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Noguerornis gonzalezi (Aves: Ornithothoraces) from the Early Cretaceous of Spain

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Noguerornis - Chiappe & Lacasa-Ruiz - Page 1
NOGUERORNIS GONZALEZI (AVES) FROM THE EARLY CRETACEOUS OF SPAIN
LUIS M. CHIAPPE
1
AND ANTONIO LACASA-RUIZ
2
1
Department of Ornithology, American Museum of Natural History, Central Park West at 79
th
Street, New York, NY 10024, USA;
2
Sección Paleontología, Institut d’Estudis Ilerdencs, Pza. La Catedral s/n, 25002 Lleida, Spain
Running Head: Noguerornis gonzalezi
Noguerornis - Chiappe & Lacasa-Ruiz - Page 2
INTRODUCTION
The first Mesozoic avian remains from the Iberian Peninsula were reported by Vidal
(1902), who mentioned the accidental destruction of a fossil bird from the Lower Cretaceous
quarry of “ La Pedrera de Meiá” (42 01’ N; 4 35’ W) in the Spanish Province of Lleida,
Catalonia (Lacasa-Ruiz, 1985). In subsequent years, this site yielded a large number of isolated
feathers (Lacasa-Ruiz, 1985; Gómez Pallerola, 1986; Kellner, this volume). However, the first
significant discoverythe skeletal remains of Noguerornis gonzaleziwas not made until the
1980’s (Lacasa-Ruiz, 1986, 1989a, b, 1991a).
The discovery of Early Cretaceous avians from Spain provided relevant new information
about the early evolution of birds, clarifying the early pattern of morphological transformation
(see Sanz et al., 1988, this volume; Chiappe, 1991, 1995a), and establishing the earliest records
of volant birds with enhanced aerodynamic specializations (Sanz et al., 1988, 1996, this volume;
Chiappe, 1995b). The significance of the spectacular specimens of Iberomesornis romerali (Sanz
and Bonaparte, 1992; Sanz et al., this volume), Concornis lacustris (Sanz and Buscalioni, 1992;
Sanz et al., 1995, this volume), and Eoalulavis hoyasi (Sanz et al., 1996, this volume) was
immediately recognized (see Cracraft, 1988; Milner, 1993; Padian, 1996); this was not the case,
however, for the less complete Noguerornis gonzalezi. Although several papers by Lacasa-Ruiz
(e.g., Lacasa-Ruiz, 1986, 1989a, b, 1991a) remarked upon the peculiarities and significance of
Noguerornis (one of the earliest known avian members), this information has remained virtually
unnoticed. In this paper, after further mechanical preparation, we provide a detailed description
of the holotypeand still unique specimenof Noguerornis, and discuss both its relationships to
other basal birds and its contribution to our understanding of early avian evolution.
GEOLOGICAL SETTING
The Sierra del Montsec is roughly 65 km north of the town of Lleida (Catalonia),
extending approximately 50 km from east to west (Fig. 1). The rivers Noguera Pallaresa and
Noguera Ribagorzana cross the Montsec range at right angles. In the eastern region of the
Montsec range, on the eastern slope of the valley of the Noguera Palleresa, there is a famous
quarry of lithographic limestones that since 1902 has yielded numerous well-preserved fossils of
continental facies (Lacasa-Ruiz, 1991b; Martínez-Delclós, 1991a, 1995). This quarry gained
prominence as an important paleontological site when, at the end of the 19
th
century, a small
mining company started to process the fine stone for lithographic purposes. Mining engineer L.
M. Vidal (1902) was pivotal in recognizing the importance of this fossil site and reporting, along
with other workers, the first fossil findings. The quarry reported by Vidal (1902) is known as “
Las Calizas Litográficas de Santa María de Meyá” (also known as “ La Pedrera de Meiá,” “ La
Pedrera de Rúbies,” or simply “ La Pedrera” ) in reference to its proximity to the town of Santa
María de Meyá. In more recent years, a second quarry was found nearby; this second quarry has
been named “ La Cabrúa.”
Vidal (1902) proposed a Kimmeridgian (Late Jurassic) age for the lithographic limestones
of Montsec. Later studies, however, determined the age of these deposits as Early Cretaceous, but
did not arrive at a consensus regarding their precise age (Fig. 2). Whereas paleofloristic (Barale,
1973, 1991, 1995) and ostracod (Peybernés and Oertli, 1972; Brenner et al., 1974) data placed
these beds within the Late Berriasian-Early Valanginian, recent charophyte studies point to a
younger, Late Hauterivian-Early Barremian age (Martín-Closas and López-Morón, 1995).
FIGURE 1. Map indicating the area of the Montsec range within the Province of
Lleida, Catalonia (Spain), where the holotype of Noguerornis gonzalezi was
found.
Noguerornis - Chiappe & Lacasa-Ruiz - Page 3
Peybernés (1976) defined this 50-meter thick deposit of lithographic limestones as “
calcaires lithographiques á plantes et vertébrés de La Pedrera de Rúbies” (Unit N2) and included
it within a unit named by himself as “ Calcaires á Charophites du Montsec.” This unit has also
been referred as “ La Pedrera de Rúbies Lithographic Limestones” (see Fregenal-Martínez and
Meléndez, 1995).
Rocks at “ La Pedrera” are rhythmically laminated lithographic limestones deposited in
the distal areas of a lake that developed under a warm, subtropical-semiarid climate (Fregenal-
Martínez and Meléndez, 1995). During the Early Cretaceous, the Iberian Plate was close to the
30N parallel, and this lake was in the proximity of the seashore. However, the presence of a
marine connection with the predominantly freshwater environment has not been definitively
established (Fregenal-Marnez and Meléndez, 1995).
The fossil biota yielded by the “ La Pedrera de Rúbies Lithographic Limestones” is highly
diverse (Martínez-Delclós, 1991a, 1995). The record of plants (Barale, 1991, 1995) is composed
of pteridophytes (Ferns and Equisetales), prespermatophytes (e.g., Ginkyoales, Cycadales,
Bennettitales), and spermatophytes (Coniferales and Angiospermae), along with spores of algae
and bryophytes. The fossil fauna is composed of mollusks (Martinell and Domenech, 1991),
crustaceans (Lacasa-Ruiz and Via, 1991), arachnids (Selden, 1991), abundant insects (Martínez-
Delclós, 1991b), and vertebrates. Vertebrate fossils are known primarily by the abundant “
holosteans” and teleostean fishes (Wenz, 1991a), anurans (Wenz, 1991b), non-avian reptiles
(Buscalioni and Sanz, 1991), and birds (Lacasa-Ruiz, 1989a, b, 1991b). The avian fossil remains
comprise approximately 25 specimens of isolated feathers (see Lacasa-Ruiz, 1985; Kellner, this
volume), the holotype of Noguerornis gonzalezi (Lacasa-Ruiz, 1989a), and the enantiornithine
hatchling reported by Sanz et al. (1997).
SYSTEMATIC PALEONTOLOGY
Taxonomic Hierarchy
Aves Linnaeus, 1758
Ornithothoraces Chiappe, 1995
Enantiornithes Walker, 1981
Noguerornis gonzalezi Lacasa-Ruiz, 1989
HolotypeSlab numbered LP.1702 P (collection from “ La Pedrera,” Institut d’Estudis
Ilerdencs, Lleida, Spain), including portions of both humeri, radii, and carpometacarpi, left ulna,
furcula, tibia, three trunk vertebrae, pelvis, other osseous remains, and feathers (Fig. 2).
Locality and HorizonLa Pedrera de Meiá, Sierra del Montsec, Province of Lleida, Spain. “ La
Pedrera de Rúbies Lithographic Limestones,” Lower Cretaceous, Upper Berriasian-Lower
Barremian.
DiagnosisNoguerornis gonzalezi is diagnosed by the presence of a strongly curved humerus, a
clear autapomorphy of this taxon.
ANATOMY
Noguerornis gonzalezi is preserved on a single slab (Fig. 2). Although most bones are
incomplete, significant anatomical details are visible on both their preserved portions and the
impressions left by them on the rock. Based on furcular and humeral comparisons, Noguerornis
Noguerornis - Chiappe & Lacasa-Ruiz - Page 4
is intermediate in size between the smaller Iberomesornis (Sanz and Bonaparte, 1992) and the
larger Concornis (Sanz et al., 1995) and Eoalulavis (Sanz et al., 1996).
Vertebral Column
The most caudal thoracic vertebra and the cranial two synsacral vertebrae are preserved.
These three elements lay on their right lateral side within the pelvic remains, exposing their left
lateral sides (Figs. 2, 3, 4C).
The caudalmost thoracic vertebra shows a broad depression excavating its centrum,
although it is not clear whether this is an artifact of its preservation. A broad lateral fossa is
present in the thoracic centra of several enantiornithine taxa (Chiappe and Walker, this volume),
Confuciusornis (Chiappe et al., 1999), Ichthyornis (Marsh, 1880), and some neornithine birds
(e.g., charadriiforms, procellariiforms). The articular surfaces of the thoracic and synsacral
vertebrae are apparently amphyplatic. The spinal processes are broad and laminar, with their
craniodorsal apex projected cranially (Figs. 3, 4C). In the caudal thoracic vertebra, a small cranial
zygapophysis is preserved. The two synsacral vertebrae are fused to each other, although the
boundary between them is still visible. The spinal processes of these two elements form a
continuous spinal crest. Zygapophyses are not preserved in these synsacral vertebrae.
Thoracic Girdle and Limb
FurculaThe furcula of Noguerornis is preserved nearly complete, and exposed
apparently in ventral view. It is robust and U-shaped, having ventral and medial faces that are
nearly flat and perpendicular to each other. The interclavicular angle is approximately 46
. The
furcula bears a hypertrophied hypocleideum which, as in the enantiornithine Cathayornis (Zhou,
1995) and Eoalulavis (Sanz et al., 1996), exceeds half the length of the clavicular rami. The
hypocleideum is thin, relatively compressed, and tapers distally (Figs. 2, 3, 4B).
HumerusThe left humerus is articulated with the ulna and radius, while the right
element is disarticulated. The humerus of Noguerornis is shorter than the ulna and radius, a
condition shared by most ornithothoracines (Chiappe, 1996). It is robust and strongly curved,
with a convex dorsal margin and a concave ventral one (Figs. 2, 3, 4C). The proximal end is
better preserved in the right, disarticulated element, being exposed in its cranial aspect. In this
view, the proximal border of the head is slightly inclined dorsally (Fig. 4C). A slight depressed
area located just distal to the proximal margin is dorsally and ventrally bordered by smooth
elevated areas. As in other basal birds (e.g., Enantiornithes, Patagopteryx) and non-avian
theropods (e.g., Deinonychus), the humeral head is concave cranially, and presumably convex
caudally. There is a short bicipital area ventral to the head (Fig. 4C). The distal end is badly
preserved in both humeri; in the left element, which is exposed caudally, the olecranon fossa is
poorly developed.
UlnaOnly the left ulna is preserved, exposed in dorsal aspect. Both distal and proximal
ends are damaged. The shaft is nearly straight, round in cross-section, and uniformly broad (Figs.
2, 3). The midshaft width appears to be only slightly broader than the radial midshaft (Table I).
The papillae for the remigial feathers are absent.
RadiusThe left radius is preserved in articulation with the humerus, ulna, and
carpometacarpus; the right element is disarticulated and mostly preserved as an impression on the
slab. The radius of Noguerornis is straight, uniformly wide, and subcylindrical in cross-section
(Figs. 2, 3). The distalmost end curves slightly caudalward. The proximal end is not preserved in
Noguerornis - Chiappe & Lacasa-Ruiz - Page 5
either radii. In contrast to the condition of some Enantiornithes (Chiappe and Calvo, 1994;
Chiappe and Walker, this volume), the radial shaft of Noguerornis lacks a caudal, axial groove.
CarpometacarpusOnly the shaft and proximal portion of the carpometacarpi are
preserved. Despite previous statements (Lacasa-Ruiz, 1989a), the three metacarpals of the hand
of Noguerornis are not unfused; they are indeed fused, at least in their most proximal end (Figs.
2, 3, 4C). A semilunate carpalcorresponding to the semilunate bone of non-avian
theropodsis coosified with the metacarpals (mostly the major and alular ones), a condition
more clearly visible under ultraviolet light. The alular metacarpal is small, forming a semicircular
medial margin without a development of an extensor process (Fig. 4A). The central area of this
metacarpal possesses a round depression on its dorsal face. Articulated to the alular metacarpal of
the left element is a spine-like proximal phalanx, with the distal end missing. The major
metacarpal is broader and more robust than the minor one. These two metacarpals are firmly
united throughout their length, leaving no intermetacarpal space (Fig. 4A). The distal end is
missing in both carpometacarpi. The impression left by the most distal portion of the right
element, however, indicates that the major and minor metacarpals curve cranially (Fig. 4A) and
that, as in Enantiornithes (Zhou, 1995; Chiappe and Walker, this volume), the latter was the
longer.
Pelvic Girdle and Limb
IschiumAmong the presumable pelvic remains, only the ischium, which is exposed
dorsally, can be confidently identified (Figs. 2, 3, 4C). The ischium of Noguerornis is a laminar,
strap-like bone that gradually narrows distally. On its proximal half, this bone possesses a large,
hook-shaped process (Fig. 4A). Pending the interpretation of its position as either cranially or
caudally oriented, this process can be alternatively regarded as a large obturator process
(Chiappe, 1995b) or the proximodorsal ischiadic process of several other basal birds (e.g.,
Enantiornithes, Confuciusornis, Unenlagia, Rahonavis) (see Martin, 1995; Hou et al., 1995;
Novas and Puerta, 1997; Forster et al., 1998a, b; Chiappe et al., 1999; Chiappe and Walker, this
volume). Although the poor preservation of the ischium prevents clarification of this structure,
the fact that a proximodorsal process is widespread among basal birds and a prominent obturator
process is not makes more probable the identification of the ischiadic process of Noguerornis as
the proximodorsal ischiadic process. It is clear, on the other hand, that both ischia contact each
other on their distal halves, forming a long symphysis. This is of particular interest, as no other
Mesozoic bird has been shown to have an ischiadic symphysis. An ischiadic symphysis has not
been definitively reported for Archaeopteryx (Wellnhofer, 1974, 1993), Rahonavis (Forster et al.,
1998a, b), or Iberomesornis (Sanz and Bonaparte, 1992), and the ischia are separated from each
other in Confuciusornis (Chiappe et al., 1999), Patagopteryx (Chiappe, 1996), Ornithurae
(Marsh, 1880; Baumel and Witmer, 1993), and those enantiornithines for which data are
available (e.g., Concornis; Sanz et al., 1995). An ischiadic symphyis is also absent in
dromaeosaurid theropods (Norell and Makovicky, 1997).
TibiaThe straight limb bone perpendicular to the right humerus is interpreted as the
tibia. This interpretation is based on the fact that the bone exhibits a crest (considered the fibular
crest), and that the most distal portion is craniocaudally compressed, as is typical of avian
tibiotarsi (Figs. 2, 3). It is not possible to discern if it is a right or left element.
Feathers
FIGURE 2. Holotype of Noguerornis gonzalezi (LP.1702.P) under ultraviolet light.
Scale bar = 1
cm.
FIGURE 3. Holotype of Noguerornis gonzalezi (LP.1702.P). Abbreviations: al1,
proximal phalanx of alular digit; alm, alular metacarpal; fur, furcula; hum, humerus;
hyp, hypocleideum; isc, ischium; isp, ischiadic process (see text for interpretation);
mam, major metacarpal; mim, minor metacarpal; pc, proximal carpal; rad, radius; sv1,
first synsacral vertebra; sv2, second synsacral vertebra; tib, tibia; tv, thoracic vertebra;
uln, ulna. Scale bar = 1 cm.
Noguerornis - Chiappe & Lacasa-Ruiz - Page 6
Two main aggregations of feathers, corresponding to wing feathers, are preserved.
Isolated coverts are also visible on the slab. The secondary remiges are directed at an angle of
70
with respect to the ulnar shaft on the left ulna. Portions of coverts are preserved cranial to the
left radius and proximal end of the left humerus, suggesting the development of a propatagium.
Unfortunately, the internal structure of these feathers is not preserved.
PHYLOGENETIC RELATIONSHIPS
The avian relationship of Noguerornis gonzalezi is unquestionably supported by the
combination of feathers with derived characters that are either exclusive to birds (e.g., U-shaped
furcula with a hypertrophied hypocleideum, ulna longer than humerus) or uncommon among
non-avian theropods (e.g., carpometacarpus). Yet the fragmentary nature of the holotype, and
only known specimen, complicates any attempt of understanding the relationships of this species
to other basa birds.
Martin (1995) placed Noguerornis within the Enantiornithes, allying it to both
Iberomesornis and Concornis. This claim was based on the purported similarity of the humeri
and furcula of these taxa, and the alleged presence of a broad distal humeral end bearing a short
articular surface (supposed to be found in Enantiornithes). The remarkable curvature of the
humerus of Noguerornis, however, is unique, and it makes this bone quite unlike that of either
Iberomesornis or Concornis. In addition, the hypocleideum of the furcula of the latter two taxa
(based on what it is known) is definitely shorter than that of Noguerornis. Whereas the furcula of
Iberomesornis differs from that of Concornis in lacking the euenantiornithine lateral excavation
(Chiappe and Calvo, 1994; Sanz et al., 1995, 1996; Chiappe and Walker, this volume), the
presence or absence of this condition remains uncertain in the available material of Noguerornis.
Furthermore, Martin’s observations of the distal end of the humerus of Noguerornis are
equivocal because the distal ends of the humeri of the only known specimen are completely
abraded, preserving no other details besides a weak olecranon fossa on the left element.
Kurochkin (1995) also supported the inclusion of the Spanish bird within Enantiornithes.
This claim was based on the presence of a “sharp-angled furcula with hypocleideum, pronounced
external and internal tuberosities of the proximal humerus, oblique-shaped distal humerus with
the distal protrusion of the internal condyle, and metacarpals fused only proximally.” Apparently,
the condition of the furcula simply refers to the presence of both a low interclavicular angle and a
hypocleideum, attributes that are clearly not exclusive to Enantiornithes within birds (Chiappe,
1996). Furthermore, Kurochkin’s (1995) observations of the humerus are not manifest in the
poorly preserved material, and whether minor (III) and major (II) metacarpals fuse to each other
only proximally is also uncertain because the distal ends of these metacarpals are not preserved
but known only from the impressions left by the right elements (Fig. 4A).
Thus, the allocation of Noguerornis within Enantiornithes, as expressed by Martin (1995)
and Kurochkin (1995), does not seem to have any evidential support. This, however, does not
mean that Noguerornisand at least certain Enantiornithesdo not share some derived
characteristics. As pointed out by Zhou (1995), the furcula of the enantiornithine Cathayornis has
a long hypocleideum, which exceeds half the length of the clavicular rami. This condition is
comparable to that of Noguerornis and the enantiornithine Eoalulavis (Sanz et al., 1996).
Likewise, the carpometacarpus of both Cathayornis and Noguerornis has a rounded medial
margin lacking an extensor process and the minor metacarpal appears to be longer than the major
Noguerornis - Chiappe & Lacasa-Ruiz - Page 7
metacarpal and slightly curved distally. These two conditions are comparable to that of other
enantiornithines (see Chiappe and Walker, this volume).
In any case, the relationships of Noguerornis to other birds should be examined on the
basis of the distribution among taxa of all the characters available for study in the Spanish bird.
In this cladistic framework (Chiappe, this volume), Noguerornis is clustered with all
Ornithothoraces by the fusion of the semilunate carpal and the metacarpals and a U-shaped
furcula with an interclavicular angle smaller than 90
. Within Ornithothoraces, the well-
developed hypocleideum and distal projection of the minor metacarpal, which extends distally
more than the major metacarpal, group Noguerornis together with Enantiornithes and
Iberomesornis (Fig. 5), although this last character is missing in the latter taxon. Noguerornis,
however, lacks several derived characters of Euenantiornithes such as the presence of a concave
central portion of the proximal margin of the humeral head, a prominent bicipital crest of the
humerus, and a longitudinal groove on the shaft of the radius (Chiappe and Walker, this volume).
The absence of a procoelous synsacrum clusters Noguerornis with Iberomesornis (Chiappe, this
volume) (Fig. 5). The sister-taxon relationship between these taxa and between them and
Euenantiornithes (Fig. 5) is weakly supported. Nevertheless, the result of Chiappe’s analysis (this
volume) suggests that together with Iberomesornis, Noguerornis is likely a close outgroup of
Euenantiornithes. Characters that appear to be plesiomorphic for Ornithothoraces, such as its
ischiadic symphysis and the subequal diameter of the ulna and radius, may indeed be
homoplastic. This is very likely the case for the ischiadic symphysis which is definitively absent
in Confuciusornis (Chiappe et al., 1999) and dromaeosaurid theropods (Norell and Makovicky,
1997).
PALEOBIOLOGY
The fragmentary nature of the single known specimen of Noguerornis gonzalezi prevents
inferring much about its lifestyle. Nevertheless, the modern proportions and general aspect of its
wing (e.g., ulna-radius longer than humerus, distal carpals fused to metacarpals) suggest that this
bird was capable of some sort of flight. In agreement with this is the presence of a U-shaped
furcula with an enlarged hypocleideum. The U-shape of the furcula of Noguerornis which is in
contrast to the boomerang shape of that of Archaeopteryx and non-avian theropodssuggests
that this element may have functioned as a spring, bending laterally during downstroke and
recoiling during upstroke, a mechanical property observed in several neornithine birds (Jenkins et
al., 1988; Bailey and DeMont, 1991). Although the functional correlation of this mechanical
characteristic is not fully understood (Bailey and DeMont, 1991), this property of the avian
furcula is essential for a postulated secondary respiratory cycle in connection with the increased
metabolic demands of flight (Jenkins et al., 1988). Likewise, the long hypocleideum of
Noguerornis may have provided a larger area for the attachment of the coracoclavicular
membrane, enlarging the area for the most cranial origin of the M. pectoralis (Olson and
Feduccia, 1979), the main flight muscle (Raikow, 1985; Dial et al., 1987, 1988), as well as
providing additional strength to the thoracic girdle as suggested by Sanz et al. (1996) for the
enantiornithine Eoalulavis. Perhaps the strongest evidence in support of the flying capabilities of
Noguerornis rests on the presence of a propatagium (Fig. 2), the largest of the wing patagia. This
feathered skinfold has been regarded as indispensable for flight (Brown et al., 1994, 1995). A
propatagium has never been reported for Archaeopteryx. Interestingly, however, a 19
th
century
sketch of the Berlin specimen shows a fold of feathers in between the humerus and the ulna-
FIGURE 5. Cladogram illustrating the phylogenetic relationships of Noguerornis
gonzalezi to other birds (see Chiappe, this volume).
Noguerornis - Chiappe & Lacasa-Ruiz - Page 8
radius (see Ostrom, 1985), suggesting that a propatagium may indeed have been present in
Archaeopteryx. Nevertheless, given the fact that this area of the Berlin specimen has not been
prepared, and also that examination of this and other specimens fails to document the presence of
a propatagium, it seems quite likely that the ‘propatagium’ of this early sketch is simply
inaccurate. Therefore, it appears that Noguerornis is the earliest bird for which a definitive avian
propatagium is known.
The occurrence of a propatagium in such an ancient bird adds to our knowledge of the
early evolution of flight. The presence of this airfoil implies that a ligamentum propatagiale was
already developed on the leading edge of the wing, between the shoulder and the carpus. The
modern avian ligamentum propatagiale fulfills a crucial role in the wing’s extension-flexion
mechanism and is essential for avoiding distortion of this surface, allowing the wing’s proper
function as an airfoil. As hypothesized by Brown et al. (1995), the ligamentum propatagiale may
also support the distal portion of the wing against drag. This modern design of the wing’s airfoil
and control appears to have been present in Noguerornis, one of the earliest known birds after
Archaeopteryx.
ACKNOWLEDGMENTS
We are grateful to N. Frankfurt and S. Copeland for preparing some illustrations, and to
D. Treon and S. Orell for editorial assistance. Support for this research was provided by grants to
L. Chiappe from the Dinosaur Society and the Guggenheim Foundation.
Noguerornis - Chiappe & Lacasa-Ruiz - Page 9
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TABLE I. Measurements in millimeters of Noguerornis gonzalezi.
Left Right
Maximum width of proximal end of humerus 4.6 4.6
Maximum width of distal end of humerus 4.2 4.7
Maximum width of midshaft of humerus 1.8 2
Maximum length of ulna 24.3 -----
Maximum width of midshaft of ulna 1.3 -----
Maximum length of radius 23.1 23.2
Maximum width of midshaft of radius 0.9 0.9
Maximum width of proximal end of carpometacarpus 2.9 2.9
Maximum width of proximal end of alular metacarpal 1.1 1.1
Maximum width of proximal end of major metacarpal 1.2 1
Maximum width of proximal end of minor metacarpal 0.7 0.7
Maximum length of clavicular branch 9.3 10
Maximum length of hypocleideum 5.3 -----
Maximum length of trunk vertebra 1.6 -----
Maximum length of first synsacral vertebra 2 -----
Maximum length of second synsacral vertebra 2.4 -----
Length of ischium from the obturator process to distal end 10.5 -----
Noguerornis - Chiappe & Lacasa-Ruiz - Page 14
... from Las Hoyas, Cuenca , and references therein); Noguerornis gonzalezi and Enantiornithes indet. are known from El Montsec, Lleida (Lacasa Ruiz, 1989;Chiappe and Lacasa Ruiz, 2002). ...
... The holotype of Noguerornis gonzalezi Lacasa Ruiz, 1989, includes three trunk vertebrae, furcula, humeri, radii, ulna, three metacarpals of the hand, carpal, phalanx, ischium, tibia, and wing feather impressions; most bones are incomplete (Lacasa Ruiz, 1989;Chiappe and Lacasa Ruiz, 2002). N. gonzalezi is characterized by the presence of a strongly curved humerus and an ischiadic symphysis (Chiappe and Lacasa Ruiz, 2002). ...
... The holotype of Noguerornis gonzalezi Lacasa Ruiz, 1989, includes three trunk vertebrae, furcula, humeri, radii, ulna, three metacarpals of the hand, carpal, phalanx, ischium, tibia, and wing feather impressions; most bones are incomplete (Lacasa Ruiz, 1989;Chiappe and Lacasa Ruiz, 2002). N. gonzalezi is characterized by the presence of a strongly curved humerus and an ischiadic symphysis (Chiappe and Lacasa Ruiz, 2002). It is regarded as a basal enantiornithine bird closely related to Iberomesornis (Chiappe, 2001). ...
... While other groups of Early Cretaceous birds are only known from Asia (O'Connor et al., 2011a), enantiornithines were already widespread in the Early Cretaceous. In Europe, the earliest member of this group (genus Noguerornis) has been found in Montsec limestones in northern Spain, which are dated within the interval from Late Berriasian to Early Barremian, i.e., obviously older than 125 Ma (see Chiappe and Lacasa-Ruiz, 2002;Selden and Nudds, 2012). Three more genera (Iberomesornis, Concornis, and Eoalulavis) are known from the Barremian-Aptian boundary beds (about 125 Ma) of Spain (Sanz et al., 1988;Sanz and Bonaparte, 1992;Sanz and Buscalioni, 1992;Sanz et al., 1996). ...
... This geographical distribution formally supports the idea of the Laurasian origin of this group (Zhou, 1995). It is important that the earliest Protopteryx and members of the family Pengornithidae (which includes the genus Eopengornis) are also regarded as the morphologically most primitive members of Enantiornithes, which are distinguished from typical enantiornithines by a number of morphological details (see below); Noguerornis also displays a structural character primitive for enantiornithines, i.e., the humerus lacking a concave surface in the central part of the caput humeri (caput humeri is more or less globular: Chiappe and Lacasa-Ruiz, 2002). It is noteworthy that a globular caput humeri characteristic among enantiornithines only of Pengornithidae is also described in Brazilian Cratoavis (Carvalho et al., 2015a(Carvalho et al., , 2015b. ...
Article
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New data on the taxonomic and morphological diversity of Early Cretaceous Enantiornithes are reviewed. A new hypothesis concerning the phylogenetic position of Pengornithidae is proposed. These birds traditionally treated as primitive enantiornithines may in fact be more closely related to Ornithuromorpha. This phylogenetic placement implies that the fan-shaped tail and modern-type humeral joint was formed once in the early evolution of birds. Hence, the similarity between Pengornithidae and other enantiornithines may be plesiomorphic. The ecology of Early Cretaceous enantiornithines is discussed. The increased mobility of neck in Holbotia is possibly accounted for by the cranioinertial swallowing mechanism, as in modern ratites. The hypotheses of scansorial adaptations in Parapengornis and Fortunguavis are criticized. In addition, the phylogenetic position of Mystiornis is discussed.
... In addition, the only reported Late Cretaceous bird, the holotype of the . Outside China, several enantiornithines preserving feathers are known from the Early Cretaceous of Spain: the holotype of Eoalulavis hoyasi (Sanz et al. 1996), the pellet LH 11386 consisting of several juveniles (Sanz et al. 2001), and the isolated wing MCCMLH31444, all from the 125 Ma Las Hoyas Konservat-Lagerstätten (Navalón et al. 2015) and the holotype of Noguerornis gonzalezi from the Upper Berriasian-Lower Barremian "La Pedrera de Meiá" Limestones (Chiappe and Lacasa-Ruiz 2002;Lacasa-Ruiz 1988). The partial specimens representing the holotype materials of Hoboltia ponomarenkoi from Mongolia (Zelenkov and Averianov 2016) and Enantiophoenix electrophyla from Lebanon (Cau and Arduini 2008;Dalla Vecchia and Chiappe 2002) also preserve feather traces, but these are uninformative. ...
Chapter
Early bird plumage is well known primarily due to numerous discoveries of specimens preserving feathers from Early Cretaceous deposits in China. Remiges and rectrices are most commonly preserved with rectrices showing the greatest variation. The long boney-tailed Jeholornis has a unique tail plumage employing two anatomically distinct rectricial pterylae serving both aerodynamic and ornamental functions. Basal pygostylians show disparate tail plumages that are reflected by differences in pygostyle morphology. Sapeornis has a proportionately shorter pygostyle wielding a fan-shaped array of rectrices, whereas the robust pygostyle of Confuciusornis is associated with a pair of elongate rachis-dominated feathers in some specimens, considered indicative of sexual dimorphism. The latter morphology is also present in many enantiornithines. Members of this diverse clade have primarily ornamental tail morphologies, whereas the earliest members of the Ornithuromorpha all possess tail morphologies that appear to be primarily aerodynamic. Body feathers in Archaeopteryx and adult enantiornithines trapped in amber are pennaceous suggesting that reported rachis-less body feathers in Jehol birds may be taphonomic artifacts. Rarely preserved, well-developed pennaceous crural feathers are present in Archaeopteryx and some enantiornithines, whereas crural feathers are short in the Confuciusornithiformes. Their preserved absence in nearly all Jehol ornithuromorph specimens most-likely reflects the smaller available sample size. Crural feathers in many basal ornithuromorphs were probably reduced, as in Yanornis and extant aquatic and semiaquatic birds. Overall, early birds show a trend towards the reduction of the distal hindlimb feathers present in closely related nonavian dinosaurs. However, well-developed tarsometatarsal feathers are present in Sapeornis and two exceptionally well-preserved enantiornithine specimens indicate this group was diverse in the distal extent of their hindlimb plumage, including at least one lineage with feathered pedal digits. Although remarkably modern in many aspects, early bird plumage still differed from that of their modern counterparts including extinct morphotypes and differences in ontogenetic patterns.
... In addition, the only reported Late Cretaceous bird, the holotype of the . Outside China, several enantiornithines preserving feathers are known from the Early Cretaceous of Spain: the holotype of Eoalulavis hoyasi (Sanz et al. 1996), the pellet LH 11386 consisting of several juveniles (Sanz et al. 2001), and the isolated wing MCCMLH31444, all from the 125 Ma Las Hoyas Konservat-Lagerstätten (Navalón et al. 2015) and the holotype of Noguerornis gonzalezi from the Upper Berriasian-Lower Barremian "La Pedrera de Meiá" Limestones (Chiappe and Lacasa-Ruiz 2002;Lacasa-Ruiz 1988). The partial specimens representing the holotype materials of Hoboltia ponomarenkoi from Mongolia (Zelenkov and Averianov 2016) and Enantiophoenix electrophyla from Lebanon (Cau and Arduini 2008;Dalla Vecchia and Chiappe 2002) also preserve feather traces, but these are uninformative. ...
Chapter
Several stem birds, such as Confuciusornithidae and Enantiornithes, were characterized by the possession of one or two pairs of conspicuous, elongated tail feathers with a unique morphology, so-called rhachis-dominated racket plumes. In the past, several studies reported contradictory interpretations regarding the morphology of these feathers, which sometimes failed to match with any morphology known from modern feathers. In this chapter, these interpretations are reviewed and compared with various modern feather types. The comparison confirms recent interpretations that the rhachis-dominated racket plumes are highly modified pennaceous feathers with ornamental function, originating at least two times independently from each other during evolution. While the gross organization (i.e., a short distal vane and a long, naked rhachis) of these feathers resembles that of filoplumes, they resemble pennaceous body feathers of penguins in terms of rhachis morphology and pigmentation pattern. As the rhachis-dominated racket plumes combine different morphologies that are apparent among modern feather types, this extinct morphotype does in fact not show any aberrant morphological novelties, but rather fall into the morphological and developmental spectrum of modern feathers.
... Ornithurae). Although the fossil record of propatagium is still patchy, presence of this soft structure has been recently documented in Microraptor (see Xu et al. 2003), Anchiornis (see ), Archaeopteryx (Martin and Lim 2005), and Enantiornithes (e.g., Noguerornis; Chiappe and Lacasa Ruiz 2002). Moreover, all known averaptorans (e.g. ...
... Ornithurae). Although the fossil record of propatagium is still patchy, presence of this soft structure has been recently documented in Microraptor (see Xu et al. 2003), Anchiornis (see ), Archaeopteryx (Martin and Lim 2005), and Enantiornithes (e.g., Noguerornis; Chiappe and Lacasa Ruiz 2002). Moreover, all known averaptorans (e.g. ...
... Ornithurae). Although the fossil record of propatagium is still patchy, presence of this soft structure has been recently documented in Microraptor (see Xu et al. 2003), Anchiornis (see ), Archaeopteryx (Martin and Lim 2005), and Enantiornithes (e.g., Noguerornis; Chiappe and Lacasa Ruiz 2002). Moreover, all known averaptorans (e.g. ...
Chapter
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All maniraptorans are closer to Neornithes than to Oviraptor.
... Conversely, in CAGS−IG−04− CM−007, the proximal tarsals are fused to the distal tibia, and the distal tarsals to the proximal surfaces of the metatarsals. Elements in common between CAGS−IG−04−CM−007 and Noguerornis gonzalezi (Chiappe and Lacasa−Ruiz 2002) consist only of a partial, questionably identified tibia in the latter, obviating comparison between the two. Zhang and Zhou (2000) reported Protopteryx fengnin− gensis as a basal enantiornithine. ...
Article
Full-text available
Although recent discoveries from Lower Cretaceous sediments in northeastern China have greatly improved our understanding of the initial stages of avian diversification in eastern Asia, the early evolution of Aves elsewhere on the continent remains poorly understood. In 2004, a collaborative field effort directed by personnel from the Chinese Academy of Geological Sciences and Carnegie Museum of Natural History recovered multiple partial to nearly complete avian skeletons from outcrops of the Lower Cretaceous Xiagou Formation exposed in the Changma Basin of northwestern Gansu Province, China. Here we describe a thrush-sized partial skeleton comprised of a fragmentary pelvic girdle and largely complete hind limbs. A phylogenetic analysis of 20 avian ingroup taxa and 169 anatomical characters places the specimen in Enantiomithes, and within that clade, in Enenantiomithes. When coupled with additional recent discoveries from the Changma Basin, the new skeleton improves our understanding of early avian evolution and diversification in central Asia.
... 62, n.º 1, 219-240, enero-diciembre 2006. ISSN: 0367-0449 Dinosaurios de la Península Ibérica 229 Lacasa-Ruiz, 2002) y un ejemplar juvenil de gran tamaño, al que no se asignó una denominación específica atendiendo a su inmadurez (Sanz et al., 1997), pero que, dado que sobrepasa largamente en talla a la mayor parte del resto de los ejemplares ibéricos, no parece corresponder a lo que se espera de los estadios ontogenéticos tempranos de las formas conocidas hasta el momento. Las últimas faunas del Cretácico Inferior ibérico corresponden al registro del Aptiense inferior que tiene una buena representación en los niveles de la Formación Arcillas Morella en la Comarca de Els Ports (Castellón). ...
Article
Body fossils of the Iberian Peninsula dinosaurs are very relevant for the knowledge of several aspects of the evolutionary history of the group, and, in addition, for the interpretation of the distribution of many of its components, due to the geographic situation of the Iberian Peninsula. Almost all of the groups of dinosaurs are represented in the Iberian Peninsula record: ornithopods, thyreophorans, theropods and sauropods. These groups are present, mainly, in the transit Jurassic-Cretaceous (Kimmeridigian-Berriasian), the upper part of the Lower Cretaceous (Barremian-Aptian) and in the end of the Upper Cretaceous (Campanian-Masstrichtian). Ornithischian dinosaurs are represented by thyreophorans such as the stegosaurians Dacentrurus and Stegosaurus, the ankylosaurs Dracopelta, Polacanthus and Struthiosaurus, and ornithopods like hypsilophodontids, basal iguanodontians (Rhabdodori), dryosaurids, camptosaurids (Draconyx and Camptosaurus), iguanodontids (Iguanodon) and hadrosaurids (Pararnabdodon). Some Incertae sedis and taxa in process of description are present too. Sauropods are represented by taxa related to Neosauropoda (Lourinhasaurus, Dinheirosaurus, Galveosaurus-and Losillasaurus) and titanosauriforms (Aragosaurus, Lusotitan and Lirainosaurus). In addition, new forms are still in description, like the sauropods of Riodeva (Teruel), Penarroya de Tastavins (Teruel) and Morella (Castellón). Theropods are represented by the ceratosaurian Ceratosaurus, the spinosauroid Torvosaurus, the carnosaurs Lourinhanosaurus and Allosaurus, the tyrannosaurid Aviatyrannis, the ornithomimosaur Pelecanimimus, and the avian-theropods Iberomesornis, Concornis, Eoalulavis and Noguerornis. Nevertheless, theropods diversity is more abundant as it shows the great variability of teeth morphotypes identified.
Article
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Despite a wealth of fossils of Mesozoic birds revealing evidence of plumage and other soft-tissue structures, the epidermal and dermal anatomy of their wing's patagia remain largely unknown. We describe a distal forelimb of an enantiornithine bird from the Lower Cretaceous limestones of Las Hoyas, Spain, which reveals the overall morphology of the integument of the wing and other connective structures associated with the insertion of flight feathers. The integumentary anatomy, and myological and arthrological organization of the new fossil is remarkably similar to that of modern birds, in which a system of small muscles, tendons and ligaments attaches to the follicles of the remigial feathers and maintains the functional integrity of the wing during flight. The new fossil documents the oldest known occurrence of connective tissues in association with the flight feathers of birds. Furthermore, the presence of an essentially modern connective arrangement in the wing of enantiornithines supports the interpretation of these primitive birds as competent fliers.