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A New Archosaur (Diapsida, Archosauriformes) from the Marine Triassic of

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DOI: 10.1080/02724634.2012.694383

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 A New Archosaur (Diapsida, Archosauriformes) from the Marine Triassic of
China
Author(s): Chun Li, Xiao-Chun Wu, Li-Jun Zhao, Tamaki Sato, and Li-Ting Wang
Source: Journal of Vertebrate Paleontology, 32(5):1064-1081. 2012.
Published By: The Society of Vertebrate Paleontology
URL: http://www.bioone.org/doi/full/10.1080/02724634.2012.694383

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Journal of Vertebrate Paleontology 32(5):1064–1081, September 2012
© 2012 by the Society of Vertebrate Paleontology

ARTICLE

A NEW ARCHOSAUR (DIAPSIDA, ARCHOSAURIFORMES) FROM THE MARINE TRIASSIC

OF CHINA

CHUN LI,*,1 XIAO-CHUN WU,*,2 LI-JUN ZHAO,3 TAMAKI SATO,4 and LI-TING WANG5
1
Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology,
Chinese Academy of Sciences, P.O. Box 643, Beijing 100044, P. R. China, lichun@ivpp.ac.cn;
2
Canadian Museum of Nature, P.O. Box 3443, Station “D”, Ottawa, ON K1P 6P4, Canada, xcwu@mus-nature.ca;
3
Zhejiang Museum of Natural History, 6 Westlake Culture Square, Hangzhou, Zhejiang Province 310014, China, zhaolj@zmnh.com;
4
Tokyo Gakugei University, 4-1-1 Nukui-Kita-Machi, Koganei City, Tokyo 184-8501, Japan, tsato@u-gakugei.ac.jp;
5
Geological Survey of Guizhou Province, Guiyang 550005, China, wangliting1943@yahoo.com.cn

ABSTRACT—A new Middle Triassic archosaur, Diandongosuchus fuyuanensis, gen. et sp. nov., is described on the basis of
a skeleton from the Zhuganpo Member (Ladinian) of the Falang Formation, eastern Yunnan Province, China. It is primarily
characterized by the nasal process of the premaxilla extending posteriorly well beyond the external naris, the super-sized cora-
coid foramen laterally bordered by the scapula, the ischium with a strongly expanded medial portion anteroposteriorly longer
than the proximodistal height of the bone, and anteriorly notched cervical osteoderms. D. fuyuanensis is a pseudosuchian
on the basis of the crocodile-normal tarsal joint and other features, such as the distal end of the ulna in posterolateral view
squared off, osteoderms with a distinct anterior process, the presacral vertebrae dorsally covered by more than one osteoderm,
dorsal osteoderm alignment dorsal to presacrals 10–24 staggered, the pubis-ischium contact reduced to a thin proximal con-
tact, and the medial contact of the ischia extensive but the dorsal margins separate. It is from a marine deposit but shows few
morphological adaptations of the postcranial skeleton for a semiaquatic way of life when compared with Qianosuchus from
the Anisian limestone of the same area. A phylogenetic analysis derived from an existing data matrix suggests that the new
archosaur occupies the basal-most position in Poposauroidea and further confirms the poposauroid status of Qianosuchus.
On the basis of current information, the discovery of Diandongosuchus does not firmly underscore the affinity of the semiter-
restrial vertebrate faunas between the eastern and western regions along the northern coastline of the Tethys.

INTRODUCTION Qianosuchus, the proterochampsid Chanaresuchus from the Mid-

dle Triassic of Argentina (Romer, 1971), and the semiaquatic
The Archosauria (sensu Gauthier, 1986), the crown group of
spinosaurid dinosaurs (Sereno et al., 1998; Amiot et al., 2010),
the traditional ‘archosaur’ clade (Benton, 1990, 2004), originated
and its skull roof bones are ornamented by pits, grooves, and
in the Early to Middle Triassic and consists of dinosaurs, in-
ridges.
cluding birds, pterosaurs, and crocodylomorphs (Gauthier et al.,
Here, we describe the osteology of the new archosaur and an-
1988; Gower and Wilkinson, 1996). Its early members were long
alyze its phylogenetic relationships within the Archosauria. As
considered to live in terrestrial ecosystems (Charig and Sues,
revealed by the following phylogenetic analysis, a set of skele-
1976; Chatterjee, 1978; Parrish, 1993; Juul, 1994; Wu and Russell,
tal features and the crocodile-normal pattern of the tarsals sug-
2001) until the discovery of Qianosuchus from the Middle Tri-
gest that the new archosaur can be attributed to the Pseudosuchia
assic (Anisian) marine Guanling Formation of Guizhou, China,
(sensu Nesbitt, 2011) and, therefore, the anatomical comparisons
which is semiaquatic and clearly demonstrates adaptation to a
in the following text will be made mainly with pseudosuchian ar-
marine ecosystem (Li et al., 2006).
chosaurs.
Recently, another archosaur specimen was collected from the
Institutional Abbreviations——IVPP, Institute of Vertebrate
Middle Triassic Zhuganpo Member of the Falang Formation in
Paleontology and Paleoanthropology, Chinese Academy of Sci-
Fuyuan County, eastern Yunnan Province, China, less than 50 km
ences, Beijing, China; MCZ, Museum of Comparative Zool-
southwest of the Qianosuchus locality. The Falang Formation
ogy, Harvard University, Cambridge, Massachusetts, U.S.A.;
is thought to represent a sequence of sediments deposited in a
UFRGS, Institute of Geosciences, Federal University of Rio
shelf sea during the Ladinian on the basis of its lithology and in-
Grande de sul, Porte Alegre, Brazil; ZMNH, Zhejiang Museum
vertebrate fossils (Guizhou Bureau of Geology and Mineralogy,
of Natural History, Hangzhou, China.
1997). In addition to the diverse fish fauna and the terrestrial pro-
Anatomical Abbreviations——ac, acetabulum; aic, atlas inter-
torosaur Macrocnemus (Li et al., 2007), various marine reptiles
centrum; amp, medial process of articular; an, angular; aof, an-
such as nothosaurs, placodonts, pachypleurosaur-like animals,
torbital fossa; apcr, anterior process of cervical ribs; ar, articular;
pistosaurs, some protorosaurs, and thalattosaurs are known from
as, astragalus; atna, atlas neural arch; atr, atlas rib; ax, axis; axc,
the Zhuganpo Member (Li et al., 2002; Cheng et al., 2004, 2006;
axial centrum; axna, axial neural arch; axnp, axial neural spine;
Li, 2007; Rieppel et al., 2006, 2010; Zhao et al., 2008a, 2008b,
axr, axial rib; bra, braincase; ca, calcaneum; cal, carpal; caos, cau-
2008c; Sato et al., 2010). The new archosaur had few postcra-
dal osteoderm; cav1, cav5, caudal vertebrae 1, 5; cgs, central seg-
nial anatomical modifications for an aquatic way of life, although
ment of gastralia; chr, chevron; cl, clavicle; co, coracoid; cof, cora-
its large external naris is relatively posteriorly positioned as in
coid foramen; cos, cervical osteoderm; cr, cervical rib; cr4, cr7,
cr8, cervical ribs 4, 7, 8; cv5, cv8, cervical vertebrae 5, 8; d, den-
*Corresponding author. tary; dip, diapophysis; dlp, deltopectoral process; dt3, dt4, distal

1064
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1065

tarsals 3, 4; dv3, dorsal vertebra 3; ec, ectopterygoid; en, exter- with Qianosuchus); and maxilla excluded from external naris
nal naris; eo, exoccipital; f, frontal; fi, fibula; fil, facet for ilium; (shared with Poposaurus).
fis, facet for ischium; fpu, facet for pubis; fqi, facet for quadra-
tojugal; fsc, facet for scapula; fsr1+2, facets for sacral ribs 1+2; DESCRIPTION
fsy, symphysial facet of dentary; gl, glenoid; h, humerus; hy, hy-
oid; icl, interclavicle; il, ilium; is, ischium; j, jugal; l, lacrimal; lf, The skeleton is articulated from the skull to the eighth caudal
left femur; los, limb osteoderm; m, maxilla; mfis, medial facet for vertebra or to the 21st pair of caudal osteoderms. It is embedded
ischium; n, nasal; ob, orbit; od, odontoid process; os, osteoderm; in a slab of clay-limestone and much of the right lateral side of
p, parietal; par, prearticular; pat, proatlas; pbp, parabasisphenoid the skeleton is available for examination, except for the trunk,
process; pf, prefrontal; pl, palatine; pm, premaxilla; po, postor- which is exposed in ventrolateral view, showing the gastralia and
bital; pof, postfrontal; pop, paroccipital process; ptbs, pit for M. stomach content (Fig. 1). The skull was taken out of the slab and
triceps brachii; prq, pterygoid ramus of quadrate; pt, pterygoid; prepared on both sides. The preserved length of the specimen is
pu, pubis; q, quadrate; qh, quadrate head; qj, quadratojugal; qrp, about 97 cm and the length of the body (from the last sacral ver-
quadrate ramus of pterygoid; ran, right angular; ra, radius; rap, tebra to the snout tip of the skull) is about 77 cm. The specimen
retroarticular process; rf, right femur; ro, roller; sa, surangular; may have reached a total length of 155 cm in life if the tail length
sc, scapula; so, supraoccipital; sp, splenial; sq, squamosal; sr1, sr2, occupies 53% to 54% of the total length as in the extant Alligator
sacral ribs 1 and 2; stc, stomach content; stf, supratemporal fenes- sinensis (Cong et al., 1998).
tra; sv1, sacral vertebra 1; ti, tibia; trf, transverse flange; trp, trans-
verse process; vg, ventral groove; ul, ulna; I to V, metacarpals or
Skull and Mandible
metatarsals I to V.
The skull is severely flattened towards the right side and practi-
cally two-dimensional (Figs. 2, 3). The left side is better preserved
SYSTEMATIC PALEONTOLOGY than the right. It is about 24 cm long from the tip of the snout
to the quadrate condyle on the right side. The snout, the portion
DIAPSIDA Osborn, 1903 anterior to the orbit, is about 2.5 times longer than the rest of
ARCHOSAUROMORPHA Huene, 1946 sensu Benton, 1985 the skull along the dorsal midline, which is proportionally similar
ARCHOSAURIFORMES Gauthier, Kluge, and Rowe, 1988 to Qianosuchus but still much shorter when compared with phy-
ARCHOSAURIA Cope, 1869 sensu Gauthier, 1986 tosaurs such as Parasuchus (Chatterjee, 1978) and Mystriosuchus
PSEUDOSUCHIA Zittel, 1887–1890 sensu Nesbitt, 2011 (Hungerbühler, 2002). The mandible is about 25 cm long from
POPOSAUROIDEA Nopcsa, 1923, sensu Nesbitt, 2011 the anterior tip to the end of the retroarticular process (right
DIANDONGOSUCHUS, gen. nov. side), being 13 cm shorter than that of Qianosuchus. All openings
or fossae are preserved on the left side of the skull, although
Type and Only Species——Diandongosuchus fuyuanensis, sp.
many of them are slightly distorted. The external naris should
nov.
have been an elongate oval in life, although it is distorted by the
Diagnosis——As for the type and only species.
anterior thrust of the anteroventral process of the nasal. The naris
Distribution——As for the type and only species.
is not terminal in position, but is placed at a level posterior to the
Etymology——The generic name is derived from ‘Diandong,’
sixth premaxillary tooth as in Qianosuchus, although it is smaller
indicating the easternmost part of Yunnan Province where the
than that of the latter. The relatively posterior position of the
specimen was collected.
naris is also comparable to the condition in the proterochampsian
DIANDONGOSUCHUS FUYUANENSIS, sp. nov. Chanaresuchus (MCZ 4039) and the pterosaur Eudimorphodon
(Figs. 1–6) (Wild, 1978), but the premaxillary portion anterior to the naris
bears fewer teeth in those taxa. The posterior margin of the naris
Holotype——ZMNH M8770, a nearly complete skeleton with is widely separated from the antorbital fossa as in many other
most of the caudal vertebrae missing. archosauriforms such as Proterosuchus (Cruickshank, 1972),
Locality and Horizon——West of Huangnihe River, south- Saurosuchus (Alcober, 2000), Postosuchus (Chatterjee, 1985),
east Fuyuan County, Yunnan Province; Zhuganpo Member (La- Sphenosuchus (Walker, 1990), and Dibothrosuchus (Wu and
dinian) of the Falang Formation, late Middle Triassic (Chen, Chatterjee, 1993); it differs from the condition in Qianosuchus
1985). and phytosaurs (Chatterjee, 1978; Hungerbühler, 2002; Stocker,
Etymology——The specific name refers to Fuyuan County, 2010) where the posterior margin of the naris extends beyond
where the holotype specimen was excavated. the anterior edge of the antorbital fenestra. The antorbital
Diagnosis——A small- to medium-sized poposauroid, differ- fossa is roughly triangular in outline, unlike the elongate oval
ing from other poposauroids in having the combination of the of Qianosuchus, and contains an elliptical antorbital fenestra
following derived character states: anterodorsal (nasal) process near the anteroventral corner as in the basal archosauriforms
of premaxilla extending posteriorly well beyond external naris; Proterosuchus, Erythrosuchus (Gower, 2003), and Euparkeria
presence of a fossa expanded in anteroventral corner of external (Ewer, 1965). The orbit is circular in outline and similar to that
naris; squamosal with supratemporal fossa in posterior portion of Aetosaurus (Schoch, 2007) but larger than the antorbital fossa.
and distinct ridge on dorsal surface along edge of supratempo- Circumorbital bones form an elevated rim that extends anteriorly
ral fossa; external naris neither terminal in position nor close to to the dorsal margin of the antorbital fossa and posteriorly to the
antorbital fossa; jugal with pronounced longitudinal ridge on lat- dorsal margin of the infratemporal fenestra: a similar condition
eral surface and anterior process much broader than the posterior is known in Saurosuchus, Chanaresuchus, Qianosuchus, and Tur-
process underlying anterior process of quadratojugal; supratem- fanosuchus (Wu et al., 2001). The supratemporal fossa is slightly
poral fossa present anterior to supratemporal fenestra; coracoid distorted by the anteromedial displacement of the squamosal. It
foramen super-sized and laterally bordered by scapula; ischium is smaller than the orbit, oval in shape, and diagonal in orienta-
with a strongly expanded medial portion anteroposteriorly longer tion with respect to the dorsal midline. The bones surrounding
than the proximodistal height of the bone; metatarsal IV the the supratemporal fossa form an elevated supratemporal rim
longest; narrowed anterior margin of cervical osteoderms deeply as for the orbit mentioned earlier. The supratemporal fenestra
concave; snout about 2.5 times longer than post-snout region occupies much of the lateral part of the supratemporal fossa. The
along dorsal midline of skull; premaxilla with nine teeth (shared infratemporal fenestra is distorted but may have been roughly
1066 JOURNAL OF VERTEBRATE PALEONTOLOGY, VOL. 32, NO. 5, 2012

FIGURE 1. Skeleton of Diandongosuchus fuyuanensis, gen. et sp. nov. (ZMNH M8770).

triangular in outline as in Qianosuchus and Riojasuchus (Sereno, palatal portion cannot be observed due to the occlusion of the
1991), with the anterior and ventral margins straight, the short mandible.
dorsal margin slightly arched, and the posterior margin projecting The nasal is the longest bone among the roof elements, ex-
strongly into the fenestra. The posttemporal fenestra is common tending posteriorly over the anterior border of the orbit. Its an-
in some archosauriforms such as phytosaurs (Hungerbühler, terior end is forked and its posterior end tapers. Of the two rami
2002) and aetosaurs (Schoch, 2007) but cannot be observed in of the anterior fork, the longer dorsal ramus forms the dorsal-
this specimen because of the flattening of the skull. The outline most margin of the external naris. The shorter ventral ramus
of the external mandibular fenestra is obscured due to damage, lines the posteroventral margin of the naris and meets the pre-
but the remaining edges suggest an elongate shape, unlike the maxilla to exclude the maxilla from the external naris: this condi-
triangular shape of the fenestra in Qianosuchus. tion is known in many archosaurs such as Gracilisuchus (Romer,
The premaxilla is much larger than in other archosauriforms 1972), Saurosuchus, and Sphenosuchus but not in other taxa such
except for phytosaurs (Chatterjee, 1978; Hungerbühler, 2002) as Qianosuchus, Xilousuchus (Wu, 1981; IVPP V6068), Batra-
and the pterosauromorph Eudimorphodon. It is most similar chotomus (Gower, 1999), and Aetosaurus. The nasals meet along
to that of Qianosuchus, the proterochampsian Chanaresuchus, the midline except for the anterior one-third; posteriorly, each
and the pseudosuchian Effigia (Nesbitt and Norell, 2006) in nasal sends a projection that wedges between the frontal and
that the portion anterior to the external naris is much longer prefrontal. The nasal has sutures with the premaxilla, maxilla,
than the posteroventral process. Its anterodorsal (nasal) pro- and lacrimal laterally to form a nearly straight line. The nasal-
cess is much larger than the posterodorsal (maxillary) process prefrontal suture has a weak convexity close to the nasal-lacrimal
and extends posteriorly well beyond the external naris as in suture. There are short ridges and grooves on the external surface
Eudimorphodon; this appears to be unique among the Pseudo- of the bone.
suchia. The dental margin of the premaxilla is noticeably con- The frontals are about one-third the length of the nasal. They
vex as in Qianosuchus and the phytosaur Smilosuchus (Nes- are widest in the interorbital region where the bones enter the
bitt, 2011:fig. 7J). Posteriorly, the base of the elongate nasal orbits; they narrow anteriorly and posteriorly, and are truncated
process forms the anterodorsal margin of the external naris, at both ends. The dorsal surface is extensively ornamented with
whereas the short maxillary process forms the anterior half of short ridges and grooves. A weak but distinct ridge parallels the
the ventral margin of the naris. There is a shallow fossa an- midline ridge on each frontal. Sutures with the nasal, prefrontal,
terior to the external naris on the lateral surface of the pre- postfrontal, and parietal are clearly marked. The ventral struc-
maxilla, which is absent in Qianosuchus and other members tures of the bone are not exposed.
of the Poposauroidea (sensu Nesbitt, 2011). The external sur- The parietals are short but widen posterolaterally. In dorsal
face is well ornamented by pit-grooves and short ridges. The view, the parietal comprises a portion of the skull roof, a recessed
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1067

FIGURE 2. Skull and mandible of Diandongosuchus fuyuanensis, gen. et sp. nov. (ZMNH M8770), in left dorsolateral (A) and right ventrolateral
(B) views.

part within the supratemporal fossa, and a posterolateral process. cipital edge and underlies the parietal process of the squamosal.
The roof portion is anteriorly broad and constricted in the in- Anterolaterally, the parietal meets the postorbital just anterior to
terfenestral region. The dorsal surface of the roof portion is ex- the supratemporal fossa, excluding the postfrontal from the lat-
tensively ornamented with short ridges and grooves, as on the ter. Both the occipital and ventral surfaces of the parietal are not
frontal. The recessed part forms most of the supratemporal fossa. exposed.
The posterolateral process is a thin layer of bone, nearly vertical The maxilla is slightly shorter but broader than the nasal in
in orientation; it forms the major part of the deeply incurved oc- dorsal view, and most similar to that of Proterosuchus in having
1068 JOURNAL OF VERTEBRATE PALEONTOLOGY, VOL. 32, NO. 5, 2012

FIGURE 3. Outlines of the skull and mandible of Diandongosuchus fuyuanensis, gen. et sp. nov. (ZMNH M8770), in left dorsolateral (A) and right
ventrolateral (B) views. See text for abbreviations.

a large antorbital portion. Anteriorly, the maxilla narrows and gin of the antorbital fossa. There is a longitudinal ridge along
meets the premaxilla posteroventral to the external naris. The the posteroventral margin of the antorbital fossa, which is the
dorsal process is triangular and posterodorsally directed; it forms anterior continuation of a ridge on the jugal (see below). The
the anterior border of the antorbital fossa, and the narrow tip lateral surface is uneven in the anterior portion, with pits, short
inserts between the nasal and the lacrimal. The posteroventral grooves, and ridges scattered around, but it becomes concave
process of the maxilla forms the anteroventral half of the mar- and weakly ornamented posteriorly. The dental margin is slightly
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1069

convex but distinctly concave near the suture with the premaxilla. and many other pseudosuchians such as Gracilisuchus, Effigia,
The maxilla-jugal suture is zigzagged and extends posteroven- and Arizonasaurus (Nesbitt, 2005) in having a very broad ante-
trally. The palatal shelf of the maxilla is not exposed. rior process and a narrow posterior process. The anterior end of
The triangular prefrontal most resembles that of Qianosuchus, the anterior process forms a fork and meets the maxilla ventrally
with a stout anterior process between the nasal and lacrimal and and the lacrimal dorsally. The dorsal edge of the anterior pro-
forming the anterodorsal rim of the orbit. The dorsal surface cess forms the ventral part of the pronounced orbital rim. The
is rugose, with distinct short ridges and grooves; among those posterior process is nearly as long as the anterior process but it
ridges, the one forming the part of the orbital rim is the most is dorsoventrally about half the broadness of the latter, and its
pronounced. The prefrontal does not enter the antorbital fossa. ventral edge is concave. Posteriorly, the process tapers and un-
Sutures with the nasal, lacrimal, and frontal are clearly marked. derlines the quadratojugal. The relatively short ascending pro-
The ventral portion (the descending pillar) is observed through cess directs dorsally and slightly posteriorly; the pointed distal tip
the orbit but cannot be detailed because of the flattening of the wraps the posterior side of the descending ramus of the postor-
skull. bital. In lateral view, there is a robust ridge that extends anteri-
The lacrimal is a roughly crescent-shaped bone and much orly to meet the antorbital rim but diminishes posteriorly before
larger than the prefrontal. In lateral view, the bone is much the jugal-quadratojugal suture. The external surface of the jugal
broader than in Qianosuchus. The large anterior part of the is smoothly concave ventral to this ridge.
bone is recessed in the antorbital fossa as in many archosauri- The quadratojugal is a plate-like bone, most similar to that
forms such as Euparkeria, Chanaresuchus, Gracilisuchus, and ae- of many phytosaurs such as Parasuchus and Mystriosuchus
tosaurs. The posterior portion posterior to the fossa is anteropos- (Hungerbühler, 2002). It lies decumbently at the posteroventral
teriorly narrow, with a strong ridge to form the anteroventral part corner of the skull. It is distinct in that its small jugal process is an-
of the orbital rim posteriorly and meet the elevated posteroven- teriorly forked and overlaps the jugal to form the posterior third
tral margin of the antorbital fossa ventrally. The recessed anterior of the ventral margin of the infratemporal fenestra. The main
part forms the posterior and dorsal borders of the antorbital fen- body of the quadratojugal has a prominence near the posterior
estra. The lacrimal foramen is situated at the lacrimal-prefrontal margin. The wide posterior edge of the bone abuts against the
suture slightly medial to the orbital rim. ventrolateral side of the quadrate. Posteroventrally, the quadra-
The postfrontal is well preserved on the right side, and its mor- tojugal appears to join the formation of the mandibular condyle.
phology is most similar to that of Euparkeria and Gracilisuchus. The external surface lacks ornamentations except for the promi-
It is triangular in outline, occupying the posterodorsal corner of nence near the posterior margin.
the orbital edge. Medially, the postfrontal meets the frontal and Exposure of the quadrate is limited due to compression. The
barely contacts the parietal. Posteriorly, the postfrontal meets the body is column-like, with a concave posterior margin and a tri-
postorbital and is excluded from the supratemporal fossa by the angular anterolateral process inserting between the descending
parietal-postorbital contact. The observable surface bears ridges process of the squamosal and the quadratojugal. The presence of
and grooves. the quadrate foramen is obscured by cracks along the boundary
The triradiate postorbital is generally similar to that of non- with the quadratojugal. The well-developed condyle is still articu-
crocodylomorph archosauriforms but distinct in that the poste- lated with the articular. The large dorsal cephalic head is capped
rior ramus is short and distally not sharply pointed. The dorsome- by the squamosal but laterally exposed as in Qianosuchus. The
dial ramus is distally pinched off and meets the parietal and the pterygoid ramus of the left quadrate is visible in the infratempo-
short posterior ramus meets the squamosal. In dorsal view, the ral fenestra, showing the slightly convex lateral surface; the me-
postorbital is recessed posteromedially to form the anterolateral dial surface, seen through the other side, is concave.
part of the supratemporal fossa and encloses the supratemporal The palatal elements are only partly observed in the antorbital
fenestra. The descending ramus is the largest and tapers off dis- fenestra, the orbit, and the infratemporal fenestra of the left side,
tally along the orbit. The posterodorsal portion of this ramus is and in ventral view on the right side. The anterolateral part of the
recessed as well to form the anterodorsal margin of the infratem- palatine is exposed in dorsal view in the antorbital fenestra; this
poral fenestra. The external surface of the postorbital consists of part shows an embayment in the anterior edge, which may repre-
grooves and ridges. sent the posterior margin of the internal choana. The pterygoid
The squamosal consists of four processes. It differs from that exposed in the orbit is mainly the palatal process of the bone in
of Qianosuchus and many other archosauriforms such as phy- dorsal view; the exposed part is broad and thin. The left ptery-
tosaurs, Gracilisuchus, Batrachotomus, and Turfanosuchus in goid partly overlaps the right pterygoid; the latter appears to be
that its stout anterior (postorbital) process is distally truncated folded but this may have been caused by severe distortion. The
and receives the narrow overlap of the postorbital anteriorly. The quadrate ramus of the left pterygoid is partly visible in the in-
anterior process forms the posterior portion of the upper tempo- fratemporal fenestra on the both sides. It is a sheet of bone nearly
ral bar. The posteromedial (parietal) process is nearly vertical in vertically oriented; its medial surface is concave and its posterior
orientation and distally thinned. These two processes are medi- end is overlapped by the pterygoid ramus of the quadrate. The
ally recessed to form the posterolateral part of the supratempo- transverse flange of the pterygoid is exposed on the right side;
ral fossa and enclose the supratemporal fenestra. The descending it is a massive process directed ventrally and slightly posteriorly,
process is the longest and is larger than that of Qianosuchus; it ta- and its lateral side is thickened. The ectopterygoid is completely
pers distally, projects anteroventrally into the infratemporal fen- exposed in ventral view, although it is broken into three pieces.
estra, and forms the majority of the posterior margin of the lat- It is a small bone that consists of a short but broad medial part
ter as in the ornithosuchid Riojasuchus. This process contacts the to contact the pterygoid flange and a long and distally pointed
quadrate posteriorly and the quadratojugal ventrally. The pos- posterolateral process that may have articulated with the max-
terolateral process is the smallest; it, together with the base of the illa and jugal. The ectopterygoid lacks an anterolateral process as
descending process, caps the dorsal head of the quadrate anteri- in many other pseudosuchians such as Postosuchus. Its anterior
orly and meets the paroccipital process of the exoccipital posteri- edge and ventral surface are slightly concave.
orly. The external surface of the squamosal is noticeably rugose, Small portions of the braincase can be observed through the
with pronounced ridges and grooves. No ventral structures of the orbit and the temporal fenestrae of the left side, and on the oc-
squamosal are exposed. cipital surface. The exposed parts in the supratemporal and the
The jugal is triradiate and shorter than the maxilla as in Pro- infratemporal fenestrae are barely visible owing to compression.
terosuchus and Qianosuchus. It differs from that of Qianosuchus The tongue-like process exposed in the posterodorsal corner of
1070 JOURNAL OF VERTEBRATE PALEONTOLOGY, VOL. 32, NO. 5, 2012

the orbit may be the anterior part of the parabasisphenoid pro- slightly convex dorsally and concave ventrally. Its relationships
cess in lateral view; it bears a midline groove on the dorsal sur- with other elements remain unknown.
face. A flat bone posterior to the parietal may represent the The rod-like bone just dorsal to the surangular-angular suture
supraoccipital. This bone bears a ridge along the dorsal midline, on the medial surface of the mandible on the left side is identi-
which disappears before reaching the ventral edge of the bone; fied as a segment of the left hyoid. It is structurally simple and
sutures with the parietal and exoccipital are ridged. The lateral somewhat curved posteriorly.
sides of the midline ridge are shallowly concave. The only part of The dentition of the upper jaw bears nine premaxillary teeth,
the exoccipital available for examination is the right paroccipital as in Qianosuchus, but only 15 maxillary teeth, three fewer
process, which contacts the cephalic head of the quadrate at its than in Qianosuchus. Most archosauriforms have five or fewer
lateral end. premaxillary teeth, although Proterosuchus and Archosaurus
The dentary is large and occupies over two-thirds of the total (Tatarinov, 1960) have six and phytosaurs have more than 10
mandibular length. It is anteriorly shallow and posteriorly deep. (Nesbitt, 2011). The teeth are similar to those of Qianosuchus
It appears that the posterior edge of the bone had three pro- and many other archosauriforms such as Proterosuchus, Shan-
cesses: one meeting the surangular and two binding the angular. sisuchus (Young, 1964), Fugusuchus (Cheng, 1980), Saurosuchus,
The dorsal two processes form the anterior border of the external and Postosuchus, exhibiting typical carnivorous archosauriform
mandibular fenestra. In lateral view, the bone surface is uneven, tooth morphology. They are homodont in morphology but het-
especially in the anterior half, and extensively ornamented by erodont in size. All of the upper teeth are dagger-like and curve
longitudinal pit-grooves and ridges. The occlusal margin is mostly posteriorly. They are serrated along the anterior and posterior
covered by the upper jaw and teeth; the ventral edge of the bone carinae; the serrations extend along the entire posterior carina,
is nearly straight. The symphysis is displaced and the left facet is but only the apical portion of the anterior carina, especially in
exposed. The dentary is tightly articulated with the splenial on functional teeth. Both the lingual and the labial surfaces of the
the medial side, and their sutures are hardly recognizable. teeth are slightly convex. Among the nine premaxillary teeth
The left surangular is better preserved than the right. It is of the right side, the fifth tooth is the largest and located at
forked anteriorly and the ventral process of the fork may have the peak of the convex dental edge, and the ninth tooth is the
joined in the anterodorsal border of the external mandibular fen- smallest. Dentary teeth are similar to those of the upper jaw in
estra. The dorsal process of the anterior fork is more slender than both shape and size variation. The exact number of the den-
the ventral process but not completely exposed, which obscures tary teeth remains unknown because of the occlusion of the
the presence or the absence of the anterior foramen seen in Pro- jaws.
terosuchus and Euparkeria. Posteriorly, the surangular broadens
and extends to the end of the retroarticular process, as in many
Vertebral Column
pseudosuchians such as aetosaurs (Schoch, 2007), Effigia, and
Sphenosuchus. The lateral surface of the bone is ornamented with The vertebral column is articulated with the skull (Fig. 1). The
ridges, including a short ridge along the posterodorsal margin, a anterior end is overlapped by the occiput so that the elements
relatively long ridge dorsal to the suture with the angular, and a of the atlas and the proatlas are poorly exposed. The vertebral
short and curved ridge around the articular fossa. The posterior centra are severely flattened, exaggerating vertebral height. The
surangular foramen seen in the aforementioned two archosauri- preserved vertebral column consists of 25 presacral, two sacral,
forms (Nesbitt, 2011) is present but the presence of the foramen and the first seven caudal vertebrae (Fig. 4B).
is obscured on the right surangular owing to surface damage. The The plate-like proatlas is displaced towards the left side. It is
dorsal margin of the bone is slightly convex. Medially, the adduc- largely covered by the skull and its entire outline cannot be de-
tor chamber is broad but shallow, which may have been exagger- termined (Figs. 2, 3). Elements of the atlas are disarticulated and
ated by the flattening. represented by the intercentrum and the left atlantal neural arch.
The angular is incomplete on both sides. Anteriorly, it pinches The intercentrum exposed with the skull on the left side is pre-
off into a sharp process to underlie the posteroventral process served in ventral view, but detailed morphology is not available
of the dentary laterally and meet the splenial medially, as in because of the overlying quadrate. The partly exposed medial
Qianosuchus and other archosauriforms such as Proterosuchus, surface of the preserved right neural arch is significantly concave
Gracilisuchus, and Batrachotomus. Posteriorly, the bone narrows and its dorsal spine is longitudinally broad, with a tip bending
and extends posteriorly close to the end of the retroarticular pro- medially (Fig. 3B).
cess. Posteromedially, the angular forms the ventral border of the The axis is characterized by a high and broad neural spine, of
adductor chamber. which the dorsal margin is nearly straight (Fig. 4A); the axial neu-
The left articular is well exposed in medial view. It is a stout ral arch is posterodorsally expanded, arched, or concave in other
bone, barely visible in lateral view owing to the surangular and archosauriforms such as Chanaresuchus, Arizonasaurus, Batra-
the angular. In medial view, the articular fossa broadens medi- chotomus (Gower, 2009), Gracilisuchus, or Postosuchus. The an-
ally, and there is a ridge just ventral to the fossa. In posterior terior portion of the spine is not observable (Figs. 2–4). The pos-
view, the retroarticular process is short but robust, with a short terior margin of the axial spine is notably concave. The odontoid
medial process broadening the dorsal surface of the process. The process is disarticulated from the axial centrum; the latter is rela-
retroarticular process faces posteriorly and slightly dorsally and tively short and laterally concave. The postzygapophysis is much
bears a fossa that is further divided longitudinally by a weak sep- more pronounced than the prezygapophysis. Much of the neuro-
tum. The distal end of the retroarticular process tilts downward central suture is untraceable, indicating that the specimen is at
and is much lower than the articular fossa in position. least a young adult (Brochu, 1996).
The splenial is a large bone and more extensively exposed on Cervical vertebrae 3–7 are well exposed in right lateral view
the left side than the right. It is tightly articulated with the den- (Fig. 4A), and differ from those of Qianosuchus in their shorter
tary on the medial surface of the mandible. Relationships with centra and taller neural spines, as indicated by the following ra-
the neighboring elements are obscured by poor preservation and tios. In Qianosuchus, the centrum of cervical 5 is about 2.9 times
it is uncertain whether it joined the mandibular symphysis. longer than that of dorsal 13 and the neural spine height of
The left prearticular was displaced from the ventral margin of cervical 5 (dorsal to the prezygapophysis) reaches about 0.46
the mandible to the posterodorsal edge on the medial surface. of the total vertebral length (IVPP V143000). However, these
It is a strap of bone, with both ends slightly broadened. It is ratios are 0.93 and 1.0, respectively, in Diandongosuchus. All of
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1071

FIGURE 4. Cervical and first seven caudal vertebrae, and the related osteoderms of Diandongosuchus fuyuanensis, gen. et sp. nov. (ZMNH M8770),
in lateral views. Note that the cervical (A) and the posterior six caudal (B) pairs of osteoderms are preserved in ventral view but that the first
15 pairs of the caudal osteoderms (B) are in dorsal view. C, a close-up of the 16th to 18th caudal osteoderms in ventral view. See the text for
abbreviations.

the cervicals of Diandongosuchus are similar in morphology but lacks the dorsally positioned fossa seen in Turfanosuchus (Wu
differ in the details of the neural spine. The spine is distinctly et al., 2001). The diapophysis and the parapophysis of each ver-
narrower in cervical 3 than in the others. The distal surface of tebra gradually move dorsally and posteriorly between cervicals
the neural spine in cervicals 4–7 is transversely broad to receive 3–7. The total length of cervical centra 3–5 reaches 53 mm. Most
osteoderms. The lateral surface of the centrum is concave but of the last two cervicals and the first dorsal is covered by the
1072 JOURNAL OF VERTEBRATE PALEONTOLOGY, VOL. 32, NO. 5, 2012

TABLE 1. Selected measurements (in mm) of Diandongosuchus fuyua- Ribs, Gastralia, and Chevrons
nensis, gen. et sp. nov. (ZMNH M8770).
Single-headed ribs of the atlas and axis are elongate and rod-
Measurements like but still much thicker and shorter than those in Qianosuchus
(Figs. 3, 4A). From the third cervical vertebra, the ribs are short
Length of skull and dichocephalous. Both the capitulum and the tuberculum
(to quadrate condyle) 240 curve strongly inward from the shaft. There is an anterior (mid-
Length of mandible
(to retroarticular process) 250 dle) process between the capitulum and the tuberculum, which is
Vertebral length pointed and free distally. It is possible that cervical rib 9 still has
3 to 5 53 this process. Whether or not the anterior process is retained in
10 17 the first dorsal rib cannot be confirmed due to the overlying pec-
13 18 toral girdle. The dorsal ribs are slender and curved when com-
17 20.5 plete. The last dorsal rib is short; it appears incomplete and its
21 + 22 42
Two sacrals 43 expanded distal end might be the result of preservation. Judg-
Caudal 1 21 ing from the proximal width, the second sacral rib is the most
Interclavicle massive, with a strongly expanded distal end (Fig. 6A). The first
Length 91 sacral rib is not completely exposed but its proximal width sug-
Anterior width 32 gests that this rib is slightly less massive than the second. On the
Length of left humerus 104
Length of left radius 82
medial surface of the left ilium, facets for the two sacral ribs are
Length of left ulna 86 exposed near the base of the iliac blade. The sacral ribs are more
Length of right femur 140 or less displaced from their centra, indicating a loose connection
Length of fibula 112 (R), 112 (L) between the sacral ribs and the vertebral column.
Length of tibia 110 (R), 113 (L) Gastralia are loosely articulated and displaced from their orig-
Length of metatarsals (left) I: 29 inal position (Figs. 1, 5). A complete set of gastralia consists of an
II: 41
III: 44 angled central segment and two pairs of the lateral segments. The
IV: 52 interior angle of the central segment is smaller than 80 degrees in
V: ? the first two or three sets but exceeds 90 degrees in the posterior
sets.
Abbreviations: R, right; L, left. There are three chevrons preserved posterior to the fifth cau-
dal vertebra but none of them is complete (Fig. 4B). That be-
tween the fourth and fifth caudals is the most complete but is
missing its distal symphysis, and its forked proximal part is lightly
pectoral girdle; the exposed anteroventral part of the eighth
built. The chevrons are articulated with the preceding centrum, as
centrum shows that the parapophysis is still quite low in position.
in Qianosuchus. Morphology of the posteroventral edges of the
All dorsal vertebrae are exposed in ventrolateral view with
second and the third centra indicates that the first chevron should
their neural spines buried in the matrix and ribs and gastralia cov-
have been attached to the third caudal vertebra.
ering most of them (Figs. 1, 5). From dorsal 2, the diapophysis
becomes more pronounced than the parapophysis. These two rib
Pectoral Girdle and Forelimbs
facets are separated in the first four dorsals, but they shift upward
onto the neural arch. As in Qianosuchus, the centra of these dor- Elements of the pectoral girdle are partly articulated or closely
sals are laterally concave but do not form a rimmed fossa such associated with one another (Figs. 1, 5A). The right scapula is
as that seen in Koilamasuchus from the Lower Triassic of Ar- nearly completely exposed in external view. It bears a tall but
gentina (Ezcurra et al., 2010). The centra become longer towards narrow dorsal blade, in contrast to the low and broad blade in
the sacrum (see Table 1). Qianosuchus. The blade also differs from those of many other ar-
There are two sacral vertebrae as in Qianosuchus and many chosauriforms, such as Ticinosuchus (Krebs, 1965), Postosuchus,
other pseudosuchians such as Gracilisuchus, Postosuchus, and and Batrachotomus, but is similar to that of the phytosaur Smilo-
Sphenosuchus. The sacrals are exposed only in ventrolateral view suchus (Long and Murry, 1995; Nesbitt, 2011:fig. 30A) in that the
and the neural spines are hidden in the slab. The two sacrals reach thinned anterior margin is not evenly concave but concavocon-
a total length of 43 mm, of which the second is slightly longer than vex, with the anteroventral margin strongly projecting out. The
the first. Their centra are slightly concave, with a smooth ventral acromion process is not as pronounced as in Smilosuchus. The
surface. distal end of the blade is moderately expanded, but it is unclear
Of the preserved caudal vertebrae, the first six are nearly com- whether it is broader than the proximal portion due to the over-
plete but the seventh is missing the posterior half of the cen- lying humerus. A pit rather than a tuber for the M. triceps brachii
trum. The caudals are very different from those of Qianosuchus is evident just dorsal to the glenoid facet. Proximally, the scapula
in having much shorter neural spines, which (dorsal to the prezy- partly articulates with the coracoid, with a concave articular facet.
gapophysis) are about 0.56 of the total height of the vertebra The lateral surface of the scapula is slightly convex in the dorsal
in caudal 5 of Diandongosuchus, but this ratio is about 0.66 in blade but concave in the proximal portion, the latter situation is
Qianosuchus (IVPP V143000). The lateral surface of the cen- exaggerated by a vertical crack.
trum in the first six caudals is concave. The exposed ventral sur- The right coracoid is nearly complete and exposed in external
face of the third centrum shows a longitudinal trough along the view, with its medial portion covered by the interclavicle and the
midline (Fig. 4B). The transverse process is bar-shaped and com- anterolateral edge slightly damaged. It does not have the post-
plete in caudals 2–4. The neural spine is totally exposed in caudals glenoid process seen in Qianosuchus and many other archosaurs
5–7 and is moderately broad (about half the length of centrum) such as the ornithosuchid Ornithosuchus (Walker, 1964) and
and directed dorsally and slightly posteriorly. There is a vertical basal crocodylomorphs (Dibothrosuchus, Sphenosuchus), but is
ridge, derived from the dorsal surface of the postzygapophysis, characterized by an embayment-shaped anterior notch facing the
on the lateral surface of the spine, which becomes indistinct be- scapula. As shown by the dashed line in Figure 5A, the coracoid
fore reaching the distal margin of the spine. Whether or not this may have had an arched or convex medial margin. The coracoidal
ridge is present in all caudal vertebrae is uncertain because the glenoid facet is larger than its counterpart in the scapula. The ex-
majority of the tail is missing. ternal surface of the right coracoid is concavoconvex, whereas its
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1073

FIGURE 5. Pectoral girdle and the forelimbs of Diandongosuchus fuyuanensis, gen. et sp. nov. (ZMNH M8770). A, pectoral girdle and humeri (see
text for the orientation of each element); B, left ulna and the radius in lateral view; C, reconstruction of the right coracoid and the proximal portion of
the right scapula, showing the super-sized coracoid foramen; D, left hand in ventral view. See text for abbreviations.

internal surface is concave (seen in the left bone), although ex- The right clavicle is exposed in posteromedial view. Facets for
tensively flattened during preservation. the scapula and the interclavicle are clearly marked. The inter-
As indicated by the right scapula and coracoid, the adjoined clavicle is exposed in dorsal view; it is slightly damaged at its right
articular portions of the two bones are not anteroposteriorly anterolateral corner. It is sword-shaped, with a weakly devel-
equally wide, but are narrower in the former and broader in oped anterolateral process and a short anterior process as seen in
the latter. It is clear that the scapula width was reduced ow- phytosaurs such as Smilosuchus (Nesbitt, 2011) and Parasuchus,
ing to a fold caused by the vertical crack and the coracoid and some other archosaurs such as Revueltosaurus (Parker et al.,
was broadened slightly due to dorsoventral flattening. There- 2005), Ornithosuchus, and Sphenosuchus. The body is slightly bi-
fore, as reconstructed, the proximal portions of both bones laterally constricted, with a sharply pointed posterior end. Artic-
should have been similar in width and the large anterior notch ular facets on the anteromedial surface of the interclavicle sug-
of the coracoid should have been bordered by the scapula gest that two clavicles approached midline but did not meet each
(Fig. 5C). The enclosed coracoid notch may have included or other medially.
even just represented an enlarged coracoid foramen. Such a Both forelimbs are fairly well preserved, only missing the
super-sized coracoid foramen appears to be unique within the carpals and some phalanges of the right manus (Fig. 5). The
Archosauria. right humerus is exposed in anteromedial view and the left in
1074 JOURNAL OF VERTEBRATE PALEONTOLOGY, VOL. 32, NO. 5, 2012

FIGURE 6. Pelvic region and hind limbs of Diandongosuchus fuyuanensis, gen. et sp. nov. (ZMNH M8770). A, pelvic region (see text for the orien-
tation of each sacral element); B, left tibia, fibula, and pes in posteroventral view; C, right femur in posteromedial view; D, right pes in posteroventral
view; E, right femur in posteromedial view. See text for abbreviations.
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1075

posterolateral view. Both ends of the humerus are strongly ex- in posteromedial view and resembles that of Qianosuchus and
panded; it differs from that of Batrachotomus and Turfanosuchus some Triassic archosaurs such as Turfanosuchus, Ticinosuchus,
shageduensis (Wu, 1982) in that the proximal end is wider than and Batrachotomus, with a slightly sigmoid and twisted shaft so
the distal end. The shaft is straight and constricted asymmetri- that the proximal head and the distal condyle are not in the
cally so that the proximal head of the bone directs posterome- same plane. The femoral head is not ball-shaped and does not
dially. Distally, the medial articular condyle is larger than the strongly bend anteriorly to form a fold. The fourth trochanter,
lateral one. The posterolateral surface of the humerus is slightly located near the proximal third of the total length, is pronounced
convex. Medially, the deltopectoral process is moderately devel- but was compressed during fossilization. The moderately devel-
oped along the anterolateral edge, at the proximal quarter of the oped distal condyle does not project markedly beyond the shaft.
total length of the bone. The medial surface is distinctly concave, The medial surface of the shaft is concave. Both the tibia and
especially in the proximal quarter. The left ulna and radius are the fibula are exposed in posteroventral view (Fig. 6B) and are
well exposed in medial view (Fig. 5B). They are similar to those of proportionally shorter (about 80% the length of the femur) than
extant crocodylians such as Alligator sinensis (Cong et al., 1998) in Qianosuchus (about 84% the length of the femur), but much
in that the olecranon process of the ulna is not well developed longer than in phytosaurs such as Parasuchus (where this ratio is
and the ulna is slightly longer and much thicker than the radius. about 64%; Chatterjee, 1978). The tibia is massive and the prox-
The ulnar shaft is slightly sigmoidal, with the proximal end much imal end is more expanded than the distal end. The tibial shaft is
wider than the distal end. The radius is essentially bar-like, with straight and symmetrically constricted. The facets for the femur
its ulnar margin weakly concave. As with the ulna, the medial sur- and the astragalus are concave. The fibula is relatively much thin-
face of the radius is slightly concave. The carpus is represented ner and more sigmoid than in Qianosuchus, and is slightly longer
by two carpals (Fig. 5B, D); the one displaced proximally is prob- than the tibia (see Table 1). The posteroventral surface of the
ably the radiale, which is asymmetrically rectangular in outline, fibula is concave.
and the other still articulated with metacarpal IV is probably the There are four tarsals in each foot; they are the calcaneum,
fused distal carpals 3+4. Metacarpals I to IV are preserved. The astragalus, and separate distal tarsals 3 and 4, all exposed in pos-
first and the second are partly exposed and their exact lengths terior view (Fig. 6B, D). The calcaneum and the astragalus form
remain unclear, and the third and fourth are fully exposed (Fig. a ball-and-socket articulation as in many other pseudosuchians
5D). The first metatarsal appears the shortest but thickest among (see below). The dorsolaterally directed calcaneal tuber is pro-
the preserved four. The second is longer than the first but shorter nounced and the calcaneal condyle is well developed and roller-
than the third and the fourth, the latter two are similar in length shaped; the facets for the third and fourth distal tarsals and the
and thickness. There are 10 or 11 phalanges preserved, of which fibula are continuous. The facet for the astragalus on the an-
one is a laterally compressed claw with a pointed distal end. teromedial side, as well as its relationships with the hemicylin-
The phalanges are disarticulated and the phalangeal formula is drical condyle, cannot be observed. Posteriorly, the calcaneum
unknown. is strongly concave, and its large tuber is distally expanded and
faces posterolaterally.
The astragalus is characterized by a well-developed peg, which
Pelvic Girdle and Hind Limbs
suggests that a socket was present in the calcaneum to form a
The preserved elements of the pelvic girdle are disarticulated, crocodile-normal tarsal joint. In posterior view, the dorsal facet
and some are partly covered by other bones (Fig. 6A). The for the fibula is small and separated by a sharp ridge from the
right ilium in lateral view is better exposed than the left (in me- tibial facet that is large and slightly concave and flexed. The pos-
dial view), and the acetabular fossa is largely overlapped by the terior surface of the astragalus is concave but divided by a weak
femoral head. The iliac blade is spike-like, dorsoventrally nar- ridge. The ventral facets for metatarsals I and II appear convex
row, and anteroposteriorly long; it is more posterodorsally di- (see the right pes). Distal tarsals 3 and 4 are sutured, instead of
rected than in Qianosuchus and many other archosaurs such as being separated from each other as in Postosuchus; and the third
Batrachotomus. The presence of a preacetabular process seen in is smaller than the fourth.
many other archosaurs remains unclear. The articular facets for All metatarsals are preserved and the first four are complete
the pubis and the ischium are similar in size, and their long axes in the left foot. These four are similar in thickness and are suc-
form a wide angle of about 130 degrees in lateral view. The prox- cessively longer from the first to the fourth; in other words,
imal portion of the left ilium shows a convex medial surface on metatarsal IV is the longest, which differs from Qianosuchus and
which rib facets are clearly marked. The right pubis is exposed in many other archosaurs such as Ticinosuchus and Batrachotomus
medial view and is more complete than the left. It differs from in which metatarsal III is the longest. The new taxon also dif-
those of many other archosaurs, except for Qianosuchus, in that fers from Qianosuchus in that metatarsals II and IV are similar
the distal portion is wider than the proximal portion, and that in length in the latter. In Diandongosuchus, the fifth metatarsal is
the ischial facet is smaller than the iliac facet and is hook-like more expanded proximally than the others; it is incomplete dis-
in lateral view. The better-preserved left ischium is slightly dam- tally and its total length is unknown. The medial side of the prox-
aged along the anterior margin. The bone is characterized by a imal end of the fifth metatarsal articulates with the lateral side of
distal/medial portion that is much more expanded than the prox- distal tarsal 4 as shown in the left foot, which indicates that the
imal portion and anteroposteriorly longer than the proximodistal fifth may have been hooked in life. There are seven phalanges
height of the bone (Fig. 6A). It differs from that of Qianosuchus preserved in the left pes, and the first and the second digits bear
and other archosaurs such as Arizonasaurus (Nesbitt, 2011:fig. two and three phalanges, respectively, as in Qianosuchus. The
33D) and Poposaurus (Schachner et al., 2011:fig. 6C, D) in which phalangeal count is unknown for the other digits.
the distal portion of the bone is not so expanded and the posterior
margin is not so strongly concave. The ischium of phytosaurs ap-
Osteoderms
pears expanded in both dorsal and distal portions, but to a lesser
degree (especially the distal portion), and its posterior margin is From the axis to the sixth cervical vertebra, two rows of seven
weakly concave (Chatterjee, 1978:fig. 12a). The facet for the il- and a half osteoderms are exposed in ventral view. They are
ium is clear, but that for the pubis is incomplete. The ischium is associated with the neural spines of the five vertebrae, indicat-
shorter but distally broader than the pubis. ing one and a half pairs of osteoderms per vertebra (Fig. 4A).
Many elements of both hind limbs are complete except for the Each osteoderm overlaps the anterior margin of the succeeding
metatarsals and the phalanges (Fig. 6). The right femur is exposed one, and the first set of the osteoderms is smaller than the rest.
1076 JOURNAL OF VERTEBRATE PALEONTOLOGY, VOL. 32, NO. 5, 2012

All osteoderms are asymmetrically oval in outline, with a narrow Vancleavea, Chanaresuchus, and Eudimorphodon, the scoring of
anterior portion that is evidently notched from the third. As pre- character 139 was changed from state 0 to 1; for the three phy-
served, most of the dorsal osteoderms of the trunk are covered by tosaurs included, character 6 was emended from state 3 to 6; and
the body, but the last five of the right row are exposed in dorsal five characters were rescored for Qianosuchus, namely charac-
view, covering the posterior-most two dorsal vertebrae and the ter 6 (changed from state 2 to 5), character 139 (changed from
anterior portion of the first sacral vertebra. This indicates that state 0 to 2), character 207 (changed from state 1 to 0), charac-
there are two pairs of osteoderms per dorsal vertebra. These os- ter 218 (changed from state 0 to 2), and character 273 (changed
teoderms are connected with one another in a pattern as seen in from state 2 to ?). For full details of the modifications made to
the cervical series. They have a slightly narrowed posterior por- the data matrix, see Supplementary Data (available online at
tion, a longitudinal dorsal thickening, and an anterolateral pro- www.tandfonline.com/UJVP).
cess. Their dorsal surface is ornamented by numerous pits. The Nesbitt (2011:appendix 3) originally scored 412 characters
exposed portion of the dorsal osteoderms is roughly rectangular for 83 taxa, but the phylogenetic analysis he presented was
in outline. based on a data matrix including only 77 taxa, with 6 taxa ex-
Caudal osteoderms are well preserved along the dorsal side of cluded (the proterosuchid Archosaurus, three representatives of
the caudal neural spines, and similarly connected to each other Prestosuchus [UFRGS 156T, UFRGS 152T, and a combined
as in the more anterior series (Figs. 4B, 6A). There are about 21 Prestosuchus OTU], and two dinosauriforms [Pseudolagosuchus
pairs of caudal osteoderms preserved from the last sacral verte- and combined Lewisuchus/Pseudolagosuchus]). Following Nes-
bra, of which the anterior 15 and a half pairs are exposed in dor- bitt (2011), the six above-mentioned OTUs were excluded from
sal view and cover the first seven caudal vertebrae; the remain- an analysis of his pruned data set that was expanded to include
ing posterior seven pairs are preserved in ventral view. Again, Diandongosuchus (thus comprising 78 taxa and 412 characters):
each caudal vertebra is at least covered by two pairs of osteo- this analysis was run with 18 ordered multistate characters (32,
derms. The anterior 15 pairs appear similar to the posterior dor- 52, 121, 137, 139, 156, 168, 188, 223, 243, 258, 269, 271, 291, 297,
sal osteoderms in morphology. The osteoderms in the posterior 328, 356, and 399) and was performed using a heuristic search in
seven pairs have a pointed anterior portion and a smooth ven- PAUP∗ 4.0b10 (Swofford, 2002). It yielded 14,040 most parsimo-
tral surface (Fig. 4C). As in extant crocodilians and some basal nious trees (MPTs) with tree lengths (TL) of 1345 steps, consis-
archosaurs such as aetosaurs (Schoch, 2007), osteoderms cover tency index (CI) of 0.3636, and retention index (RI) of 0.7615. As
both the forelimbs and the hind limbs. The preserved limb osteo- shown in the strict consensus of the 14,040 MPTs (Fig. 7A), the
derms are associated with the humerus, radius, and femur (Figs. interrelationships of Diandongosuchus are well established: it is
5, 6). They are small and oval in outline, and have a convex dorsal a pseudosuchian, the basal-most member of Poposauroidea, and
surface. its position is supported by 17 synapomorphies (ACCTRAN), in-
cluding five unequivocal character states. As for the other taxa
Stomach Contents in this analysis, their interrelationships are largely comparable to
those recovered by Nesbitt (2011) except for those of Ornitho-
Within the rib cage, there are bone fragments of small verte-
suchidae, Ticinosuchus, and some taxa within Paracrocodylomor-
brates concentrated just anterior to the pelvis (Figs. 1, 5A). These
pha and Ornithodira. In the new analysis, the Ornithosuchidae
are considered as stomach contents. None of the elements are
was not recovered as the basal-most group of the Pseudosuchia or
identifiable, with the exception of a fish vertebra. There is no
the sister group of Suchia (sensu Nesbitt, 2011), but formed un-
doubt that Diandongosuchus included fishes in its diet, although
resolved interrelationships with four basal pseudosuchians (Gra-
it is uncertain to which fish taxon the vertebra belongs and it is
cilisuchus, Turfanosuchus, Aetosauria [sensu Nesbitt, 2011], and
not clear if the fish was freshwater or marine at present.
the Paracrocodylomorpha [sensu Nesbitt, 2011]); Ticinosuchus
was not resolved as the sister group of the Paracrocodylomor-
PHYLOGENETIC RELATIONSHIPS
pha, but moved to become the basal-most member of Loricata
Phylogenetic relationships within the Archosauria and Ar- (sensu Nesbitt, 2011). With the alternative position of the Or-
chosauriformes have been analyzed in many papers, with nithosuchidae, the contents of the clades Suchia (node-based)
particular emphasis on the Avemetatarsalia and Pseudo- and the Pseudosuchia (stem-based) remained the same in this
suchia/Crurotarsi (see Brusatte et al., 2010; Nesbitt, 2011). A analysis as defined by Nesbitt (2011). The interrelationships of
number of recent studies (Gower and Nesbitt, 2006; Nesbitt, the paracrocodylomorph Saurosuchus and the crocodyliforms
2007; Weinbaum and Hungerbühler, 2007; Dilkes and Sues, 2009; Orthosuchus, Protosuchus, and Alligator are not exactly same as
Nesbitt et al., 2009; Desojo et al., 2011; Ezcurra et al., 2010) in Nesbitt (2011). Within the Ornithodira, only the interrelation-
dealt with relationships within specific archosaur or archosauri- ships of the ornithischians Pisanasaurus and Heterodontosaurus
form groups, but Brusatte et al. (2010) and Nesbitt (2011) are and the theropod Staurikosaurus are slightly different in this anal-
the only two recent studies in which the Archosauria as a whole ysis (see Fig. S1A in Supplementary Data). For comparison, we
was subjected to analysis. In the following phylogenetic study of re-ran this data matrix a second time with all multistate charac-
Diandongosuchus, our data matrix was derived from that of Nes- ters unordered. The results of this second analysis were almost
bitt (2011), which is much larger than that of Brusatte et al. (2010) identical to those from the first analysis, with minor differences
and the most complete data matrix among existing phylogenetic in the tree indexes (14,040 MPTs with TL of 1338 steps, CI of
studies of the Archosauriformes. 0.3655, and RI of 0.7581): the poposauroid status of Diandon-
In this study, we ran four analyses of two data sets to evaluate gosuchus is supported by 18 synapomorphies, including five un-
the effect of Diandongosuchus, four other operational taxonomic equivocal character states.
units (OTUs) (Archosaurus, UFRGS 156T, UFRGS 152T, and To test the effect of the four single-specimen OTUs excluded
Pseudolagosuchus) that were originally listed by Nesbitt in his by Nesbitt (2011), we included these in a second expanded data
2011 data matrix), and the ordering of character states in multi- set (now with 82 taxa and 412 characters, including Diandongo-
state characters on the resulting tree topologies. With the addi- suchus). An analysis was carried out using a heuristic search in
tion of Diandongosuchus, the data matrix comprises 82 taxa and PAUP∗ 4.0b10, with the aforementioned 18 multistate characters
412 characters. Compared with the original data matrix of Nes- ordered. This yielded 105,300 MPTs, with TL of 1355 steps, CI
bitt (2011), two new character states (5, 6) and one new character of 0.3616, and RI of 0.7637. As shown in Figure 7B, the topology
state (2) were introduced for characters 6 and 218, respectively. of the strict consensus tree of the 105,300 MPTs is more simi-
The scoring of some characters was altered for several taxa: for lar to that of Nesbitt (2011:figs. 51, 52) than to that recovered by
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1077

FIGURE 7. Cladograms depicting archosaur relationships (with no avian-line forms) based on the data matrix derived from Nesbitt (2011). A, the
strict consensus tree of 14,040 MPTs obtained by the analyses of 78 taxa and 412 characters (see text for details); B, the strict consensus tree of 105,300
MPTs yielded by the analyses of 82 taxa and 412 characters (see the text for details). Key: Hesperosuchus-A and Hesperosuchus-”A”, Heperosuchus
agilis and Hesperosuchus “agilis”; Polonosuchus-S, Polonosuchus silesiacus; Postosuchus-K and Postosuchus-A, Postosuchus kirkpatricki and Post-
suchus alisonae; Poposaurus-GH and Poposaurus-GY, Poposaurus gracilis (holotype) and Poposaurus gracilis (Yale specimen); Protosuchus-H and
Protosuchus-R, Protosuchus haughtoni and Protosuchus richardsoni. Synapomorphies, as optimized under accelerated (ACCTRAN) transformation
assumptions in tree 1 of the 105,300 MPTs, are listed for Proterochampsia, Phytosauria, and the other major archosaur clades (see Appendix 1).
1078 JOURNAL OF VERTEBRATE PALEONTOLOGY, VOL. 32, NO. 5, 2012

the above-mentioned analyses excluding these taxa; i.e., Ornitho- Desojo et al. (2011) in which Qianosuchus was hypothesized to
suchidae was identified as the basal-most group within Pseudo- be more basal than the Phytosauria (represented by Parasuchus)
suchia or the sister group of Suchia. As for Diandongosuchus, within Crurotarsi. In addition, our inclusion of Diandongosuchus
its interrelationships with other pseudosuchians did not change did not alter the non-archosaurian status of the Phytosauria,
and its poposauroid status was supported by 18 synapomorphies, which was hypothesized by Nesbitt (2011).
including five unequivocal character states. The loricatan status Diandongosuchus appears to be unique within Pseudosuchia
of Ticinosuchus within Paracrocodylomorpha is very stable in in the following features: a nasal process of the premaxilla that
this analysis, still differing from its position in the study of Nes- extends posteriorly well beyond the external naris, a super-sized
bitt (2011). Within Ornithodira, Lewisuchus was not recovered coracoid foramen laterally bordered by the scapula, a broadly
as a member of Silesauridae (contra Nesbitt, 2011), but formed expanded medial portion of the ischium, and the cervical os-
a polytomy with a less inclusive Silesauridae, Pseudolagosuchus, teoderms that are anteriorly notched. Besides the aforemen-
and Dinosauria (see Fig. S1B in Supplementary Data). A second tioned character states, our study also suggests that Diandon-
analysis of this data set, with the 18 multistate characters run un- gosuchus is apomorphic in more than 15 character states within
ordered, also produced 105,300 MPTs and their consensus tree Poposauroidea. Of those character states, the following nine are
showed the same interrelationships as derived from the first anal- the most convincing and form part of the diagnosis of the new
ysis of this data set, differing only in some of tree indexes, with taxon because their alternative states are known in all or most
TL of 1349 steps (six steps shorter), CI of 0.3632 (higher), and RI of the taxa within the clade: characters 9(1), 49(1), 55(1), 71(1),
of 0.7601 (lower). The poposauroid status of Diandongosuchus 75(1), 139(1), 144(1), 337(0), and 393(0).
is supported by 17 synapomorphies, including five unequivocal Diandongosuchus is the second archosaur from the marine de-
character states. posits of southwest China. As mentioned earlier, it shows no ob-
Although the numbers of the synapomorphies supporting the vious specializations to an aquatic way of life. However, (1) the
poposauroid status of Diandongosuchus within Pseudosuchia relatively posterior positioned external naris, (2) the ornamented
vary between the four analyses, the five unequivocal synapo- skull roof elements, and (3) the large number of the premaxillary
morphies are consistently the same in all of them. They are (1) teeth are not common in fully terrestrial archosaurs, but are seen
the length of the anterodorsal (nasal) process of the premaxilla in Qianosuchus (1, 3), Chanaresuchus (1), and the spinosaurid di-
greater than the anteroposterior length of the premaxilla, char- nosaurs (3), which were considered to be semiaquatic (Romer,
acter 1(1); (2) the posterior (maxillary or subnarial) process of 1971; Sereno et al., 1998; Li et al., 2006; Amiot et al., 2010). As to
the premaxilla restricted to the ventral border of the external the skull ornamentation, the pattern of pits, short grooves, and
naris, character 5(1); (3) the centrum of cervical 3 is longer than ridges does not resemble the fine elongate ridges and grooves
the axis centrum, character 183(1); (4) the presence of a thick- seen in Qianosuchus and other Triassic marine reptiles such as
ened process on the proximal portion of the pubic apron, char- thalattosaurs (Wu et al., 2009) and nothosaurs (Rieppel, 1996),
acter 288(1); and (5) the bone wall thickness to the shaft diame- but is more comparable to that of marine crocodyliforms (espe-
ter of the femur at the midshaft >0.2 but <0.3, character 323(1). cially with respect to the ornamentation of the mandible) such
These five synapomorphies were also identified among the 12 un- as Terminonaris (Wu et al., 2001) and the Tomistominae (Shan
equivocal synapomorphies used by Nesbitt (2011) in his diagnosis et al., 2009). These skull features suggest that Diandongosuchus
of Poposauroidea. Although the interrelationships of Diandon- might have had a lifestyle similar to phytosaurs or recent salt-
gosuchus did not change between the four analyses carried out water crocodiles, living near the water and adapted for an am-
herein, the results derived from the analysis of the total data ma- phibious way of life. In addition, such a way of life for Diandon-
trix (82 taxa and 412 characters) with all multistate characters un- gosuchus may be further inferred from its stomach content that
ordered are preferred in interpreting the phylogeny of the other includes fish remains. However, this assumption can only be ver-
taxa in this study (Fig. 7B; Fig. S1B in Supplementary Data) and ified by a detailed comparative phylogenetic and functional anal-
the synapomorphies of Proterochampsia, Phytosauria, and other ysis of the taxon (Padian, 1987).
major archosaur clades are listed in Appendix 1. It has been documented that the Middle Triassic marine ver-
tebrate fauna of Guizhou and Yunnan, China resembles those
of Europe (Li, 2006; Rieppel et al., 2010). Discovery of the ter-
DISCUSSION
restrial protorosaur Macrocnemus from Yunnan also suggested
Our analysis establishes the poposauroid status of Dian- a close affinity between the semiterrestrial faunas of the east-
dongosuchus and also supports previous studies that proposed ern and western coastal regions along the northern shore of
Qianosuchus as a basal poposauroid (Brusatte et al., 2010; Tethys (Li et al., 2007). This similarity receives no additional
Nesbitt, 2011). It needs to be emphasized, however, that the support from the discovery of Diandongosuchus. Ticinosuchus
poposauroid status of the two Chinese archosaurs obtained in from the Middle Triassic (near to the Anisian–Ladinian bound-
our study is strongly supported by at least 17 synapomorphies, ary) of Monte San Giorgio, Switzerland, is the only archosaur
including five unequivocal character states, for the former taxon found in the Middle Triassic marine vertebrate faunas of Eu-
and more for the latter, although neither bootstrap values nor rope. Nesbitt (2011) stated that the skeletal morphology of
Bremer support values were obtained owing to the difficulty Qianosuchus resembled that of Ticinosuchus. Compared with
of analyzing the large data matrix. Our study hypothesizes that Qianosuchus, Diandongosuchus is morphologically more similar
Diandongosuchus is the basal-most taxon within Poposauroidea, to Ticinosuchus, especially in the postcranial skeleton, sharing
being even more basally positioned than Qianosuchus because it features such as short cervical vertebrae with short ribs, the low
is plesiomorphic in 16 character states, mainly in those: (1) the neural spines of the caudal vertebrae, and the tall dorsal blade
maxilla is excluded from the external naris, character 24(0); (2) of the scapula. Surprisingly, Ticinosuchus and Qianosuchus did
the anterodorsal margin of the maxilla at the base of the dor- not form a sister-taxon relationship, as also suggested by previ-
sal process is convex or straight, character 25(0); (3) the distal ous studies (Li et al., 2006; Brusatte et al., 2010; Nesbitt, 2011).
end of the neural spines in the cervical vertebrae are expanded, Our analysis also failed to recover a sister-taxon relationship
character 191(1); (4) the cervical ribs are short and stout, char- between Diandongosuchus and Ticinosuchus, although they are
acter196(1); and (5) metatarsal IV is longer than metatarsal II, both grouped within Paracrocodylomorpha as separately formed
character 395(0). With the inclusion of Diandongosuchus, the basal-most members of the two subgroups Poposauroidea (the
phylogenetic relationships of Qianosuchus conflict with those re- former) and Loricata (the latter). Therefore, the archosaurs pro-
covered by Dilkes and Sues (2009), Ezcurra et al. (2010), and vide no evidence for a close affinity between the Triassic reptilian
 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1079

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 LI ET AL.—TRIASSIC ARCHOSAUR FROM CHINA 1081

APPENDIX 1. Scores for the new archosaur and the list of synapomorphies for major clades. Character scores for Diandongosuchus added
to the analysis of Nesbitt (2011).

<matrix>
1 2 3 4 5 6
1234567890 1234567890 1234567890 1234567890 1234567890 1234567890
1000150010 0001000000 0000001000 0?00000000 0000000110 1000110000
7 8 9 10 11 12
1234567890 1234567890 1234567890 1234567890 1234567890 1234567890
0010000011 10001000?0 0000?00??? ?????????? ???????000 ??????????
13 14 15 16 17 18
1234567890 1234567890 1234567890 1234567890 1234567890 1234567890
?????????? ???0012110 ?001110??0 0??00010?0 0001?00100 0001?11?0?
19 20 21 22 23 24
1234567890 1234567890 1234567890 1234567890 1234567890 1234567890
0010000000 1000?1?000 0?1000000? ?000100001 10?0?00?00 000000?1??
25 26 27 28 29 30
1234567890 1234567890 1234567890 1234567890 1234567890 1234567890
10001????0 ?????01?01 0????????0 0000000000 0010101100 100000000?
31 32 33 34 35 36
1234567890 1234567890 1234567890 1234567890 1234567890 1234567890
?000?00000 000?100100 001000?00? ?0000000?0 ??1??10000 ?0?00??0??
37 38 39 40 41
1234567890 1234567890 1234567890 1234567890 1234567890 12
?0001??110 1101?221?1 10000?0000 00000?00?2 1110100001 00

List of Synapomorphies for Archosaur Clades (Unequivocal 288∗ (1), 301(0), 323∗ (1), 341(1), and 345(1); “Poposauroidea”
Character States Labeled by an Asterisk) (without Diandongosuchus),12(1), 20(1), 24∗ (1), 25∗ (1), 51(0),
156(1), 181(1), 191∗ (0), 196∗ (0), 200(1), 212(1), 273(2), 319(1),
Proterochampsia, 47∗ (1), 55∗ (1), 75∗ (1), 338∗ (1), 388∗ (1),
349(1), 352(1), and 395∗ (1); Loricata (including Ticinosuchus),
394∗ (1), and 399∗ (2); Phytosauria, 6∗ (6), 10∗ (1), 14∗ (1), 19∗ (1),
2(1), 30∗ (1), 52(1), 108(1), 133(1), 142(1), 191(2), 210∗ (1), 219(1),
27∗ (2), 46∗ (1), 77∗ (1), 139(1), 140(1), 150∗ (1), 160∗ (1), 167∗ (1),
239(1), 270(1), 293∗ (1), 367(1), and 397(1); “Loricata” (with-
210(1), 226∗ (1), 234∗ (0), 305(0), 339∗ (1), 352(1), 378∗ (1), and
out Ticinosuchus), 278∗ (1), 282∗ (1), 339(1), 340∗ (1), 371∗ (2), and
405(1); Archosauria, 32∗ (1), 95(2), 118∗ (1), 122∗ (1), 137∗ (2),
395∗ (1); Rauisuchidae, 14(1) 26(2), 29(1) 35∗ (1), 52(2), 75∗ (3),
220(1), 222(1), 225(1), 237∗ (1), 245∗ (1), 300∗ (1), 320(1), 353(1),
83(1), 125(1), 149(1), 180∗ (1), 191(2), and 249(0); Crocodylomor-
366∗ (1), 377∗ (2), and 398(1); Pseudosuchia, 15(0), 100∗ (1), 117(1),
pha, 2(0), 4(1), 6(2), 11(1), 22(0), 32(2), 37(0), 39(1), 44(1), 55(1),
238∗ (1), 278(1), 282(1), 292(1), 330∗ (1), and 337∗ (1); Suchia,
65(0), 76(1), 79(1), 112(1), 114(1), 115(1), 116(1), 119(1), 120(1),
27∗ (1), 75∗ (2), 114(2), 234(0), 240(1), 320(0), 372∗ (1), 376∗ (2),
124(1), 128(1), 142(0), 156(2), 195(0), 213(2), 223(1), 233(1),
378∗ (1), 403∗ (1), and 410∗ (1); Ornithosuchidae, 8∗ (1), 13∗ (10,
234(1), 269∗ (1), 274(1), 294∗ (0), and 297(2); Avemetatarsalia,
29(1), 33∗ (1), 62∗ (1) 85∗ (1)142∗ (1) 160∗ (1), 190∗ (1), 199∗ (1),
6(1), 44(1), 84(1), 87(1), 93(0), 111(1), 114(1), 141(1), 152(1),
205(1), 210(1), 308∗ (1), 339∗ (1), 340(1), 368∗ (2), and 407(1);
159(0), 179(1), 183(1), 191∗ (0), 197∗ (0), 218(1), 233(1), 255∗ (1),
Paracrocodylomorpha, 51(1), 132(1), 157∗ (1), 195∗ (1), 265(1),
257∗ (1), 274(1), 299∗ (1), 301(0), 232(1), 341(1), 345(1), 347∗ (1),
283(1), 287∗ (1), 291∗ (1), 294∗ (1), 298(1), 314∗ (1), and 411∗ (1);
Poposauroidea (including Diandongosuchus), 1∗ (1), 5∗ (1), 6(5), 348∗ (1), 357∗ (1), 361∗ (1), 363(1), 370(1), 373(1), 374(0), 382∗ (1),
14(1), 90(1), 95(0), 114(0), 141(1), 183∗ (1), 197(0), 202(1), 240(0), 400(0), 401∗ (0), and 412∗ (1).

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