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Re: Aliwalia



In a message dated 97-11-16 01:48:06 EST, forelf@internet19.fr writes:

<< I read in _The Dinosauria_ that a large theropod maxilla was mistakenly
 refered to _Euskelosaurus browni_ by Seeley in 1894. Can this maxilla be
 _Aliwalia_? If it is, does it allow to classify _Aliwalia_ with more
 precision? If so, is it really a herrerasaurid or anything else? >>

Indeed, this maxilla was referred to _Aliwalia_ by Galton, and it seems to
belong to a giant herrerasaurid or ceratosaurian. Here is an unedited excerpt
from my Dinosaur Folios entry for this genus:

        The story of how Aliwalia rex was discovered and described makes an
intricate odyssey. Sometime probably in early 1866, Alfred Brown, an amateur
19th-century fossil collector of some repute from Aliwal North, South Africa,
came across a deposit of bones of what he thought was a large, hitherto
undescribed dinosaur, along a creek named Barnard's Spruit in the Stormberg
Mountains about 15 miles south of his home town. Unearthing the bones proved
difficult, but every so often Brown shipped an assortment from this site to
England and other countries for description.
        The first shipment arrived in the summer of 1866 at the London office 
of Sir
Roderick Impey Murchison, an eminent geologist who, not really knowing what
to do with the specimens, turned them over to Thomas Henry Huxley. Huxley
named Brown's dinosaur Euskelosaurus browni, and it is to this large
prosauropod that most of the other bones in Brown's later shipments were
referred. But even in 1866, Huxley suspected that more than one dinosaur was
represented by the bones in Brown's shipment. Huxley made a fragmentary femur
(later determined to be a tibia) the type specimen of a second dinosaur,
Orosaurus (later called Orinosaurus capensis, still later Euskelosaurus
capensis). But most paleontologists now consider this specimen to have
belonged to another, very large, Euskelosaurus browni individual, if not to
the type animal itself.
        The second shipment was also sent to Murchison, but for some reason it 
was
lost track of. Not until 1980 did Zimbabwean paleontologist Michael R. Cooper
suggest that it might have wound up at the Hofmuseum in Vienna, Austria.
Indeed, an assemblage of Karoo bones in that museum are listed as having been
donated in 1873 (or before) by Alfred Brown through a Consul Adler of Port
Elizabeth, South Africa. Perhaps Murchison returned the material to Brown,
who then had the bones sent along to Vienna. In any case, unhappy with the
treatment his specimens were accorded in England, Brown shipped the third
batch to the Musée d'Histoire Naturelle at the Jardin des Plantes in Paris.
There the bones were examined, placed on exhibit, and described, as
Euskelosaurus specimens, by French zoologist Paul Fischer in 1870. Much
later, in September 1889, Brown personally handed over the fourth and final
collection of Aliwal North bones to the visiting Harry Govier Seeley, who
noted in 1894 that "other portions of the animal were still in the rock."
Those portions, however, were apparently never collected.
        Studies of the Aliwal material carried out in the 1980s indicate that 
most
of the bones, now spread through three museums in three countries (in London,
Vienna, and Paris), very likely belonged to a single skeleton that was once
partially articulated: the type specimen of Euskelosaurus browni. Another
Euskelosaurus browni individual was also present in the material, because a
few of the bones were duplicated. But two bone fragments proved to be
distinctly different from those of Euskelosaurus. They were among the Vienna
specimens, and they had briefly been described and figured in 1906 by
Friedrich von Huene, who even then suspected that they might have belonged to
a dinosaur different from Euskelosaurus.
        The Vienna bone fragments were reexamined by Peter M. Galton as part of 
a
lengthy ongoing study of all known prosauropod material. He was able to show
that the fragments were in all likelihood the top and bottom pieces of the
same bone—a left thigh bone about a yard long of a hitherto unknown large
carnivorous dinosaur related to the much smaller and somewhat earlier South
American predators Herrerasaurus and Staurikosaurus. Furthermore, among the
material that Seeley had been given by Brown in 1889 was a sizable jawbone
armed with large, flat, serrated teeth—quite unlike the teeth of any
prosauropods. Galton strongly suggested, though he could not prove, that the
jawbone belonged to the same dinosaur as the thigh bone. This dinosaur, which
would have been the size of an adult Allosaurus, he named Aliwalia rex.
        Aliwalia rex is the largest known predatory dinosaur from the Late 
Triassic,
so it is incredibly unfortunate that all we have of it are two fragments of a
femur and a single jawbone (which could just possibly have belonged to a
large carnivorous thecodontian rather than to a dinosaur). Good skeletons of
herrerasaurian dinosaurs are very scarce, although teeth and other isolated
bones, such as those identified as Aliwalia rex and others from Europe, seem
to indicate that herrerasaurians had a worldwide distribution during the Late
Triassic epoch.

Technical information
Discoverer: Alfred Brown
When discovered: Before May 24, 1866
Where discovered: Almost certainly the Lower Elliot Formation at Barnard's
Spruit (also called Ezelsklip), Ward, about 15 miles south of Aliwal North,
Albert (Burgersdorp) District, Cape Province, South Africa; this is the same
locality as for the lectotype and paratype specimens of Euskelosaurus browni
Describer: Peter Malcolm Galton
Year described: 1985
Type specimen: The proximal end (NMW 1886-XV-39) and distal end
(NMW-1876-VII-B124) of what is evidently the same large left femur (estimated
to have been 90-100 cm long when complete), both presently kept as separate
specimens at the Naturhistorisches Museum in Vienna, Austria
Other important specimens: (1) a large upper jaw (partial left maxilla,
showing 12 tooth positions, and premaxilla over 40 cm long) with visible
replacement teeth (BMNH R3301), found by Alfred Brown in the Lower Elliot
Formation at the same site as the type Aliwalia rex femur fragments and
perhaps even belonging to the same animal; originally described by Harry
Govier Seeley in 1894 as the jaw of Euskelosaurus browni, it is now kept at
the Museum of Natural History, London, England (it is primarily this specimen
that for many decades—as late as the 1970s—conveyed the impression that
Euskelosaurus was a carnivorous dinosaur, one of the errors in our
understanding of prosauropods at long last corrected by the work of Peter
Galton, Michael Cooper, Jacques van Heerden, and other paleontologists); and
(2) the proximal end of a large left femur (SMNS 51958) found in the Middle
Stubensandstein of Pfaffenhofen, Stromberghöhe, Germany, once thought to have
belonged to Teratosaurus minor but shown by Peter Galton in 1985 to be
similar enough to the type specimens of Aliwalia rex to be provisionally
included in the same family, kept at the Staatliches Museum für Naturkunde,
Stuttgart, Germany; not presently considered to be an Aliwalia specimen but
apparently belonging to a related, unnamed genus of large herrerasaurian