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New dinosaur taxa, with a Latin flavor (Spanish & Argentine)



I can't find this critter on the DML Archives, so I think this may be the
first posting mentioning it:

Just recieved in the mail the following paper:
Sanz, J. L., J. E. Powell, J. Le Loueff, R. Martinez & X. Pereda-Suberbiola.
1999.  Sauropod remains from the Upper Cretaceous of Lan~o (Northcentral
Spain). Titanosaur phylogenetic relationships.  Est. Mus. Cienc. Nat. de
Alava 14 (Num. Espec. 1): 235-255.

Describes the new titanosaur _Lirainosaurus astibiae_ ([Dr. Humberto]
Astiba's slender lizard; "lirain" is Basque for slender) from the Lan~o
outcrop of the upper Campanian (or possibly early Maastrichtian) of Spain.
Type is an anterior caudal vert; paratypes include an occipital part of the
skull, isolated teeth, dorsals, caudals, scapula, coracoid, sternal plate,
humeri, fragments of ilium and pubis, femora, tibia, dermal scutes.

The text mentions a well preserved _Epachtosaurus_ from the Ocho Hermanos
locality of Chubut, Argentina, that seems to lack osteoderms.

Their analysis does not address where titanosaurs fit in sauropod phylogeny;
instead it looks at the ingroup relationship.  Unfortunately, their outgroup
is _Patagosaurus_: would have been a LOT nicer if they used _Brachiosaurus_
as an outgroup, as most recent studies indicate a sister group relationship
of a clade containing _Brachiosaurus_ to the classic titanosaurs.

Their results (with their taxonomy):
_Patago._
unnamed
  unnamed
    _Haplocanthosaurus_
    _Andesaurus_
  Titanosauroidea
    _Opisthocoelicaudia_
    Titanosauria
      _Epachthosaurus_
      Eutitanosauria taxon nov.
        unnamed
          _Saltasaurus_
          _Argyrosaurus_
        unnamed
          _Lirainasaurus_ [sic]
          Peiropolis titanosaur

(The last is an as-yet unnamed titanosaur from Peiropolis, Brazil (briefly
described previously by Powell in 1987).

They "define" Titanosauria (a bit late, as it has already been done by
Sereno: all taxa closer to _Saltasaurus_ than to _Euhelopus_...) as all
descendants of the most recent common ancestor of _Epachthosaurus_,
_Salta._, _Argyro._, _Liraino._, and the Peiropolis titanosaur.

Eutitanosauria is defined ass all descendants of the MRCA of _Salta._,
_Argyro._, _Liraino._, and the Peiropolis titanosaur.

Also just in, _Notohypsilophodon comodorensis_ is finally a legit taxon:

Martinez, R.  1998. _Notohypsilophodon comodorensis_ gen. et sp. nov. Un
Hypsilophodontidae (Ornitischia [sic]: Ornithopoda) del Cretacico Superior
de Chubut, Patagonia Central, Argentina.  Acta Geologica Leopoldensia 21:
119-135.

>From the Bajo Barreal Fm. of the ?Cenomanian of southern Chubut, Argentina.
Known only from the holotype (a juvenile): cervicals, dorsals, sacrals, and
caudals; rib fragments; partial scapula; coracoid; humerus; ulnae; partial
femur; tibiae; fibulae; astragalus & calcaneum; and 13 pedal phalanges
(including 3 unguals).

Unfortunately (or, as it comes out more dramatically in Spanish,
"lamentablemente"!) the remains do NOT contain the skull, wherein are many
of the best features for determining relationships in Ornithopoda.  Its
reference to Hypsilophodontidae is based on: presence of an ischadic groove
(yet another good band name... :-); anterior trochanter well below greater
trochanter; shallow intertrochanteric cleft and absence of extensor groove
in the distal end; cadual flexure of the humerus at level of the
deltapectoral region.  Also, it seems to lack iguanodontian features (the
traditional diagnosis for hypsilophodonts... :-S ).

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796