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An avian vertebra from the continental Cretaceous of Morocco, Africa

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5 ABSTRACT: We report the occurrence of an isolated avian dorsal vertebra in Cretaceous strata of Morocco. The specimen was found near Erfoud oasis in the Tafilalt region of southeastern Morocco preserved in a reddish sandstone. It has a large neural canal (ratio height neural canal/cranial articulation surface = 0.67), a feature regarded as a synapomorphy of Aves. Compared to dorsal vertebrae of other Mesozoic birds, the Moroccan specimen is most similar to Rahona ostromi from the Late Cretaceous of Madagascar. The absence of a developed pleurocoel, however, indicates that it belongs to a distinct taxon. Although the correct phylogenetic position of this specimen within Aves cannot be reliably determined, it most likely represents a basal group. This specimen is significant because it represents the second osteological evidence of a Cretaceous bird from northern Gondwana.
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1 Submitted on July 7, 2003. Accepted on January 29, 2004.
2 Museu Nacional/UFRJ, Programa de Pós-Graduação em Ciências Biológicas/Zoologia. Quinta da Boa Vista, São Cristóvão, 20940-040, Rio de Janeiro, RJ,
Brasil. E-mail: driff@mn.ufrj.br.
Fellow of Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).
3 Long Island Natural History Museum. P.O. Box 262, Levittown, NY 11756. E-mail: bjmader@email.msn.com.
4 Museu Nacional/UFRJ, Departamento de Geologia e Paleontologia. Quinta da Boa Vista, São Cristóvão, 20940-040, Rio de Janeiro, RJ, Brasil. E-mail:
kellner@mn.ufrj.br.
Fellow of Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Academia Brasileira de Ciências.
Associate Researcher, American Museum of Natural History, New York.
5 North Carolina State University, Department of Marine, Earth and Atmosp. Science. Raleigh, NC 27695-8208. E-mail: dale_russell@ncsu.edu.
Arquivos do Museu Nacional, Rio de Janeiro, v.62, n.2, p.217-223, abr./jun.2004
ISSN 0365-4508
AN AVIAN VERTEBRA FROM THE CONTINENTAL CRETACEOUS
OF MOROCCO, AFRICA1
(With 7 figures)
DOUGLAS RIFF 2
BRYN MADER 3
ALEXANDER WILHELM ARMIN KELLNER 4
DALE RUSSELL 5
ABSTRACT: We report the occurrence of an isolated avian dorsal vertebra in Cretaceous strata of Morocco.
The specimen was found near Erfoud oasis in the Tafilalt region of southeastern Morocco preserved in a
reddish sandstone. It has a large neural canal (ratio height neural canal/cranial articulation surface = 0.67),
a feature regarded as a synapomorphy of Aves. Compared to dorsal vertebrae of other Mesozoic birds, the
Moroccan specimen is most similar to Rahona ostromi from the Late Cretaceous of Madagascar. The absence
of a developed pleurocoel, however, indicates that it belongs to a distinct taxon. Although the correct
phylogenetic position of this specimen within Aves cannot be reliably determined, it most likely represents a
basal group. This specimen is significant because it represents the second osteological evidence of a Cretaceous
bird from northern Gondwana.
Key words: fossil bird, Late Cretaceous, Morocco, Africa.
RESUMO: Uma vértebra aviana do cretáceo continental do Marrocos, África.
Registra-se a ocorrência de uma vértebra dorsal aviana isolada proveniente dos estratos cretácicos do Marrocos.
O espécime foi encontrado próximo ao oásis Erfoud na região de Tafilalt no sudoeste do Marrocos, preservado
num arenito avermelhado. Possui um amplo canal neural (proporção altura do canal neural/altura da
superfície articular cranial = 0.67), uma característica considerada sinapomórfica de Aves. Comparado com
vértebras dorsais de outras aves mesozóicas, o espécime marroquino é muito similar à Rahona ostromi do
Cretáceo Superior de Madagascar. A ausência de um pleurocelo desenvolvido, entretanto, indica que pertença
a um táxon distinto. Embora uma correta posição filogenética desse espécime dentro de Aves não possa ser
seguramente determinada, ele provavelmente representa um grupo basal. Esse espécime é significante por
representar o segundo registro osteológico de uma ave cretácica do norte do Gondwana.
Palavras-chave: ave fóssil, Cretáceo Superior, Marrocos, África.
INTRODUCTION
The record of Mesozoic birds in Gondwana is quite
poor and most of the osteological material is
restricted to South America. Skeletal material has
been reported from Patagonia, Argentina (CHIAPPE
& CALVO, 1994), and fossil feathers have been found
in the Santana Formation, Brazil (MARTINS NETO
& KELLNER, 1988; KELLNER & CAMPOS, 2000). A
few osteological remains are known from other parts
of Gondwana, including a tibiotarsus from the Early
Cretaceous of Australia attributed to the
Enantiornithes (MOLNAR, 1986), appendicular
elements of Anseriformes from the Late Cretaceous
of Antarctica (NORIEGA & TAMBUSSI, 1995), and
skeletal remains of the Enantiornithes from the Late
Cretaceous of Lebanon (DALLA VECCHIA &
CHIAPPE, 2003). In current Africa, the avian record
is limited to footprints (Ellenberg, 1974 and Lockey
et al., 1992 apud CHIAPPE, 1995) and incomplete
limb elements and one partial skeleton from
Madagascar (FORSTER et al., 1996; 1998). Here we
report the occurrence of an isolated dorsal vertebra
(briefly mentioned before - RIFF et al., 2002) from
Albo-Cenomanian sandstones of the Kem Kem,
found near Erfoud oasis in the Tafilalt region of
southeastern Morocco (RUSSELL, 1996), housed in
the Canadian Museum of Nature (CMN 50852; cast
218 D.RIFF, B.MADER, A.W.A.KELLNER & D.RUSSELL
Arq. Mus. Nac., Rio de Janeiro, v.62, n.2, p.217-223, abr./jun.2004
MN 6920-V at the Museu Nacional; Fig.1). The
specimen was preserved in a reddish sandstone,
deposited under fluvial condition (RUSSELL, 1996),
and was prepared by mechanical methods. This
deposit furnished the remains of several fossils,
including reptilian teeth (KELLNER & MADER,
1997), turtles (GAFFNEY, TONG & MEYLAN, 2002),
crocodilomorphs (BUFFETAUT, 1994; BROIN, 2002)
and pterosaurs (MADER & KELLNER, 1999;
WELLNHOFER & BUFFETAUT, 1999), besides
several other vertebrate bones, including dinosaurs,
mostly found isolated (RUSSELL, 1996). The
majority of the specimens are collected by local
people and therefore the exact locality where they
were found remains unknown. This is also the case
of the avian vertebra described here, which is one of
the few remains of this clade from Africa.
DESCRIPTION
The vertebra is well preserved, despite being
incomplete (Figs.2-7). The dorsal surface of the neural
Fig.1- Map of Southern Morocco (Province of Ksar es Souk), showing the distribuition of Cretaceous deposits (stippled).
Modified from RUSSEL (1996).
AN AVIAN VERTEBRA FROM THE CONTINENTAL CRETACEOUS OF MOROCCO, AFRICA 219
Arq. Mus. Nac., Rio de Janeiro, v.62, n.2, p.217-223, abr./jun.2004
spine is partially broken, and so are the distal ends
of the transverse processes. Its overall dimensions
(Tab.1) indicate that it belonged to an animal similar
in size to a swan, Anser cygnoides Linnaeus, 1758
(Dante Martins Teixeira, Museu Nacional - Rio de
Janeiro, pers. comm.). In several places the external
surface of the bone is broken away showing that the
vertebra is light and pneumatized, although not to
the same degree as in modern birds.
The centrum is elongated, amphicoelous, cylindrical,
and slightly constricted medially. Its ventral margin
is arched upwards and no pleurocoels or foramina
are present on the lateral surface (Figs.2-3). The
articular facets of the centrum are concave and have
a subcircular outline with the dorsal margin tending
to be straight and the ventral margin pointed. The
neural canal is comparatively large (Figs.4-7), wider
mediolaterally than high dorsoventrally (Tab.1), and
exhibits a ratio height of neural canal to the height
of cranial surface of the centrum of 0.67 (Figs.4-5).
Within the neural canal, on the dorsal surface of
the centrum, is a longitudinal ridge bordered
laterally on each side by a groove. This structure,
whose function is not known, does not reach the
articular surfaces.
The neural arch is not very tall. The neural spine is
elongated anteroposteriorly and exhibits a marked
groove both cranially and caudally. There is a
prominent lateral crest (crista transversa obliqua)
that extends from the anterior proximal end of the
transverse process to the base of the neural spine
(Figs.4-5). The transverse processes are broken; no
pre- or postzygapophysis are preserved. On the left
side, a small prominence may represent the base of
the parapophysis. A well-developed ridge is present
on the anterior surface of the neural arch (the base
for the ligamentum elasticum interlaminare). One
lateral opening is observed on the base of the neural
arch, likely representing the foramen transversarium
(Figs.4-5).
DISCUSSION
The main avian feature of this vertebra is the large
neural canal, a synapomorphy of Aves (CHIAPPE &
CALVO, 1994). In the dorsal vertebrae of the extant
birds, the proportion of the height of the neural canal
to the height to cranial articular facet varies from
0.55 to 2.75mm, while in non-avian theropods, it is
less than 0.4 (CHIAPPE, 1996). As pointed out the
proportion of CMN 50852 is 0.67mm, indicating that
this specimen represents an avian taxon.
Since the specimen here is composed of one dorsal
vertebra, comparisons with other Mesozoic birds
is limited. The vertebra lacks the deep lateral
excavations present in the Ichthyornithiformes
(MARTIN & TATE, 1976), and its strongly
amphicoelic centrum differs from the heterocoelic
dorsals of Hesperornithiformes (MARTIN & TATE,
1976). The amphicoelic centrum also
distinguishes the Moroccan specimen from the
amphiplatyan dorsals of confuciusornithids
(CHIAPPE et al., 1999).
The Moroccan specimen also shows no particular
affinities with the avian taxa thus far recorded from
Gondwana. None of the dorsal vertebrae of Patagopteryx
deferrariisi Alvarenga & Bonaparte, 1992 are
amphicoelous (ALVARENGA & BONAPARTE, 1992)
Table 1. Measurements (mm) of CMN 50852, isolated avian vertebra.
FEATURES S
IZE
Maximum length of the centrum 21.0
Maximum preserved width of the neural arch 17.2
Maximum width of the centrum (mid-portion) 8.6
Minimum width of the centrum (mid-portion) 6.2
Preserved height of the vertebrae 25.6
Maximum height of cranial surface of the centrum 10.2
Maximum height of caudal surface of the centrum 10.0
Maximum width of cranial surface of the centrum 9.3
Maximum width of caudal surface of the centrum 9.7
Maximum height of the neural canal 6.8
Maximum width of the neural canal 8.0
Ratio height neural canal/ height cranial surface of the centrum 0.67
220 D.RIFF, B.MADER, A.W.A.KELLNER & D.RUSSELL
Arq. Mus. Nac., Rio de Janeiro, v.62, n.2, p.217-223, abr./jun.2004
Right lateral view of the avian vertebra (CMN 50852) from the Cretaceous strata of Morocco; fig.2- picture; fig.3- drawing.
(CTO) crista transversa obliqua, (NS) neural spine. Scale bar = 10mm.
23
Cranial view of the avian vertebra (CMN 50852) from the Cretaceous strata of Morocco: fig.4-picture, fig.5- drawing. (CTO)
crista transversa obliqua, (NS) neural spine. Scale bar = 10mm.
45
AN AVIAN VERTEBRA FROM THE CONTINENTAL CRETACEOUS OF MOROCCO, AFRICA 221
Arq. Mus. Nac., Rio de Janeiro, v.62, n.2, p.217-223, abr./jun.2004
and the dorsals of Enantiornithes are roughly
amphiplatyan, with remarkably compressed
vertebral bodies and a prominent lateral axial groove
on the centrum. Furthermore, the parapophysis in
the Enantiornithes is situated on the medial part of
the centrum (CHIAPPE, 1996).
Regarding the size of the neural canal, the
Moroccan specimen shows similarities with the
Alvarezsauridae, which is composed of
Alvarezsaurus calvoi Bonaparte,1991, Mononykus
olecranus (Perle, Norell, Chiappe & Clark, 1993)
and Patagonykus puertai Novas, 1997. The
proportion of the height of the neural canal to the
height of the cranial articular facet in Mononykus
olecranus lies between 0.75-0.58mm and in
Patagonykus puertai is 0.45mm (CHIAPPE, NORELL
& CLARK, 1997). Although the neural canal of the
dorsals in Alvarezsaurus calvoi is not prepared, this
taxon also has a large neural canal (A.W.A.Kellner,
Museu Nacional, pers. obs., 2002). The main
problem here is the controversial position of the
Alvarezsauridae in theropod phylogeny, with some
authors regarding it a member of Aves (e.g.,
NOVAS, 1996; CHIAPPE, NORELL & CLARK, 1997)
and others as non-avian theropods, closely related
with ornithomimids (BONAPARTE, 1991; MARTIN,
1995; SERENO, 1999) or as a basal Maniraptora
(NORELL, CLARK & MAKOVICKY, 2001). If the
latter is confirmed, than the large size of the neural
canal might have arisen independently in
alvarezsaurids and birds. In any case the main
difference between the Moroccan specimen and
alvarezsaurids is that the dorsal vertebra is less
compressed laterally and lacks a pronounced
ventral keel, the latter very developed in Mononykus
olecranus and to a lesser degree in Alvarezsaurus
calvoi and Patagonykus puertai (PERLE et al., 1994;
NOVAS, 1996, 1997). CMN 50852 further differs
from Patagonykus by the absence of a lateral
excavation and by being less compressed
dorsoventrally. Despite the fact that the
preservation of the dorsal vertebrae of
Alvarezsaurus does not permit an adequate
comparison with the specimen described here, the
Argentinean taxon shows only a vestigial neural
spine (BONAPARTE, 1991) and therefore is less
developed than in CMN 50852. Furthermore, the
Moroccan specimen is strongly amphicoelic
contrasting to the subamphicoelic centra (with
pleurocoels) of Alvarezsaurus calvoi (BONAPARTE,
1991), the opisthocoelic (except one that is
biconvex) cervicodorsals and dorsal vertebrae of
Caudal view of the avian vertebra (CMN 50852) from the Cretaceous strata of Morocco: fig.6- picture, fig.7- drawing. (NS)
neural spine. Scale bar = 10mm.
67
222 D.RIFF, B.MADER, A.W.A.KELLNER & D.RUSSELL
Arq. Mus. Nac., Rio de Janeiro, v.62, n.2, p.217-223, abr./jun.2004
Mononykus olecranus (PERLE et al., 1994), and the
slightly concave (tending to the procoelic condition)
of the sole dorsal known for Patagonykus puertai
(NOVAS, 1996, 1997).
Overall, the Moroccan specimen is most similar
to the dorsal vertebrae of Rahona ostromi Forster,
Sampson, Chiappe & Krause, 1998, from the Late
Cretaceous of Madagascar. This taxon forms a
basal clade within Aves, one node above
Archaeopteryx lithographica v. Meyer, 1861, or as
its sister-group (FORSTER et al., 1998). The dorsal
vertebrae of Rahona ostromi are strongly
amphicoelous with an arched centrum and neural
spines of the same form than the Moroccan
vertebra. The Morrocan specimen differs by being
comparatively longer, having a proportionally
larger neural canal and by the absence
pleurocoels, suggesting that it belongs to a
different taxon than Rahona ostromi.
CONCLUSIONS
Overall, the record of fossil Mesozoic birds from
Gondwana is scanty, particularly from Africa. Until
now, the few African osteological specimens come
from Madagascar. To our knowledge, the Moroccan
specimen is the second osteological evidence of
Mesozoic birds in northern Gondwana (besides the
occurrence in Lebanon, DALLA VECCHIA &
CHIAPPE, 2003). Its closest affinities lie with
Rahona ostromi, although the Moroccan specimen
represents an unknown basal avian group,
increasing the diversity of this clade.
ACKNOWLEDGMENTS
We are grateful to Dante Martins Teixeira (Museu
Nacional - Rio de Janeiro – MNRJ) for some
comments on the material. Maurílio O. Silva
(MNRJ) is acknowledged for the drawings
presented in this paper. We also thank Luis M.
Chiappe (Natural History Museum, Los Angeles),
Silvia Gobbo-Rodrigues (MNRJ) and an
anonymous reviewer for many comments on
earlier drafts of the ms. D. Riff thanks the
Comissão de Aperfeiçoamento de Pessoal de
Ensino Superior (CAPES) and A.W.A. Kellner
acknowledges the Conselho Nacional de
Desenvolvimento Científico e Tecnológico (CNPq)
and the Fundação de Amparo à Pesquisa do
Estado do Rio de Janeiro (FAPERJ; project E-26/
152.442/2002) for partially funding this research.
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... McFeeters (2013) reviewed the record of small-sized bones of theropods from the KKCA, concluding that most of the elements cannot be unambiguously referred to small-bodied taxa rather than immature individuals of large-bodied species. Among these elements, Riff et al. (2004) referred a small dorsal vertebra to Paraves, noting overall similarities with Rahonavis. Nevertheless, the specimen lacks unambiguous paravian or avialan synapomorphies. ...
... Nevertheless, the specimen lacks unambiguous paravian or avialan synapomorphies. In particular, the large size of the neural canal, considered by Riff et al. (2004) as an avian synapomorphy, is a size-related feature homoplastically present among all small-bodied theropods (including small abelisauroids; see Carrano, Sampson & Forster, 2002) and also non-theropod taxa (e.g., crocodyliforms; see Lio et al., 2012). Cau & Maganuco (2009) referred an isolated distal caudal vertebra from the KKCA to a new mid-sized theropod, that they named Kemkemia auditorei. ...
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We describe the partially preserved femur of a large-bodied theropod dinosaur from the Cenomanian “Kem Kem Compound Assemblage” (KKCA) of Morocco. The fossil is housed in the Museo Geologico e Paleontologico “Gaetano Giorgio Gemmellaro” in Palermo (Italy). The specimen is compared with the theropod fossil record from the KKCA and coeval assemblages from North Africa. The combination of a distally reclined head, a not prominent trochanteric shelf, distally placed lesser trochanter of stout, alariform shape, a stocky shaft with the fourth trochanter placed proximally, and rugose muscular insertion areas in the specimen distinguishes it from Carcharodontosaurus, Deltadromeus and Spinosaurus and supports referral to an abelisaurid. The estimated body size for the individual from which this femur was derived is comparable to Carnotaurus and Ekrixinatosaurus (up to 9 meters in length and 2 tons in body mass). This find confirms that abelisaurids had reached their largest body size in the “middle Cretaceous,” and that large abelisaurids coexisted with other giant theropods in Africa. We review the taxonomic status of the theropods from the Cenomanian of North Africa, and provisionally restrict the Linnean binomina Carcharodontosaurus iguidensis and Spinosaurus aegyptiacus to the type specimens. Based on comparisons among the theropod records from the Aptian-Cenomanian of South America and Africa, a partial explanation for the so-called “Stromer’s riddle” (namely, the coexistence of many large predatory dinosaurs in the “middle Cretaceous” record from North Africa) is offered in term of taphonomic artifacts among lineage records that were ecologically and environmentally non-overlapping. Although morphofunctional and stratigraphic evidence supports an ecological segregation between spinosaurids and the other lineages, the co-occurrence of abelisaurids and carcharodontosaurids, two groups showing several craniodental convergences that suggest direct resource competition, remains to be explained.
... Alternatively, this pattern may reflect a genuine paleoecological signal of an unusual, 'unbalanced' ancient ecosystem (Läng et al., 2013). By contrast, the remains of smallbodied dinosaur taxa are rare in collections and are primarily represented by isolated teeth (Amiot et al., 2004;Riff et al., 2004;Richter et al., 2013), and there is currently no unequivocal evidence of small-bodied (rather than potentially juvenile) non-avian theropods in the assemblage (McFeeters, 2013). ...
... The unusual composition of the Kem Kem assemblage has been noted and studied previously (Amiot et al., 2004;Riff et al., 2004;Läng et al., 2013;McFeeters, 2013;Richter et al., 2013). Regardless of the particular influences of taphonomy versus collecting (McGowan and Dyke, 2009), the rarity of small tetrapod specimens remains a difficult issue with which to contend when attempting to understand the original source faunas (Brown et al., 2013). ...
Article
The ‘Kem Kem beds’ of Morocco have yielded abundant material of largebodied theropod dinosaurs, but remains of small theropod taxa are rare. Here, we describe two femora that provide additional information on the diversity of small-bodied theropods in the Gondwanan mid-Cretaceous. An almost complete femur (ROM 64666) represents a noasaurid theropod based on the presence of the elongate anteromedial flange that arises from the distal shaft and terminates proximal to the distal end of the bone: osteohistological analysis indicates that it was from a juvenile individual. It is possible that this femur represents a juvenile Deltadromeus, which is recovered as a putative noasaurid in some phylogenetic analyses. Nevertheless, as the affinities of Deltadromeus are debated, this femur currently represents the first definitive record of a noasaurid from northern Africa and one of the few records of this clade from the early Late Cretaceous. Moreover, if this specimen is not a juvenile Deltadromeus then it probably represents a new addition to the Kem Kem theropod assemblage. A second partial femur (ROM 65779) can be identified only as an indeterminate averostran theropod. It is similar in size to ROM 64666, but the presence of an external fundamental system (EFS) indicates that it pertained to a small-sized adult individual. These observations indicate that the two femora described herein are from different theropod taxa, thereby demonstrating that at least one small-bodied theropod taxon was present in the Kem Kem fauna, adding to the already high theropod species-richness of this unit.
... Herbivores are rare, with only occasional remains of sauropod dinosaurs reported (Lamanna and Hazegawa, 2014;Ibrahim et al., 2016), of which Rebbachisaurus is the only named taxon (Lavocat, 1954a). A diverse assemblage of crocodylomorphs is present (Sereno and Larsson, 2009), in addition to turtles (Gaffney et al., 2002;Gaffney et al., 2006), snakes (Rage andDutheil, 2008;Klein et al., 2017) amphibians (Rage andDutheil, 2008) and possibly birds (Riff et al., 2004). ...
Article
A new genus and species of edentulous pterodactyloid pterosaur with a distinctive partial rostrum from the mid-Cretaceous (?Albian/Cenomanian) Kem Kem beds of southeast Morocco is described. The taxon is assigned to Chaoyangopteridae based upon its edentulous jaws, elongate rostrum and slightly concave dorsal outline. The rostral cross-section is rounded dorsally and concave on the occlusal surface. The lateral margins are gently convex dorsally becoming slightly wider toward the occlusal border, and a row of small lateral foramina parallel to the dorsal margin determines it as a taxon distinct from other chaoyangopterids. Apatorhamphus gyrostega gen et sp. nov. is a pterosaur of medium to large size (wingspan likely somewhere between ~3 m and ~7 m). This new species brings the number of named Kem Kem azhdarchoids to three, and the number of named Kem Kem pterosaurs to five, indicating a high pterosaur diversity for the Kem Kem beds.
... In recent decades, several theropod remains have been reported from the mid Cretaceous of North Africa (Sereno et al., 1994, 1996, 1998, Sereno, Wilson & Conrad, 2004Russell, 1996;Riff et al., 2004;Dal Sasso et al., 2005;Mahler, 2005;Novas, Dalla Vecchia & Pais, 2005;Brusatte & Sereno, 2007;Sereno & Brusatte, 2008;D'Orazi Porchetti et al., 2011;Ibrahim et al., 2014;Chiarenza & Cau, 2016;Hendrickx, Mateus & Buffetaut, 2016). Most have been referred to abelisauroids and basal tetanurans (i.e., allosauroids and spinosaurids) of medium to large body size. ...
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We describe a nearly complete pedal ungual phalanx, discovered in the Kem Kem Beds (Cenomanian) of Tafilalt region, south-eastern Morocco. The bone is symmetric, pointed, low, elongate, and almost flat ventrally in lateral aspect. This peculiar morphology allows to refer the specimen to the smallest known individual of the genus Spinosaurus. The bone belongs to an early juvenile individual and it is proportionally identical to the ungual of the third digit of a large partial skeleton recently found, suggesting an isometric growth for this part of the pes and the retention of peculiar locomotor adaptations—such as traversing soft substrates or paddling—during the entire lifespan.
... obs.). Other tetrapods include amphibians (Rage and Dutheil, 2008), diverse turtles (Gaffney et al., 2002;Gaffney et al., 2006), snakes (Rage and Dutheil, 2008;Klein et al., 2017) and, possibly, rare birds (Riff et al., 2004). ...
Article
A new genus and species, Xericeps curvirostris gen. et sp. nov., is erected for a highly distinctive pterosaur mandible from the mid-Cretaceous (?Albian to lower Cenomanian) Kem Kem beds of south east Morocco. The new taxon is referred to Azhdarchoidea based on the absence of teeth, slenderness of its mandible with sulcate occlusal surface, presence on the posterior section of the mandibular symphysis of short paired ridges bounding a central groove, and the presence of elongate foramina on its occlusal and lateral surfaces. A slight dorsal curvature determines it as a distinct genus of azhdarchoid, as does an autapomorphy: the presence of a continuous longitudinal groove on the ventral midline of the mandibular symphysis. The new species brings to three the number of named pterosaurs from the Kem Kem beds and together with an unnamed tapejarid, points to a relatively diverse pterosaur assemblage in these deposits.
... Other small theropod bones described by Russell (1996) may be uncertain indicators of total body size (distal humerus, Bone ''Taxon'' H), or were interpreted as the immature form of a larger taxon (femur, Bone ''Taxon'' M). A small dorsal vertebra described as avialan by Riff et al. (2004) was considered comparable to Rahonavis, a taxon variously assigned to Dromaeosauridae (Turner et al., 2012) or basal Avialae (Agnolin and Novas, 2011). Rauhut et al. (2012) recently suggested that some isolated teeth referred to Dromaeosauridae, such as those described from the Kem Kem beds (Amiot et al., 2004;Richter et al., in press), may instead belong to immature individuals of large-bodied basal tetanurans. ...
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Two cervical vertebrae from the Kem Kem beds of Morocco have been referred to ''Bone 'Taxon' B,'' representing a small theropod of indeterminate affinity. Reexamination of the vertebrae indicates that they are both probably from immature individuals and cannot be reliably referred to the same taxon; neither conclusively represents a small, adult theropod dinosaur. CMN 50810 has one apomorphic character, but it can only be referred to Saurischia incertae sedis. CMN 50811 is reinterpreted as representing an abelisauroid theropod, possibly a noasaurid.
... The single incomplete vertebra considered as avian by Riff et al. (2004) does not preserve any avian synapomorphies: although records of these taxa remain to be confirmed in the Kem Kem beds compound assemblage, birds were present alongside pterosaurs (GD, personal observation 2008). ...
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Fossils of vertebrates have been found in great abundance in the continental and marine early Late Cretaceous sediments of Southeastern Morocco for more than 50 years. About 80 vertebrate taxa have so far been recorded from this region, many of which were recognised and diagnosed for the first time based on specimens recovered from these sediments. In this paper, we use published data together with new field data to present an updated overview of Moroccan early Late Cretaceous vertebrate assemblages. The Cretaceous series we have studied encompasses three Formations, the Ifezouane and Aoufous Formations, which are continental and deltaic in origin and are often grouped under the name ‘‘Kem Kem beds”, and the Akrabou Formation which is marine in origin. New field observations allow us to place four recognised vertebrate clusters, corresponding to one compound assemblage and three assemblages, within a general temporal framework. In particular, two ammonite bioevents characterise the lower part of the Upper Cenomanian (Calycoceras guerangeri Zone) at the base of the Akrabou Formation and the upper part of the Lower Turonian (Mammites nodosoides Zone), that may extend into the Middle Turonian within the Akrabou Formation, and allow for more accurate dating of the marine sequence in the study area. We are not yet able to distinguish a specific assemblage that characterises the Ifezouane Formation when compared to the similar Aoufous Formation, and as a result we regard the oldest of the four ver-tebrate ‘‘assemblages” in this region to be the compound assemblage of the ‘‘Kem Kem beds”. This well-known vertebrate assemblage comprises a mixture of terrestrial (and aerial), freshwater and brack-ish vertebrates. The archosaur component of this fauna appears to show an intriguingly high proportion of large-bodied carnivorous taxa, which may indicate a peculiar trophic chain, although collecting biases alter this palaeontological signal. A small and restricted assemblage, the OT1 assemblage, possibly corre-sponds to a specific, localised ecosystem within the Kem Kem beds compound assemblage. Microfossils and facies from the Aoufous Formation, corresponding to the top of the compound assemblage, provide evidence of extremely abiotic conditions (hypersalinity), and thus of great environmental instability. At the base of the Akrabou Formation the first ammonite bioevent, Neolobites , corresponds to the onset of the marine transgression in the early Late Cenomanian while the Agoult assemblage (Late Cenomanian?) contains a variety of small fish species that have Central Tethyan affinities. Finally, the youngest Mammites bioevent in the late Early Turonian corresponds to a deepening of the marine environment: this sequence is isochronous with the Goulmima assemblage, a diverse collection of fish and other marine taxa, and shows affinities with taxa from the South Atlantic, the Central Tethys and the Western Interior seaway of North America, and further highlights the biogeographical importance of these North African
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Six quadrate bones, of which two almost certainly come from the Kem Kem beds (Cenomanian, Upper Cretaceous) of south-eastern Morocco, are determined to be from juvenile and adult individuals of Spinosaurinae based on phylogenetic, geometric morphometric, and phylogenetic morphometric analyses. Their morphology indicates two morphotypes evidencing the presence of two spinosaurine taxa ascribed to Spinosaurus aegyptiacus and? Sigilmassasaurus brevicollis in the Cenomanian of North Africa, casting doubt on the accuracy of some recent skeletal reconstructions which may be based on elements from several distinct species. Morphofunctional analysis of the mandibular articulation of the quadrate has shown that the jaw mechanics was peculiar in Spinosauridae. In mature spinosaurids, the posterior parts of the two mandibular rami displaced laterally when the jaw was depressed due to a lateromedially oriented intercondylar sulcus of the quadrate. Such lateral movement of the mandibular ramus was possible due to a movable mandibular symphysis in spinosaurids, allowing the pharynx to be widened. Similar jaw mechanics also occur in some pterosaurs and living pelecanids which are both adapted to capture and swallow large prey items. Spinosauridae, which were engaged, at least partially, in a piscivorous lifestyle, were able to consume large fish and may have occasionally fed on other prey such as pterosaurs and juvenile dinosaurs.
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Introduction Remains of possible birds are extremely rare in the Crato Formation and have so far only been reported from the Nova Olinda Member. The first report was of an isolated probable remex (Figure 18.1a) described by Martins-Neto and Kellner (1988), and subsequently refigured by Kellner et al. (1991) and Kellner (2002). Martill and Filgueira (1994) later described a semiplume, while Kellner et al. (1994) reported the occurrence of an isolated down feather. Several other feathers have since been reported from the Crato Formation (Kellner, 2002). Avian skeletal remains, although known from anecdotal accounts and personal observations, have yet to be reported in the literature and two examples are figured here for the first time (Plate 25d, Plate 26). Isolated feathers occur in both the weathered, buff-coloured laminated limestone as goethite pseudomorphs, and as carbonaceous replicas in the unweathered limestones. Specimens preserved as carbonaceous replicas may be represented by bacterial autolithifications (Martill and Frey, 1995), and in this respect the preservation mirrors that of the famous soft-tissue fossils of the Eocene Messel Formation of Germany (Wuttke, 1983). As in the case of the Crato Formation insects, fine details may be preserved in the feathers, despite the bacterial autolithification. In some cases colour patterns appear to have been preserved; in most instances as dark and light transverse bands (Plate 25). Although it has been possible to categorize these isolated feathers by comparison with modern feather morphotypes, it has not been possible to assign them to any particular taxon.
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We describe a near-complete distal caudal vertebra from an Upper Cretaceous theropod, discovered in the Kem Kem Beds (Cenomanian) of Tafi lalt, Morocco. The specimen exhibits an extremely unusual combination of features , and we herein erect a new species, Kemkemia auditorei gen. et sp. nov. The specimen differs from other theropod distal caudal vertebrae in the presence of a relatively infl ated neural canal, strongly reduced zygapophyses, a low but very robust neural spine bearing shallow lateral fossae, a mediolaterally concave dorsal surface of the neural spine, and coalescence of the postzygapophyses in a position more proximal than the region where neural spines are absent. Although Kemkemia shares some derived features with neoceratosaurs, we provisionally refer it to Neotheropoda incertae sedis, pending the discovery of more complete material. Several distal caudal vertebrae from the Maastricthian of India are similar to Kemkemia, and may belong to a closely related taxon.
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The newly organized Long Island Natural History Museum (LINHM) has assembled a small collection of fossil vertebrates from the Cretaceous of Morocco. Among the remains in this collection are two spinosaurid (Theropoda) teeth and one sauropod tooth that we refer to either the Diplodocidae or Titanosauridae. Because of the scarcity of spinosaurid and Cretaceous sauropod teeth, a short description of the material is presented here. In addition to the dinosaurian remains, the collection includes an unidentified crocodilian tooth and a tooth identified tentatively as that of a pterosaur, which we also describe briefly. Furthermore, there are other fossil reptile teeth from the Ksar es Souk Province in the collections of the LINHM. Some of these may represent groups of reptiles other than those discussed here, but the taxonomic identity of these teeth is still being determined.
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A new crocodilian taxon, Hamadasuchus rebouli n.g., n.sp., is described on the basis of a left dentary from the Cretaceous red beds (Late Albian to basal Cenomanian) of the Hamada du Guir in southern Morocco. This ziphodont form with compressed and serrated posterior teeth is referred to the family Trematochampsidae. -Author
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The 'Gres rouges infracenomaniens' of southern Morocco, possibly of Albian age, contain evidence of one of the most diversified dinosaur assemblages known from Africa, including a relatively long-necked species of Spinosaurus and abundant but isolated bones of a peculiar theropod ('Spinosaurus B' of Stromer 1934). Also preserved are the oldest records of abelisaurids and among the oldest records of titanosaurids in Africa. Bones of infantile didnosaurs are present. The assemblage resembles that of the Bahariya Formation more than that of Gadoufaoua, possibly because of a trophic dependence upon large, freshwater fishes. It was more closely linked zoogeographically to South America than to North America.