Mammals from the Mesozoic of Mongolia

Home , Aegialodon, Allotheria, Bissekty Formation, Cimolodonta, Cimolomyidae, Deltatheridiidae

Introduction and Simpson (1926) dcscrihed these as placental (eutherian) insectivores. 'l'he deltathcroids originally Mongolia produces one of the world's most extraordi- included with the insectivores, more recently have narily preserved assemblages of hlesozoic ma~nmals. t)een assigned to the Metatheria (Kielan-Jaworowska Unlike fossils at most Mesozoic sites, Inany of these and Nesov, 1990). For ahout 40 years these were the remains are skulls, and in some cases these are asso- only Mesozoic ~nanimalsknown from Mongolia. ciated with postcranial skeletons. Ry contrast, 'I'he next discoveries in Mongolia were made by the Mesozoic mammals at well-known sites in North Polish-Mongolian Palaeontological Expeditions America and other continents have produced less (1963-1971) initially led by Naydin Dovchin, then by complete material, usually incomplete jaws with den- Rinchen Barsbold on the Mongolian side, and Zofia titions, or isolated teeth. In addition to the rich Kielan-Jaworowska on the Polish side, Kazi~nierz samples of skulls and skeletons representing Late Koualski led the expedition in 1964. Late Cretaceous Cretaceous mam~nals,certain localities in Mongolia ma~nmalswere collected in three Gohi Desert regions: are also known for less well preserved, but important, Bayan Zag (Djadokhta Formation), Nenlegt and remains of Early Cretaceous mammals. The mammals Khulsan in the Nemegt Valley (Baruungoyot from hoth Early and Late Cretaceous intervals have Formation), and llcrmiin 'ISav, south-\vest of the increased our understanding of diversification and Neniegt Valley, in the Red beds of Hermiin 'rsav, morphologic variation in archaic mammals. which have heen regarded as a stratigraphic ecluivalent Potentially this new information has hearing on the of the Baruungoyot Formation (Gradzinslti r't crl., phylogenetic relationships among major branches of 1977). The mammal collection made by these expedi- ma~nmals. tions from all these sites contai~lsahout 1 70 specimens Simpson (192Sa) described the first Mesozoic representing ~nultituberculatesand therians (Kielan- mammal from Mongolia. This was a skull associated Jaworourska 1974, 1984~;Kielan-Jaworowska and with fragments of the postcranial skeleton of a multi- Carnbaryan, 1 Gambaryan and Kielan- tuherculate, Djnducht~~theriummntthewi, collected in Jaworowska, 199.5; Kielan-Jaworowska and Ilurum, 1923 at Bayan Zag (known also as Shabarakh Usu) in 1997, and references therein). the Gobi Desert, from rocks of the Upper Cretaceous In 6 thc Sotriet-klongolian Geological Djadokhta Formation (Figure 29.1). The specimen was Expedition found the skull of a n~ultituberculate, found by the Central Asiatic Expedition organized hy Hugi~zl/a/ztczrtm~z.rn1tninz.ri.r at Khaichin Uul in the the American Museum of Natural History in New Biigiin 'rsav region (referred to also as Rugin Cav), York (1921-1930), and led t)y Roy Chapman Andrews north-west of the Nernegt Basin (Kiclan-Jaworo\vska (see Chapter 12). Principal field participants included and Sochava, 196 Kielan--jaworowska, 107% Walter Granger who, with a snlall team, recovered 'I'rofimov, 1975). The heds at Khaichin Uul are eight additional mammal specimens in 1925. Ciregory referred to thc Upper C:retaceous and are equivalent 2. KIELAN-JAWOROWSKA etal.

Figure 29.1. Diagrammatic map of mammal-bearing Mesozoic localities in Mongolia. (1) Bayan Zag, (2) Togrogiin Shiree, (3) Ukhaa Tolgod, (4) Khulsan, (5) Nemegt, (6) Hermiin Tsav 11, (7) Hermiin Tsav 1, (8) Biigiin Tsav, (9) Khaichin Uul, (10) Guriliin Tsav, (1 1) ~iidenSair, (12) HiiGvor.

to the Nemegt Formation (Gradzinski et al., 1977). eutherian and multituberculate mammals, more rare Fossil mammals, however, were not found in the 'triconodonts' (now regarded as a polyphyletic group), Nemegt Formation in the Nemegt Basin. very rare 'eupantotheres' (a paraphyletic group), sym- From 1969 until 1996, the Soviet-Mongolian metrodonts and aegialodontids (Belyaeva et al., 1974; Palaeontological Expeditions (SMPE), led by Dashzeveg, 1975, 1979, 1994; Trofimov, 1978, 1980; Rinchen Barsbold and Demberlyin Dashzeveg on the Dashzeveg and Kielan-Jaworowska, 1984; Kielan- Mongolian side and by various Russian scientists, Jaworowska et al., 1987; Kielan-Jaworowska and principally Valerii Reshetov, worked in Mongolia. Dashzeveg, 1989, 1998; Sigogneau-Russell etal., 1992; They discovered an Early Cretaceous (Aptian or Wible et al., 1995). By contrast to Late Cretaceous Albian) mammal site at Hoovor (known also as mammals that were collected from the surface of out- Khovboor or Khoobur, and Guchin Us) in Guchinus crops and are represented by skulls, often associated Sum (county) in the Gobi Desert. This site, explored with postcranial skeletons, the fossils from Hoovor subsequently also by D. Dashzeveg (referred to further were collected using washing and screening tech- as D.D.) and the Mongolian Academy-American niques and consisted, by 1974, of about 500 isolated Museum Expeditions (see below) yielded numerous teeth and bones (Belyaeva etal., 1974). Mammals from the Mesozoic of Mongolia

Another Early Cretaceous, though less rich, samples of Early Cretaceous mammals from Hiiiiviir. mammal locality was discovered by the SMPE at The quantities of Late Cretaceous manlrnals recov- Kha~narynUs (= Gashuuny Khudag). situated south- ered exceed in numbers the collections of all previous west of the city of Sainshand in southeastern expeditions. For example, Ukhaa 'l'olgod, a new local- Mongolia. Only one mammal remain, a fragment of a ity discovered in 1903, situated at the eastern part of dentary with m2 and m3 ('Triconodonta', possibly the Ne~negtBasin, east of Khulsan, has yielded over Arnphilestidae) has been described (Reshetov and 800 mammal specimens in an unusually good state of Trofimov, 1980) froin this site. preservation (Dashzeveg et nl., 1995; Rougier ct al., 'The SMPE also collected Late Cretaceous 1996a, b, 1997, 1998; Novacek etal., 1997). mammals at various sites. Most important among During September of 1095 a small ,Mongolian- these was the discovery at ~iidenSair, in beds corre- Polish team (Yo. Khand, H. Osm6lska, 'T. Maryariska sponding to the Baruungoyot Formation, of the skull and K. Sabath) collected fossils at various localities in and postcranial skeleton of the first Late Cretaceous the Gobi Desert, including Ukhaa Tolgod where they non-deltatheroid metatherian from Asia (Trofimov recoljered remains of nine multitubcrculates and one and Szalay, 1994; Szalay and Trofimov, 1996), and the placental (Kielan-Jaworowska and Hurum, 1997; skull of a large deltatheroidan in beds possibly equiva- Kielan-Jaworowska, 1998). lent to the Nenlegt Formation, at Guriliin Tsav It should also be noted that fossil ~narnrnalshave (=Gurlin Cav), north of the Nemegt Basin been reported, but not described from Bayan (.Anonymous, 1983; Kielan-Jaworowska and Nesov, Mandahu, a locality in northern China near the 1990; Szalay and Trofimov, 1996). Mongolian-Chinese border, and thought to be equiva- Finally, at the locality of Shar 'Teeg in the Trans- lent in age to the Djadokhta Formation Uerzykiewicz Altaian Gol~i,the SMPE found the first and only etal., 1993; Wang etal., 1995) :\bout 50 skulls, three or known Jurassic mammal from Mongolia, a single tooth four with incomplete skeletons, were tentatively of a docodont that was initially identified as a symmet- identified as taeniolabidoid multituberculates, rodont (Tatariuov, 1994). although one specimen was identitied as the eutherian These samples were augmented by additional Late Ken~ialstes. Cretaceous mammals collected by D.D. at 'Tiigriigiin Gradziriski et nl. (1977) refined the descriptions of Shiree (= Tugrugeen Shireh, 'l'ugrik) in beds equiva- three Upper Cretaceous Gobi Desert formations. lent to the Djadokhta Formation, and at other sites They suggested as 'best guesses' the following ages: (Kielan-Jaworowska and Dashzeveg, 1978). A few Djadokhta Formation =?upper Santonian and/or Cretaceous mammals were found by other expedi- ?lower Campanian; Baruunpoyot Formation =?middle tions including the Italian-French-Mongolian Campanian; Nemegt Formation =?upper Carnpanian Expedition in 1991 (Taquet, 1994) and by the and ?lower Maastrichtian (see, however, Fox, 1978; Japanese-Mongolian Expeditions in 1993-1996 Lillegraven and McKenna, 1986; Jerzykiewicz et nl., (Mahito Watabe, pers. comin. to Z.KJ.). 1993, and Chapters 14 and 15 for alternative age esti- The American Museum of Natural History and the mates). These assignments were based on fresh-water lnstitute of Geology of the Mongolian Academy of invertebrates and comparisons of dinosaurs and Sciences carried out ten palaeontological expeditions mainmals with those froin European and North (1990-1999), under the guidance of Demberlyin American assemblages, essentially above the generic Dashzeveg and Michael J. Novacek. This collabora- level. Unfortunatety, without a context provided by tion, known as the Mongolian Academy-American palaeomagnetic, radiometric, or marine tie-ins, such Museum Expeditions (MAE), has produced a spectac- correlations are tenuous at best. ular coltection of Late Cretaceous mammals tiom 'I'be stratigraphic scheme of Gradzinski etnl. (1977) previously known and new localities, as well as large has been questioned by members of the Mongolian .\cadem\.-.\mcrican hluseum Project. It appears from Campanian is 3 marine stage established in Europe preliminary identifications of the fauna collected at and divided on the I~asisof' ;lmrnonites and other Lkhaa 'l'olgod, that this locality provides 3 mixture of marine invertebrates into two substages. 'I'herefore, tava known horn hot11 the lljadokhta and Baruunsoyot the tripartite division of the Ca~npanianin L\sia and formations (Novacek i2r ill., 1004; Ilashzeveg 1.l dl., North .\rnerica is inappropriate. Finally .\\.er1yanov 100.5) On this basis it has been stated: 'Sampling at (1007) stated: "The evidence from this paper, although Ukhaa 'l'olgod, as well as onsoing Ivork at other local- inconclusive a5 the tentative correlation presented ities, I)lul-s the distinction Ixt~veenIljadokhta assen- al,ove is on the generic level, supports in part the con- t)lagcs ancl allegedly slightly younger Rarui~ngoyot clusion of Gradziliski pr ill. (1077) in suggesting a assemhlagcs' (Ilashze\,eg 1.r ill., 1005, p. 447). 'l'his some\vhat earlier, perhaps early Ca~npanianage for statement contradicts the rcportecl lack of overlap the Iljadolihta Formation'. between taxa I~asedon nlorc than 200 mammal skulls, In the present account we continue to recognize collected I>\ {)re\ious expeditions from the Iljadokhta both the Iljadokhta and Baruungoyot formations. We and Karuungoyot formations ancl housed in the refer to the 1)jadokhta Formation as ?early Campanion museums in New York, Warsaw, Moscow and and the Baruungoyot Formation as ?late Calnpanian, Llaanhaatar. The only mammal species previously with the assignment of Ukhaa Tolgod pending faunal cited as occurring in both formations is I~clti~thevidi~rl~land stratigraphic analysis. pvc~tl~ilubi~vcnlnvc,stated I)y Kielan-Jauoro\vska (lC)75a) to be represented I)y difercnt subspecies (D. p. pvt.tvitu- bcvc~llnn.and D. 1). tf~v~lunz)in each formation, but den- onstratetl hy liougier ~tal.(1008) to be a single species. 1, C,P, hl are used here for the upper incisors, canines, Rougier cJr al. (1 907) relerrcd to the Uk haa 'Tolgod premolars and molars respectively and i, c, p, In, fix heds as 'Djadokhta I;or~nation ecluivalent?' and the the corresponding lower teeth. hlt I-I;, metatarsals 1n;lmmal fia~lnayielded I)? this locality contains taxa I-\: Institutions in which the collections are housed nlostly known fro~nthe Iljadokhta For111ation. In addi- are ahbrc\,iated: .\klNt4, .imcrican bluseum of tion, these heds also contain new, undescril>ed taxa, as Natural History, New l'ork; PIN, Paleontological well as \,cry rare specimens of (,'huls~zt~b~zati~vand Institute of the Russian Academy of Sciences, \cwrc:crbi~arf~v,previously knoivn only fiom the Moscow; PSS, Institute of Geology, Section of Baruungoyot Formation and Red heds of liermiin Palaeontology and Stratigraphy, .icademy of Tsav. Ilo~vever, a comprehensive anal~~sisof the Sciences, Ulaanbnatar (abbreviated also as C;1 or (;I ~ilam~nalassemt)lage from Ukhaa 'l'olgod has not heen PS'r); ZP:\L, Institute of Paleobiology, Polish published, and the stratigraphic relationships of this Academy of Sciences, Warsaw. section are the suhject of ongoing analysis. .I\,er'!.anov (1007) described se\,eral lnammal teeth Systematic review from the Late Cretaceous Ilarbasa 120rrnation of .2lymatau in southern Kazakhstan. The age of this for- Subclass i~~cc~r~z~~st.di.r ination \vas estat)lished on the basis of marine invcrte- Order Docodonta Kretzoi, 10.58 I~ratesand shark teeth as early (:anlpanian. .4ver1yano\~ (:olnttwtzt.c Docodonts are a specialized group of very argued that the presence of the rnultitul)erculate small mammals with molars that superficially resemble Ilulg~~f~bnnt~z~~in the .Ilylnatau fi~una,which occurs in those of advanced Theria (Butler, 1988, and references the lljadokhta 1;ormation and is not known from the therein; Sigogneau-Russell and Godefroit, 1007) and 13aruungoyot Formation suggests that the ,.ilylnatau are known only froni the Late Triassic, and the Middle fauna may be hetter correlated with that of the and Late Jurassic. Lillegraven and Krusat (1991) Iljadokhta Formation. He also stated that the regarded the docodonts as a sister group of all other Mammals from the Mesozoic of Mongolia

defined cuspules, situated in front of the principal cusp and forming crenulations on the anterolabial margin of the anterior basin. There is a very small posterior cingulid. The tooth is similar to Simpsonodon from the Middle Jurassic of southern England (Kermack et al., 1987), from which it differs in having three, rather than four main cusps (the anterolabial cusp of Simpsonodon being developed as two crenulations on the anterolabial margin of the anterior basin), a larger anterior basin, a less prominent posterior cinplum and a relatively higher principal cusp. Comments. Tegotherium gubini is the only representative of the Docodonta in Mongolia. Tatarinov (1994) referred Tegotherium to the Symmetrodonta. He erected for it a monotypic family Tegotheriidae and a monotypic order Tegotheriidia. Hopson (1995) Figure 29.2. Tegotheriumgubinz Tatarinov, 1994, holotype argued that Tegotherium was closely related to right lower molar, PIN 41 741167, in (A) labial, (B) lingual and Simpsonodon from Oxfordshire (Kermack et al., 1987), (C) occlusal views. Scale bar = 1 mm. (Drawn by L.P. and that together with Borealestes they form a distinct Tatarinov.) clade of docodonts. We agree and we assign Tegotherium to the docodonts. mammals, but Wible and Hopson (1993) and Wible et al. (1995) found evidence inconsistent with that con- 'Triconodonts' (= polyphyletic order Triconodonta clusion and presented a tree (Wible and Hopson, 1993) Osborn, 1888) in which the docodontid Haldanodon formed a sister Comments. Among Mesozoic mammals the 'tricon- taxon to triconodontids and other mammals to the odonts', especially the Morganucodontidae (assigned exclusion of morganucodontids and Sinoconodon. by Kermack et al., 1973, to the order Morganuco- donta), are most similar to the cynodonts. 'Tricono- Family Docodontidae (Marsh, 1887) donta' are polyphyletic, however (e.g., Rowe, 1988; Genus Tegotherium Tatarinov, 1994 Rougier etal., 1992; Wible and Hopson, 1993; Wible et Tegotherium gubini Tatarinov, 1994 al., 1995; Kielan-Jaworowska, 1997), and are thus cited See Figure 29.2. here in quotation marks. The Late Triassic-Early Holotype (and only known specimen). PIN 41 741167, right Jurassic Morganucodontidae and Megazostrodon- lower molar. Shar Teeg, Trans-Altaia Gobi, Mongolia; tidae, both of which retain a double jaw joint Late Jurassic. (Kermack etal., 1973; Jenkins etal., 1983) differ in many Description. The lower molar, which is 1.25 mm long, respects from the more modern, Late Jurassic-Early has three main cusps with an anterior basin situated Cretaceous lineages Triconodontidae and Amphil- between and in front of them. The principal cusp is estidae, which are characterized by a typical mammal- the highest and placed posterolabially; it is conical and ian jaw joint (Jenkins and Crompton, 1979; Jenkins covered lingually with longitudinal ridges. On the and Schaff, 1988). margin of the crown there are two conical cusps. They are lower than the principal cusp and the posterior is Family Amphilestidae Osborn, 1888 situated opposite the principal cusp while the other is Comments. Mills (1971) argued that the Amphilestidae located more anteriorly. There are also two, poorly would appear to belong to Pantotheria, as they exhibit a tooth morphology similar to that of k'uehneotherium ated close and slightly shifted posteriorly with respect and the 'obtuse-angled' sym~netrodonts such as to the corresponding upper molariform teeth. Fire Tinodon. Jenkins and Crompton (1970), Jenkins and molariform teeth and five to six antemolariform teeth Schaff (1988) and Kielan-Jaworowska and Dashzeveg in the dentary. The il and c are semi-procumbent, (1998) noted the similar occlusal pattern evident in pl-p3 with decreasing procnmbency, p4 (disappear- symmetrodonts and amphilestids and the latter ing in later ontogenetic stages in G. ostronzi) vertical, authors demonstrated that the interlocking mecha- with 3 cusps, molariforrn teeth with four or five cusps, nism of the lower molariforms in Gobiconodon resem- n13 the largest. Main cusps in M3-M.5 show incipient bles that of Kuehneotheriuw and Tinodo~z. Kielan- triangular pattern, with cusp .A placed slightly more Jaworowska and Dashzeveg (1998) further stated that: lingual than cusps B and C. Interlocking mechanism of "l'he data presented in this paper give some support to lower molariforms of Kueh~zeothc.riun~type, with cusp d Mills' idea on the therian affinities of the of the anterior tooth fitting into emhayment between Amphilestidae although it cannot be excluded that the small cusps e and f of the anterior cingulum of the characters that unite the two groups may have devel- succeeding molariforrn. Molariform teeth undergo oped in parallel'. replacement at least in G. o.stromi and probably G. borissiaki. 'The main cusp a of lower molariforms occluded Subfimily Ciobiconodontinae Chow and Rich, 1984 immediately in front of the distal margin of the corre- Conznzeuts. Jenkins and Schaff (1988) erected a new sponding upper molariform, between posterior cingu- family, Gobiconodontidae (neglecting Gobiconodon- lum, on which there is a small cusp D, and cusp C, tinae Chow and Rich, 1984), to include Cobicoaodo~z rather than between cusps A and B, as in Trofimov, 1978, and, tentatively, Guchinodon Trofimov, Morganucodontidae and Triconodontidae' (Kielan- 1978. Kielan-Jaworowska and Dashzeveg (1998) Jaworowska and Dashzeveg, 1998). restored the subfamily status of Ciobiconodontinae Comment.r. Kielan-Jaworowska and Dashzeveg (1998) within :\mpliilestidae. 'I'he Gobiconodontinae share argued that Guchizodo~z hoburcr~sis Trofiniov, 1978 with known amphilestids the basic structure of the diff'ers from Gobiconodon borisiaki 'l'rofimov, 1 978 in that molars, but differ from them in small details of molar it is almost twice as small, has a double-rooted p4, and structure and in enlargement of the most mesial lower by details of the position of the mental and infiaorbi- tooth. Kielan-Jaworowska and llashzeveg considered tal foramina. The dental formulae, arrangement of the these characters sufficient to warrant subfamilial, but teeth and molar structure are similar in both taxa, and not familial starus. Klamelia Chow and Rich, 1984, there are only small differences in the relative heights assigned by its authors to the Gobiconodontinae, of cusps b and c, resulting in a slightly diff'erent occlu- probably does not belong to this subfamily (Jenkins sal pattern. A specific rather than generic value was and Schalf, 1988). assigned to these differences and on this basis Kielan- Dingr~osis.See Jenkins and Schaff (1988). Jaworowska and Dashzeveg (1998) regarded Guchinodoa 'Trofimov, 1978, as a junior subjective Genus Gobiconodon Trofimov, 1978 synonym of Gobicoaodo~z'Trofimov,1978, which we also Synolzym. Guchinodon Trofimov, 1978. accept here. ljpe species. Gobiconodon borissiaki 'Srofimov 1978. Other species. G. hobure~zsi.~(Trofi~nov, 1978); G. ostromi Gobicouodon borissiaki Trofirnov, 1978 Jenkins and Schaff; 1988. See Fig. 29.3.A. Diag~zo.si.~:'Very small to medium-sized (estimated Holotype. PIN 3101/09, incomplete right dentary. skull length varies between 27 mm in G. hoburen.si.s and Hoovor, Guchinus county, Gobi Ilesert, Mongolia; 106 mm in C. o.stronzi) amphilestid 'triconodonts' with Hoovor beds (Aptian or Albian). five rounded fossae on the palatal part of maxilla, situ- Ref2.rrt.d material. Several incomplete dentaries and Mammals from the Mesozoic of Mongolia

Figure 29.3. Gobiconodon bor2ssiakiTrofimov, 1978, holotype, PIN 3101/09, incomplete right dentary in (A) labial view. Guchinodon hoburensir Trofimov, 1978, holotype, PIN 3101124, incomplete right dentary in (B) labial view. Scale bars = 5 mm (From Trofimov, 1978.)

fragments of maxillae with teeth from the type maxillae with teeth in the PIN and PSS collections, all horizon and locality in the PIN and PSS collections. A from the type horizon and locality. dentary with broken teeth (in the collections of PIN) Diagnosis. 'Differs from G. borissiaki in being about 1.8 from the Early Cretaceous Shestakovo locality in times smaller and in having a double-rooted p4; differs Siberia was recently described by Mashchenko and from G. ostromi in being almost 3 times smaller and in Lopatin (1998). having p4 which apparently does not disappear during Diagnosis. 'Medium sized Gobiconodon, estimated ontogeny. Differs from G. borissiaki and G. ostromi in length of the skull about 48-50 mm. Differs from G. having all the cusps (except cusp a) in lower molari- ostromi and G. hoburensis in dimensions, being approxi- form teeth less prominent, and cusp b in ml situated mately intermediate in size between these taxa. Differs relatively higher. The dentary is relatively wider from G. hoburensis and G. ostromi in having a single- mesially than in G. borissiaki and G. ostromi, which is rooted p4 (in G. ostromiit is incipiently double-rooted, related to a medial shift of il with respect to other either single-rooted or absorbed), which apparently teeth (it is more aligned in G. borissiaki and especially does not disappear in adult ontogenetic stages, as in G. ostromz). The three mental foramina are shifted characteristic of G. ostromi (but not of G. hoburensis). slightly more anteriorly than in the two other species, Differs from G. ostromi, apparently, in having more especially G. ostromi The palatal fossae are relatively prominent cusps e and f on the anterior cingulum of deeper than in G. borissiaki (poorly known in G. m2-m5. The difference in size between il and c is ostromz). Differs from G. borissiakiin having the infraor- smaller than in G. ostromi. Differs from G. hoburensis in bital foramen situated more anteriorly, above the having much more pronounced cusps b and c on lower P3-P4 embrasure, rather than above M1 (position not molariform teeth, and cusp b on ml placed lower. It known in G. ostromz)' (Kielan-Jaworowska and shares these latter characters with G. ostromz' (Kielan- Dashzeveg, 1998). Jaworowska and Dashzeveg, 1998). Subclass Allotheria Marsh, 1880 Gobiconodon boburensis (Trofimov, 1978) Order Multituberculata Cope, 1884 See Fig. 29.3B. Comments. The Multituberculata were a very diverse Halotype. PIN 3 101124, incomplete right dentary, group of Mesozoic and Early Tertiary mammals and Hoovor, Guchinus county, Gobi Desert, Mongolia; are often referred to as the 'rodents of the Mesozoic'. Hoovor beds (Aptian or Albian). The multituberculate skull has been described by Referred material. Several incomplete dentaries and Granger and Simpson (1929), Simpson (1937), Kielan- Z. KIELAN-JAWOROWSKA etal

Figure 29.4. Nemegtbaatargobiensir Kielan-Jaworowska, 1974. Diagrammatic reconstruction of the skull in dorsal (left)and ventral (right) views. The skull is about 40 mm long.

Jaworowska (1970, 1971, 1974), Kielan-Jaworowska braincase and there are three ear ossicles (Wliao and and Dashzeveg (1978), Clemens and Kielan- Lillegraven, 1986; Miao, 1988) that are arranged as in Jaworowska (1979), Kielan-Jaworowska and Sloan modern mammals (Meng and Wyss, 1995; Hurum etal., (1979), Sloan (1979), Kielan-Jaworowska et al. (1986), 1996; Rougier etal., 1996b).The condylar process is low Miao (1988, 1991, 1993), Hahn (1993, and references and forms at least part of the posterior margin of the therein), Gambaryan and Kielan-Jaworowska (1995), dentary, which in most forms is semicircular. There is Hurum (1994, 1998a, b), Ridulescu and Samson no angular process and the ventral margin of the (1996), Kielan-Jaworowska and Hurum (1997), dentary is inflected and forms the pterygoideus shelf Rougier et al. (1997). The skull (Figures 29.4-29.6, for insertion of the pterygoid muscles. 29.10-29.1 3) is dorsoventrally compressed, rather than The premolars and molars carry numerous cusps laterally compressed as in therian mammals, and the and, except in some Jurassic Paulchoffatiidae, they are postorbital process in most multituberculates is situ- of subequal height. In Jurassic taxa there are three ated on the parietal rather than on the frontal as in ther- pairs of upper incisors, but in later forms there are ians. The anterior part of the orbit extends anteriorly, only two pairs, and one pair of lower incisors. More at least in all well preserved skulls of djadochtatherians specialized conditions for multituberculates are rep- (see below), as a pocket-like structure (orbital pocket) resented by reduction in the number of premolars, that has no floor, but is roofed dorsally and laterally presence of a diastema and cheek teeth that are longer (Gambaryan and Kielan-Jaworowska, 1995), in con- anteroposteriorly and with a greater number of cusps. trast to almost all therians. The zygomatic arches are Multituberculates had a backward masticatory power stout, the jugal is placed on the medial wall of the zygo- stroke (Gingerich, 1977; Krause, 1982). In relation to matic arch (Hopson et al., 1989), the glenoid fossa is this, all the masticatory muscles inserted more anteri- large and flat (rather than concave as in most therians), orly than in other mammals, and the masseteric fossa slopes backwards and stands out from the braincase. and coronoid process are placed more anteriorly as The cochlea is only slightly bent, the anterior lamina of well (Gambaryan and Kielan-Jaworowska, 1995). the petrosal contributes largely to the lateral wall of the The multituberculate brain (Figure 29.6) differs Mammals from the Mesozoic of Mongolia

Figure 29.5. SloanbaatarmirabilzsKielan-Jaworowska, 1970, holotype, ZPAL MgM-1/20, skull with lower jaws in lateral view. The skull is about 23 mm long. (From Kielan-Jaworowska, 1970.) from that of primitive therian mammals in having a mammals in having a calcaneo-MtV contact and the strongly expanded vermis, in lacking midbrain expo- MtIII abducted 30' from the longitudinal axis of the sure on the dorsal side, and in the absence of the tuber calcanei (and the longitudinal axis of the body). cerebellar hemispheres (Simpson, 1937; Kielan- However, the discovery of an almost complete tricon- Jaworowska, 1986). A similar pattern is known only in odont skeleton by Ji etal. (I 999, fig. 4) demonstrates the the triconodontid Triconodon (Simpson, 1927), indicat- presence of a pes showing similar bone arrangements ing the possible relationship of multituberculates with to that of multituberculates. This position of the pes the Triconodontidae, but not with other 'triconodonts' would be ineffective in parasagittal limbs, where the (Kielan-Jaworowska, 1997). main axis of the pes extends in a parasagittal plane. The multituberculate postcranial skeleton retains Similarly, the deep multituberculate pelvis with many characters that are primitive for mammals femoral adductors originating ventral to the acetab- (Krause and Jenkins, 1983). For example, the inter- ulum and the larger mediolateral rather than ante- clavicles are present (Sereno and McKenna, 1995). roposterior diameter of the tibia also indicate The pes (Figure 29.7A, B) (Kielan-Jaworowska and abduction of the hind limbs (Figure 29.7C). On this Gambaryan, 1994) differs from that of all other basis, Kielan-Jaworowska and Garnbaryan (1994) Z. KIELAN-JAWOROWSKA etal.

BULB

PROOTIC VEIN VERMIS SIGMOID PARAFLOCCULUS SINUS

Figure 29.6. Reconstruction of the brain of the multituberculate Cbulsanbaatarvulgaris. The skull is about 20 mm long. (Modified from Kielan-Jaworowska, 1986.) reconstructed the multituberculate stance as sprawl- Late Cretaceous of Mongolia, in which humeral ing (Figure 29.8) and argued that the structure of the torsion is 31" (Kielan-Jaworowska, 1998). Gambaryan lumbar vertebrae, with long transverse and high and Kielan-Jaworowska (1997) recognized several fea- spinous processes shows that multituberculates were tures characteristic of the humeri that indicate a pri- adapted for asymmetrical gaits with steep jumps. marily sprawling stance. The most important of these Sereno and McKenna (1995) demonstrated that in is the presence of prominent radial and ulnar con- the Late Cretaceous Mongolian taxon cf. Bulganbaatar dyles, and absence of a trochlea, traits found in parasa- the humerus shows only a small degree of torsion gittal forms. Torsion of the humerus occurs in (15') and on this basis concluded that multitubercu- terrestrial tetrapods with abducted forelimbs, that use late forelimbs operated in a parasagittal fashion. symmetrical diagonal gaits, but not in anurans, which However, the humerus of cf. Bulganbaatar differs con- have abducted forelimbs, but use asymmetrical jumps, siderably from that of ?Lambdopsalis, a Palaeocene and, with the exception of Chrysochloridae, not in multituberculate from China in which the torsion fossorial therians with a sprawling or semi-sprawling approaches 38" and from that of Kryptobataar, from the stance. Therefore Gambaryan and Kielan-Jaworowska Mammals from the Mesozoic of Mongolia

Figure 29.7. Kyptobaatavdashzaregi Kielan-Jaworowska, 1970, ZPAL MgM-1/41, Reconstruction of the right pes in (A) dorsal and (B) plantar views (based on the specimen in C). Pelvic girdle and hind limbs in (C) left lateral view. The arrow points to the epipubic bone. X 2.5. (Modified from Kielan-Jaworowska and Gambaryan, 1994.)

(1997) argued that the lack of torsion is not always Jurassic), the idea that parasagittalism occurred in indicative of parasagittalism. They further argued mammalian evolution in common ancestors of ther- that, as there is no trace of even an incipient trochlea ians and multituberculates does not hold. in any known multituberculate (the trochlea made its In the multituberculate pelvic girdle, epipubic appearance in therians possibly during the Late ('marsupial') bones are present (Kielan-Jaworowska, Z. KIELAN-JAWOROWSKA etal.

Figure 29.8. Reconstruction of the posture of the multituberculate Nemegtbaatar. (Modified from Kielan-Jaworowska and Gambaryan, 1994.)

1969b; see also Figure 29.7C). The pelvis is deep and Jaworowska (1979) concluded that multituberculates very narrow, with a small ischial arc and a process-like may have been viviparous. ischial tubercle, and there is a long ischiopubic sym- The origin and relationships of multituberculates physis with a ventral ridge. The length of this ridge to other mammals is controversial. In recent analyses, and the degree of fusion indicate that the pelvis was multituberculates have been regarded as: (1) a sister rigid and could not have spread apart during parturi- taxon of the Theria (e.g., Rowe, 1988, 1993; Lucas and tion. The profile of the passage within the ischial arc is Luo, 1993; Sereno and McKenna, 1995; Ji etal., 1999); triangular and the space available for the passage of an (2) a sister taxon of Monotremata + Theria (e.g., egg is so small, that any known cleidoic egg could not Miao, 1991; Wible, 1991; Lillegraven and Hahn, 1993); have passed through it. On this basis, Kielan- (3) a sister taxon of the Monotremata, both groups .\larnrnals from the .\lesozoic of llongolia

together being a sister taxon of the 'Sheria (e.g., dentar!. of a I'alacocene suda~nericid Slidi~lt~t~icn, Kielan-Jaworoivska, 1971; Kemp, 1083 - tentativel!.; ii-ith t\vo rnolariform teeth and tn.o Inore inolar loci Wible and Hopson, 1993; hleng and Wss, 1095); (4) rl posterior to thern. .SIL~/LII~IC~-I~~Iapparently had four sister taxon of all other rnamruals (e.g., llcKenna, rnolariform teeth, a condition unkiionn for nlultitu- 1087; kliao, 1993; Kielan-Ja~i-oron-ska and bcrculates, lie agree with I'ascual pt ill. (1999) that (iarnbaryan, 1994). Gond~vanatheriamay not belong to hlultirubercolata, Information on Idate Cretaceous .\longolian niulti- but we believe that some fossils fro~u the Late tuberculates has an important bearing on argximents Cretaceous Los .\lamitos Formation of Argentina, regarding the relationships of multituherculates to tcntati\.el\. attrih~ltedto Ferugliotheriidae, might bc other mammals and niamrurllian ph!.logenetics multituberculates. 'These are: upper pre~nolars,with (Novacek, 1990). Data on the structure of the multitu- fen. conical cusps, similar to thosc of ~nultituhercu- berculate skull, the hrain (as inferred frorn endocra- lates (described h\ Krausc rt nl., I()')?), and a dentar!, nial casts), the ear region and the postcranial skeleton nith an a11 eol~lsfor an incisor, a diasteina, and a blade- are based primarily on the rich collections of I-ate like preniolar ~vithridges (+A), sinlilar to those in Cretaceous rilultituberculates from .\longolia, onl!- a ~ilultituberculates(descril~ed b!. Kielan-Jalvoronska part of which have been described so far (Kielan- and Bonaparte, 100;). Jaworowska, 1070, 1971, 1974, 1086, 1994, 1998; In this revie~vwe regard llultituberculata Cope,

Kielan-Jamoro~vska tzt rrl., 1986; ITible and Hopson, 1884 as an order n ithin the subclass .-\llotheria hlarsh, 1993; Hururn, 1994, 1998a, b; Kielan-Jan.oro~vsl;a and 1880, and ne adopt the fo1lon.ing s!rsternatic arrange- Garnbaryan, 1994; Novacek c,t nl., 1994; Dashze\.eg rt ment. nl., 1905; Sereno and hIcKenna, 1095; Cambaryan and Kielan-Jaworo~vska, 1995, 1997; Kougier pt ill., 1996h, 1. Suborder 'Plagiaulacoidea' Siinpson, 192.5a, 1997; Kielan-Jan-oron.ska and Hururn, 1997). Hahn, 1969. This contains seven families: Material of purported rnultituberculates from the l'a~lcho~atiidae,Pinheirodontidae, .\llodontidae, Early and hliddle Jurassic consists of a fen. fragmerl- l'lagiaulacidae, Eobaataridae, Lohahaataridae, tary teeth known only frorn Europe (Freenian, 107'): .\Il)ionbaataridae, and the genus Glimdo~l,assigned Hahn et nl., 1087; Kerrnack, 1988, aiid references to 'l'lagiaulacoidea' i~lcrrtn~sr,di.c 'Plagiaulacoidea' therein). These teeth ma!, be those of rnultituhercu- are kn0n.n from the :.\liddle Jurassic to Earl!, lates, but this cannot he unequi\ ocall!- demonstrated. Cretaceous of the Sorthern I lemisphere. However, I'.bl. Butler ( pers. coniln., 1909) infc~rrnedus 2. Suborder i~~ci,i.ti~i~s~ilis, f:i~nil!. -1rginbaataridae. that in the collection of isolated teeth frorn -1ginbaataridae are knon-n only from the Early Kirtlington, Oxfordshire, housed in the Satural Cretaceous of .\longolia. History bluseum, London, there are icolated lower 3. Suborder Cimolodonta .\lcKenna, 1975, nith three and upper fourth premolars that helong to rnultituber- infraorders: Djadochtatheria, 'Taeniolahidoidea culates. l'he nest unequi\.ocal multituherculates are (limited to a sole famil!. Taeniolabidae), and frorn the Kimrneridgian of Portugal (blahn, 1060, Ptilodontoidea; four families left in an infraorder 1993, and references therein). il~c~i-tnr~.rizdi.c Cimolorn!idae, Eucosmodontidac, The South American <;ondnanatheria haw been Jlicrocosmodontidae, and Kogaionidae; and tentatilrely assigned to 'Plagiaulacoidea' (e.g., h!- se\.eral incompletely knon-n genera, lefi in an infra- Krause et ill, IOOZ), but according to Pascual i.t dl. order and farnil! i~lcc,l-tilcsi~i1i.c. Cimolodonta are (1900) should be classihed as lIa~mrnrlliailli.t,rtnc..ctdii~. kno~vnfrom the Earl! Cretaceou~to Eocene of the <;ondn.anatheria include two families, the hrach!.o- Sorthern Hemisphere. dont Fcrusliotheriidae and thc acl\.anced h!.spodont 4. :llultituberculat:~ i~lcc~i,ti~r>s~,dic - here n.e assign, Sudamericidac. Pascual ct ill. (1000) described rl tentati\.el!., the multitu1)erculate-like upper premolars and a dentary with a premolar (?pt), that assigned to subfamil!. iilcr~-tire.redi.s may also belong 11al.e been tentatively referred to the gond- here. nanatherian penus Frrtdgliotbc.rirdtti. These fossils are Ceograpbirirl nizd.rti-atigifrpbicnl riri~g.Early Cretaceous known only from the Late Cretaceous of .\rgentina. of Europe and .1sia. For f~~rtherdata the reader is referred to Simpson Diirgi~o~i~(emended after Kielan-Jal\.orowska and (1028, 1020),Sloan and \-an I7alen (106;), Hahn (1969, Ensorn, 1992). Eobaataridae difer from most 1903, and references therein), Clemens and Kielan- Plagiaulacidae in having a limited enamel band on the lalvoron.ska (19) ;\rchibald (108) Kielan- lower incisor and share this character u-ith Clirodoiz Engelinann and Callison, 1009 and many cimolodon- Jaworo~vskatjt 01. (1087), Bakker (1002), Krause rt 01. (1002), Kielan-Jaworo~vska and Ensom (1992), Eaton tans. The ml and in2 are as!.mmetrical and shorter lin- (IOOj), Kielan;Tan.oro~vska and Bonaparte (1006), guall!. than labially, -['he P5 lacks labial cuspules and Sigogneau-Russell (IOOI) hIcKenna (1975), h11 has a posterolingual wing that is inore prominent Rddulescu and Sanlson (1006), Roueier rt 01. (1907), than in the Plagiaulacidae. Eobaataridae differ frorn en gel man^^ and Callison (lOOO), llahn and Hahn Paulchofiatiidae, Plagiaulacidae, and Ptilodontoidea (lOOO), and Fox (1000). in havinpgigantopris~naticenamel, and share this character 11-ith Arginbaataridae and most Cimolodonta.

Suborder 'Plagiaulacoidea' Siinpson, 1025a, tiahn, Co11111lt'itt~:Eobaataridae are morphologicall! 7 lnterme-' I 060 diate between some Late Jurassic Plagiaulacidae and Cori/inrirt. Simmons (199.;) and Rougier pt 01. (1907) the Cretaceous-Tertiary Cin~olodonta.Eobaataridae argued that 'Plagiaulacoidea' are paraphyletic; \ve have three Ion-er premolars, which are relatively follo\v this opinioi~and therefore cite this name in smaller than those in the Jurassic Plagiaulacidae quotation marks. 'She subordinal name Plagiaula- (~vhichha\-e three to four lo\vcr premolars), and the p4 coidea (Simpson, 1025a) has been commonly used for is relatively large, parallel-sided and does not over- man!. years. Hon.e\-er, the Iittt,i-icntioitnl Coiizii~iuioitoil hang the p3 (it docs so primitively in Eucosrnodon- Zoologicit1 kiirt~ttrlitt~~n~( 1000) recommends using the tidae, Djadochtatheria, and Ptilodontoidea). There is suffix 'oidea' for superfarnilies. 'I'herefore this name no row of accessory basal cusps on pt (a characteristic of the Plagiaulacidae), but the posterior basal cusp is should he replaced by another one, adequate for the .. suhorder. \lcKenna and Bell (1997) chose not to use present. lhere are five upper premolars (as in the 'Plagiaulacoidea' because this taxon is paraphyletic, Plagiaulacidae). using instead the Family name Plagiaulacidae Gill, 1972, in \vliicli they included paulchofiatiid, allodon- Genus Eobiratar Kielan-Jaworonska etirl., 1087 rid, and sorne plagiaulacid genera. IY? do not support Typt,.rpt~rit~~:Eobnirtirr irlngitu.r Kielan-Ja\vorowska, this procedure, helie\-ing that some 'plagiaulacoid' Dashzevey and Trofimov, 1087. Families are monoph!.letic. 'Plagiaulacoidea' arc a prade group characterized Eobantnl- ii1irgitu.r Kielan-Jaworolvska et al., 1987 by four blade-like lo\ver premolars (rhree in advanced See Figure 29.9.1. forms) that are rectangular ill lateral \,ie\v. These char- Holot~pe. PIN 3 101 157, left p4. Hiiiiviir, Guchinus acters are apomorphic for hlultituberculata, hut ples- county, Gobi Desert, XIongolia. Hiiiiviir beds (Aptian iornorphic within the group. or ;\lbian). R~fil-ngd)ilntrnal. ;\bout 20 isolated lower and upper Family Eobaataridae Kielan-Jan-oro\vska rtirl., 1987 teeth in the PIN and PSS collections. See Kielan- Iitcludt~i gt~ict7)rir.I.oxir-irrd1ir.1- Sirnpson, 192 8; Eobnntar Ja\vorox\-ska rt 01. (1987, p. 6) for a description of the Kielan-Ja\voro\vska t3t irl., 1987; the poorly kno\vn method of matching isolated teeth. .\foitobi~itti(rKiclan-Jaxvoro\\-sk:~ (,t nl., 1987, currently Drscril~tioic. Estimated skull length is about 30 mm. Mammals from the Mesozoic of Mongolia

Figure 29.9. Comparison of p4 and adjacent teeth of Early Cretaceous multituberculates from Hoovor, Mongolia. (A), Eobaatar magnus, holotype, PIN 3101/57, left p4. (B), Eobaatarminor, holotype, PIN 3101/70, fragment of the right lower jaw (reversed), with anterior part of p4, p2 and alveolus for incisor, p3 reconstructed. (C), Arginbaatardtmtm'mae, holotype, PIN3101/51, right p2-p4 (reversed), preserved in lower jaw. (D), Arginbaatardimitrimae, PSS 10-12, left p4 showing older ontogenetic stage than the specimen in Fig. C; p4 is rotated over reduced p3, while p2 has disappeared. (Modified from Kielan-Jaworowska etal., 1987.)

The p4 is rectangular in labial view, 3.1-3.6 mm long, orly than the p4 in E. magnus. The ridges on p4 are with 9-10 serrations and bearing ridges and a V- weaker and more closely arranged than in E. magnus. shaped groove above the basal cusp. There are 4:2 cusps on ml and 3:Z on m2. The second labial cusp on Eobaatar sp. ml is larger than the others. M1 has 3-4 cusps and a Description. In addition to the specimens assigned to E. small crescentic posterolingual wing. M2 has 1:3:3 magnus and E. minor, Kielan-Jaworowska et al. (1987) ~L~L~LICLCJCLLLLLC yuaLL~uuugua~WIIL~. IVIL I.,., IICU~;,~~*Jauu L. IIILI~VI, ~uL~au-jawu~uwanaC' UY. (1 7" I 1 cusps and a straight anterior margin. The lower molars described two incomplete lower incisors as Eobaatarsp. are ornamented with comma-shaped grooves, while a and Eobaatar sp. b. These incisors differ from those of the upper premolars and M1 are ornamented with most 'Plagiaulacoidea', except for the North prominent striae. In m2 only, the anterolabial wing American Glirodon (see Engelmann and Callison, and a middle medial cusp are ornamented with 1990) from the Morrison Formation, in having a grooves and striae. limited enamel band, but share this character with numerous Cimolodonta. Eobaatar minor Kielan-Jaworowska, Dashzeveg and Trofimov, 1987 Subfamily incertae sedis See Figure 29.9B. Genus Monobaatar Kielan-Jaworowska et aX, 1987 Holotype. PIN 3 101/70, incomplete right dentary with Type species by monotypy. Monobaatar mimicus Kielan- alveolus for incisor, pZ, the roots and crown fragments Jaworowska etal., 1987. of p3 and anterior part of p4. Hoovor, Guchinus somon, Gobi Desert, Mongolia; Hoovor beds (Aptian Monobaatar mimicus Kielan-Jaworowska et al., 1987 or Albian). Holotype. PIN 3101/6S, incomplete left maxilla with Referred material. An incomplete p4, PSS 10-23, from PZ-P4, broken alveolus for P1 and anterior alveolus the type horizon and locality, is also tentatively for PS. Hoovor, Guchinus county, Gobi Desert, assigned to this species. Mongolia; Hoovor beds (Aptian or Albian). Description. E. minor is smaller than E. magnus and the Refered material. The following specimens in the PSS estimated length of the skull is about 10 mm. There is collection and all from the type horizon and locality a short diastema between the incisor and p2. The p4 is are assigned to this species: a fragmentary left maxilla distinctly lower and apparently shorter anteroposteri- with P1 and PZ, a left P4, and possibly a left M2. Desc~ptiuii.The estimated length of the skull is ahout lo~verand five upper premolars, and possibly an upper 20 mm. 'There is a single infraorbital foramen posi- canine. .]'he p2 is peg-like. 7'11e p.3 is douhle-rooted tioned aboie the P3-P-l embrasure. The posterior and its length equal to 1 '7 that of p-l. l'he most char- margin of the base of the z\-gomatic arch is situated acteristic feature is a fan-shaped p-l, \\ithour a basal above the P-l-Pi embrasure. There are 3:4 cusps on cusp arid I\ ith l s-18 serrations. The enamel on p-l is P-l, the second cusp of the labial ro\v being the largest. limited and co\.ers onl!. the anterior and posterodorsal $12 has a \veakl!- signioid anterior margin and 1:2:3 parts of the cro\vn. In early ontogenetic stages the relativel! robust cusps. posterior part of p-l is ohscured h!, hone. The p-l rot:ited antero\entrally during ontogeny, over the Suhorder rrrrr~rtntJ.rt,t/i,~- Ivorn p2 and p3, nhich disappeared in later ontoge- Fa~nil~.;\rginbaataridaeHahn and Hahn, 1083 netic stages. The anterior root of p-l is snlaller than the Cui~rtt/r,irt.This is a monot!pic, highl!. specialized posterior and both roots are open. The m1 is small, 2.7 farnil!. and includes onl!. a monotypic genus tiines sliorter than p-l, 11-ith 3:2 cusps and a sigmoid .4i;

-+:-+:ridge;kI2, 1:-7:3;p4,8 serrations and basal cu\p: ni I. rather thiln 5:i:2, and from QJ'ndochtathevium and 43; 1112, 2:1. (.'~to/).ihii~tiii-inha\ ing a shorter snout (but longer than in non-dj~ldocl~tatheriiddjadochtatherians), a rela- Famil!, 1)jadochtatheriidac Kielan-Ja\\ orov ~kaand ti\cl\- less robust lo\ver incisor, and less prominent Hururn, 190; massetcric and parietal crests. 'ljpcgc~irus. I~J'~doc/itntht~i~i~~itiS impson, 192 5a. 7jpc' spl~ic,~:Krlptohniztilr dn.rhzc'i't;qi Kielan-Jaworo- Iirciuded gcirevn. QJ'ndoc/~tirt/~et-i~/ttiSi rnpson, I 02 7 a; \vhka, 1070. h.t:)ptohiriltirv Kielan-Ja\\oro\vska, 10;O; Cirto/)sbnirtiri- Ot/icai- .iplzc.ri3.r. hr)ptobirirtir/- .I-i~ichnircirsis(Kiel andaworo-

Kielan;Ta\voro\i ska, 1004; Tottibnntizi- Rougier 1.1 ([I., wska and Dashze\ eg, 1078). I 007. Uiagirosis (nioditied frorn Kielan-Ja\\oro\isla ant1 h~i:)ptoh~rirtirii/ir.n()z~~~c~rKielan-Jaworowska, 1070 Hururn, 1997). Iljadochtatheriidae difer from all See Fipnres 29.7 and 29.10. other rnultituberculates (and all other niarn~n~ilh\in 1loiot)p~:ZI-'.IL 1Ig11-I '21, rostru~nassociated with ha\ ing a subtrapezoidal snout in dorsal \,ie\i, \\-it11 a ri~htand left incomplete dentaries. Bayan Zag, Gobi \vide anterior margin and lateral rnar~insconllucnt Deqert, \Longolia; Dj~ldokhta Formation (?early \\it11 the z\.gon~aticarches rather rhan incurled in (:alnp~lnian). front of the arches. They ditkr frorn other 1nen1bel.sof' Kc;/i>ri?'i/itintc~ii~i. *liventy one specin~ens(incomplete the Iljadochtatheria in ha\-inp a snout that extends for ~kulls often associated \i-it11 dentaries) from the YO% or more of the skull length (rather rhan for lesh Djildokht;1 Formation at Ra\,an Zag in the ZPL4Lcol- than 49(X))..l'he\. share n-ith Chrrisnirbilntni- rivo pairs of lection, ;lnd five specimens from Tiigriig and more vascular foramina on the nasals and \i-ith than 150 cpecimens frorn Ukhaa Tolgod in the PSS Chrlisaltbnntni; hhiirptobirirtiri; and Taeniolabidae thc collections. lack of palatal acuities. l)~:~~i.i~rp/roir.The length of the skull reaches 32 innl. The facial surface of the lacrimal is relatively smaller Genus Kqptobirntirr Kielan-Ja\\ oron-ska, 1070 than in C'ntopsbira/irr and the postorbital process ~nuch S~iroi~yt~.~.Cobihnn/ni- Kiclan-Ja\voro\i ska, 10;0, and shorter th an in I~jirdochtnthct,ir~i~rand Catopshantnv. 'l'he Yugl-ighntnr Kielan-Ja\\.oro\vska and Dashzei eg, 1078. cusp formula for P4 is 24; All, -t5:4:3--5; M2, 1:2:3. Dii~girosir The smallest member of the Djadochta- The p4 has ce\ en ridges and a basal cusp; ml, cusps 4:3; theriidae (skull length 15-32 mm). This genus is most and m2, 3:2. '17he angle betaeen the lower rnargin of similar to QJ'ndoch/otht~r-irriir,with \\hich it shares an the dentar\- arid the occlusal surface of the molars is arcuate p4 (rather than trapezoidal as in Cntqtsbi~izti~i-). ahout 1lo. .in unusuall\. a-ell preserved pelvic girdle 'l'he p4 in hvyp/obnatirv is relati\ el\. longer rhan in and hind limbs are also known for Kg,ptobnntnr(Figure QJ'adoc/~tnthczi-iuttrand has eight serrations (unknown in 20.7c;). DJ'ndochtuth(~viuttr).h tptobnntnr di fers from DJ'ndoc/)tiz- ~ht't,irlitrand Cntopsbirirti~t-in ha\ ing a relativel!~smaller h i~ptob~rirtiri-l.iricbi~~~~~t~.ri.r(Kiel an-Jaworows ka and facial surFace of the lacrimal and a shorter postorl)ital Dashzeveg, 1978) process. It diKers tiom Catop.rbantot, and Tot116n~ti11.in Iloio!)p- lirtrii oiril kiro;~'ir SP~T~NIPI~).PSS 8-2 PST, a ha\ ing four upper premolars, and from Ctrtopsbi~ntiri-in damaged skull associated \vith both dentaries and an that the inner ridge of the 111 extends for less rhan a inco~nplete postcranial skeleton. Tiigriig, Gobi half, or a half of the tooth length. It shares a short Desert, 1lonpolia; l'iigriig beds, equivalent to the inner ridge of the 111 n ith C'huirnirbiratirt; Sloa~rbi~i~ti~i;1)jadokhra Formation (?early Campanian). 7bitrbailtilr, and Pnt,ircitirevoitIys from North .Imerica D(~.rci-iptio~rnlrd coiirtirarts. K. snzc/7anensi.r diffkrs from K. (Lillegraven, 1960; ;\rchibald, 1982). It diEers froin di~.rbzt,i.t.yiinha\-inp a slightly longer b11, and 4:2 cusps filirhirn/av in h;l\ring 111 cusp formula of -t5:4:3-5 in n11 (32 ink: dirsbzc:~cgi). In addition, the palatal part Mammals from the Mesozoic of Mongolia

Figure 29.10. KryptobaatardazhzevegiKielan-Jaworowska,1970, PSS MAE 101, skull associated with both lower jaws and incomplete postcranial skeleton, Ukhaa Tolgod, Gobi Desert. X 3.

of the premaxillary-maxillary suture occurs in front Djadocbtatberium mattbewi Simpson, 1925a of PI rather than on the level of PI, and there seems to Holotype. AMNH 20440, rostra1 part of the skull asso- be a smaller glenoid fossa, placed more laterally, on a ciated with both dentaries and fragments of the post- longer stem. There is also a small foramen of unknown cranial skeleton. The upper and lower molars are not function in the middle of the palatal part of the pre- preserved and right p4 is badly damaged. Bayan Zag, maxilla, though a similar foramen occurs on one side Gobi Desert, Mongolia; Djadokhta Formation (?early of the premaxilla in a skull of ?K dasbzevegi from Campanian). Ukhaa Tolgod, and thus this cannot be a diagnostic Refwred material. An incomplete right dentary from character for K saicbanensis. In the dentary, distinc- Ukhaa Tolgod, GI 51301, and a skull (not described) tions consist of the presence of a smaller mandibular found by the Japanese-Mongolian Expedition at condyle, facing more dorsally, with a longer and more Togrog in 1994. laterally directed ascending ramus. Description. Skull length is about 50 mm and the ml cusp formula is 4:3. D. mattbewi differs from Djadocbtatberium Simpson, 1925a Kryptobaatar in being distinctly larger, but shares with Type species by monogpy. Djadocbtatberium mattbewi Kryptobaatar and Catopsbaatar a similar shape of the Simpson, l925a. snout. It shares with K~ptobaataranarcuate p4 and the Z. KIELAN-JAWOROWSKA etal

Referred material. Two skulls from Hermiin Tsav, one of which is associated with incomplete dentaries, and a left m2 with a fragment of a dentary from Khulsan, all in the ZPAL collection. Description. The length of the skull is about 60 mm. C. catopsaloides is similar to Djadocbtatberium in the shape of the skull, but differs from it and from other djadochtatherians in having a very long snout and an orbit situated far posteriorly. The glenoid fossa is wide and roughly oval in shape. C. catopsaloides differs from Djadocbtatboium in having only three upper premolars (the P2 is absent), and a less arcuate and distinctly smaller p4. The cusp formula is: P4, 5:l; MI, 5:5:4; M2, 2:3:3; p3 present, p4 small, with 3 cusps and basal cusp, no ridges; ml, 4:4; m2, 2:2. By contrast to most djadochtatherians and eucosmodontids, the condylar process is situated above the level of the molars and the coronoid process is relatively large.

Genus Tombaatar Rougier et al., 1997 Type species by monotypy. Tombaatar sabuli Rougier et al., 1997. Figure 29.1 1. Catopsbaatarcatopsaloides (Kielan-Jaworowska, 1974), holotype, ZPAL MgM-1/78, skull in ventral view. Red Tombaatarsabuli Rougier etal., 1997 Beds of Hermiin Tsav, Hermiin Tsav 11. X 1.4. (Modified from Kielan-Jaworowska, 1974.) Holotype (and only known specimen). PSS-MAE 122A, a fragmentary rostrum and anterior portion of the braincase, with most of the dentition. Ukhaa Tolgod, Nemegt Basin, Gobi Desert, Mongolia; Ukhaa Tolgod presence of four upper premolars, though in this beds (?early Campanian). respect it differs from Catopsbaatar and Tombaatar, Referred material. Additional specimens, possibly refer- which have three upper premolars. It shares with able to Tombaatar, have recently been recorded at Catopsbaatar a very long postorbital process and a Ukhaa Tolgod by the MAE. robust lower incisor. Description. This is a large djadochtatheriid, generally similar to Djadocbtatberium and Catopsbaatar. It shares Genus Catopsbaatar Kielan-Jaworowska, 1994 with Catopsbaatarthe absence of P2 and differs from all Type species by monotypy. Catopsbaatar catopsaloides djadochtatherians in having a cusp formula of MI (Kielan-Jaworowska, 1974). 4:5:2. The 13 alveolus is formed by both the premaxilla and maxilla, and there is a very prominent postpala- Catopsbaatar catopsaloides (Kielan-Jaworowska, 1974) tine torus. The lower jaw is not known. See Figure 29.11. Holotype. ZPAL MgM-1/78, an almost complete skull Family incertaesedis associated with both dentaries. Hermiin Tsav 11, Gobi Genus BulganbaatarKielan-Jaworowska, 1974 Desert, Mongolia; Red beds of Hermiin Tsav (?late Type species. Bulganbaatar nemegtbaataroides Kielan- Campanian). Jaworowska, 1974. Mammals from the Mesozoic of Mongolia

Figure 29.12. Bulganbaatarnemegtbaataroides,PSS MAE 103, skull associated with incomplete postcranial skeleton. Djadokhta Formation, Bayan Zag. Stereo-pair. X 1.5. (From Sereno and McKenna, 1995.)

Otberspecies. ?Bulganbaatar sp. This taxon is based on a Genus Nemegtbaatar Kielan-Jaworowska, 1974 P4 from the early Campanian of southern Kazakhstan Type species by monotypy. Nemegtbaatar gobiensis Kielan- (Aver'yanov, 1997). Jaworowska, 1974.

Bulganbaatar nemegtbaataroides Kielan-Jaworowska, Nemegtbaatargobiensis Kielan-Jaworowska, 1974 1974 See Figures 29.4 and 29.8. See Figure 29.12. Holotype. ZPAL MgM-1/81, an almost complete dor- Holotype. ZPAL MgM-1/25, damaged rostrum with soventrally compressed skull, associated with both teeth. Bayan Zag, Gobi Desert, Mongolia; Djadokhta dentaries and most of the postcranial skeleton. Formation (?early Campanian). Hermiin Tsav 11, Gobi Desert, Mongolia; Red beds of Referred material. In addition to the holotype, there is a Hermiin Tsav (?late Campanian). complete skull with lower jaws, shoulder girdle and Referred material. This species is known from several almost complete forelimbs, PSS-MAE-103, also from well preserved specimens in the ZPAL and PIN col- Bayan Zag (Sereno and McKenna, 1995). lections, from Hermiin Tsav 11, Khulsan and Nemegt Description. B. nemegtbaataroides is similar to localities. Nemegtbaatar in having lateral margins of the snout Description. The skull is 40 mm long thus N.gobiensis is that are strongly incurved in front of the zygomatic larger than Kryptobaatar, but smaller than other dja- arches (they are not incurved in Djadochtatheriidae) dochtatheriid taxa. This species differs from other and one pair of palatal vacuities. The cusp formula is: members of the Djadochtatheriidae in having a P4, 2:s; MI, 5:5:3; M2, 1:2:2. There are more cusps on differently shaped snout, in which the lateral margins MI than in Kryptobaatar, Cbulsanbaatar and Sloanbaatar, are incurved in front of the zygomatic arches, a feature and the M1 has a long lingual ridge, in which it resem- it shares with other djadochtatherians. The anterior bles Nemegtbaatar. B. nemegtbaataroides differs from part of the snout is narrow and elongated. Further Nemegtbaatar in being smaller and in having a smaller differences include the presence of one pair of palatal number of cusps on the P4 and upper molars. vacuities and five pairs of vascular foramina on the Z. KIELAN-JAWOROWSKA etal. nasals. Nemegtbaatar differs from all other djadochtatherians in respect of the cusp formula which is: P4, 3:6:1; M1, 6:7:4; M2, 1:3:2 (Figure 29.4); p4 with 7 ridges and basal cusp; ml, 5:4; m2, 3:2. The taxon closest to Nemegtbaataris Bulganbaatar, which, however, is smaller and has fewer cusps on P4 and on the upper molars. Well preserved postcranial skeletons of Nemegtbaatar and Kryptobaatar enabled Kielan- Jaworowska and Gambaryan (1994) to reconstruct multituberculate postcranial musculature and dem- onstrate an abducted limb posture (Figure 29.8).

Genus Cbulsanbaatar Kielan-Jaworowska, 1974 Type species by monotypy. Cbulsanbaatar vulgaris Kielan- Jaworowska, 1974.

Cbulsanbaatar vulgaris Kielan-Jaworowska, 1974 See Figure 29.6. Holotype. ZPAL MgM-11139, a partly damaged skull associated with left and incomplete right dentaries. Khulsan, Gobi Desert, Mongolia; Baruungoyot Formation (?late Campanian). Refered material. This is the commonest species in the Baruungoyot Formation and in the Red beds of Figure 29.1 3. Kamptobaatar kuczynskii Kielan-Jaworowska Hermiin Tsav, at Khulsan, Nemegt and Hermiin 1970, holotype, ZPAL MgM-1/33, skull in ventral view. Tsav 11, and is represented in the ZPAL collection by Djadokhta Formation, Bayan Zag. X 5. (From Kielan- some 36 specimens consisting of skulls often asso- Jaworowska, 1971.) ciated with dentaries and fragments of the postcranial skeleton. Description. Cbulsanbaataris the smallest representative Kamptobaatarkuczynskii Kielan-Jaworowska, 1970 of the Djadochtatheria and the skull length varies See Figure 29.1 3. around 18-22 mm. Like other members of the Holotype. ZPAL MgM-1/33, skull with broken zygo- Djadochtatheriidae it lacks the palatal vacuities and has matic arches of a juvenile individual. Bayan Zag, Gobi two pairs of vascular foramina on the nasals, but differs Desert, Mongolia; Djadokhta Formation (?early from this family in being distinctly smaller and in Campanian). having anterior margins of the skull that incurve in Referedmaterial. Three incomplete skulls in the ZPAL front of the zygomatic arches, and a rectangular snout. collection, two of which are associated with dentaries. It also differs from other djadochtatherians in respect of Description. The snout in Kamptobaatar is incurved in the cusp formula, which is: P4, 2:6; MI, 4:S:ridge; M2, front of the zygomatic arches, with the anterior part of 1:2:2; p4 has 7 ridges and basal cusp; ml, 4:3; m2,2:2. the arches directed roughly transversely, or postero- laterally. The anterior part of the snout is relatively Genus KamptobaatarKielan-Jaworowska,1970 wide, rectangular and blunt. The glenoid fossa is Type species by monotypy. Kamptobaatar kuczynskii approximately half-oval, and oriented anterolaterally. Kielan-Jaworowska, 1970. There are asymmetrical vascular foramina on the Mammals from the Mesozoic of Mongolia nasals, no palatal vacuities, and the foramen ovale is divided into five foramina (two in other multituberculates). The dentary is relatively short and the coronoid process is low and triangular, flaring laterally as in Sloanbaatar and Nesovbaatar. The mandibular condyle, which is situated at the top of the rounded posterior edge of the dentary, faces dorsally, not posterodorsally as in most djadochtatherians. The cusp formula is: P4, A 3:s-6; M1, 5:S:ridge; M2, 1:2:3; p4 with 7 serrations with ridges; ml, 4:3; m2 unknown.

Genus Nesovbaatar Kielan-Jaworowska and Hurum, 1997 Type species by monotypy. Nesovbaatar multicostatus Kielan-Jaworowska and Hurum, 1997.

Nesovbaatar multicostatus Kielan-Jaworowska and Hurum, 1997 I 2 rnrn I Holotype. ZPAL MgM-11103, both dentaries with dentition (incisors broken). Hermiin Tsav 11, Gobi Figure 29.14. Buginbaatar transaltaiensis Kielan-Jaworowska Desert, Mongolia; Red beds of Hermiin Tsav (?late and Sochava, 1969, PIN 3487. (A), Right Ml and M2 and left Campanian). P4, incomplete M1 and M2 in occlusal view. (B), Left lower Description. The specimen is a juvenile, the length of jaw in labial view. (Modified from Trofimov, 1975.) the dentary, measured from the base of incisor to the posterior end of the condyle, is 13.5 mm. Nesovbaatar differs from Sloanbaatar in the structure of the p4 and Infraorder incertae sedir in its smaller size, but shares with it and with Family ?Cimolomyidae Marsh, 1889 Kamptobaatar, a relatively small coronoid process that Genus Buginbaatar Kielan-Jaworowska and Sochava, flares laterally. It shares with Sloanbaatar, Kamptobaatar, 1969 Djadochtatherium and Catopsbaatar the condyle placed Type species by monotypy. Buginbaatar transaltaiensis above the occlusal level of the molars and facing dor- Kielan-Jaworowska and Sochava, 1969. sally. It differs from all the djadochtatherians in having a larger p4 with 10 cusps and 9 serrations, 8 of which Buginbaatar transaltaiensis Kielan-Jaworowska and are provided with weak ridges. It resembles Sloanbaatar Sochava, 1969 in having 4:3 cusps on ml, but differs from it in exhib- See Figure 29.14. iting an angle of 18" between the lower margin of the Holotype. PIN 3487-1 and 3487-2, incomplete maxil- dentary and the occlusal level of the molars (28' in lae with P4-M2 and both incomplete dentaries with Sloanbaatar), and 3:2 cusps on m2, rather than 2:2. The teeth. Khaichin Uul I, in the region of Biigiin Tsav, lower molars are similar in size and cusp formulae to Transaltaian Gobi, Mongolia; beds equivalent to the those of Cbulsanbaatar. The p4 resembles that of the Nemegt Formation (?early Maastrichtian). Early Cretaceous Mongolian form Arginbaatarin being Description. The dental formula is ?1/1,0/0, ?1/1,2/2, fan-shaped, but differs from it in being less vaulted, but only P4 of the upper premolars has been pre- having a smaller number of serrations with ridges, and served. The cusp formulae are: P4, 3:6:1; MI, 7:8:6; M2, being completely covered with enamel. 2:3:2; p4 has 4 cusps with ridges; ml, 5:6; and m2, 3:3. The Ion-er incisor is \.cry robust and thus similar to Order S!.~nnletrodonta Simpson, 1925b those in the Taeniolabidae, Dl;r(ior.btirtbrril~tti and Coiriiiic~irt.r The order Symmetrodonta includes the ('ntop~~birntirv..is argued b\ Kielanja\voro\\-ska and most primitive Theria, described representatives of liurum (l997j, the apparent absence of the anterior \\-hi& are rnostl\- kno\vn only from incomplete maxil- upper premolars and p3, and the enlarged upper and lae and dentaries nith teeth, although a skull and lo\ver molars \vith numerous cusps plktce Br~gi~ihil~tili.~llrnost complete skeleton of a sy~nrnetrodont outside lljadochtatheria. Bl~gir~bnntirt-nashrst assigned %bir~rg/it~ot/~t~~~irl,r~gr/ing~/~r~rspiilc~~s Hu czt ul., 1997, has to the ?(:iniolomyidae and then to the Eucosrno- heen found in the I,o\ver Cretaceous beds of Liaoning dontidae (Kielan-ja\voro\\-ska and Sochava, 1969; Pro\ince, China (Li 6.7 nl., 1995; Hu et nl., 1997). Troti~nov,1075). Hahn and Hahn (1083) estrtblished .1ccording to Hu cti11. (1997) Zbillrght~otb~riu~~~lacks the for it a subhmily Bupinbaatarinae n-ithin the more parasapittal posture of the forelirnb found in Eucosrnodontidae. The apparent lack of anterior most li\.ing therian mammals. 'The authors also con- upper premolars and a rectangular rather than arcuate cluded that archaic therians, such as s!mnletrodonts, 114 suggest that BI~~~II~NN~NI*is r1ot an eucosmodontid retained a prirniti1.e feature of non-therian mammals: (Jepsen, 1940; Sloan and \-an \'alen, 1965j, and the a finger-like prornontorium (possibly with an uncoiled elonsate multi-cusped P4 and rectangular p4 place it cochlea). Symmetrodonts, shrelv-sized ~namlnalswith outside the 'J'aeniolahidae. Its similarit!. to postcanine teeth characterized by a triangular .lfcirrscoecsris suggests affiliation nith Cimolomyidae arrangement of the three main cusps and absence of (Clemens and Kielan-Jan-oro\\-sk;~, 1479; .irchibald, an angular process in the dentary, are known from the 1982) as suggested b! Kielan-Jan-ore\\-ski1 rtnd Socha\ a Late Triassic through to the ]marsupials, placentals and their last Genus C'obtorhel-iodoil Trohrnov, 1997 cornlnon ancestor, escluding even some forms with See Fig. 29.1 5. tribosphenic molars, for esample, the 'tribotheres' of 7jpt. .rp~rit>~/)I ~liotro[~~~~.C'obiotLwvt odot~ itlfii7itu.c Butler (1078, 1090). Ilopson (1994, p. 208) coined the ('I'rolirno\, 1080). informal terrn 'holothcres': '. . . to refer to the entire Hologpc: PIS 3101 150, ~~ln~ostcomplete right dentary group of rnalnrrlals characterized by a 'reversed trian- with the last three molars and all-eoli for six remaining gles' ~nolarpattern'. The senior author (but not teeth. Hiiiiviil; Ciuchinus county, Gobi Desert, h'flJ.N.) considers this term redund~~ntand a source of \longolia; Hiiii\.iir beds (;\ptian or .llhian). confusion, as 'holotheres' are the same as Theria of Kr.f~i-t~r.drttirrr~rii11.-1fragment of a ~naxillawith h13 and Simpson (19253, b), nhile the Theria of Rone (1088) is an isolated molar, both in the PIN collections, have the same as Trihosphenida XIcKenna, 1075. \It folio\\- also been assigned to this taxon. Simpson and use the term 'l'heria (contra the opinion Desc.l-iptioir. The dental formula, known only for the of h1.J.N.)to include S\.mrnetrodonta and 'eupan- loner dentition, n-as described by 'Trofimov (1080) as: totheres'. 3, 1, 4, 5. The three main cusps on the lomr molars Zlammdls from the Xleso~o~cof \longol~'~

Figure 29.1 5. Gobiotheviodort il~/iltirus'Trohmo\,1')80, holot! pe, P1S .i101 SO, right loaer la\\ In lateral, occlusal and medial bie\vs. IIiiii\,iir beds, Hiiii\.iir. (From Trohmo\, I'>XO.)

form an angle which decreases posteriori!.: this angle all three molars that are preser\,ed in the holotype is strongly obtuse in mi, but forms almost a right angle specin~en. in 1n3; there are also t\vo small additional cuspules, An isolated petrosal bone frorn the Early anterior and posterior. Cretaceous Hiiii\ lir localit!- \ras described by LVible et Con~mi~~~ts.Guhiothiviodolz difers horn ,i~r~phir/uirin #I. (1995). :Is a result of their cladistic analysis, two ha\,ing a well developed paraconid and rnetaconid on possible allocations of this specimen were proposed. . I .tic first supported afinities with triconodontids, and Paurodontidae, but distinguished by possession of a the second ivith the therian lineage. In a subsequent comparati\.ely large talonid with a well-developed analysic (Rougier t.1 ill., 1996a), the second hypothesis, hypoconulid. i.e. therian (Prototribosphenidq afinity \\-as sup- l~ortcd. Genus .ir,ouinllr.r Dashzeveg, 1979 Qpt~sprcin:.4rguiinus kbosbajari Dashzeveg, 19 79. 'Eupantotheres' (a paraphyletic taxon, corresponding 0th~)-sprcirs. Dashzeveg (1994) also assigned the so- to the order Eupantotheria kermack and hlussctt, called Porto Pinherio molar from the Kimmeridgian 19-8) of Portugal (Krusat, 1969) to .irguinzus. COIIINICIII.~.l'lie order Eupantotheria \ras erected by Kermack and Alussett (19.58) to replace part of .4rgliinzus kbosbrfla~-iDas hze\,eg, 1070 Pantotheria hlarsh, 1880; Kerrnack and llussett See Figure 29.1 6B. retained the infraclass Pantotheria, to which they Holot~pr (aud OUIJ k)low~.cpc.rimelz). PSS 10-1 5, left assigned Sy~nmetrodontaand Eupantotheria. Iik use dentar!. A-ith p3-m2. Hiiij~ijr,Guchinus county, Gobi the term 'eupantotheres' in quotation marks, since Desert, \longolia; HGii\.iir beds (riptian or .4lhian). AlcKenna (I0;i) and Protliero (1981) have argued Drsrriptiou. 'l'he fifth lower premolar is molariform. that 'Eupantotheria' is a paraphyletic group. The paraconid and rnetaconid on m2 are much lower 'Eupantotheres' are known from the lliddle than the protoconid, the hypoconulid is prominent, an Jurassic to the Late Cretaceous. They differ frorn syni- 'entoconid' is present, and the hypoconid is indistinct. metrodonts in having an angular process on the There is no talonid hasin. dentary, lower molars with a small, hut distinct talonid and widcr upper molars. The presence of an angular Farnil!. -1rguitheriidae Dashzeveg, 1994 process links then1 to ~narnrnals with tribosphenic Genus ri)pitberiuniDashzeveg, 1094 molars, but they difer from these in lacking a proto- .4rgliitheriu1r1 cro))lptouiDashzeveg, 1994 cone on the upper molars. \lost 'eupantotheres' do not See Figure 29.1 6.4.

have 3 talonid basin on the lon-er molars, hut there is Hologpe. PSS 10-3 1, right dentar!. with pl-ml - the an incipient talonid basin in the rirpitheriidae only specimen kno~vn.Hiiiivijr, Guchinus county, (Dashzeveg, 199% see also below). Gohi Desert, Alongolia; Hiioviir beds (Alptian or klost 'eupanthothcres' are represented h!. teeth or rilbian). jaws ~vithtccth, hut Dre.rcb~mtbrriun2 from the Late D~scriptiotz. .irguitheriu)n is close to the Perarnuridae, Jurassic of Portugal is known from fairly complete frorn which it differs in having a non-molariform p5, a upper and lo~verlaws with teeth. He)~kelotberiuni,also less developed cristid obliqua and undifferentiated from the 15arly Cretaceous of Portugal (Krebs, 1991) cusps on the talonid of ml. It is distinguished frorn the and 1 ?)~rt~lestrstiom the Early Cretaceous of Argentina :imphitheriidae by the presence of an incipient (ltougier, 1003) are knoivn from skulls associated ~vith talonid basin on the rnolars and a better developed postcranial skeletons, but most 'eupantotheres' are cinplum on the labial side of ml. represented only h!. teeth or jaws with teeth. li'urelestes is regarded as a sister taxon of the Tribosphenida Legion Tribosphenida klcKenna, 1975 Alckenna, 107F (Uougier, 1093; Uo~ve,1903). Order riegialodontia Butler, 1978 Comrnetzts. .4 type of rnolar dubbed the tribosphenic Famil! -4rguimuridae Dashzeveg, 1994 molar, first occurs in Early Cretaceous Theria. The Comnretrts. rirguimuridae, according to Dashzeveg upper rnolars of the trihosphenic type differ frorn (1970, 1994), are close to .irnphitheriidae and those of 'eupantotheres' in that they are wider and Mammals from the Mesozoic of Mongolia

conid, though only two of these - the hypoconid and the hypoconulid - occur in some early forms. Tribosphenic molars are characteristic of Cretaceous and most early Tertiary therians, as well as of some extant therians. Kermack et al., (1965) described Aegialodon dawsoni from the lower Wealden (Valanginian) of southeastern England, based on a single tiny tribosphenic lower molar with a small, but basined talonid. This tooth was believed at that time to be the oldest known tribosphenic molar and Aegialodon was regarded by these authors as an ancestor of all mammals with tribosphenic molars. Subsequently, Kermack (1967) erected the family Aegialodontidae for this genus. Dashzeveg (1975) described another aegialodontid lower molar from the Aptian or Albian of Hoovor (Guchinus county) in Mongolia, and named it Kielantherium gobiensis. Butler (1978) erected the order Aegialodontia (including Aegialodontidae, Kermac- kiidae, Deltatheridiidae and, tentatively, Potamotelses) within his infraclass Tribotheria. Fox (1980) excluded the Kermackiidae and included Picopsidae in the Aegialodontia, while Kielan-Jaworowska and Nesov (1990) excluded the Deltatheridiidae, arguing that Figure 29.1 6. Arguitbwium cromptoni Dashzeveg, 1994, deltatheroidans are metatherians. Subsequently, holotype, PSS 10-31, right lower jaw with p+ml in (A) Butler (1990) accepted the metatherian nature of the lingual and occlusal views. Avguimus kbosbajariDashzeveg, 1979, holotype, PSS 10-15, left lower jaw with p3-m2 in (B) Deltatheroida, withdrew his infraclass Tribotheria lingual and occlusal views. (From Dashzeveg, 1994.) and restricted Aegialodontia to Aegialodon and Kielantherium, an action tentatively accepted here.

Family Aegialodontidae Kermack, 1967 possess a lingual cusp named the protocone (this is Genus Kielantberium Dashzeveg, 1975 absent, apparently with one exception, in 'eupan- Type species by monotypy. Kielantheritlm gobiensis totheres'). The three main cusps of the tribosphenic Dashzeveg, 1975. upper molar are arranged in a triangle (trigon) and are called the protocone, metacone and paracone. There Kielantbenkm gobiensis Dashzeveg, 1975 are also accessory cusps (styles) situated on the labial See Figure 29.1 7. margin of the triangular upper molar. The tribos- Holotype. PSS 104, right ?m2. Hoovor, Guchinus phenic lower molars differ from those of 'eupan- county, Gobi Desert, Mongolia; Hoovor beds (Aptian totheres' (except for Arguitherium) in having a talonid or Albian). basin, which received the protocone of the upper Referred material. PSS 10-16, an incomplete right molar. On the margin of the talonid there are usually dentary with four molars, alveoli or roots of four three cusps: a hypoconid, a hypoconulid and an ento- double-rooted premolars, and one broken alveolus for Z. KIELAN-JAWOROWSKA etal.

Figure 29.17. KielantberiumgobiensirDashzeveg, 1975, PSS 10-16, right incomplete lower jaw with four molars and eight alveoli or roots of four double-rooted premolars and one broken alveolus for one more premolar or canine in (A) labial and (B) medial view. X 6. (From Dashzeveg and Kielan-Jaworowska, 1984). another premolar or the canine (Dashzeveg and different from those of Prokennalestes, Kielantherium (of Kielan-Jaworowska, 1984). which only the lower molars are known), and Description. In Kielantherium the trigonid is larger than Deltatb~dium. the talonid, the protoconid is the highest cusp, and the paraconid is higher than the metaconid, as is charac- Metatherian-eutherian dichotomy teristic of the Deltatheroida. The talonid basin is Comments. For many years it has been generally narrow, with a hypoconid and hypoconulid; the ento- accepted that metatherians and eutherians conid is not developed. differentiated from a common ancestor during the Comments. The Aegialodontia are known only from Early Cretaceous, and that metatherians diversified in lower molars. The oldest tribosphenic molar is pos- North or South America, while eutherians diversified sibly a talonid from the Purbeck Limestone Group in Asia. It was presumed that this vicariance resulted (?early Barriasian) of England (Sigogneau-Russell and from the appearance of marine barriers between the Ensom, 1994). Aegialodon (Kermack et al., 1965) from main land-masses, which restricted intercontinental the Valanginian of Sussex is younger. Similarly exchange (e.g., Lillegraven, 1969, 1974). At that time it Tribotherium africanum and other 'tribotheres' from the was also believed that metatherians did not reach Asia. Berriasian of Morocco (Sigogneau-Russell, 199 1b, However, palaeontological discoveries of subsequent 1995) may be slightly younger. The upper, and tenta- years have challenged this hypothesis. tively assigned lower molars, of Tribotherium are A family of carnivorous therians, the Deltatheri- \Ia~nlnalsfrom the \lesozoic of \Ionpolia

diidae Gregorh- and Simpson, 1026 (see belo\v), and Kielan-Ja\\oro\\sk~~( 10021, and *froh~novand knoivn originally from the Late C;reraceous of .\sia, Szalay (l004~,Yeso\ (1 997) and liougier cJt it/. (1 008), \vas fin a long rime reyarded as an important group of but cu~itriiC;ifelli (1003). placental carnivores. Ho\\e\er, Butler and Kielan- Deltiltheroida are an order of relati\.ely large (by Ja\voroivsLa (1073) sho\ved that this group has a mar- \lesozoic standards], carrli\ orous mammals, the skull supial-like postcanine dental ti~rmula..\ccordingl\., Ienpth of \\hich ranges I)et\\-een 40 and 70 mm. Kielan-Ja\voro\vska and Yeso\ (1990) assipned the Ueltatheroidi~~n\retain se\.eral characters that are Deltathcroida Kielan;la\\oro\vska, 1082 to the plesiomorphic for therians. For esilmple, the nasals are XIetatheria. Szalay and Trohrno\ (1996) described esp;lnded posteriorly and there is a long jugal that the skl~lland postcranial skeleton of a metatherian, contributes to the plenoid fossa. l'he!, also ha\,e an ,-l.ri~~tl)~~rin~~iI~~JJ/)~T/I;.~, fro~n the Lare Cretaceous of incipient alicphenoid t~uila,a feature regarded t)y kIongolia. Kieliln-Ja\\oro\vska and heso\ (1000)as 3 metatherian 'I'he oldest kno\vn marsupials are Ceno~nanianin trait, thonsh it is absent in the South .\rnerican ase (Cifelli and Laton, lOST), the deltatheroidans cur- Palaeocene marsupials Piic~ildtdpLy,r and .Ili!yrdt:rtt~.r renrlh. date tiom the late .l'uronian I k:aton and Cifelli, (\I~iizo~~,1004). 1088), \vliile the oldest eutheri~lnsare from the :late LIarsupial characters (Iiouyier t~ ill., 1008) include: ,\prian or ?early .\lhian of \Ionpolia (Kielan- a premasilla \vith a posteriori\ directed process that Ja\voro\vska and DashzeIey, 108'4). 'These and other reaches the al\.colus for the canine; and a dentar! \vith data, discussed under .\eyialodontia, supgest that the a shelf-like mcdially directed process. 'I'he petrosal is m~lrsupial-placentill dichotomy occurred earlier than similar to those attrihured to metatherians tiom the pre\.iously thought, possibl!. during the latest Jurassic. Late C;reraceous of Sorth .\merica (\Tible, 1000) 311d sho\\s t\\o nrajor metatherian s\,napomorphies: (I) a

'1'11 eri a i~ii.ca~-tiicasc,iii~. marked reduction or absence oi the stapedial arterial Genus Hy~tl)e~~~iiiiiii,/(;regor\. and Sirnpson, 1026 s\-stem; and (2) (1 s~nall,horizontally directed prootic Type .yic~cica.r421 NIOUO~J~IJ~.H~~otht~~~idiiii~i ii/~ilso~iiGre~ory canal connected to the postylenoid ~enoussystem. ancl Sirnpson, 1026. The dental formula: 4 -3, 1 1, 3 3, 4 4 (as esrahlished for Dc~itiitl~c~ridiiii~r),i.4 marhupial-like and there is a

H~~othc~iiiiii~rriluh.~.u~ii Gregor!. and Simpson, 1026 sharp morpl~oloyicalbreak het\veen tlie molars and 1lolot)pr.. .\\IN tl 2 1702, a !ingle, damaped rostrum prernolar~,I\-hich are not molariform, as is characteris- \vith anterior parts of both dentarics. Bayan Zag, Gobi tic of metatherians. The most disti~icti\.esimilarity Desert, XIonpolia; Djadokhta Formation ('earl! bet\veen Dcdtiithc~iiiiiiw and li\ inp marsupials is the Campanian). tooth replacement prittern, c1iar;icterized by rcplace-

Dc~.sc~ripti~~~i//I/// c/ii~ii~ic,~it.s.H. i/oh.ro~iiis 1er\, poorl\. men[ of a single tooth (last premolar). Unlike marsu- known. It has lar~eupper and Io~vcrcanines and three pials, the h\.poconulid and entoconid on tlie lo\ver premolars, \vliicli might indicate deltatheroidan molars lire not approsimated. I'he upper molar st\.lar affinities (see t)elo\v). .is the nurnher of molars and shelf is, relativel\- speaking, the \videst am on^ trihos- their occlusal surfaces are not kno\vn, \ve prefer to phenid ~iiamrnals. classif!. it as 'Tlieri:~ilicc~/-tnt- .rtvii.r. Sti,ctigi-~phii.ii~iii~e~o~~~ipkird i-iliizca. Late (:1-eruceous of the Northern Hemicphere (Cregor!. and Simpson, Infraclass \[eratheria I Iusle\., 18HO 1026; Fox, 10-4; Kielan-Ja\voro\vskii, 10752; Kielan- Order Deltatlieroid~iKielan-Ja\\oro\vskii, 1 082 Ja\\oro\\.ska and Yeso\., 1000; \larshall and Kielan- Co~~irrrc~~it.r.\ie t;)llo\v Kielan-ja\voro\vskii and Seco! ]3\voro\\skii, 1001; see alqo Ciklli, 1003, for re\.iea.). (1000) in assigning Delratheroida Kielan;Ta\\oro\vskii, Co111111c~lctoil .~:j~~tc'i~~iitic.r.Kiela ~i;Ta\\oro\vskii and 1082, to the hIerarheria, in apreeliient \vith \Iilrshall \eso\- ( 1000) di\-ided the order Delratheroida Kiel~in- Jaworowska, 1982, into two famillies. Deltatheridiidae Holotype. A\MNH 21705, a damaged rostrum asso- Gregory and Simpson, 1926, and Deltatheroididae ciated with both dentaries. Bayan Lag, Gobi Desert, Kielan-Jaworowska and Nesov, 1990. Deltatheridiidae 3longolia; Djadokhta Formation (?early Campanian). are characterized by lack of palatal vacuities and three R'rred material. Five incomplete skulls from the upper molars (rather than the usual four), w-hile Baruungoyot Formation and Red beds of IIermiin Deltatheroididae are characterized by the presence of Tsav in the ZPAiL collection, several skulls from palatal vacuities and four upper molars. Rougier etal. Lkhaa Tolgod in the PSS collection. (1998) demonstrated on the basis of better preserved Description. Deltatheridiul12 pretrituberculare is a rela- material of Deltatberidium from C'khaa Tolgod in tively small carnivorous main~nal(skull length about Mongolia that this genus, and in consequence 40 mm long), with shortened snout, no palatal vacui- Deltatheridiidae, have four upper molars. Thus the ties, and a lacrimal with a large hcial wing. '['he stylar only difference between the two families would be the shelf on the molars is very large, with a deep presence or absence of palatal vacuities. .is in other ectoflexus, paracone and metacone placed in the groups of mammals, however, the presence of palatal middle of the tooth width, and large, convex conules. vacuities is a generic, rather than family character, and The protocone is small and low. The pl is single- we regard Deltatheroididae Kielan-Jaworo~vskaand rooted, while p2 and p3 are double-rooted with basal Nesov, 1990, as a junior subjective synonym of cusps. In lower molars the protoconid is tall, the meta- Deltatheridiidae Gregory and Simpson, 1926. conid is smaller than the paraconid, and the talonid is Nesov (1985) proposed Sulestinae as a subfamily of transversely narrolv. the Deltatheridiidae, but SIcKenna and Bell (1997) Kielan-Jaworowska (1975a) erected a new subspe- synonymized this subfamily with Deltatheridiidae cies D. pretritubercttlare tardu~rz,based on five specimens Gregory and Sirnpson, 1926. .is we have not found from the Baruungoyot Formation and Red beds of characters that would differentiate the Sulestinae and Hermiin Tsav. &isdemonstrated by Rougier et al. a nominal subfamily Deltatheridiinae at the subfamily (1998), the apparent difirences l~et~veenD. p. tardttm level, we follow McKenna and Bell in this respect. and the nominal subspecies are due to the state of preservation and do not merit distinction at the sub- Family Deltatheridiidae Gregory and Simpson, 1926 species level. Included genera. Deltatberidium Gregory and Simpson, 1926; Ddtatberoides Gregory and Simpson, 1926; Genus Deltatheroides Gregory and Simpson, 1926 Sulesttlr Nesov, 1985; Deltatberoides-like mammals (Fox, Type species hy ~20110tyy9~.!.eltatheroides cretacicus 1971); and a deltatheroidan skull from Guriliin Tsav Gregory and Sirnpson, 1926 (Anonymous, 1983; Szalay and Trofimov, 1996, fig. 22). Strutigrapbic and geographical range. Late Cretaceous of Deltatheroides cretaczcttsGregory and Simpson, 1926 Mongolia and North America. Holotypc .ih'INH 2 1700, a damaged snout. Bayan Zag, Gobi Desert, h'longolia; Djadokhta Formation (?early Genus Deltatberidium Gregory and Simpson, 1926 Campanian). Type species by monotypy. Deltatberidium pretrituberculare Refirred material. ZPAL IZIghl-1/29, a left dentary Gregory and Simpson, 1926. from the same formation and locality as the holotype. De.rcriptiotz. The skull and dentition in the holotype DeltatberidiumpretrituberculareGregory and Simpson, specimen are badly damaged. Individual teeth in ZPAL 1926 h1ghI-1/29 are about 1.2-1.3.5 times greater than those See Figure 29.18. of Deltatberidium pretrituberculare ZP.4 I, MgM/-119 1 Synonym. Deltatberidiumpretritubercularetardum Kielan- (see Kielan-Jaworowska, 1975a, table I), but do not Jaworowska, 1975. differ much in morphology. Owing to the poor state of Mammals from the Mesozoic of Mongolia

Figure 29.18. Deltathe~idiump~e~~tuberculareGregoryand Simpson, 1926, PSS-MAE 133, rostrum and dentaries. Palate in occlusal view and dentaries in oblique dorsal view (A). Rostrum in dorsal view and dentaries in ventral oblique view, showing the inflected angle (B). X 2.2 (From Novacek etai, 1997.) Abbreviations: an, angle; M4, fourth molar; pm, premaxilla.

preservation of the holotype specimen it cannot be Asiatherium reshetovi Trofimov and Szalay, 1994 stated, with any certainty, whether the palatal vacui- See Figure 29.19. ties, which are present in the Guriliin Tsav skull, occur Holotype (and only known specimen). PIN 3907, a crushed also in Deltatheroides. The differences between the two skull with both dentaries and an almost complete post- Mongolian deltatheroidan genera Deltathe~dum and cranial skeleton. ~iidenSair, Gobi Desert, beds equiva- Deltatheroides are not clear, and in the future it may be lent to the Baruungoyot Formation (?lateCampanian). shown that the two genera are congeneric. Description. A. reshetovi has three premolars and four Comments. The beautifully preserved, almost com- molars with a sharp morphological break between the plete, so-called deltatheroidan skull from Guriliin last premolar and first molar. The stylar cusps are Tsav (Anonymous, 1983; Kielan-Jaworowska and poorly developed and the conules and pre- and post- Nesov, 1990; Szalay and Trofimov, 1996, fig. 22) from cingula are present. Szalay and Trofimov (1996, p. 474) beds corresponding to the Nemegt Formation awaits stated: 'the closely twinned hypoconulid and ento- description. It is the largest known deltatheroidan conid, correlated with a (relative) hypertrophy of the with distinct palatal vacuities. metacone, an alisphenoid component to the bulla (possibly an independently derived trait), oval Order Asiadelphia Trofimov and Szalay, 1994 (not elliptical) fenestra vestibuli, and an elliptical Family Asiatheriidae Trofimov and Szalay, 1994 fenestra cochleae, along with other unmistakenly Genus Asiatherium Trofimov and Szalay, 1994 marsupial-like characters (and therian as well as pre- Type species by monotypy. Asiatherium reshetovi Trofimov therian) postcranial taxonomic properties, all attest and Szalay, 1994. the noneutherian status of Asiatherium.' Further analy- Z. KIELAN-JAWOROWSKA etal.

Infraclass Eutheria Gill, 1872 Comments. Eutherians are known from both Early and Late Cretaceous assemblages of Mongolia. The former represent possibly the oldest record of the group, but the material representing these forms consists largely of teeth, or jaw fragments with teeth. By contrast, the Late Cretaceous eutherians are represented by spectacular skulls and skeletons. Despite this abundance of excellent material, the relationship of these taxa to later eutherian orders is problematic. This is in part due to the predominance of morphological traits that suggest the primitive eutherian condition. It is well known that the epipubic (marsupial) bones, projecting anteriorly from the pelvic girdle into the abdominal region in monotremes and marsupials, are absent from extant eutherians. The epipubic bones occur also in tritylodontids and in some extinct groups of early mammals: multituberculates (Kielan- Jaworowska 1969b) and symmetrodonts (Hu et al. 1997). Kielan-Jaworowska (197Sc) demonstrated that the Late Cretaceous eutherian Barunlestes (family Zalambdalestidae) has a triangular fossa on the anterior margin of the acetabular branch of the pubic bone, which she interpreted as the attachment area for Figure 29.1 9. Asiatben'um resbetoviTrofimov and Szalay, 1994, the epipubic bone. She suggested that epipubic bones holotype, PIN 3907, drawing of the palatal view of the skull might have been present in all early mammals and from beds equivalent in age to the Baruungoyot Formation, ~iidenSair, Southern Mongolia. (From Trofimov and Szalay, their disappearance in the Tertiary Eutheria may be 1994.) Scale bar, 5 mm. connected with the gradual evolution of a prolonged internal gestation period. Kielan-Jaworowska's pre- diction has been confirmed by the discovery of epipu- sis, including comparisons with new deltatheroidan bic bones in symmetrodonts (Hu et al. 1997) and material from Ukhaa Tolgod is required. especially by the discovery by Novacek etal. (1997) of Comments. Aver'yanov and Kielan-Jaworowska (1999) epipubic bones in two lineages of Late Cretaceous described additional material of MarsasiaNesov, 1997, eutherians from Mongolia: a zalambdalestid - cf. from the Coniacian Bissekty Formation of Zalambdalestes and an asioryctid, Ukbaatberium nessovi Uzbekistan, and assigned it tentatively to Asiadelphia. Novacek etal., 1997. They suggested that the phylogenetic position of The question of which is the oldest eutherian Marsasia might lie between the Albian form Kokopellia mammal is still debated. Ausktribospbenos, allegedly an (Cifelli and Muizon, 1997) and the Campanian form Early Cretaceous placental from Australia (Rich et al., Asiatherium, thus supporting Cifelli and Muizon's con- 1997), is, in our opinion, not a eutherian (see also clusion regarding the marsupial affinities of Kielan-Jaworowska et al., 1998). Prokennalestes, Asiatherium. described below, is a likely candidate and is contempo- \Iamm;lls from the \lesozoic of \lonpolia raneous \vith Slii~/ghtt.~-icifrom the .ilhian of 'l'ex;ls order I-'roteuthcria, and \\ere folio\\-ed in this I]!. (Alarshall and Kielan-!a\\-oro\vsk;~, 1002, but see also Sipogneau-Kussell c~iii.(1002). Butler, 1978, 1900), and .Ifoii/iiiiii/c:i./c:c from the So\aceh c2t N/. (1')');) placed .ii-io~:yc.tc>.i-and a new Cloverl! Formation (.-\ptian or .-\lbianj, see Cifelli closel!. related yenns, L ~/IIII,in the ( 1090). .\sior\ctidae Iaonicrol>idac, in thc superorder systematic arrangements proposed h!- e.y., Carroll, Lel~tictid;lAIclateCretaceous \lonyolian genera Genus Pi-oki~iiiiii1c~stl:i.Kielan_l;l\\-oro\\~sk:~ and ki~~r~ruic~stt~sand d.t.rio~:)'ctl:r (assigned to Palaeor!-ctinaej Da.;hze\.ep, I080 as the earliest ernorheres. He also referred to elll-l! '[jpc .r/)c,i ic2.1: Piok~,ii~ic~/c~.itc~.iti-~!/ii~io;.i Kielan -!a\voro\vsk a ernorheres the Late Cretaceous \lonpolian zalaml>cl;l- ;lnd Ililsh~e\ep. 10SO. Icstids, coeval ivith anagalida and se\eral other groups 0tL1c.i- .r/~i'"cic.-. Pi-okc~iiiiiiic~i-t1,i-iiii~ini- ICielan-!a\voro\vs!,i> of earl!. eutheri;lns. ~lntlD~lshze\.ey. IOSO. Kielan-Ja\voro\vski~(1081 ) erected Kennalehtidae to include K~.IIIIN/~..I-~~,Jand ten tati\-el!. 'Pi-oki~ii~iii/c~.i/~~~' Pink~~iiiiiiic~.i./c~.~~ti.ofii~io;>i Kielan:la\voro\\.sk;~ and (cited at that ti~neas a ~toiiit~iiii~~d~~iii), ilnd ascigned her I)sshze\ ep, 1080 new famil!. to Protcutherin Konler. 1066. She assiynecl See Figure 29.20. to the same sut~orderthc I-'alaeor~ctidae,and erected Iloiotlpc.. PSS 10-6, pohterior part of the right dentary ivithin it .\sior\ctinae to include the sole genus \\-it11 coronoid and cond\.lar procecses, m2 and m.?. .-l.riot~yctc~: Nesov (108;) erected the auborder Hiiiiliir, (;ucliinl~s count!, Col~illescrt, llonpolia; hlisotheridia (within Protentheria), and Seso\- czt #I. Hiiii\ iir beds ( \ptian or .\ll,ian 1. (l00-C) assigned the Znlaml~dalestidae to this tilson. Rc~/c~~i-i-c~iliiiiitc~i-iiii.Ciglltccn dentnrics 311d nlasillile \virh and was folloived in this respect hi. Sese)\. r I()()-). In teeth in the PSS collection ~lntla large number of 11s this last paper Seso\ placed I

Kielan-Jaivoroivsk:~and llach~e\eg c l OSY r clascitied ectimilrcd hknll Ienprh l~~in~14-1- Inn). It has 3 labial Proke~rtinlertcsivirhin Orlecridile. supertimily Kennale- rn;llldibulnr ti)ranlc~land remnants of rhc coronoid stoidea (as a new rank assipned to Kennalestidae), bone and the \lechelia~lgre)o\e. 'l'here are ti\,? pre- 2. KIELAN-JAWOROWSKA etal.

Prokennalestes minor Kielan-Jaworowska and Dashzeveg, 1989 Holotype. PSS 10-7a, fragment of the posterior part of the left dentary with m2; locality and horizon as for P. trojmov i. Refiredmaterial. Eighteen dentaries and maxillae with teeth in the PSS collection and a large number of as yet undescribed specimens in the PIN collection. Description. P. minor differs from P. trojmovi in being distinctly smaller and in that the Meckelian groove is only slightly flexed. Comment. As noted by Kielan-Jaworowska and Dashzeveg (1989; see also Sigogneau-Russell et al., 1992), P. trojmovi and P. minor differ only in size and may be sexual morphs of the same species.

Eutheria gen. et sp. indet. Material. In the PSS collections from Hoovor there is a heavily worn undescribed lower molar 2.8 mm long. This specimen shows that in addition to the minute Prokennalestes, another, somewhat larger eutherian taxon, occurred in this assemblage.

Figure 29.20. Prokennalestes tmjimovi Kielan-Jaworowska and Family Kennalestidae Kielan-Jaworowska, 1981 Dashzeveg, 1989, reconstruction of the dentition. P+M3 in See Figures 29.21 and 29.22.B. (A) occlusal and (B) labial view; pS-m3 in (C) occlusal, (D) Genus Kennalestes Kielan-Jaworowska, 1969 lingual and (E) labial view; m2 in (F) anterior and (G) Type species by monotypy. Kennalestes gobiensis Kielan- posterior view. (From Kielan-Jaworowska and Dashzeveg, 1989.) Jaworowska, 1969.

Kennalestesgobiensis Kielan-Jaworowska, 1969 Holotype. ZPAL MgM-113, anterior part of the skull molars and three molars. PS is semimolariform associated with both dentaries. Bayan Zag, Gobi without a metacone. The molars have three cusps in Desert, Mongolia; Djadokhta Formation (?early the parastylar region: the paracone is larger than the Campanian). metacone, the conules are unwinged, and there is no R.ferred material. Five fragmentary skulls and one pre- and postcingula. In the lower molars there is a 3- complete juvenile skull in the ZPAL collection; except cusped talonid that is narrower than the trigonid for an atlas the postcranial skeleton is not known. (Figure 29.20). The dental formula in these speci- Description. The skull length of adult individuals is mens supports the notion that primitively eutherians about 26 mm. The dental formula is 4/3,1/14/4,3/3, had five premolars (McKenna, 1975; Novacek, but, apparently, there are five premolars in juvenile 1986a). specimens. The upper and lower canines are double- rooted. P1 and P2 are small with minute diastemae in front, behind and between them. P3 is the strongest tooth in the postcanine series, while P4 is partly Mammals from the Mesozoic of Mongolia

em- '--

u e@@p Imm -_ C

Figure 29.2 1. Kennalestesgobienszs Kielan-Jaworowska, 1969. Upper canine and cheek teeth in (A) occlusal and (B) labial views. Lower canine and cheek teeth in (C) occlusal view. Lower dentition in (D) labial and (E) lingual views. (From Kielan-Jaworowska, 1969a.j molariform, but has only an incipient metacone. The and the problem is in need of further study. Kennalestes molars have a large parastylar area with three cusps has a number of features, including the conservative and the preparastyle characteristic of Prokennalestes is construction of its tympanic region, and the presence present. The conules are winged and there are pre- of five premolars in the dentaries of some juvenile indi- and postcingula. The dentary is slender and the viduals (see McKenna, 1975; Kielan-Jaworowska et al., angular process is slightly inflected. The snout is 1979), that bear on arguments concerning the transfor- tubular and the nasals are expanded posteriorly. The mation of important mammalian features. structure of the basicranial region is discussed below together with the description of Asioryctes. Family Asioryctidae Kielan-Jaworowska, 198 1 (new Comments. In terms of its cranial anatomy Kennalestesis a rank) very primitive Mongolian Cretaceous mammal. Its sug- Genus Asioryctes Kielan-Jaworowska, 1975b gested alliance with North American Cretaceous and See Figures 29.22A and 29.23. Early Tertiary Leptictidae (Kielan-Jaworowska et al., Type species by monotypy. Asioryctes nemegetensk Kielan- 1979) has been questioned (Fox, 1976; Novacek, 1986b), Jaworowska, l975b.

Mammals from the Mesozoic of Mongolia

Figure 29.23. Skull of Asioryctesnemegetenscs Kielan-Jaworowska 1975, ZPAL MgM-1\98, in right lateral view. Red beds of Hermiin Tsav, Hermiin Tsav 11, Gobi Desert. X4. (From Kielan-Jaworowska, 1975b.)

Asioryctes nemegetensis Kielan-Jaworowska, 1975 meets the maxilla with a sigmoid suture. The coronoid Holotype. ZPAL MgM-1/56, almost complete skull process is larger than in Kennalestes and the angular with both dentaries in occlusion, atlas and axis. process is similarly inflected. Nemegt, Nemegt Basin, Gobi Desert, Mongolia; The postcranial skeleton, which is partly known, Baruungoyot Formation (?late Campanian). shows that the pollex and hallux were not opposable, R.ferreed material. Ten specimens including skulls or which together with sedimentological data indicate fragmentary skulls with dentaries, and, in one case, terrestrial (not scansorial) habits (Kielan-Jaworowska, associated with an incomplete postcranial skeleton 1977). (Kielan-Jaworowska, 1975b, 1977, 1981) in the ZPAL Comments. Kielan-Jaworowska (1981) regarded the collection from the localities of Nemegt, Khulsan and following features of the skull structure, characteristic Hermiin Tsav 11, in the Gobi Desert. for both Kennalestes and Asioryctes, as symplesiomor- Description. Skull length is about 30 mm. The dental phic therian character states: inclination of the occipi- formula is 514, 1/1,4/4, 313. In lateral view the teeth tal plate forwards from the condyles; development of a show the same arrangement as in Kennalestes, but the basisphenoid wing homologous to the basipterygoid molars differ considerably in being strongly elongated process; a foramen rotundum that is confluent with the transversely. On the molars there is no pre- and post- sphenorbital fissure; an ectotympanic inclined 45' to cingula, the paracone and metacone are situated more the horizontal; medial internal carotid and stapedial labially than in Kennalestes and are connate at their arteries present; no entotympanic; a long jugal; a sub- bases. The metacone is much shorter than the para- squamosal foramen; no paroccipital process, and a cone and the paraconule is larger than the metaconule. medial inflection of the angular process. The lower molars differ from those in Kennalestes in Asioryctes has been assigned to the Asioryctinae having a smaller paraconid and a trigonid that is within Palaeoryctidae (Kielan-Jaworowska, 1975b, shorter in relation to the talonid. The jugal is deeper 1981; Kielan-Jaworowska et al., 1979), a family allied than in Kennalestes and its anterior portion is deep and by some with soricomorph insectivorans (Lillegraven ~tnl.,1981). Nonetheless, as noted abol-e,many aspects Order Anagalida Szalay and hlcKenna, 1971 of ,4siovycte.r, most notably the postcranial skeleton, are Family Zalambdalestidae Gregory and Simpson, 1926 extremely primitive (Kielan-Jaworo~vska,1977) and Gt'i2t'i,n iizcllldt~d. Znltztnbdnlrstrs Gregory and Simpson, even defy a clear association with other selected 1926, Bnvu1zleste.r Kielan-Ja~vorowska, 1975b, Alyinlestes eutherian clades (Ko~.acek,1980). X1oreo1-er, se~.eral A\ver'yanov and Nesov, 1095. features of the anterior tympanic roof and the shape of the postglenoid process do not (cotzti,~ Kielan- Genus Znlanzbdaltstt.s Gregorv 2nd S~mpson,1926 Jaworowska, 1981) necessarily point to a close rela- Qpe specres ly ~noirot~pjLalnmbdalestes leebe2 Gregorv tionship with Early Tertiary North ;\merican and Simpson, 1926 palaeoryctids (hlacPhee and Novacek, 1993). Znlainbdulesteslech~iGregoryand Simpson, 1926 Genus C khnathevzutn No~acekrtal, 1997 See Figures 29.22D and 29.25. Type specles (ly moizotypy C kbnathrnum rressoel No1 ace!,, Holoppr. AIINH 2 1708, a damaged skull with a large Kougier, Wible, McKenna, Dashze~eg,and Horo~itz, part of the left dentary. Bayan Zag, Gobi Desert, 1997 llongolia; Djadokhta Formation (?early Campanian). Rt;f?vved ~zatcvial.Three specimens in the AMNI-I, at L'khantht.vitiv~itrssori h'ovacek ~tal.,109; least seven in the PSS, collected by recent h'l..\E Holodvzatevial. PSS-hI.\E 103-1 06, skulls and skele- skeleton. tons found in association with the holotype; PSS- Drscviptio~z. The skull (Kielan-Jan-orowska 1984a) is hlAE 110, skull with lower jaws articulated, but up to 50 mm long, strongly constricted in front of PI, lacking anterior snout and anterior mandible; PSS- and elongated into a very long, narrow snout. The hfL\E 11 1, complete skull with lower ja~vsin articula- zygoniatic arches are slender and strongly expanded tion. laterally, and the lanibdoidal crests are prominent. Dcrcviptiotz. C7khnnthrviumis united with K~trita1rstt.sand The dental formula is: 313, 1 /I, 414, 313.11 was appar- .4.rioq1cte.r in the Asioryctitheria by the following char- ently small, 12 enlarged, caniniform, and 13 small, with acters: drainage for the postglenoid vein within rather a long diastema between 13 and C. The upper canine is than posterior to the glenoid buttress which is devel- very large, double-rooted, and placed some distance oped medially into an entoglenoid process; distinct behind the premaxillary-1naxi1la-y suture. P1 and P2 interfenestral ridge on the promontorium; and large are small, P3 is the tallest of all the teeth with a spur- piriform fenestra. L3haatbeviun1 and dsiovjctes both like protocone, while P4 has a protocone developed as have: P (second upper premolar) smaller than PI; in molars, but no metacone. The upper molars lack upper rnolars rnorc strongly elongated transversely, cingula and are strongly elongated transversely with lacking pre- and postcingula; occipital exposure of the incipient conules and a small stylar shelf. h13 is very mastoid rectangular in outline (triangular in small with respect to XI1 and M2. The il is very large Kef2ttalt.stc.s);and a large lower foramen on the occipital and procumbent, but procumbency decreases between exposure of tbe mastoid. C'khaatbt,vitrnl differs from i2 and p2. The c is single-rooted. The p4 has a three- A.riovyctes in having an enlarged upper canine with a cusped trigonid and a talonid without basin. 'The lower single root (smaller and double-rooted in the latter); a rnolars have trigonids narrower than the talonids, and less robust P3 with a less salient paracone; only two the paraconid and rnetaconid are connate at their mental foramina in the dentary; and a smaller facial bases. The paraconid is very small, the protoconid is process of the lacrimal. See Figure 29.24. the highest, and the talonid is strongly basined. Mammals from the Mesozoic of Mongolia

Figure 29.24. Dentition of Ukbaatben'um nessovi(PSS-MAE 102). Occlusal (top) and labial (middle) views of the left upper dentition; 11-5, C, P1-4, M1-3. Labial view of the lower dentition (bottom); il4,c, pl-4, ml-3. Lower dentition is a composite .'-&I-. ..:-I.-:, 7 .-3 - --J&L-I-CA:" -, A --,I-, 2 of the right il-3 and c, and the left i4, pl4, and ml-3.

The structure of the braincase and postcranial addition, the dentary is deeper and there is a higher skeleton will be discussed together with Barunlestes. coronoid process with a powerful coronoid crest, equipped with a knob-like projection and a medial Genus Barunlestes Kielan-Jaworowska, 1975b prominence. Type species by monotypy. Barunlestes butleri Kielan- Although Zalambdalestes and Barunlestes differ in Jaworowska, 1975b. dental formulae and the shape of the skull and dentary, their braincase structure is closely similar Barunlestes butleri Kielan-Jaworowska, 197Sb (Kielan-Jaworowska and Trofimov, 1980; Kielan- See Figures 29.22C and 29.26. Jaworowska, 1984a; Novacek et al., in prep.). The Holotype. ZPAL MgM-1/77, a damaged skull with both zalambdalestid braincase (Figure 29.26) is more dentaries and a large part of the postcranial skeleton. inflated and the mesocranial region is shorter than in Khulsan, Nemegt Basin, Gobi Desert, Mongolia; Kennalestes and Asioryctes. The occipital plate is Baruungoyot Formation (?late Campanian). inclined forwards from the condyles, the maxilla Referred material. Five specimens in the ZPAL, one in extends backwards along the choanae, and the pre- the PIN and one in the PSS collections, representing sphenoid has a prominent median process. There is a incomplete skulls. large pterygoid process of the basisphenoid and the Description. Barunlestes differs from Zalambdalestes in postglenoid process extends only along the medial having a shorter and somewhat more robust skull part of the cupola-like glenoid fossa. The promontor- (about 35 mm long), a single-rooted upper canine, and ium is flattened and lacks definite grooves for trans- only three upper premolars (the P2 is lacking). In promontorian arteries, the carotid foramen is placed Z. KIELAN-JAWOROWSKA etal.

Figure 29.25. Zalambdalestesle~heiGregory and Simpson, 1926. Upper canine and cheek teeth in (A) occlusal and (B) labial views. Lower canine and cheek teeth in (C) occlusal, (D) labial and (E) lingual views. X 6. (From Kielan-Jaworowska, 1969a.)

medially, and there is a foramen arteriae stapediae and which are preserved in Zalambdalestes and parts in sulcus arteriae stapediae, but no sulcus arteriae pro- Barunlestes, was probably similar in all zalambdalestids montorii. This arrangement shows that the carotid and has been reconstructed on evidence of both arteries, the main channels supplying blood to the genera (Kielan-Jaworowska, 1978). This skeleton brain, entered the skull along the midline rather than shows a mosaic of primitive and advanced characters. at the sides, as they do in most living mammals. The axis has a very long spinous process, but the tho- The postcranial skeleton (Figure 29.27), parts of racic vertebrae bear only short spinous processes. The Mammals from the Mesozoic of Mongolia

\ F. NERVI FEN. COCHLEAE HYPOGUlSSI

5 rnrn I I

Figure 29.26. Barunlestes butleri Kielan-Jaworowska, 1975, PIN 3 142-701, ventral view of the braincase. Red beds of Hermiin Tsav, Hermiin Tsav 11, Gobi Desert. Abbreviations: F., foramen; FEN., fenestra; PROC, process. (From Kielan-Jaworowska and Trofimov, 1980.) Z. KIELAN-JAWOROWSKA etal.

Figure 29.2 7. Zalambdalestes lechei Gregory and Simpson, 1926. Reconstruction of the postcranial skeleton, partly based on Bavunlestes. (From Kielan-Jaworowska, 1978.)

tibia and fibula are strongly fused, and a calcaneal and cerebral hemispheres widely separated posteri- fibular facet is lacking, but the tibia1 trochlea on the orly. There is a large midbrain exposure on the dorsal astragalus is well developed. The hind limbs, espe- side and a comparatively short and wide cerebellum cially the metatarsals, are very long. It has been pre- with well developed cerebellar hemispheres. This sumed that the locomotion and mode of life of the construction belongs to the type of brain structure zalambdalestids was similar to that of macroscelidids, designated eumesencephalic by Kielan-Jaworowska that is quadrupedal walking, running and jumping. (1986), which is very different from that characteristic The zalambdalestids are intriguing in some of multituberculates and Triconodontidae. Kielan- respects. Despite a number of curious specializations, Jaworowska (1984b) tentatively estimated encephal- including greatly enlarged lower incisors and elon- ization quotients of 0.36 for Kennalestes gobiensir, 0.56 gated hindlimbs, zalambdalestids were given the status for Asioryctes nemegetensis and 0.70 for Zalambdalestes of Proteutheria incertae sedis (Kielan-Jaworowska etal., lecbei. She concluded that these early eutherians were 1979), with the added notion that many of the skeletal probably more dependent on smell than most Tertiary features of this group resemble (in a convergent and Recent mammals, and favored nocturnal niches in fashion) modern, saltatorial macroscelideans (ele- which olfaction and hearing played an important role. phant shrews). Others have suggested affinities with lagomorphs or rodents (McKenna, 1975), a view Comparisons rejected, however, by Kielan-Jaworowska etal. (1979). Comparison of Mongolian Mesozoic mammals with those of other regions is limited because Late Triassic Endocranial casts of Mongolian Cretaceous mammals have not been found in Mongolia, while eutherian mammals those from the Jurassic are represented only by a The endocranial casts that are partly or entirely pre- single tooth of a docodont (Tatarinov, 1994; see also served in four out of five eutherian genera discussed section on the Docodonta above). The record of above (Kielan-Jaworowska 1984b, 1986, and refer- Cretaceous Mongolian mammalian assemblages is ences therein), are the oldest known eutherian endo- more complete. The Cretaceous mammals of casts (Figure 29.28). They indicate a primitive therian Gondwana developed in isolation from those of lissencephalic brain with very large olfactory bulbs Holarctica, and do not invite a close comparison (see Mammals from the Mesozoic of Mongolia

'triconodont' from southeastern Mongolia (Reshetov and Trofimov, 1980). A rich mammalian assemblage encountered at Hoovor consists of 'triconodonts', multituberculates, symmetrodonts, 'eupantotheres', aegialodontids, and eutherians. Hoovor mammals, except for the 'triconodont' Gobiconodon, and the multituberculate Eobaatar, are endemic at the generic level. Gobiconodon has been reported in the North American Cloverly Formation (Jenkins and SchaiT, 1988) and in the Early Cretaceous of Siberia (Maschenko and Lopatin, 1998) and is represented in Asia and North America by different species. Eobaatar also occurs in the Barremian of Spain, where it is represented by E. hispanicus Hahn and Hahn, 1992, based on isolated teeth. Out of eight mammal families or subfamilies represented at Hoovor, three are endemic to Mongolia. These are: the highly specialized multituberculate TRANSVERSE family Arginbaataridae and the two 'eupantotherian' families Arguimuridae and Arguitheriidae. The latter two families are poorly known, however, and based on CoLLICULvs genera represented by incomplete dentaries. It cannot be excluded that when better known, the type genera PARAFLOCCULUS of these families may be assigned to other families, known from other regions. Five mammalian families from Hoovor are known also from other regions. The 'triconodont' family Figure 29.28. KennalestesgobiensisKielan-Jaworowska 1969 Gobiconodontidae occurs in Mongolia, Siberia, North Reconstruction of the endocranial cast. (From Kielan- America, and in the Middle or Late Jurassic of north- Jaworowska, 1986.) western China (Chow and Rich, 1984). The 'plagiaulacoid' family Eobaataridae contains, in addition to two Mongolian genera, Eobaatar (known from Mongolia Bonaparte and Kielan-Jaworowska, 1987; Bonaparte, and Spain, see Hahn and Hahn, 1992), and the tenta- 1990; and Sigogneau-Russell, 1991a, b, 1995; Rich et tively assigned Monobaatar, also Loxaulax from the al., 1997; Kielan Jaworowska etal., 1998 and Flynn etal., Valanginian (Wealden) of Great Britain. The symmet- 1999 for reviews and references). Thus, we compare rodont family Amphidontidae comprises Amphidon Mongolian Cretaceous mammal assemblages with from the latest Jurassic Morrison Formation of North those from other areas of the Holarctica. As the America, Gobiodon from Mongolia, Mancburodon from Cretaceous mammals of Europe are hardly known, the ?Early Cretaceous of China (Yabe and Shikama, comparisons are largely confined to North American 1938) and Nakunodon from the Early Jurassic Kota and southwestern Asian taxa. Formation of India (Yadagiri, 1985). The aegialodon- The Early Cretaceous Mongolian mammals are tian family Aegialodontidae comprises the Mongolian known only from Aptian or Albian Hoovor beds, at Kielantberium and Aegialodon from the Valanginian of Hoovor, in the Gobi Desert and a single specimen of a Great Britain. To the eutherian family Otlestidae, in addition to the hlongolian ti~rmPi-ok~~iii/irIi:iti:r, belonss I~utthe so called deltatheroidan skull from Guriliin also 0tir:rrt:rtiorn the earl! C:enom;lnian of LzbeListan. .l'sn\ and the multituI>erculate Brrpiirbirirrirr fiom 'l'hc mammalian thuna from the .-\iltlers Formation Riigiin Tsa\- rrpion \\err found in beds ~)ossihl\equi\ - (.-\ll)i:in) of 'l'exas is kno\vn allnost esclusi~.el\.tiom alent to the Semept Formation. isolated teeth, \vhich do not in\ ire a close conlparison In Sortli .-\merica the Late C:retaceous (cspcciall!. with Hiiii\ iir mammals (see Butler, 10-S, and refer- C:ampanian-.\l~iastrichtian) mammal Liunas are rich ences therein). hlu1titut)erculates from the Lime for- and di\.ersitied (see I_iIlegra\.cn i~irl.,1070, and Citklli, mation, althouph ti>und half 3 centur! rigo, ha\? not 1000, for re\ien-s and references). \\-hile Late heen described, except for an abstract i hrause t.r i71.. Cretaceous mammals from \lonpolia are represented 1000). \lultitut)ercul;lte.\ from the late .\lhian Cedar b\- multituherculates, eutheri;~ns,deltatheroiclans, and hlountain I-ormation of Utah are represented h! ende~nic asiadelphians, in North .-\merica, theae se\eraI species of I'irtn~.rt~ii,.voiig.rancl these teeth are ot 2ro~1psCO-occur \vith 'triconodonts' and symrnetro- uncertain afinit!.. Laton and Nelson (1001J assipned dont~(l:os, 1000, 10-6, 1')SS). 'l'hus ir~North .\merica Pi~~i~cr~ti~:uot~~y.ito ?I'tilodontoidea and concluded (p. 'triconodonts' and s\ ~nmetreclontssur\-ived until the 11): 'Cornparison of the material from .\si;i and Utah Can~panian. pro1 ided no e\.itlencc of mu ltituberculatc eschiinge Ilurinp the Late Cretaceo~~s,the North .imerican hetaeer~.-\si;l and North .-\lnerica durinp the late n~ultitut)erculiiterissen~hlagcs were dominated b!, the Earl!, Cretaceous'. Ptilodontoidea, the *l';1eniolabidoidt.11 making their hlarnmals from the earl!. part of the Late appearance onl! at the \cry end of the Cretaceo~~s Cretaceous have not lxen recorded in .\lonpoli:l. period (durinp the hlaasrrichtian). By contrast, repre- AI~lmmalianassemb1;lpes tiom this inter\-;ll are rrire sentati\es of I'tilodontoidea have not 1)et.n ti~i~ndin and generally poorly knoan, although in the past tn.o .-\hi2 (hielan-Janoro\vsLa, 1080). LntiI recently, decades new disco\eries ha\-c lxen made in North h1onpoli:in [*ate Cretaceous rnulrituberculatcs were .\~nerica ;lr~cl .-\si;i. North .\merican ~nammrllstiom assigned to the Taeniolabidoidea. Kecent analyaes Ltah were described h!. Cifelli and Laton (I')S;), (Roupier c,r ill., IW;; Kielan-Jan-orowska and Hurum, Eaton and Cifclli (1988),Cifelli 11000, and retGrenct.5 I[)()-) demonstrated, however, that 311 the Campanian therein) and Eaton (1005). JIongoli~lnmultitul)erculsres belong to a separate Nesol pul>lished a series of papers \vith descrip- monoph!.letic cladc, for lvhich Kielan-Jalvoro\vska tions of mammalian asscmt)la~esfrom the \.ast tcrri- ~indHurum (1007) erected the suborder Djadochta- tory of aoutha-cstern .\sia (UzbeListan, Kazakhst;~n theria, regarded by LIT as ;In infraorder within the sub- and Tadzhikistan, traditiontlll!- referred to in the orclcr Cimolodonta. l'hus the Campanian Sol iet literature tls 'hliddle .\sial). 'l'he Cretaceous ruultituberculate asserublage of klongolis is very t~eds encountered there r:inpe possibly tiom ditferent from th:it of North .-\merica at higher taxo- Berriasian to hlaastrichtian, Out m;irnmals are Lnon-n nomic le\els. The only Late C:retaceous hlonpolian only from Late .\Il>i311 to the Campanian (curnmarizecl rn~iltitut)erculate tason not assigned to b!. Nesov, 108.5; Yesol rlncl Kielan-Jan-oroa sk;i, 1 ')V 1 ; Djadochtatheria is Bl/yilrbililwl; lvhich is tentati\.ely Kcso\. dill., 1094; personal conlmunication from .-\.0. attributed to the 'Cimolom!-idae. .l'his tason occurs in ~iver'yanov,see also Chapter 30). beds possihl!- crlui\.alent to the Ne~negtFormation Late Cretaceous rnan~mal nssernbl;lges of and of ?earl\ h1;lahtrichtian age. 'The presence of rare Holarctica are much t~etter knon.n. In hlongolia putrlti~e djadochtatherians in North .-\merica is nunlerous Late Cretaceous mammals occur in the do~it)tti~l. 1)jadokhta and Raruungo!.ot Vormations, nhich ;ire of The composition of the Lare Cretaceous North .?earl!. and :late Carnpanian age. In the \nunper .-\merican and hlongolian therian assemblages is also Nelnept Formation mammals 1x11-c not been found, distinctl! ditferent. \Yhilc marsupials prevail in North climates. The Upper Cretaceous deposits of south- whole. LIoreo\.er, the general debate on the phyloge- western Asia (especially the best known Coniacian netic position of ~nultimberculatesamong ~nammalsis Rissekty Formation) were deposited, as arcwed by also largely based on the anatomical data provided by Nesov, on low coastal plains in semi-humid subtropi- the Late Cretaceous llongolian multituberculates. cal conditions and the same environment n-as charac- 'The eutherian Late Cretaceous Mongolian teristic for most Cpper Cretaceous formations of mammals, although currently represented by only five North America (.\rchibald 199hb). In the Late taxa, also provide important data on the skull, brain Cretaceous vertebrate assemblages from southwestern structure, and the postcranial skeleton of early Asia and the western part of North ;\merica there eutherians. The Cretaceous marks the juxtaposition of were (in addition to mammals), sharks, ban!- fishes, several archaic XIesozoic lineages with the emergence amphibians, turtles, and crocodilians, all of which are of clades related to extant ~nammals.In many cases the much less common or absent in llongolian sites. taxa from llongolia provide the only evidence, As stated above, multituberculates were ver!. beyond teeth, for these critical branches. There are, common during the Late Cretaceous of AIongolia and however, many ambiguities remaining with respect to western North America (although represented on phylogenetic patterns. It is hoped that newly discov- both continents by ditferent suborders), while they ered material of Late Cretaceous Mongolian were very rare in south\\-estern Asia (Kielan- mam~nals,as well as ongoing anatomical and phyloge- Jaworowska and Nesov, 1992). Nesov et 01. (1998) netic analysis will impro1.e this picture. hypothesized that the 'zhelestids' and m~~ltitubercu- lates were ecological competitors. According to these authors the lack of multituberculates in Cpper References Cretaceous deposits of southwestern Asia may be explained hy the diversification of the 'zhelestids' (the .Inonyn~ous. 198 3. [P~l~c~uiitulugicaiI~istirure uf the 1, SSK first eutherians adapted to herbivorous niches) which Icad(,~i!jqf' Sciei~ces].L'neshtorgizdat, Izdatel'stvo No. 3496.35 pp. ecologically replaced the multituberculates. Nesov ct .-lrchihald,J.D. 1082. .I stud~.of 1Iarnmalia and geology al. (1098) also arbrued that the 'zhelestids' flourished in across the Cretaceous-Tertiary boundary in Garfield western Asia during the Coniacian, preceding by some County, 1Ionrana. 11zl;~er~.z(yqf Caljfi)r~ii~Pt~biicatiun~ 20 million years the first appearance of the archaic ill Geuiugicili Scie~icr~s1 2 2: 1-2 86. ungulates in North .\merica. -1996a. Fossil el idence for a Late Cretaceous origin of ,\lthough the Late Cretaceous .\sian mammal 'hoofed' marnrnals. Scic.~icr272: 11 50-1 1-53. assemblages are less diversified than those from the -1 996b. Di~io.ri~ui.E.uti~ictiu~i and thr. End qf- an ha: what tbr western North .\lnerica and southwestern Asia, they Fo.r.rils SUJ. Nen York: Colurnbia University Press, are of great value because of their unparalleled pres- SF-+23; pp. ervation. While most Xlesozoic mammal sites in the .I\er'yano\-,.I.O. 1997. New Late Cretaceous mammals of world vield isolated teeth. dentaries and maxillae with southern Kazakhstan. .Jctir Palaeontologica Polonica 42: teeth, complete skulls with postcranial skeletons are 243-256. -and Kielan-Jalvorowska, Z. 1999. h1arsupials from the only very rarely found. By contrast, XIongolian Late Late Cretaceous of Uzbekistan. tlcta Palrlrontologica Cretaceous mammals are represented, as a rule, by Poiu~iicti44: i 1-8 1. entire skulls, often associated with postcranial skele- -and Sesol: L..I. 199.5. .I nen. Cretacous mammal from tons. the Campanian of Kazakhstan. .\ieue.~. ~al~rbucl~fur Most of the Late Cretaceous multituberculates Groiogir wzd Pnlio~ztologir,.Ifo~iatsl~rjie 1995: 65-74. belong to a diferent infraorder than those from other ~~kk~~,R,T, 1992, z0fiabaararidae, a new family areas, but they provided very important anatomical tuberculate mammals from the Breakfast Bench fauna information on the multituberculate structure as a at Como Bluff. Hu~tt~ria2: 24. XIanirnals from the Xlesozoic of Xlongolia

13elyaeva, El., Trofirnor, R..I, and Reshetor, 1-J. 1974. Clernens, \\-..l. and Kielan-Jaaorowska, 7,. 1979. [General stages in evolution of late hlesozoic and \l~~ltituherculata,pp. 99-119 in I>illepraven, J..I., earlv Tertiary rnarnnialian faunas in Central .Asia.] pp. Kielan-Jarvorotvska, Z. and Clemens, '+..I. (eds.), 1 9-15. 'I i.1td7 .Sortttl:.stnoi .Soretsko-.llotrgoi>koi .Itesuzoic .Itatt1117itii..7%~ First Tzo- Thivds of' Il~ttirtiai~~t~ P~i1:~orrtoiogicheskoiEkspedLtsii 1: 1')-45. Hiitoty. Berkeley Lniversit!- of California Press. Bonaparte, J.F. 1990. Nerv Late Cretaceous mammals from Dashzereg, D. 1975. Setv primitive therian from the Early the Los .Ilamitos Formation, Sorthern Pataponia. Cretaceous of Xlongolia. Sntuvr 256: 402-403. Sntiot~alGr.opvltphic Rl:.search 6:63-03. -1V7'). .4,~rtitriuskl~oshzjari sen. n., sp. n. (Perainuridae, -and Kielan;Talvororvska, Z. 198;. Late Cretaceous dino- Eupantotheria) from the Lower Cretaceous of saur and inamma1 faunas of Laurasia and Gondtr-ana, 1Ionpolia. .icta P~i~trutrtulugicnPoiotricir 24: 199-204. pp. 2+29 in Currie, P.J. and Koster, E.H. (eds.),lultt.th -1991. Trvo prer.ioasly unknown eupantotheres Jynrpo~.iut~on .Ite.iuzuic Ti~rve.itviai P;cosystems. .Shot-t [hIammalia, Eupantotheria). :litie~icitt~ .Itu.rrutrz Plzpevs. Occnsiurl~zi Plzpevs of the Zjvveii .If use~ttti 01- .\'oi'itntes 3107: 1-1 l Pitlaeu~itulogy,Drnnlhrllrr 3 -and Kielan-janororvska, %. 1984. The lower jaw of an Butler, P.%I. 1978. .I new interpretation of the mammalian aepialodontid mammal from the Early Cretaceous of teeth of trihosphenic pattern frorn the .Ilhian of hIongolia. Zouioxicai .yout-trai o/- the I.rti11t~iz17Societj 8 2: Texas. Bvmiuvir 446: 1-2 7. -71--77j -- . -1988. Docodont rnolars as trihosphenic analosmes -, Sovacek, \I,J., Sorell, Xt..I., Clark, J.XI., Chiappe, (htamrnalia, Jurassic), pp. 329-340 in Russell, D.E., 1-.hI., Davidson, .I., XIcKenna, XI.C., Dingxis, L., Santoro, J.P. and Sigogneau-Russell, 1). (eds.), Ti~i~th Srvisher, C. and ;\Itanperel, P. 1995. Extraordinary Kez~irzted Procr.edit~g o/- the 1711th Iirtrvnntiotral preserlation in a new lertehrate assemblage from the S'nzposiutn otr Di~ntiti.Ilovphology. .Ifiitioivs dir .Iluic~~rtti Late Cretaceous of Xlongolia. .\-ittuvi~374: 446-449. LVittiuizitld'lIi.itoivi~ .\ittuvelllc; Pirri.i. 5 3. Eaton J.G. 1995. Cenornanian and Turonian (early Late -1')')O. Early trends in the evolution of tribosphenic Cretaceous) n~ultituherc~~late~na~nmals from south- rnolars. Rioiugical Keviras65: 529-552. western Ctah. .'fotttval of let-ti~brirte I'aleo~itology 15: -and Kielan-Jarvororr-ska, Z. 1973. Is Deltirtheridiirtt! a mar- 761-784, supial? .Yitture 245: 105-106. -and Cifelli, R.L. 1988. Preliminary report on Idate Carroll, R.L. 1988. 1 >vt~,bvntepni~~o~ttuio~itnd ei'oi~~t~oti. Sen Cretaceous marnnlals of the Kaiparowits Plateau, York: W.H.Freeman and Company. xiv+6')8pp. southern Ltah. Co~rtt~ibutio~isto Geoio~l,Lliii'ersi~)~ of Chorv, h'l. and Rich, C. 1984. .I new triconodontan 1L jo111itrg26:45-i5. (h'lammalia) from the Jurassic of China. .7ourn~luf -and Selson, X1.E. 1991. XIultituberculate ~nainmals livt~brat~Paleotttoiug) 3 : 22 6-2 3 1. froin the Lover Cretaceous Cedar 3lountain Cifelli, R.L. 1990. Cretaceous rnamrnals of southern Ctah. Formation, San Rafael Swell, Utah. Culztributiotis to I\.: Eutherian mammals from the \Vahn.eap (.Iquilan) Geoiog: C11ivet-si[yof Ir,Zot~zilzg29: 1-1 2. and Kaiparowits (Judithian) formations. .youvtlnl uf Engelmann, G.F. and Callison, G. 1999. Glirodon grandi.r, a It~rtebvatePnieotitology 10: 343-360. nen- multituherculate mamrnmal from the Upper -19V3. Early Cretaceous mammal from North .Irnerica Jurassic Xlorrison Formation. In Gillette, D.D. (ed.), and the evolution of marsupial dental characters. 1e1,tebmte Paieontoiog) ifz Llah. Ctah Geoiogicai Sut-dry Prucecdinps of the .Yiztioitni .,fcnde?n)~uf Scieiice~:L.S.4 90: Pltbiicntio~r99-1: 161-1 i8. 941 3-9416. Flynn, J.J., Parrish, J.Xl., Rakotosamimanana, B., Simpson, 1WO.Trihosphcnic mammal from the Sorth .Imerican 1f:F. and 'Ayss, A.R. 1999. A middle Jurassic mammal Early Cretaceous. ~Yatuve401.363-366. frorn hladagascar. .\ntuve401: 57-60, -and Eaton, J.G. 1987. 3larsupial from the earliest Late Fox, R.C. 1969. Studies of Late Cretaceous vertebrates. 111. Cretaceous of \Vestern CS. .\irttrre325: 520-522. .I triconodont mammal frorn .Ilberta. Cn~indian -and Muizon, C. de 1097. Dentition and jaw of Kupeiiict .?";7211,tznio/ Zooiog) 47: 1253-1 256. juddr, a primitive n~arsupialor near-marsupial from -1974. Deitathevoidi~.r-like niamnials from the Upper the kledial Cretaceous of Utah.,7ouviraiof .Ifatn~!aiinti Cretaceous of Sorth .Imerica. .\irtui,i~249: 392. Fuoiutio~c4: 241 -258. -1976. .Idditions to the mammalian local fauna from the Upper JlilL Ri\-er Formation (Lpper Creraceousi, 1993. The s!~tematic arrangement ot [lie Paul- .\lberta. Cie~i~cdrnii;?o~/i-riic/ o/- I;iirtb .Si.i!~iic~~c1 3. choffiiriidac (Jlultituherculata) re\ isited. (;~O/OFI~Nc/ 1 105-1 1 18. Pi~/i/t~ollro/o~~e~iz2 7:20 1-2 14. 1078.Upper (:retaceous terrestri:il 1-errebratc stratigra- -and Hahn, R. 1983. llir/rir~cht~ri.~e/i~ri~,in \\cstphal, F. (cd.), phy of the (-;oh Desert (\[on~ol~,inPeople's ~'ll~~~l/~l~liiCi~rirl~~~,., I 1i11111irlri1, Pars 1 2 7, .11nsterd:i~n, Republic) and wesrcrn Sorth .\rnerica, pp. i---i94 in Lupler Publications. 4OV pp Stelck, C.R. and Charterton, D.E. (eds.). li>~./tsriririid and1002. Seue \luItituherculaten-Zihne aus der 11,crii. C~irirdiiri~Bio.itiirti~~-irp~j. (;L'O/OSI CN/ I.I~.~o(.IN~~oIIq/ Unter-Kreide (Barrelnium) \-on Spain (Gal1.e und C~~I~(IL/II,.S)rc~~~/pi~prr I 8. Lti a ). G~~i/ogic.~carPir/i~c~uiiro/o~ii.~ 2 6: 143- 1 62. -1080. Pii.op.riipir//c~:ro~ir,n. pen. and sp., an unusual therian -and I'J'JO, Pinhcirodonridae n,faln. (rn~~ltituherc~~lata) from the Upper Cretaceous of .1lherra, and the (m~i~nmaliajaus dcr ricfcn Unter-Lreide I'ortugals. classihcation of primitil-e tribosphenic lnammals. I'irlirt~oiito~i-irpbrci~,lb/ri/rri~g, I, 2 5 3: 1- 146. C~7l~d~iltl~~~ll)*ll~/0/~E~rrh.S~it'll(.ei- 17: 1489-1 498. Lepqe, 1.C. and \\.outers, G. 198;. Ein hlulti- -1985. Upper molar structure in the Late Cretaceous tubercularcn-Znhn aus der Oher-'l'rias \.on Gaume s)-mmetrodont Sy~iiiert~ti-u~/uirroidt~sFox, and a ( S-B el pien i. Urr//cril~dt, 117 Suciirt; Br~Igcdca (;6olugi~,96: c~.ciss~hcation. . - of the S!.m~nerrodonta (\lalnrnalia). -3 9-4 -. j'olri-ilir/ (I/-P(~/c~or~ro/o.~ 59: 2 1 -1 6. Ilopson,!..1. 1004. S!.napsid e\.olution and the radiation of 1900.The rnonoph! I!, of the l'aeniolabidoidea (mam- non-therian malnmals, pp. 190-1 19 In Prothcro, D.R. malia: \lultit~~herculata),p. 26. III Lcan~ii,fl..1. led.) and Schoch, R.11. (eds.), IfilJor Fii~rtr~~c.ru/- I>rrr~hi-wrc, I-II ~ll~l'il1ll~i0ll~/~~II~~OS~I~III 011 1 lt.1.0301(. Tf'l.l?..l TI,;N/ L';~O/I~~IOII..Shorr (:or/r~.<>.i 111 I'~r/~~ej~~/o/cigy 7: 190-2 19.

F:co.c:j.src~i~z.i:. 16.itnrct.r. Buenos .1ires, 64 p p. -1 9V5. TheJurassic mammal Sbuorhci-irrlel dufrgi: 'pseudo- Freeman, E.F 1979. .\ Jliddle Jurassic mammal bed from rrihosphenic therian', docodontid or neither? :~U~OU~IIN~ Oxfordshire. Pci/crc~ui~rolo~j22: 1 35-1 66. q/' I t~rrt~bi-i~rt~Pi~/~~o~r~/o~)15, Supplement to No. 3: 36.1.

Gambaryan, P.P. and Kielan-Ja\\-oro\\-ska, L. l00.i. - Lielan-Ja\loro\lska, Z, and .illin, E.F. 1919. The cryptic Jlasticatory muscolature of .1sian taeniolahidoid ]up of moltit~iberc~ilates..Tot~i-il~/ u/ birrrb~-art, ~nultituberculare mammals. .icrir Pir/erc~or~ru/o~~c.(~ PN/~,U~I~U/UJJ9:20 1-209. Po/ur~ii.ir40: 45-1 08. Hu, I-.,11-anp, I., Luo, Z. 6 Li, Ch. 1907. .I nen symlnetro- -and- 1997. Spra~vling ~t,i-susparasagittal stance in donr mammal from China and its implication for rnultituherc~~late mammals. 1crc1 Pi~/i~c.ui~rulo~ici~ mammalian el olution. .\;rt1/rr390: 127-142. Po/ui1ii.c142:1 3-44. Hururn, J.H. 1004. The snout and orhit of Ylongolian Gingerich, P.D. 1077. Patterns of el olurion in the mam- n~ultitubercalates studied b!, serial sections. .1cri1 malian fossil record, pp. 460-500 in Hallarn, -1.(ed.), Pir/irror~ro/o~~i.nPu/oi~ic.tr 3 9: 18 1-1 11. P~rrer71.1-or Ei.u/utiui~..1msterdam: Else\-ier Scientihc -1998a. The braincase of tuo Late Cretaceous .1sian Publishing Cornpan)-. mulriruherculates studied by serial sections.

pp. 7C90 in Lillegral en, J..i., Kielan-Jan-oron-aka, L. K~elan-Ja\\oro\\ska,Z. 1060a. I'relimlnary data on the and Clemens, \F-..I. (eds.), .11~~so;oic.~~UIIIIIIN~.C. Tht'Fri5t LTpper Cretaceous eutherian mammals fi-on) Rayan I-'ir. of fn11111~z1ia1iHirtury. Berhele!; Dzah, Gobi Ilesert. P~lirt~ortrulu~rirIJu1orirc~r 19: l i 1-1 9 1. University of California I'ress. -1Y69b. Ilisco~er! of a multitubercnlare ~narsupialhone. Cronipton, .i.Q. and Downs, R:R. lY8.3. \lesozoic .\iltrrl9~222: IUOI-lOY2. mamnials fronl .-lrizona: ne\\ e\ idence on ma~nmalian 10-0.Sew Cpper Cretaceous multitubercnlate genera evolution. Scirrcre222: 1233-1 235. froin Ba\an Dzak, Gobi Desert. Pitli~ro~ttologiul'olo~iicir andSchaE, C.R. 1988. Ihe Early Crataceous mammal 21. .:i-49. G'obicorrodorr (hlarnrnalia, Triconodonta~ from the -19-1 Skull structure and afiniries of the Cloverly Formation in llontana. .forrnrirlo/~ lirtrknrtt. 111 ~tituberculata.Pi~ltllitroi~tolo~ii~ Polortrrir 25: 541. l'aleo~ttolog~~6:1 -2 4. -lY-4. Ilultituherculatc succession in the Larc Jepsen, G.L. 1940. Paleocene faunas of the Polecat Bench Cretaceous of the Gobi Desert (llongolia). Formation, Park Count!; \Vyoming. Piwt~t~t~ilrrrgsof thr Pi~li~roritolo~ii~IJu1oiiii.ic 3 0:2 i-44. Imevlctrrt Phrlosophici~lSoc~r~y 83: 2 1 7-341 -10-5,. Evolution of the therian mammals in the Late Jerzykiewicz, -I:, Currie. P.I., Eberth, D..i., Johnston, P..i., Cretaceous of .isia. I'art I. Deltatheridiidae. Koster, F:.H. and Zheng, J.-J, 1003. Djadohlita Piliirt~olltoiogrilI'oio7lrt.ir 3 3: I 03-1 32 Formation correlative strata in Chinese Inner -10-51). Preliminary descnprion of t\\o nea eutherian Xlongolia: an o\erT ien of the stratigraphy sedimen- genera from the Late Cretaceous of 1longolia. tary geolog!; and paleontology and comparisons with Pal, eorrtologia Poloriicir 33: 5-1 6. the type locality in the pre-.iltal Gob]. Cirriirdririi -19-Sc Possiblc occurrence of marsupial bones in .fi~urrtalof' Earth .St.ir~rrc.r~s30: 2 180-2 1 Y5. Cretaceous eutherian mammals. .\irttrr-~255: 608-600. -and Russell, D..i. 1001. Late \lesozoic stratigraphy and -19-7. E\olution of the therian mammals in the Lare

\ ertebrates of the Gobi Basin. Cretirceou.~Rr.icairir,l, 12: Crt taceous of .isia. Part 11. Postcranial skeleton in 345-377. ht~ririnlr~stt~sand .isiorjctt.s. Pi~li~t~o~itologii~Polorricir 37: Ji, Q, 12uo, Z. and Ji, S. 1999. ;I Chinese triconodont 65-84. mammal and mosaic e\-olurion of the mammalian 10-8. ET-olution of the therian mammals in the Late skeleton. .\'irture 398: 326-330. Cretaceous of .isia. Part Ill. Postcranial skeleton in Kemp, 7:s. 1983. The relationships of nlarnmalf. Loologit.nl Lalambdalestidae. Pirlliic~~orrtologinPolorricir 38: 5-41, j'ouvrral o/- thr. Liririeari 5ocit.t~'77: -3 5 i-384. -1979. Pel\-ic structure and nature of reproduction in Kermack, K..i. lY67. The .iegialodontidae - a ne\v family \lultitubcrculata. Sirtun.277:402-403. of C retaceous nlamni als. Proct.t~iirigs 01- thr C;r~ological 108U. .ibsence of ptilodontoidean ~nultituberculates Soc~i~yof' I.oiido~i 1640: 146. from .isia and its palaeogeographic implications. 1088. British hlesozoic mammal sites. Spcciiri Pirpt2,i. rri 1-tzthnin 13: 160-1 73. Palaeo~itolo~~40:8 5-0 3. -1981. Evolution of the therian mam~nalsin the I>are , Lee, .ill., Lees, P.hI. and hlussert, F. lY8'. .i new doco- Cretaceous of .isia. Part IT: Skull structure in donr from the Forest hlarble. %oolc~grc~~l.~ouri~i~lof' thta ht~1111~1r~stt~sand .isiorjctt~.s. Pi~lai~orrtologiirI'olorrinr 42: I,i~r~iru;iSociety 89: I -iY. 2F--8. -, Lees, P.hl. and hlussetr, E: 1065. .irgiaIodoii dir-sorrr, a -1984a. I:\.olution of the therian mammals in the Late new tuberculosectorial tooth frorri the Lon-er Cretaceous of .isia. Part \: Skull structure in healden. Pvocecding.r of' the Rojiri Socrc.9 of' Londoii, Zalambdalesridae. Pirliteo~itoiogiicPoior~rcir 46: 107-1 17. series I3 162:535-5i4. 1984b.Evolnrion of the rherian mammals in the Late -and hlussetr, F, 1958. The jan articulation of the Creraccous of .isia. Part 1.1. Endocranial casts of Docodonta and the c1assihc;lrion of \lesozoic eurherian mammals. Pirlacor~tologia Polo~iicir 46: mammals. Pvocer,dirig.i o/- the Rojizl Societj o/- Loiidort, 15--1-1. staries R 148:ZOCZ 15. 1084c. ET-olurion of the therian mammals in the Late , hlussetr, E: and Rigne!; H.\T: 197.3. The loner jan of Cretaceous of .isia. Part \'Il. Synopsis P~lirr~oritologrii .~IoY~~~~Ico~oIL.Zoological .founial or tht, L~rir~eniiSoc.it,l) Po1oriic.n 46: 1 - 3-1 83. 53: 87-17.5. (:oliti-ihictioiis lo (;t,olog). [ iir;c,,lricy of Tijoiriiiip, Sp~~iirl -and- IY')?. \Iultituberculate ruummals horn the I'i//lt~i.3: 2 I -.34. Crcraceous of Uzbchistan. :lrtii Pirlirru~rulo~icnI'ulu~zrcii -1004. .A ne\v pencric name for the mulrir~~berculare 37. 1-1 -. ~n:~~nmal'Ijiilorhnhtrii~ii ///loid.i .let# , Preslev, K. and Poplin, C. 1986. 'l'he cranial vascular I'iiliirnrirulo~ri.iiPoloi~irii 39. 1 Zt 1-36. svstem in racniolabidoid ~nulrituherculaternalnmals. -Ic)')- Chal.acrers of mulrirubercul~~tesneelccred in Philo.i.o~phiriil7 >nnsnrr~ulisuf' rhr Rojnl .Surrr,

1111 IWV .~~ftl/~i1/0 ilr, ('irvir~~ri~.\ ri~~~i,iilr,.s 'B~r~iiii~di~io ( llonsolia). .ir.m P~~lii~~oliroiugiraPoluliir~~ 14: 34.5-373. Ri:-iciIiiciii'S.S. 145: I-Y -and Trohmol, B..A. 1980. Cranial ~norphologpof the -13o\vn, T.lI. and Lillegrax-en, J..A. 1979. Eurheria, pp. Cretaceous eutherian nlarnlnal Hiir~~rlert~s.-4rrii 221-158, in Lillcyral-en, ]..A,, Kielan-la\\-orox\-ska, L. P~~IiirolirulogiraPolofzicn 2 5: 167-1 85. and Clemcnc, \\: A. (eds.), Ilt~o;u/r~II~~IIIIIIII~T. Thr,fivsr Krause, D.\\: 1981. Jan. movement, denral f~~nction,and r;x-ibri-~liuj nii~iiii~ii~liir~ihisrui:~. BcrLele!; Unil-ersir!. of diet in the Paleocene multiruberculare Pti1uilu.r. Calih~rniaPress. Pnlt~ohiolu~y8: 165-2 8 1. -(:ilelli, ILL. and Luo, Z. IYYS. .Alleged Creraceous pla- -1986. Comperiti\-e exclusion and taxono~nicdisplace- cental from tlon-n under. I.tth,iin 3 1: 16'-268. ment in [he fossil record: the case of rodents and ant1l>ushzc~e~, U. 1078. Sexy l>;lre Cretaceous mammal niultituberculares in Sorth .America. (:oi~triburioiisto locality ant1 a description of a ne\v mulriruberculate. Grolog). [ iiict~r.i.rpof 1rr)oilrrlig Spr~cinlPnprzr 3: 95-1 17. lrrii I~iiliir~o~~tuiufiriiI'uio~ric~ir 23: 1 1 F-1 -30. -and Jenkins, F.:i. Jr. 1983. The postcranial skcleron of -and lY80. Eutherian manlmals from the Early Sorth .irnerican multit~~herculates.Bu~~er;~r of /ht Cretaceous of llongolia. Zoulu~irii Scri/~ri/ 18. .11riir.u111of' Coiirprtrnrii~r~%uulo~y 150: 10')-246. ~34:-375 -kielan-Ja\roro\rska, Z. and Bonaparre, J.E: 1991. and1WS. Earl! Cretaceou5 amphilesrid i'tricon- Frni~Iiurhr~riu11iBonaparte, thc hrst known multituber- odont' mammals from \Longolia. .lrtii Pnli/r~o~i~ulo~icr/ culate from South .imerica. ~ofuu~-~inlof ltvttbmre I'uloii~r~ri43: 4 I .<-4~38 P~~lr~uliroloiy)12: 35 1-376.

--, and Trohrnov, B..A. 198-. Earl!. Cretaceous multitu- kielan-Jan-orolvska, Z. and Turnbull, W.D. 1990. Early I~erculatesfrom lIongolia and a comparison n-irh Cretaceous llultituberculara (hlammalia) from the Lace Jurassic forms. icrii P/iIiit~oiirolo~ic~~Polo~~ir~ 32: .Anrlers Fornulrion, Trinity Group, of north-central 3-47. Texas. .Torirf/u/ of- 1 i.vtthvnrt Pii~eolitulngy 10, -2nd Ensorn, 1'.C. 1YY1. llulrituberculare mammals from Supplement to no. 3: 109.1. the Upper-lurassic PurhecL Lirnestonc Formation of Krehs, B. 1991. Das Skelett von Hntkt.lorheriuln guimsvume Soi~thernEnpl:lnd. Pirlr~i~o~irulug35: 9F-120. gen. et sp. nor (Lupantotheria, 3lamrnalia) aus de~n -ant1 (.;ambar\.an, P.1'. 1994. Postcranial anarolny and Oberen Jura von Porrugal. H~vli~irrGt~uwissntsrbnftlich~~ habits of .Asian mulrirubercuI:rre mammals. Fo.iri~~.dlii/ .ihhri~idIri~igc~i..ihrriItilig.A 1 3 3: 1-1 2 1. .Sti-ii~/i3 6: I -Y 2. -1998. L)i-e.ichcv~~rhrriu,n~icruiti gen. et sp. no].., ein neuer -and Hurum,J.H I YY-. Djadochtarheria, a new suborder Eupanrotherirr (lLamrnalia) aus deln Obcren Jura

of mulriruherculare rnammalc. .1c/11 P/rIriro~t~ulo~irir \ on Portugal. BPI~~IZCI*G?omi.r~t~n~-chaft(iChP I'olo~~ir.ir42: 101-141. .-lhhn~tci(u~~gr~~,.-Il,tcrlu~igK 2 8: 9 1-1 1 1. andScsov, L.A. 1990. On the mrtarherian nature of the Krusat, G. 1969. Kin Pantotheria-hlolar rnit dreispitzigcn lleltathcroida, a sisrer group of [he llarsupinlia. Talonid aus dem Kimmeridge von Portugnl. I,t~hiii,r21: 1-10. Pnliio~trulugi~chc.Zcirschl-ifi 43: 5 2-5 6. lIammals from the AIeso~o~cof bIongol~a

Li, Ch., Wang, Y., Hu, Y. and 7,hou, 11. 1905. .\ symmerro- Szala); F.S. (eds.) Phyioge~~'qf the Prinmtrs. New York: donr skeleton from the Late Jurassic of Western Plenum Press. Liaoning, China, p. 233 in Sun, .\. and iyang, Y. (eds.), -198;. llolecular and morphological analysis of high- Sixth Sympo.rium on llesozoic 7 Prrt.striu1 Ecosystt~~nsiznd level marrimalian interrelationships, pp. 55-95 in Biotu. Short Pape~r.Beijing, China Ocean Press. Patterson, C. (ed.) llokcu1r.r and .lforphology in Lillegraven, J..\. 1969. Latest Cretaceous rriammals of otio: Cotlflict or Co~npromisr~? Cam bridge: upper part of Edmonton Formation of .\lberta, Cambridge Cniversity Press. Canada and review of marsupial-placental dichot- -and Bell, S.K. 199;. Clussifi~.utionof' .lPammnl.r .?bone the omy in mamn~alian el-olution. 7%e C-nir~ersirtebratePaleontolog)' 13: 309-334. Xlills, J.R.E. 1971. The dentition of .llorgiotucodo~c, pp. SlacPhee, R.D.E. and Noracek, hllj. 1993. Definition and 29-63 in Kermack, D.11. and Kermack, K..\. (eds.), relationships of Lipotyphla, pp. 13-31 in Szala!; F.S., ERI~J.I~~IIIIII~~S. Zoological ~our~zalof the Linnean Society Novacek, hLJ. and hlcKenna, 3L.C. (eds.), .\tuaitnul qf Londo~e50 Supplement I. pbylogny: Place~ztuls.New York: Springer-i7erlag. hluizon, de, Ch. 1994. .\ new carni~.orousmarsupial from McKenna, M.C. 1975. Toward a phylogenetic classification the Paleocene of Bolivia and the problem of rnarsu- of the ALammalia, pp. 2116 in Luckett, n:P. and pial monophyly. .Vature 3 70: 208-2 1 1. Scsot, L..l. 108.5. !Ye\\ 111a11inialsfro111 the Cretaceous of I u/~~iiit,2 Pii//l>rii~-01. h'ri-iir~ri~i.li/17111/ S'~srt~it~i~/~c Ili~~~i~.si~~~. Kvzvl k 11111. 1 1 13~~11ikI. ~~III~~~I-~II~.~~~II~II 1 ~iii~~~~~~~irt,ri/1 7: 8-1 S C:hicayo: The Cni\ ersitl of Chicap Press. -1')OO. /Small iclitli\~ornitliif(>r~iibird a~idother bird -lorell, \I., 1lcKenni1, \I.C. and Clark, J. 1004. Fossils of remains from the KisseLt\- Formation ~Lpper tlie Fla~n~ngClifs. .jrit~iiiific.li~ic.i~rciz~iDecember, 1994: Cretaceol~s)of Central hv7\.lL~1mIlcsert,. 'Ij-iii()' 60-61). %uoIu~ichc:cko~~i111.iririiiii I.\-SSSK 2 1: iY-62. Rouyier, C;.\\., \\'ihle,J.R., \IcKenn;l, \I.C., Daalize\.eg, -1 yc)-. 1 (,'~r'~~lCt'ull,i oil- 1~ilriilc~ 1 t~r~t~/ll'ii/l'~.01- .\ ~ji.rht,rii I1, and Horol- it^, I. 140-. ILpipl~hicbones in eutherian J,iirii.~iii.](Ld~ted I)\. GoI(l\ ~ie\:I, L.B. ~1r1c1.I\ er'~ :111o\. rnan~rl~alsfron~ the Late Cretaceous of Alon3olia. .l.0., St. Petcrst~urp:Institute of the Earths Crubt, St. .\iiriri?, 389: 483-486. I'etersburg Cni\ ersiti-, I l b pp. P~sc~~ill,R, Goin, FJ., Icrause, I).\\., Oritz-Jaure~ui~ar,E.

- .lrcliihald, J 11, and hiel;i~i-!a\voro\\sL;l, Z. IY')S. and Carlini, .l..l.I')OO. 7'he tirst gnath~cremains of Cngulate-like n~ammalsfrom the Lare (:reraceous of' budanlerica: Ilnplicarions for gond\rantliere relation- U~bckistiln ~ind a phvlogcnet~c ;~nal!-\is of ships. .%iiii-iiiilof 1 i,~-ic~hriitt,P~r/t~o~rrolo~g 19: 3 7 3-3 82. Cnpulatomorphi~,pp. 40-8S in Bci~rd,C:, and II;i\\-son. Prothero, U, lYS1. lei\- Jurassic mammals from Como

\I. (etls.), 'I%tz Dii ~iio/' rht, l~.;ilii I101iiiiiiil.i. ljiiiit~iiiof Blu~:\\voniing, ant1 the intt.1-relationships of non-tri-

tht, (,'iir~it:~it,I I /is-taiiiii .Yii~iii~liIHj.itoi;)'. bosplicnic .l'hcria. Hirllt,rili of rhea inii.~-ir,rtl~.Ilu.~.rui~z o/ and Kielan-J;l\voro\\sLa, Z. lC)C)1. El-olutioli of the \;itiiiu/ Hirtoi~1 67: 280-32 F. Cretaceous .li~antherian mammals, pp, 5l-i7 in liiduleicu, C, and Samson, P.-\I. 1096. The tirst multiro- Kieliln-Ja\vorc,n-sLa. %., Heinrz, X. id SaLrem, H..l. I~erculate skull from [lie Late Cretaceous ( eds. ), F//?/I h'~iiipos-iiiiii 011 1lc.1.11z11icT13i-rt,.-ri-iii/ F~ro~:)',~-tciii.i i\l~lastriclitian) of Europe (Ha~e?Basin, Romania).

II~I~~~(ITII. I~..vr~i~~lcd .lh.~/r(ic.r.i. (2'~~~ir~~ih~~ri~~~~~~/?0ii1 rllt, .I~I~III~III Ii~.rr~r~~tiiIi~~ (;t~olo~ic[IIROIII(III;~~ 96, S~~p~>le~iie~it P,ilizt~o~/rolc~~~r.ni.I lirst~i~ii~, 1 iii;.t,i:t I!) of O.i/o 364. I [.lI)str;lcts): I -:-I 7s.

- Sigogneau-liussel I, D. and Iiussell, D.1,:. 1904. -1 sur\ eT- lieshero\, \:\. and l'rotimo\-, R..l. IYHO. [The main stages in of Creraceons rrihoiphenic ll~ar~~rnillbfrom \licidle rhc de\-elopnienr of .hian ~nar~llnals,]pp. 1 I +12 1 in .lsia (Uzbekisran, KazaLlisran and .l'aiiLisrani, of [heir SokoIo\-, 13.5. (ed.), Pi~/iic~ortrulog): .Sr~~~~ri~ri~p~y. pcolo~ical settilip, age ant1 faunal enr-ironment. Inrernational Cieological (:ongress, 76 session. l'i~Iir~oi't~i~r~~/~ri~i~i2 3. 5 I -9 2. \losk\ a, X;lu ha. -and l'rotimo\-, R..l. I')-O. :.lncicnr insecrii ores from [he Rich, T.H., \-icLers-Rich, P, Consrantine, .I., I:lanncrr, Cretaceous of Lzbek SSK.! Dokliiil) .i.\ SSSK 247: -l..l., Kool, I-., and on Iila\.eren, S. 14'47. .\ rribos-

C)iirii .\~~~~qr~iii~z.Vnpublished Ph.D. Plenum Press. ,Ihesis, . Uni~-ersidad Sacional de Buenos .lires, -Ic)86a. l'he prinliri\ c elltheria11 denral formula .7oiii-ii~i/ Facultad de Cicnc~asExacras v Saturales. Buenos q/. 1 t~t*~c61-[1/t~/'[l~coii/(I~u~)' 6: I 0 1-1 Y 0. lires. -20 pp. 1086h. The sLull of lepticrid insecrii-orans 2nd tlie -, So\acek,\I,]. and Dashzc~-ep,11. 1997. .l new multitu- higher-lei el classification of eurherian mariimills. hcrculare from [lie Late Creraceous locality Ukhaa Hi~iit.ri~i(I/- rht,. IIIII~~~;.IIIII IIIJ.~.III~I of- .\;iii117ii Hi:sior) 183: Tol~od,\lonyolia. Considerations on nlultirubercu- 1-1 I I. larc inrerrelationships. .liiic'ric~~~~IU.Z~VIIII .\hn~tate~ -1000. lo^-pholog!-, paleonrolop!; and thc hipher cli~des 3191: 1-26. of ma~nmals.('iiri?.iii lliiiiiii~ii/~~~)-.7. >Ob-.i43.- -. \\'ible, J.K. and I lopson, J..\. 1092. Kcconsrrucrion of

-1002. llammalian phyloscnv: shaking [lie tree. .\/iiiiiz, the cranial \ cssels in [he Earlr Cretaceous lnammal 356: 121-I?.<. 1 iiicc~l~~.irt~s~it~iiqrrt~ii~i~~i~i~: iniplicarions for rl~eevolution -1903. Patrerns of tli\ersitr in [he mam~naliansLull, pp. of mammalian cranial svsrem. j'ouriiirl qf lirtr~brart, 438-i4.i in HanLen,J and Hall, R.K. reds.), 'l%t~Skii// P(i/c~orrruiug)'12: 188-2 16. \lamma1 from the \lesozoic of \longolia

, \lit~le,J.R.and Hopson,J..\. 1006a. Basicranial anacorn1 and Godetroir, 1'. 100-. .I primici~e docodonr and relario~lships of Pi-incoiiuii ~~~III~I~I~II.~~~.~(\~21lllll;lli~~ fro111 [lie Lpper 'l'riassic of France 2nd (Triconodonr~dae,\larnmillial from che [.aceJurassic che possible cherian aftin~ciesof [he order. Cni~ip/i,.s of Colorado . 11ii~~i.ici111.lIir.i.t,i~i~i .\/~;~i~ii~c~.i 3 183: I-:S. Kcziii/i~.ii/c, 1: lriidt:i/iit>i1c.i- S(.il~i/~l,.i,l'ili.is 3 24: 1 3 5-1 40. -, 11-ihle,J.R. ancl So\aceh, \I:I, 149611. \lidcllc-car ossi- S~~nmon,N.U. 1003. Ph1-loyen!. of \lulcicul~erculaca, pp.

cles of che nlulcirul~crculacc hi:yprohiiiir~/r from 146164, ill Szala!, F.S., So~acek,I[:]. and \Icl.;cnnu, \longolian Lace Cretaceous: implic;lcions for 1113111- .\ I .C. ( eds. I, I lii~~iiiiii/Pb)/oxc~r~~: I 11:i.o;ort. I~lff;~fi~~irii~rrc,,i, nlaliarnorph relacionships 2nd el olurion of [he audi- .I Ii~/riri~ht~r~!i/i~tc.i,I IOI/~~I~I~/II~~.I. Eiii-1)' Thl~i,/i/~/.i117id .I Iiirsii-

[or!, apparlirus. I~~it~ric.i~ii.Ilirsc~!iiii .\>;.i~ir/c:i 3 187: 1-4.:. piiil): Sen lurk: Springer 1.erlag. , \Vihlc, J.K. and No~acek,\I1]. IOOS. Inlplic~irionsof Simpson, G.C; 192ia. .I \lesozoic mammal shull From

L)t~/rtrrht~i-iiIi~,inspecimens for earl! ~narsupialhisror! \lo~l~oli;i.. lii~t~ri(~i~i~ .lJii.~-ci~ii! .\~o;i/i~t~,.i 201: 1-1 I.

.\nriii-c 396: tic)-463. 14lib.Ilesozoic \lanimalia [[I: Prelimintlr!. conlpari- Kone, -1.. 148S. Dehnicion, d~agnos~s,ancl ori~inof son of Jurassic ~llanlnlalsescepr mulcicuherculaccs.

Alammalia. .fi~iii-iiitl or 1 (~i.r(~hi-~~rtI'ii/t~uii/o/o~j 8: .JIIII~~~(~~III.~o~II~II~~/ qf ,Sc~t,iil.t, 10: iic)-i 6c). 24 1-204. 102-. \[esozoic \lani~nalia,I\;: The hrain of Jurassic -Iv9!. Ph)-loycnecic sj-sce~n~itioand rhe earl! 111sror!- of 11ia11111i;lls..IIIII~I~~~~~I/ .~OIII-II~I/ u/' Sl~i~c.~~14: 7.50-268. manlnlals, pp. 174-145. in Szala!; l,..S., So\aceh, 1\11, -1 97 8. . 1 ~'ii~ii/o~!~e,uf' 1/11> I le~.rnz.ui~~.I I~IIIIIII~I/III T/I~

and \lcl.;enl~a, \I.(;. (eds,i,.lliiii~ii~ii/P~)/o~t~i~) .Ilt,.io:oic. (;:~ij/o~i~ii/L)t,/)irrt~i~cwt (!/' 1151, Br1tY.1-h .I~LI.~~,I/III.12~~ricio~i: 111/1 1 ll/i~htlii/llts, 1 lll/lli:lll~.i, I;NI-/) Brirish Iluscu~n(S~icl~ral Hiscor!.), 21.7 pp.

T~~,I,I{III.I;i111i/.1 Ii~i:iir/~ii~/s. Se~v lork: Spri~iyer-1crlap. -Ic)/4. Imcrican .\lesozoic .\larnlnalia. Illa~~ioil-sn[ rhr,

Sereno, P. and Ilckenna, 1I.C. Iclvi. (;~CC~CCOUS111111cic~- /'~,i~hoi()'I~/I.~I~//III nf. 1 [//I> 1 II~WI:I ;I) 3: 1-7 35. L~crculare skeleron and the early e~olurionof the 193-. Skull scrucrure of the Ilultituberculara. Bii//~~iii

man11n;llian shoulder ~irdlc..\nriii-t.3 77. 1 ++Id-. of T/IC . 1111t,ril.i171I II!.~~~~!IIIqf .\-iir~rril/ //I.I.TuI:~~73: Secoyuchi, T., Tsuba~noco,'I7., Hanamura, 13. and Hachi1 a, -2---6.3. K. 14Yc). .In early Lace Cretaceous rliainmal fro111 Sloan, K.E. 19-4. Ilulcicut~erculaca, pp. 402-408 in Japan, u.ich reconsideration of the elolucion of tri- Fairhridpe, R.111 and Jat~lonshi, I). (eds.), Thta bosp[ienic molars. I)i~/t~uiiro/o~icN/K~~s~~iii~ch3: I h-28. /.lii~~r./o/~c~i/iiiof' /'ii/(~oiiro/o~~.Srroudsburg Dowden, Sigoyneau-Ruscll, D. 144 la First el idence of Hucchison and Ross, Inc. l[ulticut~crculara (Ilammalia) in che I[esozoic of and \-an 1-alen, L. lc>6j.Cretaceous ~uammalsfrom

.Ifrica. .\;,irl,s .fih16!ich /io- G'c,o/oxic~iriid Pi'ii/ioi~rn/o~it: \[ontana. Scit~ii~~c148. 20-22-.

I lo~ii~tiht~fit1991: 1 1017 j. S~ala!, FS. 1443~.Pedal e~olurionof 11iammals In che IOOlb. Dkcou~ercedc \)rc~nierluammifCre r~.il~ospllc- Ileso~oic:resrs for tasic relationships, pp. 108-1 !S in niquc du .\[ksozo'iquc africain. Coiiipr~,.i Kt,i/i/ii.i ill, Szala!; ES., Sol-acek, 111. and .\lcKenna, I1.C. (cds.),

/:-l~.i~i/c:itrit~L/I,J. Si./c~/ic.l~i, 1'ilri.i 3 1 3. I 63 ;-I 640. I liii~ii~iii/ I/o .I lt,so:.oi~. Ijrfin~iirinrioti, lvv5. Furcher data ancl retlcsions on rlie rrihosphenid 1 fii/tiriiht~rci~/iirc~~-,I ~~ji/~t~l'~~il'J~, E//rll' */-h~~riiiii.~ i11ii1 ~nanimals(l'ril~ocheria) fro111 rhe Earll- Cretaceous of I I~ii:iii/~iir/.~-.Sew 1 ork: S\>rinyer\'erl:~y.

llorocco. /~I~//LTII~dl/ .l1iisci1111II~III~III// d Hi.~.toirt, iiiitii- -IYc~jl>. \:;,O/!I~;~II/~II:J~/fi.i~oi:)~ of thl, Iliii:iii/~~ir/.ii111i1 ilii

r~~//l~,I'irr1s4 s6r. 16: 7c)l-?l 7. ~l~ll/~',~'l.iOf' t/lt' ~).i~t'O/~lx~~/l/(~/!1111~17l'~t'~J~. NCIV 1-Ork: Dashzcl-ep, D. anci Russell, D.E. IO')?. Further data on Caml~ridgcCnil-ers~tl- Prey?: 11 +4S1 pp.

/'i.okt~7iiii1/t,.rrt..r (\Ia~nmalia,Euchcria iiil.. .it~i/.ifrom the and .\[ckenna, \1.<:. 14-1. I3epinnin~of [he age of

Early (:recaccous of .\Ion%olia. /loo/o~ic.ii.Scriptir 21: rualn~llalsill \sia: chc L;lre Paleocene <;ashaco fauna, 705-7ov. \ [oll~olia.. ~llit'i~i(.~l/ ~~1151'11111 !I/' \flll!i.ll/ ~~ISTOI:)'/IIl//l'~lll and l.:nso~ll, P. 1004. Dtcou~erte,dans Ic Grou11 de 144: 260--3 IS. Purheck (Bcrriasicn, .Inyleterre), du plus ancien arld Trohnlo~,B..I. 1006. 7'he ~nor\lholopyof Lace tk~noignagcdc I'esistence de 1narnlnif6rer tribosphe- C~.etaceous.I.iinr/~e~riir~~i, and tllc c;~rl!- ph!-loyen!. and

niclue~Coitipte~i Kt~iii/its i/tz /:ici~i/t~iiiit,i1t.i Scir.iil.(,i; l'iii-i~. paleohiolop!. of \[etatlicria. .fi~iii-iiii/ ~f 1 ~rtchri~tc, 319, skrie 11: 833-838. /'ii/t~oiito/o~j16: 4-t;Oi). Z klELl\-Jll5OROtl Skl ttlil

Taquet, P. 1994. LEmpreinre des I)ir~osaurc.s.Paris, Editions Sytnposiziwl 011 .Ilesozoic 7i.rl-ei.trial Ecosystems and Biota. OdileJacob, 363 pp. Shorrpapel-s, Ocean Press, Beijing. Tatarinov, L.P. 1901. [On an unusual rnamnialian tooth Wible, J.R. 1900. Petrosals of Late Cretaceous marsupials from the bfongolian Jurassic]. Paleontolopicheskii from Sorth .\merica, and a cladistic analysis of the Zhurna11994: 97-1 05. petrosal in therian mammmals. .7ounzal of I>rtebr/rte Trofi~nov,B.A. 1975. [New data on Ruginbaatar Kielan- Pnleo~ztolo~~10: 18 3-2 05. Jaworowska et Sochava, 1969 (3lammalia, -1901. Origin of &Iamn~alia:the craniodental e~.idence Multituberculata) from 1Iongolia.l Trudj So~mrsruoi reexamined. yournalo/ Irrebrure Ptileontolo~y11: 1-18. So~~etrko-,Zlongol?koiP~zleontologicbeskoi Lk.rpeditsii 2: -and Hopson, J..\. 1993. Basicranial evidence for early 7-1 3. mammal ph!-logeny, pp. 15-62 in Szalay, F.S., -1978. [The first triconodonts (hIammalia, So~.acek,X1.J. and XlcKenna, X1.C. (eds.), !Mammal Triconodonta) from Xlongoliaj. Doklady,i.\'SSSR 243: Phylogeny: .Ili.sozoic D~firentiatio~~..Zfultituberculati~s, 213-216. Mo~~otremaEarly Tberians, and .Marsupirrls. New York: -1080. [Multituberculata and Symnietrodonta from the Springer Verlag. Lower Cretaceous of blongolia.] Doklad? -4.V SSSR , Rougier, G.W., Novacek, hI.J., hlcKenna, M.C. and 251: 209-21 2. Dashze~.eg,D. 1995. .\ mammalian petrosal from the -1907. .4 new generic name Gobiotberiodon for a symmet- Early Cretaceous of hlongolia: implications for the rodont mammal Gobiodon Trofimol; 1980. .icta evolution of the ear region and malnmaliamorph Palreontologica Polonica 42:196. relationships. .Itnerzca~z-2luseum 'vhaitates 3 149: 1-19. andSzalay, F.S. 1994. New Cretaceous marsupial from Yabe, H. and Shikama, T. 1938. .\ newJurassic Xlammalia hlongolia and the early radiation of XIetatheria. from south Xlanchuria. .7apanes~~ournalof Geolou and Proceedings of the Vational.4cademy of Scienres, C.S.,19 1: Geography 14: 353-357. 12569-12573. Yadagiri, P. 1985. .An amphidontid symmetrodont from the Wang, Y., Hu, I-, Zhou, hl. and Li, C. 1995. Xlesozoic Early Jurassic Kota Formation, India. Zoological mammal localities in western Liaoning, northeast yournal of the I.innean Society 85: 11141 7. China, pp. 221-227 in Sun, A. and Wang, Y. (eds.) Sixth