where \"Elopteryx\" was shown to probably belong.

B. draculae can be considered as a unique small theropod taxon from Hateg that shares most characters with troodontids, but also has a synapomorphy that seems to exclude it from the derived coelurosaurs.

Thus the systematic position of \" B. draculae\" cannot be more precisely ascended at present and its probably preferable to use the name only informally.

Elopteryx nopscsai Andrews,1913 vide Le Loeuff, Buffetaut, Mechin & Mechin-Salessy, 1992 (\"marsh wing\") originally identified as an advanced Cretaceous bird based on the shape of the fragmentary femur.

Some scientist believe that these extinct forms approach most nearly to the Steganopodes, e.g., the cormorant... others consider it a troodontid dinosaur. However in Le Loeuff, J., E. Buffetaut, P. Mechin & A. Mechin-Salessy, 1992. \"The first record of dromaeosaurid dinosaurs (Saurischia, Theropoda) in the Maastrichtian of southern Europe: paleobiogeographical implications. Bulletin de la Societe geologique de France 163: 337-343\", the authors demonstrate that the Elopteryx is a legitimate dromaeosaurid.

Zoltan Csiki and Dan Grigorascu in \"Small theropods from the Late Cretaceous of the Hateg Basin (Western Romania) -un unexpected diversity at the top of the food chain. Oryctos Vol. 1 87-104\" notice that \"Elopteryx nopcsai\" is restricted to the proximal femora of a derived maniraptorian, close to either dromaeosaurids, troodontids (or even Avimimus), or representing a new taxon whitin this clade (\"eloperygines\" of Le Loeuff et al., 1992).

Whiteout better associated material its impossible to recognize whether such disarticulated like that of the Hateg Basin belongs to the same taxon; moreover as their currently recognized synapomorphies show, the hindlimb elements seem to represent taxa from different theropod clades.

The only case of recognizable conspecificity may be represented by the velociraptorine teeth and the skull roof fragments described by Weishampel and Jianu (1996); but it must be pointed out that even if \"Elopteryx\" should prove to represent a dromaeosaurid, it seems to exhibit such primitive characters that exclude its conspecificity with the theropod of Weishampel and Jianu. Thus the name \"Elopteryx\" should not be used for this later taxon.

Heptasteornis andrewsi Harrison & Walker,1975 (\"seven-towns bird\"). [Troodontidea Nomen nudem] Possible junior synonym for \"Bradycneme draculae\" . Originally identified as a large owl.

Megalosaurus hungaricus Nopcsa,1901 [?Carnosauria Nomen nudem] Tooth

The Hateg fauna seems to have had a different more \"diffuse\"top of the food pyramid, with a larger number of small theropods replacing the top predator. This phenomenon seems to be related to the general body dwarfism, already noted for other Hateg dinosaurs (Weishampel et al., 1991) which in turn is certainly related to the insular, small-area habitat of this fauna.

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