ISSN 00310301, Paleontological Journal, 2014, Vol. 48, No. 4, pp. 414–425. © Pleiades Publishing, Ltd., 2014. Original Russian Text © V.R. Alifanov, S.V. Saveliev, 2014, published in Paleontologicheskii Zhurnal, 2014, No. 4, pp. 72–82.
Two New Ornithischian Dinosaurs (Hypsilophodontia, Ornithopoda) from the Late Jurassic of Russia V. R. Alifanova and S. V. Savelievb a
Borissiak Paleontological Institute, Russian Academy of Sciences, Profsoyuznaya ul. 123, Moscow, 117997 Russia email:
[email protected] bScientific Research Institute of Human Morphology, Russian Academy of Medical Sciences, ul. Tsyurupy 3, Moscow, 117418 Russia email:
[email protected] Received March 03, 2013
Abstract—Two new dinosaurs, Kulindapteryx ukureica gen. et sp. nov. (Jeholosauridae) and Daurosaurus olo vus gen. et sp. nov. (Hypsilophodontidae) from the Ukureisk Formation (?Tithonian, Upper Jurassic) of the Kulinda locality in Transbaikalia (Russia) are described and assigned to Ornithopoda (Ornithischia). The ori gin and homology of the socalled obturator process of the ischium of Ornithopoda and Theropoda are dis cussed. The families Jeholosauridae and Hypsilophodontidae as well as Lesothosauridae are considered to belong to the infraorder Hypsilophodontia (Ornithopoda, Ornithischia). It is shown that hypsilophodontians had skin scales divided into bristles. Keywords: Jeholosauridae, Hypsilophodontidae, Hypsilophodontia, Ornithopoda, Ornithischia, Dinosauria, Tithonian, Upper Jurassic, Transbaikalia, Russia DOI: 10.1134/S0031030114040029
INTRODUCTION Most of the Late Jurassic dinosaur localities are recorded in North America and Western Europe. In other continents, they are scarce and contain isolated specimens, particularly those identified to species or genus. In Asia, the majority of known forms come from the first half of the Late Jurassic. The upper part of the Shaximiao Formation (Oxfordian), which is exposed in southern China (Sichuan), has yielded basal sauropods (Mamenchisaurus, Omeisaurus), allo sauroid theropods (Yangchuanosaurus, Sinraptor), an ornithopod (Yandusaurus), and stegosaurs (Tuojian gosaurus, Chungkingosaurus, Chialingosaurus). Some forms (Mamenchisaurus, Omeisaurus) are also known from the lower part of the same formation dated Mid dle Jurassic (Weishampel et al., 2004) and some (Mamenchisaurus, Sinraptor) are also observed in the dinosaur assemblage from the upper part of the Shishugou Formations (Oxfordian) of the Wucaiwan locality (XinjiangUyghur Autonomous Region). Wucaiwan has yielded a number of forms, such as Haplocheirus (?Coeluridae: Alifanov and Saveliev, 2011), Zoulong (Coeluridae), and Yinlong (?Protocer atopidae: Alifanov, 2012a). The diversity of Asiatic dinosaurs from the second half of the Late Jurassic is relatively poorly known, although it is judged by specimens from China. They include the sauropod Euchelopus (Shandong) and ornithischian dinosaurs Xuanhuaceratops (Hebei) and
Chaoyangsaurus (Liaoning). They are represented by fragmentary materials and usually considered to be related to horned dinosaurs, sometimes assigned to the family Chaoyangsauridae (Zhao et al., 2006). The type genus of the last group comes from the Tuchengzi For mation, which underlies the Jehol Group. A feathered theropod, Anchiornis, is known in Liaoning from the even more ancient Tiaojishan Formation (161– 151 Ma), which corresponds in age the first half of the Late Jurassic (or, possibly, its end) (Troodontidae: Hu et al., 2009). Kulinda is the first Russian and northernmost Asi atic locality of Late Jurassic dinosaurs. It was discov ered in the Transbaikalian Region in 2010; in 2011, it was investigated by a joint expedition of the Institute of Natural Resources, Ecology, and Cryology of the Rus sian Academy of Sciences and Borissiak Paleontolog ical Institute of the Russian Academy of Sciences. Field works have shown that specimens from the new locality belong to relatively smallsized forms of Theropoda and Ornithischia. Dinosaur remains are confined to narrow interbeds of silty tufa sandstones and tufa siltstones of the Uku reisk Formation, which are up to 100 m thick in the area of the locality. The formation is lacustrine in gen esis. The bones are frequently isolated; rarely, there are groups of two, three, or more elements buried together. In some specimens, enclosing rocks show imprints of skin derivatives, observed separately or
414
TWO NEW ORNITHISCHIAN DINOSAURS (HYPSILOPHODONTIA, ORNITHOPODA)
along with bone fossils. The history of the discovery of the locality, floral and invertebrate remains accompa nying dinosaurs, and dating of the Ukureisk Forma tion have been considered in the previous studies (Ali fanov, 2012b, 2014; Alifanov and Sinitsa, 2013). Based on paleoentomological data, it is tentatively dated Tithonian. The present study provides results of preliminary examination of ornithischian remains from the new locality, which are assigned to Ornithopoda, one of the most ancient and abundant group of Ornithischia. For a long time, ornithopods were considered to be ancestral to other ornithischian dinosaurs because of the idea of bipedalism of all its members. In the 1980s, a revision of early concepts of ornithischian evolution gave rise to new hypotheses for relationships, the most popular of which implies close phylogenetic relation ships of ornithopods and Marginocephalia (Ceratop sia and Pachycephalosauria). Excluding the presently rejected attempts to assign the problematic family Heterodontosauridae to ornithopods (Sereno, 1999; Norman et al., 2004), as a result of classification, true ornithopod dinosaurs were divided into two stems (infraorders), the Hypsilophodontia and Iguanodon tia (Sereno, 1986). The Iguanodontia, which comprise traditional families, such as Iguanodontidae and Hadrosauridae, are regarded as the most advanced ornithopods. They have opisthocoelous cervical and some thoracic verte brae, rather specific structure of the manus, with reduced number of phalanges in digit I (down to com plete reduction), four phalanges in digit V, which is isolated from digits II–IV, and some other characters. The monophyly of Early Cretaceous Iguanodontidae has recently been put in doubt, because some of the most progressive members of this group were shown to be phylogenetically close to Late Cretaceous Hadro sauridae. Relationships of certain forms, such as Camptosau rus (Late Jurassic of North America and Europe), Dryosaurus (Late Jurassic of Africa and North Amer ica), Tenontosaurus (Early Cretaceous of North Amer ica), and Zalmoxes (Late Cretaceous of Europe) are questionable. They are generally archaic and advanced in particular characters towards Iguanodontia, which is considered in modern works to be close to all of them (sometimes as separate families). The family Hypsilophodontidae is the central taxon of Hypsilophodontia. It was widespread in the Cretaceous. The fact that it was recorded in the Lower Cretaceous of Australia suggest that this group could have emerged in the Triassic of Pangea, when global distribution was possible. The family apparently includes certain species from the Middle Jurassic (lower part of the Shaximiao Formation) of China, of which Agilisaurus louderbacki and Hexinlusaurus mul tidens are represented by relatively complete speci mens and particularly thoroughly investigated, and PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
415
also Strombergia dangershoeki from the Lower Jurassic (upper part of the Elliot Formation) of South Africa. In the last decades, the Hypsilophodontidae have been investigated following two approaches. Initially, it was commonly accepted that this group is phyloge netically integral (Sereno, 1986; Sues and Norman, 1990; Weishampel and Heinrich, 1992; Sues, 1997). At present, it is usually regarded as nonmonophyletic and even some of its members are believed to be basal to different taxa of Ornithischia (Butler et al., 2008, 2011; Makovicky et al., 2011; Han et al., 2012). A sim ilar point of view was proposed by Galton (e.g., 1972, 1973, 1974). Note that, in our opinion, doubts con cerning the monophyly of Hypsilophodontidae are not supported by firm facts of their relationships with other groups. Modern works lack comments on the patterns of changes such a feature of ornithopods as the obturator process of the ischium, which, in opin ion of Santa Luca (1980), is the only reliable synapo morphy of this group. The obturator process of the ischium has previously been regarded as an archaic character based on the idea that Ornithopoda is ancestral to other Ornithis chia. At the present stage, this morphological structure is regarded as a synapomorphy based on the logical economy of this concept compared to the alternative, i.e., the loss of this process in the majority of ornithis chians (Maryanska and Osmólska, 1985). The origin and history of this structure remains mysterious and modern phylogenetic schemes allow the opportunity that it developed independently and repeated. It is interesting that, in theropods, the formation of the obturator process is determined by the opening of the internal contour of the obturator foramen (fenes tra) combined with the presence of the thyroid fenes tra, which is rather characteristic of this group. How ever, the ischia of ornithopods have neither obturator foramen nor thyroid fenestra. They are also absent in ornithischian dinosaurs as a whole. In this case, the upper edge of the obturator processes may only be connected to the border of the caudal pelvic exit (Fig. 1a) and its lower edge, with the border of the fenestra or an underossifying structure on the elon gated and transversely expanded ischial symphysis (Fig. 1b). The above explanation puts in doubt the homology of the obturator process of the ischium of theropods and ornithopods. The hypothesis also allows that, in advanced ornithopod, such as for example, Iguan odontidae and Hadrosauridae, the “obturator” pro cesses turned cranially. It should be emphasized that the formation of the “obturator” process was preceded by elongation of the ischial symphysis. This is probably responsible for the presence of an angular projection on the ischia. The last structure has recently been rec ognized in some hypsilophodontians (see below). It is noteworthy that the angular projection, like the “obtu rator” process, is a synapomorphy. The main differ
416
ALIFANOV, SAVELIEV
Ani Po
Smi
(a)
Fs
(b)
Fig. 1. Hypothesis for the origin of the “obturator” process in Ornithopoda: (a) vertically lengthened symphysis and transverse expansion of the ischia in Lesothosaurus diag nosticus (after Butler, 2005, textfig. 4), (b) formation of medially directed obturator processes on the extended symphysis of the ischia by fenestration of the last. Designa tions: (Ani) angular projection, (Fs) symphyseal fenestra, (Po) obturator process, (Smi) ischial symphysis.
ence of the two above conditions is the absence or presence of a fenestra on the ischial symphysis. The idea of the common origin of the obturator process and angular projection of the ischium initiates the discussion of relationships between hypsiloph odontians and Lesothosaurus diagnosticus, a problem atic species extremely important from the point of view of the evolution of ornithischian dinosaurs. Relationships of Lesothosaurus diagnosticus, which comes from the same beds as the abovementioned Strombergia dangershoeki, have been considering from the point of original description of this species. It was initially assigned to the family Fabrosauridae, regarded by Thulborn (1971) as archaic and, in fact, heterogeneous, with the questionable validity of the type genus (Sereno, 1991). Subsequently, it was pro posed that it may be related to ornithopods (Maryanska and Osmólska, 1978; Norman, 1984; Cooper, 1985) and positioned at the base of all orni thischian dinosaurs (Sereno, 1986). The last point of view is most widely accepted, although alternative hypotheses have also been developed, presuming that L. diagnosticus is probably basal to Neornithischia (Euornithopoda, Marginocephalia; Butler, 2005) or Thyreophora (Butler et al., 2008). An opportunity of assignment of L. diagnosticus along with Eocursor par
vus from the Upper Triassic (lower part of the Elliot Formation) South Africa (Butler et al., 2007; Butler, 2010) to the family Lesothosauridae deserves special remarks. The relationship of the two forms is sup ported by the fact that they share the angular projec tion of the ischium, mandibular fenestrae, and large obturator foramen in the pubes. The Lesothosauridae are characterized by archaic characters, such as con nection between the squamosals and quadratojugals, large preorbital fenestra, relatively small premaxilla, short preacetabular processes of the pubes, etc. The idea of relationships between Lesothosauridae and Hypsilophodontidae is supported by a set of archaic and advanced characters. In addition to the extended symphysis of the ischium, the latter include the considerably shortened femora compared to tibio tarsi. This feature of dinosaurs and reptiles as a whole is secondary. In Ornithischia, it develops indepen dently in a number of stems, including Ornithopoda, and usually correlates with bipedal locomotion. The assumption of the basal position of forms with the above disproportion in the sizes of femora and tibio tarsi among ornithischian dinosaurs looks highly improbable. A new topic in the discussion of the evolution of Ornithopoda is introduction in their system of the family Jeholosauridae (Han et al., 2012), the type genus of which Jeholosaurus (J. shangyuanensis) comes from the Early Cretaceous of the Yixian For mation in China (Liaoning). At present, this group is difficult to characterize morphologically; however, the fact that it exists is corroborated by the data on the Late Jurassic of Transbaikalia, where it is also present. Taking into account the structure of pelvic bones (Fig. 2), the family Jeholosauridae looks intermediate between Lesothosauridae (Fig. 2a) and Hypsiloph odontidae (Figs. 2d–2f). Note that for Jeholosauridae (Figs. 2b, 2c), like Lesothosauridae, has an angular projection of the ischium. Figure 3 displays relation ships of the ornithopod families in question, which involves the taxon Hypsilophodontia, which escaped the attention of researchers. The taxonomic section of the present study contains an expanded diagnosis of this taxon represented as a set of archaic and advanced characters. The true Hypsilophodontidae probably consist of two subgroups, which could have been formed in Cen tral Asia and the western part of Laurasia separated by the Turgai Sea. As is well known, the biogeographical isolation which occurred in the Late Jurassic or even earlier resulted in an increase in endemism of tetrapod assemblages of the two territories. It probably contrib uted to the diversity of hypsilophodontids, although this conclusion requires additional fact material. Nev ertheless, West Laurasian and Asian hypsilophodon tids differ in certain cranial features. For example, Hypsilophodon foxii known by a complete skull from the Lower Cretaceous of Europe has a foramen at the junction of the maxilla and premaxilla, whereas Agili PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
TWO NEW ORNITHISCHIAN DINOSAURS (HYPSILOPHODONTIA, ORNITHOPODA)
(a)
(b)
(c)
(d)
(e)
(f)
417
Fig. 2. Reconstruction of the pelvis (lateral view) in different groups of Hypsilophodontia: (a) Lesothosaurus diagnosticus (after Sereno, 1991, textfigs. 9, 10); (b) Jeholosaurus shangyuanensis (after Han et al., 2012, textfigs. 6, 9); (c) Kulindapteryx ukureica gen. et sp. nov. (based on holotype PIN, no. 5434/25 and specimen PIN, no. 5434/41); (d) Daurosaurus olovus gen. et sp. nov. (based on holotype PIN, no. 5434/1 and specimens PIN, nos. 5434/24 and 5434/40); (e) Hexinlusaurus multidens (after Barrett et al., 2005, textfig. 4a); (f) Hypsilophodon foxii (after Galton, 1974, textfig. 46). Dotted line shows bones the are tentatively referred to respective species.
saurus louderbacki from the Middle Jurassic of China, which was also described based on a complete skull, it is absent. The significance of this character is empha sized by the fact that it is the major diagnostic charac ter of the horned dinosaur family Bagaceratopidae (Neoceratopsia), distinguishing it from all Ceratopsia (Alifanov, 2003, 2005, 2008). It is also noteworthy that A. louderbacki has a characteristic heterodonty of the lower teeth and two supraorbitals. The anterior supraorbital is one of two anlagen of the prefrontal (in pachycephalosaurs and horned dinosaurs of the family Ceratopidae, these bones can be fused with true prefrontals); and the posterior supraorbital is homologous to the postfrontal (Alifanov, 2012a), which is generally believed to be initially lost in orni thischian dinosaurs. PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
Hypsilophodontia Lesothosauridae
Jeholosauridae Hypsilophodontidae
Fig. 3. Hypothesis for phylogenetic relationships of the families of Hypsilophodontia.
418
ALIFANOV, SAVELIEV
The above data cast doubt on the relationship of Jeholosauridae with the recently described Late Cre taceous Haya griva from Mongolia (Makovicky et al., 2011). Judging from the presence of a foramen in the suture between the premaxilla and maxilla, as in Hyp silophodon foxii, it is possible that the Late Cretaceous Asian species belongs to the Euroamerican branch of hypsilophodontids. The last group could have pene trated into Asia through the Bering Bridge, which exited at the Early–Late Cretaceous boundary (Kalandadze and Rautian, 1992, 1997; Alifanov, 2000). The family Jeholosauridae is considered to include one more form from the Yixian Formation, Changchunsaurus parvus (Zan et al., 2005). It is repre sented by fragmentary materials, so that it is only ten tatively considered to be related to Jeholosaurus shangyuanensis (Butler et al., 2011), although this conclusion is more reliable than in the case of H. griva. The absence of Jeholosauridae and possibly the Asiatic branch of Hypsilophodontidae in the Late Cretaceous of Central Asia (if it were not caused by taphonomic factors) possibly results from competition with horned dinosaurs (Ceratopsia). The last group became widespread in the Early Cretaceous and con tinued throughout most of the Late Cretaceous. The data from Kulinda concern an earlier episode of dino saurian evolution and suggest that, during the second half of the Late Jurassic, the ornithischian dinosaur assemblages of Transbaikalia, or even the entire Cen tral Asia were dominated by the ornithopod taxon Hypsilophodontia.
losauridae Han et al., 2012, Late Jurassic–Early Cre taceous of Asia. R e m a r k s. The scale of tuberculate type, which is known in the families Iguanodontidae and Hadrosau ridae, was previously reconstructed for all Ornitho poda. However, the data of the present study show that hypsilophodontians had bristlelike skin derivatives. It is supposed that this feature, along with the others listed in the diagnosis, distinguish them from Iguan odontia. Family Jeholosauridae Han, Barrett, Butler et Xu, 2012
Ty p e g e n u s. Jeholosaurus Xu et al., 2000. D i a g n o s i s. Quadratojugal lacking contact with squamosal. Jugals not participating in border of preor bital fenestrae. Mandibular fenestrae in lower jaw rami not expressed. Ilia longitudinally extended. Preace tabular process of pubes elongated. Ischia lacing obtu rator process and having angular projection. G e n e r i c c o m p o s i t i o n. Genera Jeholosau rus Xu et al., 2000, Changchunsaurus Zan et al., 2005, Early Cretaceous of northeastern China; Kulindap teryx gen. nov., Late Jurassic of Transbaikalia. C o m p a r i s o n. The family Jeholosauridae dif fers from Lesothosauridae in the loss of contact between the quadratojugal and squamosal, the jugals not contributing to the formation of the border of the preorbital fenestrae, the absence of mandibular fenes trae, the elongated ilia and preacetabular process of the pubes and from Hypsilophodontidae in the absence of the obturator process of the ischia.
SYSTEMATIC PALEONTOLOGY Superorder Dinosauria
Genus Kulindapteryx Alifanov et Saveliev, gen. nov.
Order Ornithischia
E t y m o l o g y. From the Kulinda locality and the Greek pteryx (wing). Ty p e s p e c i e s. Kulindapteryx ukureica sp. nov. D i a g n o s i s. Preacetabular process of pubes con ical. Obturator foramen of these bones relatively large. Before division into pubic and iliac processes, ischia strongly narrowed. Axes of pubioiliac part and distal shaft positioned at angle of 30°. Ischia forming elon gated pubic process and large angular projection located approximately at level of distal part of second quarter of bone length. At level of angular projection apex, these bones very wide, gradually and insignifi cantly narrowing in distal direction. S p e c i e s c o m p o s i t i o n. Type species. C o m p a r i s o n. The new genus differs from Jeho losaurus Xu et al., 2000 in the ischium structure, with a strong narrowing before division into the pubic and iliac processes, the large angular projection, very wide distal part, large angle between the axes of the pubioil iac part and distal shaft, the displacement of the angu lar projection tip towards the distal part of the second quarter of the bone length, and in the elongated pubic process.
Suborder Ornithopoda I n f r a o r d e r Hypsilophodontia
D i a g n o s i s. Preorbital fenestrae expressed, often large. Supraoccipitals forming border of fora men magnum. Premaxillae toothed. Nasals and max illae in contact. Frontals longer than, or equal to, nasals. Preacetabular process of pubes rodlike. Ace tabular edge of these bones curving towards acetabu lum and not divided into iliac and ischiadic rami. Descending ramus of pubes approximately as long as ischia. Scapulae not longer than humeri. In manus, digit III consisting of four phalanges and digit V including at most three phalanges. Femora always shorter than tibiotarsi. Digit I of foot usually enlarged. Integument having bristlelike appendages. C o m p o s i t i o n. Families Lesothosauridae Hal stead et Halstead, 1981, Late Triassic–Early Jurassic of South Africa; Hypsilophodontidae Dollo, 1882, Early Jurassic of South Africa, Middle Jurassic–Late Cretaceous of Asia, Late Cretaceous of North Amer ica, Early Cretaceous of Europe and Australia; Jeho
PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
TWO NEW ORNITHISCHIAN DINOSAURS (HYPSILOPHODONTIA, ORNITHOPODA)
R e m a r k s. It is impossible to compare Kulindap teryx gen. nov. with Changchunsaurus Zan et al., 2005, because available specimens lack comparable ele ments of the holotypes. It is also impossible to com pare Kulindapteryx gen. nov. with Jeholosaurus Xu et al., 2000 in the pubic structure, since respective data on the latter form are presently absent. Kulindapteryx ukureica Alifanov et Saveliev, sp. nov. Plate 10, figs. 1 and 2
E t y m o l o g y. From the Ukureisk Formation. H o l o t y p e. PIN, no. 5434/25 (a, b), fragmen tary vertebra, ischium and pubis on matrix; Trans baikalia, Chernyshevskii District, Orlovskaya Depres sion, Kulinda locality; Upper Jurassic, ?Tithonian, Ukureisk Formation. D e s c r i p t i o n (Fig. 2c). It is difficult to judge the structure of the vertebra represented in the type material by a fragment; the only evident thing is that its neural spine is rather high. This is presumably an anterior caudal vertebra. The preacetabular process of the pubes is arched (its dorsal edge is concave and the ventral edge is con vex). The ilioischiadic process of the pubes is massive and probably had a transverse expansion. The obtura tor foramen of pubes was closed incompletely and its border was partly formed by the pubic process of the ischia. The descending process of the pubes is only represented by a thin arched base (the curvature could have been formed postmorten). The margins of the pubic and iliac processes of the ischium are round at the end and the part of the ace tabulum bordered by these processes covers approxi mately onethird of its diameter. Before division into the pubic and iliac processes, the ischium is narrowed. The narrowed area crosses the crest directed from the proximal edge of the angular projection base to the posterior edge of the iliac process base. The crest marked above is evidence that, during the animal’s life, the articular processes and shafts of the ischium could have been positioned in different planes. The distal part of the ischia lacks narrowings and projec tions; it is slightly narrowed and rounded terminally. M e a s u r e m e n t s of the holotype in mm. Isch ium: total length, 104; width at the level of the angular projection, 14; width in the narrowest part, 6; distance from the edge of the pubic process to the apex of the angular projection, 47; distance from the apex of the angular projection to the distal end, 63; pubis: length and base height of the preacetabular process, 33 and 14; longitudinal diameter of the obturator foramen, 7; height of the ilioischiadic process base, 11; width of the descending ramus base, 2. M a t e r i a l. Holotype. Family Hypsilophodontidae Dollo, 1882
Ty p e g e n u s. Hypsilophodon Huxley, 1869. PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
419
D i a g n o s i s. Quadratojugal lacking contact with squamosal. Jugals not participating in formation of preorbital fenestrae. Mandibular fenestrae absent. Preacetabular process of pubis elongated. Ilia extended longitudinally. Obturator process of ischia present. G e n e r i c c o m p o s i t i o n. Genera Hypsiloph odon Huxley, 1869, Early Cretaceous of Europe; Strombergia Butler, 2005, Early Jurassic of South Africa; Othnielia Galton, 1977, Late Jurassic of North America; Zephyrosaurus Sues, 1980, Bugenasaura Galton, 1995, Orodromeus Horner et Weishampel, 1988, Parksosaurus Sternberg, 1937, Thescelosaurus Gilmore, 1913, Late Cretaceous of North America; Anabisetia Coria et Calvo, 1998, Notohypsilophodon Martinez, 1998, Late Cretaceous of South America; Atlascopcosaurus Rich et Rich, 1989, Fulgurotherium Huene, 1932, Leaellynasaura Rich et Rich, 1989, Qantassaurus Rich et VickersRich, 1999, early Creta ceous of Australia; Agilisaurus Peng, 1990, Hexinlus aurus Butler et al., 2005, Middle Jurassic of China; Yandusaurus He, 1979, Late Jurassic of China; Dauro saurus gen. nov., Late Jurassic of Transbaikalia; Haya Han et al., 2012, Late Cretaceous of Mongolia. C o m p a r i s o n. The family Hypsilophodontidae differs from other Hypsilophodontia in the presence of an obturator process of the ischium. It additionally differs from Lesothosauridae in the loss of connection between the quadratojugals and squamosals, the absence of jugals in the border of the preorbital fenes trae, the absence of mandibular fenestrae, the elon gated ilia, and in the preacetabular process of the pubes. Genus Daurosaurus Alifanov et Saveliev, gen. nov.
E t y m o l o g y. From Dauria, ancient Russian name of western areas of Transbaikalia and eastern areas of the Amur Region, and the Greek sauros (lizard). Ty p e s p e c i e s. Daurosaurus olovus sp. nov. D i a g n o s i s. Apex of obturator process of ischia round and its base very wide. Apical part of last process located at level of middle of second quarter of bone. Shaft of ischia distinctly arched. Iliac and pubic pro cesses of ischia wide and area of their connection extensive. Iliac process of these bones larger than pubic process. S p e c i e s c o m p o s i t i o n. Type species. C o m p a r i s o n. Daurosaurus gen. nov. differs from other forms of the family in the extended base of the obturator processes, the wide pubic and iliac pro cesses of the ischia, and in the extensive zone of con tact between the two processes. The new genus differs from the majority of members of the family in the position of the apical part of the obturator process, which is approximately at the level of the second quar ter of the bone, the distinctly arched shaft of the ischia, and in the larger iliac process of this bone compared to the pubic process.
420
ALIFANOV, SAVELIEV Plate 10
1
2
3
4
5
PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
TWO NEW ORNITHISCHIAN DINOSAURS (HYPSILOPHODONTIA, ORNITHOPODA) Daurosaurus olovus Alifanov et Saveliev, sp. nov. Plate 10, figs. 3 and 4
E t y m o l o g y. From the Olov River flowing in the vicinity of the locality. H o l o t y p e. PIN, no. 5434/1 (a, b), imprint (and its counterpart) on a rock sample of an ischium (frag ment), ilium, femur, and tibia; Transbaikalian Region, Chernyshevskii District, Orlovskaya Depression, Kulinda locality; Upper Jurassic, ?Tithonian, Ukure isk Formation. D e s c r i p t i o n (Fig. 2d). The ilium of the holo type is preserved more completely than in other spec imens. Its dorsal margin is gently arched. The cranial process of this bone is relatively thin, sometimes has hardly discernible angular projection in the middle part of its dorsal margin (recognized in the holotype). The notch between it and pubic process is Jshaped. The caudal process narrows slightly posteriorly. Its base is approximately twice as high as the cranial pro cess base. The distance between the anterior margin of the pubic process and posterior edge of the ischiadic process is onethird of the total bone length. In addi tion, a Vshaped margin of the internal wall of the ace tabular foramen is formed between them. The counterpart of the holotype shows a proximal fragment of the ischium, which is almost identical in structure to that of specimen PIN, no. 5434/40 (based on which characters of the ischium are included in the generic diagnosis). For the ischia, it is possible to add that the pubic process base is somewhat wider than the iliac process. The region of ischium narrowing has a crest directed from the margin of the angular projection to the pos terior margin of the iliac process base of the bone, as in Kulindapteryx ukureica gen. et sp. nov. However, in this case, the crest is weak, which is probably connected with the small angle between the plane of articular processes of the bone and its shaft. The femur is straight. The greater trochanter is located at the level of the upper edge of the femoral head and separated from it by a superficial notch. The femoral head is large and its axis is positioned close to a right angle to the bone shaft axis. The fourth tro chanter is located at the level of the second quarter of the femoral length. The distal condyles of the last bone are deeply separated; in front view, the incisure between them is Vshaped. Other structures are impossible to recognize because of poor preservation.
421
The tibial epiphyses are very wide. These bones are 1.25 as long as the femur. Other structural details of the tibia and fibula of the holotype are indiscernible. M e a s u r e m e n t s in mm. Holotype: iliac length, 100; iliac height, 27; width of the proximal part of the ischium, 26; femoral length, 120; its proximal and dis tal width, 30 and 20; tibial length, 155; width of its proximal and distal ends, 25 and 20; specimen PIN; no. 5434/40; ischium: total length, 90; width at the level of the obturator process, 10; width of the proximal part, 26; width in the narrowest part, 7; distance from the pubic process edge to obturator process tip, 40; distance from the obturator process tip to distal bone edge, 53. M a t e r i a l. In addition to the holotype, speci mens PIN, nos. 5434/17, 5434/20 (a, b), 5434/37 (a, b), ilia; specimens PIN, nos. 5434/39 (a, b), 5434/40, 5434/43, ischia. DISCUSSION The series of specimens from the Kulinda locality contains many isolated elements of the ornithopod skeleton, which can formally be determined only as Hypsilophodontia fam. indet. Some of them are con sidered in this section of the paper as important mate rials supplementing the few type specimens. Some specimens are interesting from the point of view of reconstruction of the appearance of two species described above and hypsilophodontians as a whole. For further consideration, it is required to pay attention to the prevalence in the collection from Kulinda of Daurosaurus olovus gen. et sp. nov. This conclusion is based primarily on the series of ischia, which are identical to the holotype. The collection also contains a series of rather uniform ilia, similar in morphology to that of the holotype of Daurosaurus olovus gen. et sp. nov. An important point is complete absence of reliable data indicating the presence in Kulinda of a third hypsilophodontians species. Under this conditions, the find of an ilium imprint (specimen PIN, no. 5434/41; Pl. 12, fig. 1) which dif fers from the majority of others referred here to Dau rosaurus olovus gen. et sp. nov. is of interest. This bone is distinguished by the rather low height and sigmoid curvature of the upper edge. If these characters do not represent individual or sexual variations, the specimen in question probably belongs to a different hypsiloph odontian species from the Kulinda locality, that is, Kulindapteryx ukureica gen. et sp. nov.
Explanation of Plate 10 All specimens come from the Kulinda locality, Transbaikalian Region, Russia; Upper Jurassic, ?Tithonian, Ukureisk Formation. Figs. 1 and 2. Kulindapteryx ukureica gen. et sp. nov., holotype PIN, no. 5434/25a: (1) pubis, (2) ischium. Figs. 3 and 4. Daurosaurus olovus gen. et sp. nov.: (3) holotype PIN, no. 5434/1a, ilium, femur, and tibia; (4) specimen PIN, no. 5434/40, ischium. Fig. 5. Hypsilophodontia fam. indet., specimen PIN, no. 5434/24a, pubis. Scale bar, 30 mm. PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
422
ALIFANOV, SAVELIEV Plate 11
2
1
S
H R U
3
4
5
Explanation of Plate 11 All specimens come from the Kulinda locality, Transbaikalian Region, Russia; Upper Jurassic, ?Tithonian, Ukureisk Formation. Figs. 1–5. Skeletal bones and imprints of integument of Hypsilophodontia fam. indet.: (1) specimen PIN, no. 5434/41, ilium; (2) specimen PIN, no. 5434/19, dentary fragment with teeth; (3) specimen PIN, no. 5434/54, humerus and scapula; (4) speci men PIN, no. 5434/57a, humerus without proximal end and proximal parts of ulna and radius with imprints of scales and bristle like derivatives of skin on rock; (5) specimen PIN, no. 5434/56a, humerus and field with elongated bristlelike appendages on enclosing matter. Designations of bones: (H) humerus, (R) radius, (S) scapula, and (U) ulna. Scale bar, 30 mm. PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
TWO NEW ORNITHISCHIAN DINOSAURS (HYPSILOPHODONTIA, ORNITHOPODA)
423
(a)
(b)
Fig. 4. Reconstruction of body outlines in hypsilophodontians from the Kulinda locality (Transbaikalian Region, Russia; Upper Jurassic, ?Tithonian, Ukureisk Formation): (a) Kulindapteryx ukureica gen. et sp. nov. (Jeholosauridae); (b) Daurosaurus olovus gen. et sp. nov. (Hypsilophodontidae). White color shows the bones providing the basis for description of species; points designate skeletal elements that are tentatively referred to particular species.
Taking into account the prevalence in the collec tion from Kulinda of Daurosaurus olovus gen. et sp. nov., it is possible that isolated specimens considered below also belong to this species. One of them is a dentary fragment with a few teeth (specimen PIN, no. 5434/19; Pl. 11, fig. 2). They have spatulate crowns divided into several apices. The num ber of apices ranges from five in the anterior teeth to seven in the middle teeth and nine in the posterior teeth. The lateral apices are lower than the central one and decrease in height towards the edge. Between the apices, there is a relatively deep facet. The primary crest on the teeth is poorly developed. Another specimen of this kind (PIN, no. 5434/24; Pl. 10, fig. 5) is a pubis. It differs from the pubis of the holotype of Kulindapteryx ukureica gen. et sp. nov. (Pl. 10, fig. 1) in the rostrally relatively wider preace tabular process, the straight dorsal edge of this process, and in the shorter and narrower ilioischiadic process. Plate 11 (fig. 3) shows imprints of the right scapula and humerus (specimen PIN, no. 5434/54), which probably belong to one individual. This scapula is PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
slightly shorter than the humerus, which is typical of hypsilophodontians. Its dorsal part is distinctly wid ened, the acromion is very short, and the supraglenoid is poorly pronounced and only slightly expanded. In the proportions of anatomical details, the scapulae of hypsilophodontians from Kulinda resemble Hexinlus aurus multidens from the Middle Jurassic of China. The deltopectoral crest of the humerus is high, occu pies onethird of the bone extent. An incisure between it and the humeral head is absent. The humeral head is indiscernible in the specimen. Distally, the bone in question has two distinct condyles, one of which is slightly larger than the other. The humeral shape is typical for many hypsilophodontians and comparable in general proportions to some humeri from the type series of H. multidens. The humerus is also preserved in specimen PIN, no. 5435/57 (Pl. 11, fig. 4), along with the proximal ends of the radius and ulna. Because of disruption, it is impossible to recognize morphological details of the bones, except for the general habitus. In particular, it is possible to note that the ulna is naturally larger than
424
ALIFANOV, SAVELIEV
the radius and the humerus is morphologically identi cal to that of the previous specimen, but slightly larger. In contrast to the previous case, bones of the last spec imen are in association with integument remains pre served on the rock surface. Imprints of the integument in specimen PIN, no. 5435/57 are located near the humerus, mostly anterior (at the proximal end) and posterior to it and represented by derivatives of two types. Some of them look like oval platy scales and others are bristlelike structures. In the region of the posterior edge of the humerus of this specimen (Pl. 11, fig. 4), the “bristles” overlie the plates. However, some “bristles” seem to continue the plates. If this is the case, the “bristles” may result from either splitting or differentiated growth of the plates. Judging from the positions of the fields anterior and posterior to the humerus, the above integument type was regularly distributed on the fore limb surface and possibly the entire body. It is remark able that this specimen differs in the bristles length from the specimen considered below. Specimen PIN, no. 5435/56 (Pl. 11, fig. 5), which played certain role in the choice of the generic name of Kulindapteryx ukureica gen. et sp. nov., has long bris tlelike structures near forelimb bones (the humerus is preserved on the main imprint and, on the counter part, there is the radius) over a large area of the rock, as in wing imprints of fossil birds. The poor preservation of bones of the last specimen prevents even approximate taxonomic identification. However, on the assumption that two different lengths of bristlelike structures on the same bones correspond to two hypsilophodontians species, it is not improba ble that, in Kulinda, different hypsilophodontian spe cies were distinguished by the length of “bristles”. If this is the case, according to the prevalence in the locality of Daurosaurus olovus gen. et sp. nov. (see above) and judging from the proportions of specimens with bristlelike structures differing in length, it is pos sible to conclude that the last species had scales with bristles of the short type. Consequently, it should be proposed that Kulindapteryx ukureica gen. et sp. nov. had a long bristle type of integumental appendages. We are intended to discuss in more detail structural features of skin derivatives of hypsilophodontians from Kulinda in a separate publication. Figure 4 shows the bones of Kulindapteryx ukureica gen. et sp. nov. and Daurosaurus olovus gen. et sp. nov. described and discussed above and also interpretation of the outline of the two forms, taking into account the data on integumental remains. ACKNOWLEDGMENTS This study was supported by the Russian Founda tion for Basic Research (project no. 120500302) and Independent Nonprofit Organization, Institute of Biomedical Problems “Vertebrate Paleontology.”
REFERENCES Alifanov, V.R., Macrocephalosaurs and early evolutionary stages of lizards in Mongolia, Tr. Paleontol. Inst. Ross. Akad. Nauk, 2000, vol. 272, pp. 1–126. Alifanov, V.R., Two new dinosaurs of the infraorder Neo ceratopsia (Ornithischia) from the Upper Cretaceous of the Nemegt Depression, Mongolian People’s Republic, Paleontol. Zh., 2003, no. 5, pp. 77–88. Alifanov, V.R., Amazing horned dinosaurs, Priroda (Mos cow, Russ. Fed.), 2005, no. 10, pp. 58–69. Alifanov, V.R., The tiny horned dinosaur Gobiceratops minutus gen. et sp. nov. (Bagaceratopidae, Neoceratopsia) from the Upper Cretaceous of Mongolia, Paleontol. Zh., 2008, no. 6, pp. 49–60. Alifanov, V.R., Suborder Ornithischia, in Iskopaemye reptilii i ptitsy: Chast’ 2 (Fossil Reptiles and Birds: Part 2), Kuroch kin, E.N. and Lopatin, A.V., Eds., Moscow: GEOS, 2012a, pp. 241–309. Alifanov, V.R., Kulinda, the first Late Jurassic dinosaur locality in Russia, Priroda (Moscow, Russ. Fed.), 2012b, no. 3, pp. 53–54. Alifanov, V.R., On the discovery of Late Jurassic dinosaurs in Transbaikalia, Dokl. Akad. Nauk, 2014, vol. 455, no. 4, pp. 421–423. Alifanov, V.R. and Saveliev, S.V., Brain structure and neuro biology of alvarezsaurians (Dinosauria), exemplified by Ceratonykus oculatus (Parvicursoridae) from the Late Cre taceous of Mongolia, Paleontol. Zh., 2011, no. 2, pp. 61–69. Alifanov, V.R. and Sinitsa, S.M., “Park of the Jurassic period” in Transbaikalia, Nauka v Rossii, 2013, no. 1, pp. 16–22. Barrett, P.M., Butler, R.J., and Knoll, F., Smallbodied ornithischian dinosaurs from the Middle Jurassic of Sichuan, China, J. Vertebr. Paleontol., 2005, vol. 25, no. 4, pp. 823–834. Butler, R.J., The 'fabrosaurid' ornithischian dinosaurs of the Upper Elliot Formation (Lower Jurassic) of South Africa and Lesotho, Zool. J. Linn. Soc., 2005, vol. 145, no. 2, pp. 175–218. Butler, R.J., The anatomy of the basal ornithischian dino saur Eocursor parvus from the Lower Elliot Formation (Late Triassic) of South Africa, Zool. J. Linn. Soc., 2010, vol. 160, no. 4, pp. 648–684. Butler, R.J., Jin, L., Chen, J., and Godefroit, P., The post cranial osteology and phylogenetic position of the small ornithischian dinosaur Changchunsaurus parvus from the Quantou Formation (Cretaceous: Aptian–Cenomanian) of Jilin Province, northeastern China, Palaeontology, 2011, vol. 54, no. 3, pp. 667–683. Butler, R.J., Smith, R.M.H., and Norman, D.B., A primi tive ornithischian dinosaur from the Late Triassic of South Africa, and the early evolution and diversification of Orni thischia, Proc. Roy. Soc. B Biol. Sci., 2007, vol. 274, no. 1621, pp. 2041–2046. Butler, R.J., Upchurch, P., and Norman, D.B., The phy logeny of the ornithischian dinosaurs, J. Syst. Palaeontol., 2008, vol. 6, no. 1, pp. 1–40. Cooper, M.R., Revision of the ornithischian dinosaur Kan gnasaurus coetzeei Haughton, with a classification of the Ornithischia, Ann. S. Afr. Mus., 1985, vol. 95, pp. 281–317. PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
TWO NEW ORNITHISCHIAN DINOSAURS (HYPSILOPHODONTIA, ORNITHOPODA) Galton, P.M., Classification and evolution of ornithopod dinosaurs, Nature, 1972, vol. 239, no. 5373, pp. 464–466. Galton, P.M., Redescription of the skull and mandible of Parksosaurus from the Late Cretaceous with comments on the family Hypsilophodontidae (Ornithischia), Roy. Ontario Mus. Publ. Life Sci., 1973, no. 89, pp. 1–21. Galton, P.M., Notes on Thescelosaurus, a conservative ornithopod from the Upper Cretaceous of North America, with comments on ornithopod classification, J. Paleontol., 1974, vol. 48, no. 5, pp. 1048–1067. Han, F., Barrett, P.M., Butler, R.J., and Xu, X., Postcranial anatomy of Jeholosaurus shangyuanensis (Dinosauria, Ornithischia) from the Lower Cretaceous Yixian Formation of China, J. Vertebr. Paleontol., 2012, vol. 32, no. 6, pp. 1370–1395. Hu, D., Hou, L., Zhang, L., and Xu, X., A preArchaeop teryx troodontid theropod from China with long feathers on the metatarsus, Nature, 2009, vol. 461, no. 7264, pp. 640– 643. Kalandadze, N.N. and Rautian, A.S., The system of mam mals and historical zoogeography, Tr. Zool. Muz. Mosk. Gos. Univ., 1992, vol. 29 (Phylogenetics of Mammals, Ros solimo, O.L., Ed.), pp. 44–152. Kalandadze, N.N. and Rautian, A.S., Historical zoogeog raphy of terrestrial tetrapods and new method of global palaeogeographical reconstructions, Rec. Queen Victoria Mus., Art Gall. Launceston, 1997, no. 104 (Evolution of the Biosphere, Rozanov, A.Yu., VickersRich, P., and Tassel, C., Eds.), pp. 95–98. Makovicky, P.J., Kilbourne, B.M., Sadleir, R.W., et al., A new basal ornithopod (Dinosauria, Ornithischia) from the Late Cretaceous of Mongolia, J. Vertebr. Paleontol., 2011, vol. 31, no. 6, pp. 626–640. Maryan’ska, T. and Osmólska, H., On ornithischian phy logeny, Acta Palaeontol. Polon., 1985, vol. 30, nos. 3–4, pp. 137–150. Norman, D.B., A systematic reappraisal of the reptile order Ornithischia, in 3rd Symposium on Mesozoic Terrestrial Eco systems: Short Papers, Reif, W.E. and Westphal, F., Eds., Tübingen: Attempto Verlag, 1984, pp. 157–162.
PALEONTOLOGICAL JOURNAL
Vol. 48
No. 4
2014
425
Norman, D.B., Basal Iguanodontia, in The Dinosauria, 2nd ed., Weishampel, D.B., Dodson, P., and Osmólska, H., Eds., Berkeley–Los Angeles–London: Univ. California Press, 2004, pp. 413–437. Santa Luca, A.P., The postcranial skeleton of Heterodonto saurus tucki (Reptilia, Ornithischia) from the Stromberg of South Africa, Ann. S. Afr. Mus., 1980, vol. 79, no. 7, pp. 159–211. Sereno, P.C., Phylogeny of the birdhipped dinosaurs (order Ornithischia), Nat. Geogr. Res., 1986, vol. 2, no. 2, pp. 234–256. Sereno, P.C., Lesothosaurus, “fabrosaurids,” and the early evolution of Ornithischia, J. Vertebr. Paleontol., 1991, vol. 11, no. 2, pp. 168–197. Sereno, P.C., The evolution of dinosaurs, Science, 1999, vol. 284, no. 5423, pp. 2137–2147. Sues, H.D., Hypsilophodontidae, in Encyclopedia of Dino saurs, Currie, P.J. and Padian, K., Eds., San Diego: Acad. Press, 1997, pp. 356–358. Sues, H.D. and Norman, D.B., Hypsilophodontidae, Tenon tosaurus, Dryosauridae, in The Dinosauria, Weishampel, D.B., Dodson, P., and Osmólska, H., Eds., Berkeley–Los Ange les–London: Univ. California Press, 1990, pp. 498–509. Thulborn, R.A., Origins and evolution of ornithischian dinosaurs, Nature, 1971, vol. 234, no. 5324, pp. 75–78. Weishampel, D.B. and Heinrich, R.E., Systematics of Hyp silophodontidae and basal Iguanodontia (Dinosauria: Ornithopoda), Hist. Biol., 1992, vol. 6, no. 3, pp. 159–184. Weishampel, D.B., Barrett, P.M., Coria, R.A., et al., in The Dinosauria, 2nd ed., Weishampel, D.B., Dodson, P., and Osmólska, H., Eds., Berkeley–Los Angeles–London: Univ. California Press, 2004, pp. 517–606. Zan, S., Chen, J., Jin, L., and Li, T., A primitive ornithopod from the Early Cretaceous Quantou Formation of central Jilin, China, Vertebr. PalAsiat., 2005, vol. 43, no. 3, pp. 182–193. Zhao, X., Cheng, Z., and Makovicky, P., New ceratopsian from the Upper Jurassic Houcheng Formation of Hebei, China, Acta Geol. Sin., 2006, vol. 80, no. 4, pp. 467–473.
Translated by G. Rautian
