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Zupaysaurus goes back into The Matrix
I previously added Zupaysaurus into the data matrix of the following paper-
T.R. Holtz, Jr. 2000 [marked as 1998]. A New Phylogeny of the Carnivorous
Dinosaurs. GAIA 15: 5-61
I updated the codings from this analysis after talking to Jaime and Mickey
because I was uncertain about a few things.
Consensus tree from 60 MPTs, 1415 steps, CI 0.3512, HI 0.6488, RI 0.6384
--+--allzero
|--Herrerasauridae
`--+--Prosauropoda
`--+--+--+--Coelophysidae
| | `--Elaphrosaurus
| `--+--Dilophosaurus
| `--Zupaysaurus
`--+--+--Ceratosaurus
| `--+--Abelisaurus
| `--Carnotaurus
`--+--Torvosaurus
`--+--Eustreptospondylus
`--+--Piatnitzkysaurus
`--+--Afrovenator
`--+--Megalosaurus
`--+--+--?Megalosaurus? hesperis
| `--Spinosauridae
`--+--Monolophosaurus
`--+--+--+--Yangchuanosaurus
| | `--Sinraptor
| `--+--+--Allosaurus
| | `--Neovenator
| `--+--Acrocanthosaurus
| `--+--Carcharodontosaurus
| `--Giganotosaurus
`--|-- (see tree below)
--+--Proceratosaurus
|--Gasosaurus
`--+--+--Bagaraatan
| `--Ornitholestes
`--+--Scipionyx
`--+--+--Compsognathidae
| `--+--Tyrannosauridae
| `--+--Troodontidae
| `--+--Pelecanimimus
| `--Ornithomimidae
`--+--Dryptosaurus
`--+--Coelurus
`--+--Protarchaeopteryx
|--Caudipteryx
|--Deltradromeus
`--+--+--Therizinosauroidea
| `--+--Caenagnathidae
| |--Microvenator
| `--Oviraptoridae
`--+--Dromaeosauridae
`--+--Archaeopteryx
|--+--Rahonavis
| `--Unenlagia
`--+--Alvarezsauridae
`--+--Confuciuosornithidae
`--Ornithothoraces
Differences from Holtz (2000)-
Ceratosaurs are closer to tetanurans than coelophysoids.
Elaphrosaurus falls out as a coelophysoid.
Spinosaurids are closer to avetheropods than other non-avetheropodan
tetanurans.
Monolophosaurus is not a carnosaur.
Compsognathids are the sistergroup to other arctometatarsalians.
Bagaraatan and Ornitholestes form a clade.
Dryptosaurus is a maniraptoran.
Coelurus is a maniraptoran.
Archaeopteryx is not closer to Pygostylia than Rahonavis.
Support for clades:
Coelophysoidea-
Subnarial gap (11.1)
Tip of dorsal ramus of quadratojugal contacts tip of lateroventral ramus of
squamosal (64.1)
Axial parapophyses reduced (142.1)
Axial diapophyses absent (143.1)
Axial pleurocoels absent (145.1)
Two pairs of postaxial cervical pleurocoels (148.2)
Dorsal transverse processes strongly backturned caudally and triangular in
dorsal view (170.1)
Two pairs of cranial and median dorsal pleurocoels (180.2)
Supracetabular shelf on ilium (300.1)
Pubic fenestra ventral to obturator foramen (308.1)
Pubic orientation, proximal portion of shaft approximately 30 degrees from
horizontal (309.1)
Ischial antitrochanter large (321.1)
Anterior (= lesser) trochanter is a conical prominence (335.1)
Medial epicondyle (= mediodistal crest) pronounced, extends one quarter or
more the length of the femoral shaft (340.1)
Groove in lateral condyle of femur (342.1)
Sulcus along medial side of base of crista tibiofibularis (345.1)
Anterior surface of distal fibula overlaps ascending process of astragalus
cranially (359.1)
Metatarsal III dorsal surface area clearly larger than metatarsals II and IV
(375.1)
(Elaphrosaurus + Coelophysidae)-
Neck length twice or more the length of the skull (136.1)
Cervical neural spines low and craniocaudally short (154.1)
Midcervical centra length four times or more diameter of cranial face
(160.1)
Cervical ribs fused to centra in adults (165.1)
Five sacrals (185.3)
Synsacrum present in adults (189.1)
Pelvic girdle sutures fused in adults (285.1)
Astragalocalcaneum fused (366.1)
Metatarsal III dorsal surface shape dumbbell shaped (cranial and
(especially) plantar surfaces expanded slightly to overlap surfaces of
metatarsals II and IV) (376.2)
(Zupaysaurus + Dilophosaurus)-
Paired ridges along lateral edges of nasals (26.2)
Orbit shape oval, rounded dorsally, constricted ventrally (45.1)
Squamosal constriction of lateral temporal fenestra (57.1)
Reduced overlap of dentary onto postdentary bones (110.1)
Caudalmost maxillary tooth position rostral to orbit (133.1)
I then added constraint tree trying to force Zupaysaurus to be a tetanuran
using the topology of Arcucci & Coria (2003).
(Prosauropoda(Herrerasauridae(((Dilophosaurus,Coelophysidae)(Carnotaurus,Ceratosaurus))(Zupaysaurus,Sinraptor,Allosaurus,Giganotosaurus,Tyrannosauridae))))
Consensus tree from 100 MPTs, 1415 steps, CI 0.3512, HI 0.6488, RI 0.6384
--+--allzero
|--Herrerasauridae
`--+--Prosauropoda
`--+--+--+--Coelophysidae
| | `--Dilophosaurus
| `--+--Elaphrosaurus
| `--+--Ceratosaurus
| `--+--Abelisaurus
| `--Carnotaurus
`--+--Zupaysaurus
`--+--+--Spinosauridae
| `--?Megalosaurus? hesperis
`--+--Megalosaurus
`--+--Eustreptospondylus
`--+--Torvosaurus
`--+--Piatnitzkysaurus
`--+--Afrovenator
`--+--+--Monolophosaurus
| `--Allosauroidea *
`--+--Proceratosaurus
|--Gasosaurus
`--+--+--Bagaraatan
| `--Ornitholestes
`--+--Scipionyx
|--Dryptosaurus
|--Compsognathidae
|--Arctometatarsalia *
`--Maniraptora *
Clade * = Internal topology did not appear differently from the tree
presented above, so repeating it would be redundant
This tree is as parsimonious as the tree presented without constraints, and
is closer to Holtz (2000) in several respects (i.e. Elaphrosaurus is a
neoceratosaur, monophyletic Ceratosauria, Monolophosaurus is a carnosaur,
compsognathids are not arctometatarsalians, & Dryptosaurus is not a
maniraptoran). Now let?s look at the support for this tree.
Tetanurae-
Slot in ventral process of lacrimal for jugal (34.1)
Broad contact between the dorsal ramus of quadratojugal and the
lateroventral ramus of squamosal (64.2)
Caudalmost maxillary tooth position rostral to orbit (133.1)
Note that character 64 is unknown in most basal tetanurans, except for
Torvosaurus in which the state is present. Character 133 is also developed
in Dilophosaurus.
In order to further test for possible positions of Zupaysaurus within the
Theropoda, I decided to run it in the data matrix from Rauhut (thesis,
2000). Mickey was kind enough to send me codings for Cryolophosaurus and
?Dilophosaurus? sinensis.
Consensus tree from 100 MPTs, 674 steps, CI 0.4065, HI 0.5935, RI 0.7406
--+--Euparkeria
|--Marasuchus
`--+--Ornithischia
`--+--Sauropodomorpha
`--+--Eoraptor
`--+--+--Herrerasaurus
| `--Staurikosaurus
`--+--+--Gojirasaurus
| |--Segisaurus
| |--Coelophysis
| |--Syntarsus
| |--Shuvosaurus
| `--+--Liliensternus airelensis
| `--Liliensternus liliensterni
`--+--+--Dilophosaurus
| `--+--Zupaysaurus
| `--+--?Dilophosaurus? sinensis
| `--Cryolophosaurus
`--+--+--Ceratosaurus
| `--+--Elaphrosaurus
| `--Abelisauridae
`--+--Piatnitzkysaurus
|--?Szechuanosaurus? zigongensis
`--+--+--Poekilopleuron
| |--Magnosaurus
| |--Afrovenator
| |--Monolophosaurus
| |--Sinraptoridae
| |--Neovenator
| |--Carcharodontosauridae
| |--Allosaurus
| `--+--Torvosaurus
| `--+--Chilantaisaurus
| `--Baryonychidae
`--|-- (see tree below)
--+--Proceratosaurus
`--+--+--Coelurus
| `--+--Sinosauropteryx
| `--+--Compsognathus
| `--SMNK 2349Pal
`--+--+--Stokesosaurus
| `--Tyrannosauridae
`--+--Ornitholestes
`--+--+--Deltadromeus
| `--Ornithomimosauria
`--+--Bagaraatan
|--+--Therizinosauroidea
| `--+--Caudipteryx
| `--+--Microvenator
| |--Oviraptorosauria
| `--Avimimus
`--+--+--Unenlagia
| `--Aves
`--+--Troodontidae
`--Dromaeosauridae
It is undeniable that the results are interesting for this matrix. The idea
of Dilophosaurus, Cryolophosaurus, and ?Dilophosaurus? sinensis forming a
clade has been suggested before by HP Waylon Rowley. Now let?s look at the
support.
Averostra-
Promaxillary foramen present (16.1)
Lacrimal fenestra present (31.1)
Lacrimal ?horn? present (32.1)
Prefrontal excluded from the anterior rim of the orbit in lateral view being
displaced posteriorly and/or medially, ventral process absent (34.1)
Quadratojugal process of the squamosal broad, and usually somewhat expanded
(45.1)
Mid-cerebral vein exits through separate foramen antero-dorsal to the
trigeminal foramen (61.1)
Tooth row ends at the anterior rim of the orbit (70.1)
Pleurocoels developed as foramina (90.1)
Epipophyses on axis strongly pronounced (overhanging the postzygapophyses)
(92.2)
Anterior articular facet of anterior cervical vertebrae significantly wider
than high (101.1)
Epipophyses in anterior cervical vertebrae pronounced, strongly overhanging
the postzygapophyses (102.2)
Pubic apron with medial opening distally above the pubic boot (182.1)
Deep groove on medial side of proximal end of fibula but covering less than
2/3 of the width of the fibula (210.1)
Metatarsal V short, without articular surface, transversely flattened and
bowed anteriorly and distally (223.2)
(Dilophosaurus + (Zupaysaurus + (?Dilophosaurus? sinensis +
Cryolophosaurus)))-
Subnarial gap (9.1)
Pronounced lateral rims of the nasals, sometimes bearing lateral cranial
crests (22.1)
Enlarged, fang-like teeth in the anterior part of the dentary (83.1)
(Zupaysaurus + (?Dilophosaurus? sinensis + Cryolophosaurus))-
Anterior margin of maxillary antorbital fossa squared (13.1)
Quadratojugal with broad, short posterior process that wraps around the
lateroventral edge of the quadrate (47.1).
(?Dilophosaurus? sinensis + Cryolophosaurus)-
Anterior end of jugal excluded from internal antorbital fenestra (24.1)
Tooth row completely antorbital, tooth row ends anterior to the vertical
strut of the lacrimal (70.2).
I used a constraint tree as I did for Holtz?s matrix in order to test which
placement was more parsimonious. Certain adjustments had to made, as there
were different taxa in Rauhut?s analysis than Holtz?s.
(Sauropodomorpha(Herrerasaurus(((Dilophosaurus(Coelophysis,Syntarsus))(Ceratosaurus,Abelisauridae))(Zupaysaurus,Sinraptoridae,Allosaurus,Carcharodontosauridae,Tyrannosauridae))))
Consensus from 100 MPTs, 689 steps, CI 0.3977, HI 0.6023, RI 0.7309
--+--Euparkeria
|--Marasuchus
`--+--Ornithischia
`--+--Sauropodomorpha
`--+--+--Herrerasaurus
| `--Staurikosaurus
`--+--Gojirasaurus
|--+--Liliensternus airelensis
| `--Liliensternus liliensterni
|--Segisaurus
|--Coelophysis
|--Syntarsus
|--Shuvosaurus
|--Dilophosaurus
|--+--Ceratosaurus
| `--+--Abelisauridae
| `--Elaphrosaurus
`--+--+--Zupaysaurus
| `--+--Cryolophosaurus
| `--?Dilophosaurus? sinensis
`--+--Proceratosaurus
|--Piatnitzkysaurus
|--?Szechuanosaurus? zigongensis
|--Coelurosauria *
`--+--Poekilopleuron
|--Magnosaurus
|--Afrovenator
|--Monolophosaurus
|--Allosaurus
|--+--Torvosaurus
| `--+--Chilantaisaurus
| `--Baryonychidae
`--+--Sinraptoridae
`--+--Neovenator
`--Carcharodontosauridae
Clade * = Internal topology did not appear differently from the tree
presented above, so repeating it would be redundant
This tree is 15 steps more than the unconstrained tree. Coelophysidae does
not exist, despite being part of the constrained topology that the analysis
was to look for. It is more parsimonious for the previous tree to be
correct within this matrix.
Also interesting is that Arcucci & Coria write that they ran Z. in the
matrices published by Sereno et al. (1994). This is interesting because
that paper did not present a data matrix, nor did it include Deltadromeus
(because it was not published at the time), Carcharodontosauridae, or
Ornitholestes. It is clear that they meant Sereno et al. 1996 as it does
present a data matrix and it does include all three of those taxa.
Any questions? ;-D
Nick Gardner
_________________________________________________________________
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