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1
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Structure of the K-T mammal radiation in North America: speculations on turnover rates and trophic structure

100%
Archibald J. D.
Acta Palaeontologica Polonica
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1983
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tom 28
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nr 1-2
Preliminary results from Montana and New Mexico (USA) indicate that appearance rates for mammal species increase from the latest Cretaceous (Lancian) into the early Paleocene (Puercan) with a slight decline into the middle Paleocene (Torrejonian). Disappearance rates decline over the same interval and equal appearance rates by the Torrejonian. These results are the opposite of those found by Van Valen (1978). Some groups (condylarthrans) have more frequent speciation events and . shorter species durations than suggested by Stanley (1979). The overall appearance rate for the K-T interval is very similar to that for the Paleocene-Eoeene transition (both about 1 sp./10⁴ yrs.). The overall disappearance rate for the K-T interval (1.4 sp./10⁴ yrs.) is markedly higher than for the Paleocene—Eocene transition (0.5 sp./10⁴ yrs.). With the extinction of dinosaurs, “guilds” of small mammals are re-established and new “guilds” form after about 2.5X10⁵ years. Appearance rates are highest during guild establishment.
2
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A new periodical on mammals

100%
Archibald J. D.
Acta Palaeontologica Polonica
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2003
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tom 48
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nr 1
3
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Pruning and grafting on the mammalian phylogenetic tree

100%
Archibald J. D.
Acta Palaeontologica Polonica
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1999
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tom 44
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nr 2
4
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New material and reinterpretation of the Late Cretaceous eutherian mammal Paranyctoides from Uzbekistan

63%
Averianov A. O., Archibald J. D.
Acta Palaeontologica Polonica
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2013
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tom 58
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nr 1
Paranyctoides aralensis, based on a partially known set of lower postcanines from the Turonian Bissekty Formation of Uzbekistan, is proposed to be a junior subjective synonym of Sailestes quadrans, itself based on an M1 from the same stratigraphic unit. As a result, the latter taxon is recombined as Paranyctoides quadrans comb. nov. Based on newly col− lected or recognized specimens, we show that this species has four lower incisors, including a procumbent i1 and a rela− tively small i4, as well as five double−rooted premolars, the smallest of which (p3) can be lost ontogenetically. The p5 of this species is premolariform, rather than molariform as previously thought based on an erroneous identification, and re− sembles North American species of Paranyctoides in the presence of a small, cingulid−like paraconid and a distal talonid cusp, as well as the absence of a metaconid. The lower molars of Paranyctoides are unique among Late Cretaceous eutherians in having a larger, lingually placed paraconid. Paranycoides probably is the sister taxon of the Late Cretaceous Zhelestidae.
5
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Paranyctoides and allies from the Late Cretaceous of North America and Asia

63%
Archibald J. D., Averianov A. O.
Acta Palaeontologica Polonica
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2001
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tom 46
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nr 4
Paranyctoides is represented by three named, and possibly four unnamed species in the Late Cretaceous, North America. P. aralensis from the Late Cretaceous of Dzharakuduk, Uzbekistan, belongs in this or a closely allied taxon. Lower molars have low trigonids, well-developed paraconids not appressed against metaconids, talonids on ml-2 as wide or wider than trigonids, hypoconulids often closer to entoconids than to hypoconids. Only two upper molars are known, both have comparatively narrow crowns with wide stylar shelves and stylar cusps, paracone and metacone separated, conules well developed, and protocone low. Pre- and postcingula vary from narrow in one, Sailestes quadrans, to wide in the other, Paranyctoides sp. Sailestes quadrans may be an metatherian. All known species of Paranyctoides from North America have a submolarifom ultimate premolar while Gallolestes pachymandibularis, also from North America, has molars not unlike those in Paranyctoides but may have an ultimate premolar with a molarifom trigonid. A specimen from Dzharakuduk referable to P. aralensis is suggestive of such morphology. At least P. aralensis had five premolars with the third reduced as in 'zhelestids'. These findings increase the Late Cretaceous North American/Asian ties even more for eutherians, now with 'zhelestids' and the Paranyctoides/Gallolestes clades known from both.
6
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New specimens of the multituberculate mammal Uzbekbaatar from the Late Cretaceous of Uzbekistan

63%
Averianov A. O., Archibald J. D.
Acta Palaeontologica Polonica
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2006
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tom 51
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nr 2
Uzbekbaatar Kielan−Jaworowska and Nessov, 1992 is among the rarest mammals and the only multituberculate in the diverse, eutherian dominated Bissekty (Turonian) and Aitym (?Coniacian) local faunas, Kyzylkum Desert, Uzbekistan. New material from the Bissekty local fauna, suggests that only one multituberculate species, Uzbekbaatar kizylkumensis Kielan−Jaworowska and Nessov, 1992 is present in the Bissekty fauna. A newly collected p4 is better preserved than the holotype and demonstrates presence of the posterolabial cusp in the p4 of Uzbekbaatar. New material of Uzbekbaatar is consistent with placement of this taxon within the basal cimolodontan “Paracimexomys group.”
7
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Late Cretaceous asioryctitherian eutherian mammals from Uzbekistan and phylogenetic analysis of Asioryctitheria

63%
Archibald J. D., Averianov A. O.
Acta Palaeontologica Polonica
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2006
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tom 51
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nr 2
Four small asioryctitheres at Dzharakuduk (Turonian), Uzbekistan are Daulestes kulbeckensis (= Kumlestes olzha), D. inobservabilis (= Kennalestes? uzbekistanensis), Uchkudukodon (gen. nov.) nessovi and Bulaklestes kezbe. Uchkudukodon nessovi is one of the smallest therians (molars about 1 mm long). Lower canine is two−rooted in Uchkudukodon gen. nov. and Bulaklestes(uncertain in Daulestes). All lower premolars in all four species are double−rooted. Teeth identified as dp1, p2 and dp2 in holotype of Uchkudukodon nessovi (McKenna et al. 2000) are here identified c, p1, and p2. A phylogenetic analysis weakly supported Asioryctitheria by four synapomorphies: conular basins become distinct, the number of roots reverts to two on the lower canine, the p5 becomes longer than p4, and the metaconid on p5 is reduced and lost. Other characters diagnostic of asioryctitheres are four upper and lower premolars (arguably five upper premolars in juvenile Kennalestes), P4 has a protocone swelling or protocone, some asymmetry of the stylar shelf on M1–2, the paraconule on M1–3 is distinctly closer to the protocone than is the metaconule, protocone is of moderate height on M1–3 (70–80% of paracone or metacone height), Meckel’s groove is absent, and the mandibular foramen opens into a smaller depression on lingual side of mandibular ascending ramus. Asioryctes and Ukhaatherium are placed in Asioryctinae and along with Kennalestes are placed in Asioryctidae. Kennalestidae Kielan−Jaworowska, 1981 is a junior subjective synonym for Asioryctidae Kielan−Jaworowska, 1981. Because of uncertainties in the analysis, the positions of Daulestes, Uchkudukodon gen. nov., and Bulaklestes cannot be determined beyond referral to Asioryctitheria.
8
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A new eutherian mammal from the Late Cretaceous of Kazakhstan

51%
Averianov A., Archibald J. D., Dyke G. J.
Acta Palaeontologica Polonica
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2014
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tom 59
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nr 3
A dentary fragment containing the last two molars (m2–3) from the Late Cretaceous (Santonian–?Campanian) Bostobe Formation exposed at the locality of Shakh Shakh, northeast Aral Sea region, Kazakhstan, is attributed to a new taxon of Zhelestidae, Zhalmouzia bazhanovi Averianov and Archibald gen. et sp. nov. This specimen is only the second mammal described from Shakh Shakh, the unidentifiable eutherian Beleutinus orlovi Bazhanov, 1972, being the first, and it is only the fifth Mesozoic mammal named from Kazakhstan. Zhalmouzia Averianov and Archibald gen. nov. belongs to the endemic clade of Middle Asian zhelestids (Zhelestinae), better known from the Turonian of Uzbekistan.
9
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Petrosal bones of placental mammals from the Late Cretaceous of Uzbekistan

51%
Ekdale E. G., Archibald J. D., Averianov A. O.
Acta Palaeontologica Polonica
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2004
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tom 49
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nr 1
Petrosal bones representing “Zhelestidae” and Kulbeckia (“Zalambdalestidae”) were recovered from the Late Cretaceous of Uzbekistan and are formally described. The “zhelestid” petrosal retains several characters ancestral to eutherians (if not more basally in the mammalian phylogeny),including a prootic canal,a lateral flange,and a less elliptical fenestra vestibuli. The only other eutherian taxon to retain these structures is the Early Cretaceous Prokennalestes. No characters unique to “zhelestids” and ungulates were found in the “zhelestid” petrosal. The petrosal of Kulbeckia shares several characters in common with other “zalambdalestids” (such as Zalambdalestes and Barunlestes),as well as Asioryctes and Kennalestes,including a curved ridge connecting the crista interfenestralis to the caudal tympanic process,and presence of a “tympanic process” at the posterior aspect of the petrosal.
10
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Placental nature of the alleged marsupial from the Cretaceous of Madagascar

51%
Averianov A. O., Archibald J. D., Martin T.
Acta Palaeontologica Polonica
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2003
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tom 48
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nr 1
A recently (Krause 2001) reported fragmentary mammalian lower molar (University of Antananarivo, UA 8699) from the Late Cretaceous (Maastrichtian) of Madagascar, was attributed to Marsupialia, for which far reaching paleobiogeographical conclusions were made. The five characters used to identify UA 8699 as a marsupial are not exclusive to Late Cretaceous marsupials, but are found also in some placental mammals, notably in Late Cretaceous ungulatomorph zhelestids, known from various Upper Cretaceous strata in Asia, Europe, and NorthAmerica (Nessov et al. 1998). Identification of UA 8699 as a zhelestid placental is in keeping withmyriad other faunal similarities between Europe and Africa/Madagascar.
11
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Mammalian distal humeri from the Late Cretaceous of Uzbekistan

45%
Chester S. G. B., Sargis E. J., Szalay F. S., Archibald J. D., Averianov A. O.
Acta Palaeontologica Polonica
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2010
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tom 55
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nr 2
199-211
We describe mammalian distal humeri recovered from the Bissekty Formation, Dzharakuduk, Kyzylkum Desert, Uzbekistan (90 Ma). Isolated elements were sorted into groups that likely correspond to species (or genera). These groups were allocated to taxa known mostly from the dentition, petrosals, and/or tarsals at this site. We identified one humerus of a multituberculate and one of a zalambdalestid. Several eutherian humeri have been tentatively assigned to Zhelestidae based on their dissimilarity to zalambdalestids and the abundance of zhelestids in the dental record. The zalambdalestids and zhelestids were probably terrestrial. At least two metatherian taxa have also been identified, and both were likely arboreal. Although the dental record suggests twelve eutherian species and only one metatherian, crurotarsal evidence supports the presence of at least four metatherian species at Dzharakuduk. The humeri analyzed here also provide support for the presence of multiple metatherians in the fauna, further demonstrating that postcrania are critical to understanding the taxonomic diversity present at these Late Cretaceous localities.
12
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Therian femora from the Late Cretaceous of Uzbekistan

45%
Chester S. G. B., Sargis E. J., Szalay F. S., Archibald J. D., Averianov A. O.
Acta Palaeontologica Polonica
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2012
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tom 57
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nr 1
Femora referable to metatherians and eutherians recovered from the Bissekty Formation, Dzharakuduk, Kyzylkum Desert, Uzbekistan (90 Mya), are described. Fourteen isolated specimens were sorted based on size and morphology into groups that likely correspond to the species level or higher. Groups were then tentatively assigned to taxa known from teeth, petrosals, and/or other postcrania at these localities. One distal femur of a small arboreal metatherian, and several eutherian distal femora that probably represent zhelestids and/or zalambdalestids were identified. With the exception of one proximal femur that is similar in some aspects to the zalambdalestid Barunlestes, and a previously described multituberculate specimen, all other proximal femora from the Bissekty Formation exhibit a metatherian−like morphology. The dental record currently suggests the presence of twelve eutherian species and only one metatherian at Dzharakuduk, whereas the humeral and crurotarsal evidence supports the presence of at least two or four metatherian species, respectively. Given the sample size of the proximal femora, the morphological diversity present, and the overwhelming presence of eutherians at these localities, it is highly unlikely that the overwhelming majority of proximal femora actually represent metatherians. Therefore, this sample may suggest that the metatherian proximal femoral condition is primitive for Theria and that some eutherian taxa (probably including Zhelestidae, which are dentally most abundant at these localities) retain this condition.
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