Corresponding author: Taissa Rodrigues (
Academic editor: Hans–Dieter Sues
Over a decade after the last major review of the Cambridge Greensand pterosaurs, their systematics remains one of the most disputed points in pterosaur taxonomy.
The Cretaceous of England is exceptionally rich in pterosaur fossils, which are of historical, morphological, and taxonomic importance. Several deposits contain pterosaur remains, among them the Hastings Group (late Berriasian / Valanginian), Wessex Formation (Barremian), Vectis Formation (Barremian / early Aptian), Gault Clay Formation (Albian), Cambridge Greensand (Cenomanian deposit with reworked fossils thought to be Albian in age) and Chalk Formation (Cenomanian / Turonian) (
Abbreviated taxonomic history of the
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Pioneer works on this fauna, such as by James Scott Bowerbank (1797–1877) and Richard Owen (1804–1892), initially attributed the pterosaurs from the Cretaceous of England in the genus
In 1869, Seeley published an index of specimens from the collection of the Woodwardian Museum (now Sedgwick Museum of Earth Sciences) of the University of Cambridge. This index presented 24 named pterosaur species from the Cretaceous of England, divided in two genera,
It is also possible to interpret these sentences (
List of taxa of the
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In 1874,
List of taxa of the
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The first major review of the
List of taxa of the
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List of taxa of the
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Subsequent authors tended to divide the species of the
List of taxa of the
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Uncertain systematic position |
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List of taxa of the
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As part of the unpublished PhD thesis of the first author, a careful study and revision of the species referred to the
List of taxa of the
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List of taxa of the
List of taxa of the
In this paper, diagnoses are provided for all species and genera considered valid, in addition to photographs and illustrations, which, we hope, will facilitate future discussions about the diversity of pterosaurs in England during the Cretaceous and their relationships with species elsewhere.
Institutional abbreviations: BSP – Bayerische Staatssammlung für Paläontologie und historische Geologie, Munich, Germany; CAMSM – Sedgwick Museum of Earth Sciences, Cambridge, England; IVPP – Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China; MANCH – Manchester Museum, Manchester, England; MN, Museu Nacional / Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; NHMUK – Natural History Museum, London, England; QM – Queensland Museum, Brisbane, Australia; SMNS – Staatliches Museum für Naturkunde, Stuttgart, Germany; SMU, Shuler Museum of Paleontology, Southern Methodist University, Dallas, USA; UERJ – Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil; ZIN – Zoological Institute, Russian Academy of Sciences, St. Petersburg, Russia.
Albian.
Cambridge Greensand, England.
the same as for the type genus.
Seeley erected the name Ornithocheirae in 1870, including only the genus
Albian.
Cambridge Greensand, England.
As for the type species.
CAMSM B54428, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B54552 (
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): tall rostrum*; first pair of premaxillary teeth directed ventrally*; first pair of upper alveoli slightly displaced posteriorly from the anterior margin of the premaxilla*; ventral margin of the palate straight; rostrum not expanded anteriorly.
In the original description and illustration, CAMSM B54428 had a tooth preserved in the first left alveolus (
Aside from the taxonomic and nomenclatural problems surrounding
As detailed above, the taxonomic history of the genus
Albian to Cenomanian / Turonian.
Cambridge Greensand and Chalk Formation, England.
the same as for the type genus.
Derived from the Greek
Albian to Cenomanian / Turonian.
Cambridge Greensand and Chalk Formation, England.
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): comparatively small alveoli (up to 4 mm in diameter) in the anterior portions of the upper and lower jaws; alveoli of the anterior portions of the upper and lower jaws without significant variation in size; alveoli placed in an elevation in relation to the palate and to the dorsal margin of the mandible*; deep palatal ridge; mandibular crest present; spacing between alveoli roughly equivalent to their diameters (modified from
Latter workers did not accept
In the present work,
NHMUK PV 39412, anterior portions of the rostrum and mandible, incomplete scapulocoracoid, proximal ends of the humerus and ulna, and a partial wing phalanx (
Near Maidstone, Burham, Kent, England.
Chalk Formation (Cenomanian / Turonian).
Lonchodraconid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): anterior portion of the premaxillae rounded; anterior portion of the dentaries rounded; divergent alveolar margins of the anterior end of the upper and lower jaws; presence of a premaxillary crest; short, low, blade–like dentary crest*; approximately6 alveoli per 3 cm of jaw margin*.
CAMSM B54855, partial mandibular symphysis (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Lonchodraconid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): deep dentary crest*; ventral margin of the mandible posterior to the dentary crest ascending in lateral view*; ventral depression located posteriorly to the dentary crest*; wide mandibular groove*; approximately 4.5 alveoli per 3 cm of jaw margin.
CAMSM B54855 consists of a fragment of the posterior portion of the mandibular symphysis.
In addition to a deep mandibular groove, CAMSM B54855 shares with
CAMSM B54486, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B 54439 (
Lonchodraconid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): premaxillary crest absent; dorsal margin of the premaxillae rounded; deep palatal ridge*; palate between the elevation of the alveolar margins and the palatal ridge concave; spacing between alveoli larger than their diameters*; approximately 4.5 alveoli per 3 cm of jaw margin.
All pteranodontoids more closely related to
Late Berriasian / Valanginian to Cenomanian.
Hastings Group, England; Wessex Formation, England; Elrhaz Formation, Niger; Jiufotang Formation, China; Khuren–Dukh, Dzun–Bayin Formation, Mongolia; Romualdo Formation, Brazil; Paw Paw Formation, USA; Cambridge Greensand, England; Kem Kem beds, Morocco.
(18.1) Presence of an anterior expansion of the premaxillary tip with the jaw end tall, and (48.1) larger teeth located at the tip of the rostrum (see “Phylogenetic affinities of the species of the
Late Berriasian / Valanginian to Cenomanian.
Hastings Group, England; Wessex Formation, England; Elrhaz Formation, Niger; Jiufotang Formation, China; Khuren–Dukh, Dzun–Bayin Formation, Mongolia; Romualdo Formation, Brazil; Paw Paw Formation, USA; Cambridge Greensand, England; Kem Kem beds, Morocco (
Deposits where anhanguerid fossils have been found.<br/>
Late Berriasian/Valanginian | Hastings Group, England ( |
Barremian | Wessex Formation, England ( |
Aptian | Elrhaz Formation, Niger ( |
Aptian/Albian | Khuren–Dukh, Dzun–Bayin Formation, Mongolia ( |
Albian | Romualdo Formation, Brazil ( |
Cenomanian | Kem Kem beds, Morocco ( |
* this deposit is Cenomanian but the fossils are Albian in age.
Late Berriasian / Valanginian.
Hastings Group, England.
As for the type species.
NHMUK PV R 1822, anterior portion of the rostrum (
St.–Leonards–on–Sea, East Sussex, England.
Hastings Group (late Berriasian / Valanginian).
Anhanguerid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): oval depression beneath the first pair of alveoli*; second, third and fourth pairs of alveoli located laterally*; fifth and sixth pairs of alveoli located more medially than the preceding alveoli on the base of the palatal ridge*; anterior part of the palatal ridge bordered by two shallow longitudinally elongated depressions* (from
The holotype of
CAMSM B 54625, anterior portion of the rostrum (
Chesterton, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Holotype of
Anhanguerid pterosaur with the following combination of characters that distinguishes it from other members of the clade: anteriorly located and tall premaxillary crest; anterior margin of the premaxillary crest concave in lateral view; first pair of upper teeth positioned on the anterior margin of the rostrum.
A second specimen referable to this species is the holotype of
Here, we recognize that
After the Brazilian paleontologist Diogenes de Almeida Campos, who made valuable contributions to the knowledge of pterosaur diversity in Brazil and was a major influence to us, and
Albian.
Cambridge Greensand, England.
Pterodactyloid pterosaurs with the following combination of characters that distinguishes it from other members of the clade: anterior tip of the premaxillae and maxillae round in lateral view; premaxillary crest absent; anterior expansion of the rostrum present; palate curving dorsally; first pair of alveoli located anteriorly.
CAMSM B 54556, anterior portion of the rostrum (
Haslingfield, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): dorsal margin of the rostrum straight to gently concave in lateral view; palatal ridge extends anteriorly until just posterior to the second pair of alveoli; spacing between alveoli irregular, with the anterior alveoli closer and the posterior ones more distant from each other; density of almost 3 alveoli each 3 cm anteriorly and 2,5 alveoli each 3 cm posteriorly*; tip of the rostrum dorsoventrally flattened, wider than high in anterior view*; second and third alveoli face lateroventrally; anterior portion of the premaxillae slightly expanded.
CAMSM B54422, anterior part of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): tall rostrum; anterior expansion of the rostrum ends abruptly behind the third pair of alveoli*; palatal ridge extending posteriorly to the level of the third pair of alveoli; third pair of alveoli much larger than fourth*.
The third alveoli have different sizes on the left and right sides; this could be explained on taphonomic grounds (e.g.,
It is noteworthy that the drawing of CAMSM B54422 was reversed in
CAMSM B54431 (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): developed anterior expansion, lacking a marked constriction; presence of a depression above the first pair of alveoli; anterior depression faces anteroventrally*; second and third alveoli very large in size; fourth pair of alveoli much smaller than the second and third.
The syntypes, CAMSM B54431 (the more complete one) and CAMSM B54432, both are anterior portions of upper jaws. They are quite incomplete and abraded, but they are identical where comparable and demonstrate that their features are valid morphological characters rather than taphonomic artifacts.
This lunate area is a depression above the first pair of alveoli; a depression in the same location is also present in
From the Greek
Cenomanian / Turonian.
Chalk Formation, England.
As for the type–species.
NHMUK PV 39409, anterior portion of the rostrum (
Burham, Kent, England.
Chalk Formation (Cenomanian / Turonian).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): premaxillary crest present; premaxillary crest begins posteriorly (at the seventh pair of alveoli) but before the nasoantorbital fenestra*; palatal ridge extending anteriorly up to the third pair of alveoli; second and third alveoli similar in size and larger than the fourth; spacing between alveoli irregular, with the anterior alveoli more closely spaced and the posterior ones more widely separated from each other; almost 3 alveoli per 3 cm of jaw margin anteriorly and 2 alveoli each 3 cm posteriorly*; anterior expansion absent; palate dorsally curved.
NHMUK PV 39409 was originally reported as having a tooth preserved in the first right alveolus. During examination of the holotype in 2007 and 2009, the tooth was no longer preserved with the holotype and could not be found.
CAMSM B54440, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): premaxillary crest absent; anterior expansion absent; palate dorsally curved; moderately developed palatal ridge; palate between the elevated alveolar rims and the palatal ridge concave; palatal ridge extending anteriorly up to the second pair of alveoli; alveoli ventrolaterally oriented; spacing between alveoli less than their diameters; approximately 5.5 alveoli per 3 cm of jaw margin*.
It is suggested here that
CAMSM B54835, anterior portion of the rostrum (
Horningsea, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): alveoli small (about 4 to 5 mm in diameter); dorsal margin of the rostrum forms an angle of 27° with the ventral margin*.
NHMUK PV 43074, partial mandibular symphysis (
Folkestone, Kent, England.
Gault Clay Formation (Albian).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade (autapomorphies are marked with an asterisk): anterior expansion absent; mandibular crest absent; mandibular groove about 2.5 cm wide; mandibular groove with elevated margins; mandibular groove extends until the second pair of alveoli; alveoli of the anterior portion of the mandible without significant variation in size; alveoli equally spaced; first pair of teeth face anterodorsally; transverse section ‘V–shaped’; approximately 4 alveoli per 3 cm of jaw margin*.
It shares with
Anterior portion of the rostrum (?CAMSM B 54794) (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Pterodactyloid pterosaur with the following combination of characters that distinguishes it from other members of the clade: anterior expansion absent; palate dorsally curved; moderate palatal ridge; palatal ridge extending anteriorly up to the third pair of alveoli; spacing between alveoli approximately equal to their diameters; approximately 4.5 alveoli per 3 cm of jaw margin.
In the original description,
Collection data provided by the curators at the Sedgwick Museum of Earth Sciences in Cambridge list the specimen CAMSM B 54794 as the holotype of
In the lack of more complete material, we here refrain from naming a new genus based on the present specimen, and refer to it using the binomen in which it was originally proposed.
NHMUK PV 2353 and 2353a, partial left humerus.
Cuckfield, Sussex, England.
Upper Tunbridge Wells Sand Formation (
This species was first described as a bird (
NHMUK PV 39418, distal end of a wing metacarpal.
Chesterton, Cambridgeshire, England.
Chalk Formation (Cenomanian / Turonian).
The two known pterosaur clades from the Chalk Formation are the
NHMUK PV 39410, partial rostrum and mandible (
Burham, Kent, England.
Chalk Formation (Cenomanian / Turonian).
The holotype of
The lectotype of
To further complicate the taxonomy of this species,
CAMSM B54423, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B54423 is a fragment of the anterior portion of the premaxillae and maxillae, lacking the anteriormost end. It is likely that the first pair of alveoli is not preserved (
CAMSM B 54433a, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
The holotype of
CAMSM B54443, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B 54437, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B 54499, anterior portion of a jaw (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
Description: CAMSM B 54499 is a very fragmentary specimen, in which much of the left side, especially the oral surface, was not preserved.
The taxonomy of this species is controversial. It was placed in the genus
CAMSM B 54544, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B 54444, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B 54444 is a fragment of the anterior portion of the premaxillae and maxillae, including three pairs of alveoli. The first pair of alveoli is located anteriorly, separated by a thin wall of bone from the second pair. The spacing between the second and third pairs is larger but still smaller than the diameter of the alveoli. Such spacing is common within species of the
CAMSM B54644, anterior fragment of an ?upper jaw (
Ditton, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B54644 was tentatively identified by
CAMSM B 54612, anterior fragment of an upper jaw (
Smithswashing, Coton, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B 54441, anterior portion of the rostrum (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
CAMSM B 54584, anterior portion of the rostrum (
Coton, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
anterior portion of the rostrum (collection data could not be recovered) (
Cambridge, Cambridgeshire, England.
Cambridge Greensand (Cenomanian; fossils Albian in age).
The holotype of
The species was based on a fragmentary mandible, lacking the tip. It did not have a dentary crest (
NHMUK PV R 1823, partial mandibular rami (
St.–Leonards–on–Sea, Sussex. England.
Hastings Group, Wealden (late Berriasian / Valanginian).
The holotype of
As explained above, in 1869 Seeley created several names for pterosaur taxa from the Cretaceous of England, but these nomenclatural acts were disclaimed and, therefore, intentionally unavailable.
With the genus
Another occurrence of the
ZIN PNT–S50–1, a partial mandibular symphysis from the Cenomanian of Lysaya Gora Hill, Saratov district, in the southern European part of Russia, has been referred either as
Additional remains from the territories of the former Soviet Union referred as ornithocheirids come from different localities in Russia and in Uzbekistan and include cranial and postcranial elements and isolated teeth. These records include a partial tip of the rostrum (specimen ZIN PH no. 50/44), referred as
QM F10613, a mandibular symphysis from Albian Toolebuc Formation of Australia, has been referred to aff.
Lastly, the species of the
Comparison between
The phylogenetic position of the species of the
The phylogenetic studies of
The cladistic matrix of
In addition, the strict consensus tree from this reanalysis shows some differences in relation to the one published by
Strict consensus tree of the reanalysis of the matrix by
Identical topology to the one found in the strict consensus tree of the reanalysis using PAUP* was recovered analyzing the same matrix in TNT (
It is interesting to note that the analyses of
The analyses of
A second dispute involves the use of postcranial material in the analyses of
The cervical vertebrae that
Therefore, reanalyses using the humeri and cervical vertebrae as separate OTUs were undertaken, using the data matrices of
Strict consensus tree of the reanalysis of the matrix by
Strict consensus tree of the reanalysis of the matrix by
In the case of the matrix by
Strict consensus tree of the reanalysis of the matrix by
In order to access the phylogenetic relationships of the species of the
The run with all OTUs (with a total of 81 taxa, three of them outgroups, all characters treated as unordered) resulted in 30 most parsimonious trees with a length of 246 steps each. Several nodes were collapsed in the strict consensus tree, including some non–pterodactyloid taxa (as noted by
Strict consensus tree of the analysis including the species of the
The low resolution of the consensus tree is likely due to only a few taxa whose position changes greatly between different input trees (e.g.,
The agreement subtree of our analysis had only 46 taxa of the original 81 and presented a monophyletic
Agreement subtree of the analysis including the species of the
A new analysis was undertaken and, in comparison to the agreement subtree, five additional species were not pruned from the analysis:
Agreement subtree of the analysis including the species of the
Agreement subtree of the analysis including the species of the
The agreement subtree plus
Agreement subtree of the analysis including the species of the
Agreement subtree of the analysis including the species of the
The species of the
One would expect that, having so many species based on fragmentary material, several would prove to be non–diagnosable. However,
Some species regarded by
Another major difference between the present work and the review done by
The pterosaur assemblage from the Cretaceous of England possesses a high diversity. One reviewer pointed out that this may be an artifact caused by lack of knowledge of intraspecific variation. This may well be true, but, as previously noted (e.g.,
The Cambridge Greensand is a remanié deposit (
Analysis of the phylogenetic relationships of these species, especially with the ones from the more or less coeval Romualdo and Crato formations of the Santana Group in Brazil, proved to be challenging, as expected. Using a modified version of the matrix by
We would like to acknowledge the editor, Hans–Dieter Sues, and Darren Naish and Alexander Averianov for their thorough review and constructive criticism. Thanks also to Juliana Sayão, Leonardo Avilla, Marcelo Britto and Ulisses Caramaschi for their valuable comments on the original version, Brian Andres for sharing his pterosaur bibliography, Richard Butler for discussion on pruning, Lorna Steel for photographs, information, and permission to photograph the specimens at the NHMUK, André Veldmeijer for photographs of
Character list (modified from Wang et al. 2009).
0 – straight or curved downward; 1 – concave; 2 – only rostrum curved upward
0 – laterally compressed; 1 – comparatively broad
0 – reduced; 1 – elongated
0 – absent; 1 – present
0 – absent; 1 – present
0 – above the premaxillary tooth row; 1 – displaced posterior to the premaxillary tooth row
0 – broad; 1 – narrow
0 – absent; 1 – present
0 – naris smaller than antorbital fenestra; 1 – naris larger than antorbital fenestra; 2 – both very reduced (slit–like)
0 – separated; 1 – confluent, shorter than 45% of the skull length; 2 – confluent, longer than 45% of the skull length
0 – eliptical or ovoid; 1 – triangular, with base and height subequal; 2 – triangular with height larger than base; 3 – very elongated anteroposteriorly
0 – absent; 1 – present
0 – absent; 1 – present
0 – same level or higher; 1 – orbit lower than the dorsal rim of the nasoantorbital fenestra
0 – absent; 1 – present
0 – absent; 1 – confined to the anterior portion of the skull, beginning near or at the tip of the rostrum; 2 – starting anterior to the anterior margin of the nasoantorbital fenestra, not reaching the skull roof above the orbit; 3 – starting anterior to the anterior margin of the nasoantorbital fenestra, extending beyond occipital region; 4 – starting at about the anterior margin of the nasoantorbital fenestra, reaching the skull roof above the orbit but not extending over the occipital region; 5 – starting close or at the anterior portion of the skull and extended over the occipital region; 6 – starting close or at the anterior portion of the skull, reaching orbit but not extended over the occipital region; 7 – starting at the posterior half of the nasoantorbital fenestra; 8 – located at the anterior portion of the skull, beginning more posteriorly but before the anterior margin of the nasoantorbital fenestra.
0 – striated, low with a nearly straight dorsal margin; 1 – striated, high with a nearly straight dorsal margin; 2 – striated, high, spike–like; 3 – round dorsal margin, bladeshaped; 4 – smooth, moderately expanded anteriorly and forming a low rod–like extension posteriorly; 5 – smooth, very expanded anteriorly and forming a low rod–like extension posteriorly; 6 – smooth, starting low anteriorly and very expanded posteriorly; 7 – smooth, with a straight anterior margin, forming a triangular lateral outline
0 – absent; 1 – present, with jaw end high; 2 – present, with the jaw end dorsoventrally flattened
0 – absent; 1 – present
0 – broad; 1 – narrow; 2 – absent
0 – absent; 1 – placed laterally, long, straight, and directed ventrally (not fused with maxillae); 2 – placed laterally, reduced; 3 – placed medially, long; 4 – placed medially, reduced; 5 – placed laterally, short and directed anteriorly
0 – absent; 1 – present
0 – absent; 1 – present
0 – broad; 1 – thin, subvertical; 2 – thin, strongly inclined posteriorly
0 – absent; 1 – low and blunt; 2 – low and elongated; 3 – high and expanded posteriorly
0 – absent; 1 – present, blunt; 2 – present, laterally compressed and posteriorly expanded, with a rounded posterior margin; 3 – present, constituting the base of the posterior portion of the cranial crest
0 – absent; 1 – present
0 – vertical or subvertical; 1 – inclined about 120° backwards; 2 – inclined about 150°backwards
0 – under the posterior half of the orbit or further backwards; 1 – under the middle part of the orbit; 2 – under the anterior half of the orbit
0 – absent; 1 – present
0 – does not extend backwards; 1 – extends backwards
0 – absent; 1 – present
0 – absent; 1 – present
0 – short; 1 – elongated
0 – absent; 1 – present
0 – discrete, tapering anteriorly; 1 – strong, tapering anteriorly; 2 – strong, confined to the posterior portion of the palate
0 – absent; 1 – present
0 – absent or very reduced; 1 – present and larger than subtemporal fenestra; 2 – present but smaller than subtemporal fenestra
0 – absent; 1 – present
0 – absent or very short; 1 – present, at least 30% of mandible length
0 – absent; 1 – present, with jaw end high; 2 – present, with the jaw end dorsoventrally flattened
0 – absent; 1 – present
0 – absent; 1 – present
0 – absent; 1 – present
0 –blade–like and short, placed anteriorly; 1 – massive and deep
0 – absent; 1 – present
0 – teeth present, evenly distributed along the jaws; 1 – teeth absent from the anterior portion of the jaws; 2 – teeth confined to the anterior part of the jaws; 3 – jaws toothless
0 – all teeth roughly the same size; 1 – larger teeth located at the tip of the rostrum; 2 – larger teeth located posteriorly
0 – absent; 1 – present
0 – absent; 1 – present
0 – absent; 1 – present
0 – present; 1 – absent
0 – absent; 1 – present, 15 or less on each side of the upper jaws; 2 – present, more than 15 on each side of the upper jaws
0 – absent or less than 150; 1 – present, more than 150
0 – absent; 1 – present
0 – absent; 1 – present
0 – absent; 1 – present
0 – unfused; 1 – fused
0 – absent; 1 – present
0 – absent; 1 – present
0 – short, sub–equal in length; 1 – elongated; 2 – extremely elongated
0 – present; 1 – absent
0 – tall, blade–like; 1 – tall, spike–like; 2 – low, blade–like; 3 – extremely reduced or absent
0 – more than 15; 1 – 15 or less
0 – absent; 1 – present
0 – subequal or longer than coracoid; 1 – scapula shorter than coracoid (1 > sca/cor > 0.80); 2 – substantially shorter than coracoid (sca/cor ≤ 0.80)
0 – elongated; 1 – sub–oval
0 – elongated; 1 – stout, with constructed shaft
0 – no developed articulation surface; 1 – articulation surface flattened, lacking posterior expansion; 2 – articulation surface oval, with posterior expansion
0 – absent; 1 – present
0 – absent; 1 – present
0 – absent; 1 – shallow and elongated; 2 – deep and short
0 – hu/mcIV > 2.50; 1 – 1.50 < hu/mcIV < 2.50; 2 – 0.40 < hu/mcIV < 1.50; 3 – hu/mcIV < 0.40
0 – hu/fe ≤ 0.80; 1 – 1.4 > hu/fe > 0.80; 2 – hu/fe > 1.40
0 – humerus plus ulna about 0.80% or less of femur plus tibia length (hu+ul/fe+ti ≤ 0.80); 1 – humerus plus ulna larger than 0.80% of femur plus tibia length (hu+ul/fe+ti > 0.80)
0 – absent; 1 – present
0 – absent; 1 – present
0 – reduced, positioned close to the humerus shaft; 1 – enlarged, proximally placed, with almost straight proximal margin; 2 – subrectangular, extending down the humerus shaft for at least 30% of humerus length; 3 – distally expanded; 4 – enlarged, hatchet shaped, proximally placed; 5 – enlarged, hatched shaped, positioned further down the humerus shaft; 6 – enlarged, warped; 7 – long, proximally placed, curving ventrally
0 – absent or reduced; 1 – present, directed posteriorly; 2 – present, massive, with a developed proximal ridge
0 – oval or D–shaped; 1 – subtriangular
0 – ulna 3.6 times longer than metacarpal IV (ul/mcIV > 3.6); 1 – length of ulna between 3.6 and two times the length of metacarpal IV (3.6 > ul/mcIV > 2); 2 – ulna less than two times the length of metacarpal IV (ul/mcIV < 2)
0 – subequal; 1 – diameter of the radius about half that of the ulna; 2 – diameter of the radius less than half that of the ulna
0 – unfused; 1 – fused in a rectangular unit; 2 – fused in a triangular unit
0 – absent; 1 – shorter than half the length of the ulna; 2 – longer that half the length of the ulna
0 – articulating with carpus; 1 – metacarpal III articulates with carpus, metacarpals I and II reduced; 2 – not articulating with carpus
0 – both small and reduced; 1 – both enlarged with ph1d4 over four times the length of mcIV (ph1d4/mcIV> 4.0); 2 – both enlarged with ph1d4 between two and four times the length of mcIV (4.0 > ph1d4/mcIV≥ 2.0); 3 – both enlarged with ph1d4 less than two times the length of mcIV (ph1d4/mcIV< 2.0)
0 – ph1d4 reduced; 1 – ph1d4 elongated and less than twice the length of ti (ph1d4/ti smaller than 2.00); 2 – ph1d4 elongated about or longer than twice the length of ti (ph1d4/ti subequal/larger than 2.00)
0 – both short or absent; 1 – elongated with second phalanx about the same size or longer than first (ph2d4/ph1d4 larger than 1.00); 2 – elongated with second phalanx up to 30% shorter than first (ph2d4/ph1d4 between 0.70 – 1.00); 3 – elongated with second phalanx more than 30% shorter than first (ph2d4/ph1d4 smaller than 0.70)
0 – both short or absent; 1 – ph3d4 about the same length or larger than ph1d4; 2 – ph3d4 shorter than ph1d4
0 – both short or absent; 1 – ph3d4 about the same size or longer than ph2d4; 2 – ph3d4 shorter than ph2d4
0 – femur about twice or longer than metacarpal IV (fe/ mcIV ≥ 2.00); 1 – femur longer but less than twice the length of metacarpal IV (1.00 < fe/mcIV < 2.00); 2 – femur about the same length or shorter than metacarpal IV (fe/mcIV ≤ 1.00)
0 – more than 30% of tibia length; 1 – less than 30% of tibia length
0 – with four phalanges; 1 – with 2 phalanges; 2 – with 1 or no phalanx (extremely reduced)
0 – reduced or absent; 1 – elongated, straight; 2 – elongated, curved; 3 – elongated, very curved (boomerang shape)
Data matrix (modified from Wang et al. 2009).
0000000000 000000–000 0–00000000 00000–0000 0000–00000 0000000000 0000000000 0000000000 0000000000 0000
000?00?000 00?000–000 0–0?00000? ????????0? 00?0–000?0 0?00?00??? 00?00????? ???00??0?? ?0?0?????? ????
0000000000 000000–000 0–00000000 00000–0000 0000–00000 0000000000 0000000000 0000000000 0000000000 0020
010000100? ??0??0–00? 0–?00????? ????????00 0000–00000 0110000??? 0??10????? ??011??100 00?1011??? 001?
01000010?? ?????0–00? ????00??0? ????????0? 0000–00000 0110000??? 01?1000010 0?021??1?? 00?1011222 1011
010000100? ?????0–00? 0–??0????? ????????0? 0000–00000 0110000??? 00?100?010 0?021??1?? 00?1011222 00??
?10000100? ?????0–00? 0–??0????? ??????0?00 0000–00000 011000??0? 0?0???001? ???21??10? ?????????? ????
001??10000 000000–?00 0–00000000 00000–10?? ??????00?? ?????????? ?????????? ?????????? ?????????? ????
0010010000 000000–000 0–0000010? 0?0?????00 0100–00000 1100000?00 00?0?00010 0?11?00200 11?10????? 1???
?????????? ?????????? ????00???? ?000?????? ?????0???0 11??000??? ?????????? ??111????? 1???021211 101?
?01??1??00 ????????0? ?????????? ?????????0 ??????0000 1100000?00 0????0???0 0?1110???? 1????21111 00??
?0???????? ?????????? ?????????? ?????????? ?????000?0 1100000??? ???010001? ??111??100 11?1021111 0011
0010010010 200000–001 0–0000000? 0?0?????00 0000–00000 0100000?00 0000100010 ??11100100 1111021111 1011
0010010??? ???????00? ??0????1?? ????????00 0000–00000 0120000??0 10201000?0 ??111?01?? 10?1021111 1013
0010010010 000000–000 0–00000100 0?0????101 0010–00000 0100000??? 0000100010 ??11100300 10?1021111 1013
0010010000 000000–000 0–00000100 0?000–010? 0000–00000 0100000?00 0000100010 0111100100 10?1021111 0013
00100100?0 ?0?000–00? 0–??000?0? ?????????0 0000–?0?00 ??00000??? 0??0?????? ??111??1?? 10?1021111 00??
0010010000 ?00000–00? 0–?000010? 0?0?????00 0000–00000 01?0000?0? 0000100010 0?011??100 00?1021111 0013
0010010010 0000061000 0–000?000? ?????????? ??????0000 000000???? 00?00????0 ?????????? ?0???????1 ????
0010010100 3000020101 ??00????0? ????????00 ??????0000 01000????? ?????????? ?????????? ?????????? ????
00100101?0 ?????2?0?? ?????????? ????0–1??? ??????0??? ?????????? ?????????? ?????????? ?????????? ????
0010010010 100000–000 0–1000010? 0???????00 0100–00000 0100000000 0000100010 0?1???12?? 11?1012122 0010
0010010010 100000–000 0–10000100 0?000–1100 0100–00000 0100000000 0000100010 0111100200 11?1012122 1010
?0???????? ?????????? ?????????? ????????10 ?000–100?0 110000???? ?????????? ?????????? ?????????? ????
0010010000 0000022000 0–00??010? ????????10 0001110000 1100000??? 00???????? ???21??20? ??????1211 ?0??
0010010020 000000–000 0–00000110 0?000–??01 0010–00000 010000000? 0000100010 0111100400 11?1022222 1012
0010010020 000000–000 0–00000110 00000–1101 0010–00000 0100000000 0000100010 0111100400 11?1012222 1012
00100100–1 –00000–002 100000121? 0?0?0–??01 0000–00000 0120000000 1121000010 0121100700 21?1031222 2020
00100100–1 –00000–002 100000121? 0?0?0–??01 0000–00000 0120000000 1121000010 0121100700 21?2031222 2020
00100100–1 –000040002 100000121? 0???????0? 0000–00000 0120000??? 11??0?001? ??211??7?0 21???31??? 2???
00100100–1 –000040002 100000121? 0?0?????01 0000–00000 0120000??? 11???00010 0?211??7?0 21???31222 21??
00100100–1 –000020202 500000121? 0?0???0201 2000–00100 010000???? ?????????? ?????????? ?????????? ????
10100100–1 –00000–002 100000121? 0?0?????01 0000–00000 010100???0 11210?001? ??211??7?0 2?1??31222 2020
10100100–1 –0?000–002 0–0?00121? 0?0?????01 0000–00000 010100??00 112?0?001? ??211??7?? 21???312?? 2020
10100100–1 –000010002 10000212?0 0?0?0–??0? 0000–02000 010000???? ?????????? ?????????? ?????????? ????
10100100–1 –00000–002 200002121? ??0?0–??01 0000–02000 010000?00? 112??0001? ??210??700 21??031222 21??
10100100–1 –0?000–002 20??02??1? ??0?????0? 0?00–02000 010000???? ?????0001? ?????????? ??????1222 ?1??
00100100–1 –00000–002 0–00000?1? 0?0?????01 0000–03–00 0100001?1? 010?0????? ??31???50? ????232222 2???
00100100–1 –00000–002 0–00000?11 0?010–1201 0000–03–00 0100001110 0101000010 013111050? 2122232222 20??
00100100–1 –00000–002 6001000?2? ????????01 0000–03–00 0100000??0 01?10000?0 ???11?17?? 2????31?22 2120
?0???????? ?????????? ?????????? ????1???01 0000–?00?0 ???000???? ?????????? ?????????? ?????????? ????
?010110??? ?????0–0?? ?????????? ????10???? ??????00?0 ???000???? ?????????? ?????????? ?????????? ????
?010110??? ?????0–0?? ?????????? ????10???? ??????0000 ???000???? ?????????? ?????????? ?????????? ????
?0???????? ?????????? ?????????? ????1???01 0000–?0000 ???000???? ?????????? ?????????? ?????????? ????
?010?10??? ?????170?? ?????????? ????10???? ??????0??0 ???000???? ?????????? ?????????? ?????????? ????
?010010??? ?????0–0?? ?????????? ????10???? ??????0000 ?100?0???? ?????????? ?????????? ?????????? ????
?010110??? ?????830?? ?????????? ????10???? ??????0000 01?000???? ?????????? ?????????? ?????????? ????
10100100–1 –00000–002 4000330121 01010–1201 0000–03–00 0100001111 0111011010 0121110611 2122232222 2020
00101100–2 –00000–002 ??02???12? ????????0? 0000–02000 01001010?? 011??1?1?0 ?22110?61? 222?1312?? 21??
00101100–2 –?0??0–0?2 0–?2?????0 ????0–???1 0000–?2000 0100101?1? 0????11110 02?1???611 ?2?????1?? ????
?????????? ?????????? ?????????? ?????????? ?????????1 0?00?0??11 010??????? ??20001720 211??312?? 2120
00100100–1 –100131012 0–0023012? 1?1?????01 0000–01–01 010000???? ?????????? ?????????? ??1??????? ????
20100100–1 –100131012 0–00230121 1111101201 0000–01–01 0100001111 0101000010 ?2200??7?0 211?131222 2120
001??10??? ?????0–?0? ?????????? ????11???? ??????0000 ???001???? ?????????? ?????????? ?????????? ????
?0???????? ?????????? ?????????? ????1???01 ???11?00?0 ???001???? ?????????? ?????????? ?????????? ????
?010010??? ?????170?? ?????????? ????11??01 00010?0000 010001???? ?????????? ?????????? ?????????? ????
00100100–1 –00100–002 0–000?012? 1???????0? 0000–03–00 01000011?? 213?0000?1 0?200??7?? 21?2?313?? 2???
?????????? ?????????? ?????????? ?????????? ??????3–00 0100001110 213??????? ?????107?0 ?????????? ????
00100100–1 –00107?002 0–00???121 ????0–1?01 0000–03–00 0100001110 213?000011 0?20010720 211??31322 2?20
00110100–2 –011055002 ??0123012? 1????????1 ?001103–00 010000???? ?????????? ?????????? ?????????? ????
00110100–2 –011055002 ??01230120 11110–1201 0001103–00 0100000?11 010?000010 1?20011720 2112?31??? 2120
00100100–2 –011056002 4001230121 1111121201 0000–03–00 010000???? ?????????? ?????????? ?????????? ????
00100100–2 –011056002 ??01230121 1111121201 0000–03–00 0100001111 010??00010 1220010720 211??313?? 2???
10101100–? ?????0–102 ?????????? ????101??? ??????0100 010000???? ?????????? ?????????? ?????????? ????
?01011???? ?????0–1?? ?????????? ????10???? ??????01?0 ???000???? ?????????? ?????????? ?????????? ????
?01011???? ?????0–1?? ?????????? ????10???? ??????0100 ???000???? ?????????? ?????????? ?????????? ????
0010110??? ?????0–10? ?????????? ????10???? ??????0100 ???000???? ?????????? ?????????? ?????????? ????
?0???????? ?????????? ?????????? ????1???01 1000–?01?0 0??000???? ?????????? ?????????? ?????????? ????
10101100–1 –00000–?02 3100330121 ????101?01 ?000–00100 010000???? ?????????? ?????????? ?????????? ????
00101100–1 –00001?102 ??00???121 ????101??1 1000–001?0 010000???? ?????????? ?????????? ?????????? ????
?0101100–? –????13102 ????33???? ????101??? ??????0100 010000???? ?????????? ?????????? ?????????? ????
?010110??? ?????1?1?? ?????????? ?????????? ??????01?0 010000???? ?????????? ?????????? ?????????? ????
?010110??? ?????1?1?? ?????????? ????10???? ??????01?0 ??00?0???? ?????????? ?????????? ?????????? ????
?0101100–? –000013102 ??00??0121 ????????01 ?0010001?0 010000??11 01???????? ?????????? ?????????? ????
00101100–1 –000013102 ??00110121 0101101201 ?????00110 0?0000???? ?????????? ?????01611 ?20??????? ????
00101100–1 –000013102 ?–00110121 0101101201 1001000110 0100001?11 ?????21120 02?1101611 ?2???????? ????
?0???????? ?????????? ?????????1 ????1???01 10010001?0 010000???? ?????????? ?????????? ?????????? ????
00101100–1 –000013102 3100110121 0101??1201 1001000110 0100000111 0111021120 0221101611 222?1????? 2120
00101100–1 –000013102 ??00110121 0101101201 1001000110 010000???? ?????????? ?????????? ?????????? ????
00101100–1 –00001?102 3100110121 0101101201 ?00??00110 0100000111 0111?21120 0????01611 ?22?1????? ????
00101100–1 –000013102 ??00110121 0101111201 1001000100 010000???? ?????????? ?????????? ?????????? ????