Re: Regarding Spinosaurus

["Mickey_Mortimer11" <Mickey_Mortimer11@email.msn.com>]

George Olshevsky wrote-

> << No, it's not. Becklespinax is, for the theropod with the three
tall-spined
>  vertebrae. Altispinax is based on a tooth. >>
>
> Forgot to mention that the confusion set in when Huene (1923) >referred<
the
> vertebrae to the tooth taxon Megalosaurus dunkeri and simultaneously
renamed
> the genus Altispinax. He neglected to give Altispinax a type species, but
> this was dutifully supplied by Kuhn in 1939 as Altispinax (formerly
> Megalosaurus) dunkeri. The invalidity of this reassignment was later
pointed
> out by Steel (1970) and maybe others. Since the tall-spined Wealden
vertebrae
> are clearly not Megalosaurus, and they cannot be referred to the tooth
genus
> Altispinax (regrettably named after the vertebrae), they require a new
genus
> and species. Greg Paul supplied the species Acrocanthosaurus altispinax in
> PDW in 1988, and I supplied the genus Becklespinax in MM #2 in 1991.

Rauhut has a different version of the situation, suggesting Altispinax
altispinax is the correct name for the dorsals, while Megalosaurus dunkeri
is the name for the tooth.
As stated in his thesis-
"However, Huene (1926a: pp. 482-483) stated: "There is another specimen from
the Wealden of Battle...consisting of three articulated middle dorsal
vertebrae, with extremely high neural spines. ...if it were certain that
such dorsal vertebrae belong to Megalosaurus dunkeri, it would be necessary
to put it into a distinct genus, for which the name Altispinax, gen. nov.,
might be reserved.", and in 1932 (p. 235): "Three articulated dorsal
vertebrae with very elongated neural spines, figured by Owen (202, Pl. 19),
also seem to belong here; ...In 1926 ..., I based the genus Altispinax on
these specimens." (my translation). From this it is clear firstly that the
generic name Altispinax was proposed for the three vertebrae, and secondly
does not refer to the nomen dubium Megalosaurus dunkeri. Since Huene (1926)
did not propose a new specific name, the first available species name given
exclusively to the vertebrae is Paul's (1988a) Acrocanthosaurus altispinax,
the species thus becomes Altispinax altispinax (Paul, 1988a). Becklespinax
Olshevsky, 1991, is thus an objective junior synonym of Altispinax Huene,
1923."

Mickey Mortimer