[PaleoEntomology • 2023] Ceratophyus yatagaii • The First Fossil of Ceratophyus (Coleoptera: Geotrupidae) from the Middle Pleistocene Shiobara Group of Nasushiobara City, Tochigi Prefecture, Japan

 Ceratophyus yatagaii 

Aiba & Král, 2023

DOI: 10.2517/PR230013 

  Researchgate.net/publication/376207398

Abstract

A new fossil species of the genus Ceratophyus Fischer von Waldheim, 1824, was discovered in the Shiobara Group (Chibanian, ca. 0.3 Ma) of the Middle Pleistocene distributed in Nasushiobara City, Tochigi Prefecture, Japan. This fossil is female, large in size (ca. 25 mm), well preserved, and nearly completely preserved. The genus Ceratophyus is not distributed in modern Japan. This is the first discovery of a fossil of the genus Ceratophyus and the first report of a certain extinct species from the Shiobara Group. The genus Ceratophyus is now fragmentarily distributed in the Holarctic region of the world, but the discovery of the fossil suggests that the genus was widely distributed throughout the world during the Middle Pleistocene. Notably, the fossil was discovered by a student during a high school lesson from a rock brought into the classroom. We consider the examined fossil to be morphologically different from all known extant species of the genus, and therefore we describe it as Ceratophyus yatagaii sp. nov.

KEYWORDS: Ceratophyus, fossil insect, Geotrupidae, Middle Pleistocene, Siobara Group

Ceratophyus yatagaii sp. nov.

 

Hiroaki Aiba and David Král. 2023. The First Fossil of Ceratophyus (Coleoptera, Geotrupidae) from the Middle Pleistocene Shiobara Group of Nasushiobara City, Tochigi Prefecture, Japan. Paleontological Research. 28(3); 265-272. DOI: https://doi.org/10.2517/PR230013  

 Researchgate.net/publication/376207398_The_first_fossil_of_Ceratophyus_from_the_Middle_Pleistocene_Shiobara_Group_of_Nasushiobara_Tochigi_Prefecture_Japan

慶應高校の3年生が授業中に見つけた30万年前の昆虫化石、新種と認定

 news.mynavi.jp/techplus/article/20231211-2838656/

Fossil found in Japan school class confirmed as new beetle species

 www.japantimes.co.jp/news/2023/12/12/japan/science-health/japan-new-beetle-species-found/

[PaleoMammalogy • 2023] Reproduction of A Fossil Rhinoceros from 18 mya and Origin of Litter Size in Perissodactyls

 

in Lu, Deng, Rummy, Zheng et Zhang, 2023. 

DOI: 10.1016/j.isci.2023.107800 

Illustration by Chung-Tat Cheung facebook.com/ChungTatCheung

  

Highlights: 

• Fossil rhinoceros from 18 mya is monotocous

• Reproductive traits in living rhinoceroses have been evolving at least since 18 mya

• Litter size of perissodactyls has an origin of singleton pregnancy

Summary

Reproductive strategy is among the most important characteristics of organism. Here, we report reproductive strategy of singleton pregnancy of a fossil rhinoceros, Plesiaceratherium gracile, from 18 mya of the Shanwang Basin, China. Dental and body development data revealed that after birth, the calf of P. gracile is breastfed for 2–3 years; at approximately 5 years of age, when the M2 tooth is slightly worn, the female has already reached sexual maturity and attained a size close to that of an adult and could give birth to the first calf. Furthermore, given litter size is phylogenetically conservative and closely correlates with body size, we conclude that the litter size of perissodactyls is determined by the singleton pregnancy since the Eocene. By contrast, other reproductive traits are highly variable and have a different pace of evolution, and traits observed in living rhinoceroses have been evolving at least since 18 mya.

 

Xiao-Kang Lu, Tao Deng, Paul Rummy, Xiao-Ting Zheng and Yuan-Tao Zhang. 2023. Reproduction of A Fossil Rhinoceros from 18 mya and Origin of Litter Size in Perissodactyls. iScience. 26(10); 107800. DOI: 10.1016/j.isci.2023.107800

  facebook.com/ChungTatCheung/posts/6646226455415527

[PaleoMammalogy • 2023] A Macroevolutionary Pathway to Megaherbivory

in Sanisidro, Mihlbachler & Cantalapiedra, 2023.

 DOI: 10.1126/science.ade1833 

 twitter.com/Canta_Lab

Abstract

Several scenarios have been proposed to explain rapid net size increases in some early Cenozoic mammalian lineages: sustained and gradual directional change, successive occupation of adaptive zones associated with progressively larger body sizes, and nondirectional evolution associated with branching events in combination with higher diversification potential of the larger lineages. We test these hypotheses in brontotheres, which are among the first radiations of mammals that consistently evolved multitonne sizes. Body-mass evolution in brontotheres mainly occurred during speciation and had no preferential direction. Long-term directional change stemmed from the higher survival of larger lineages in less-saturated herbivore guilds. Our study emphasizes the role of differential species proliferation in explaining the long-term phenotypic trends observed in the fossil record, which are more than an accumulation of steady microevolutionary changes.

Editor’s summary: 

After the extinction of large dinosaurs at the end of the Cretaceous, many mammals underwent a rapid increase in size. Several hypotheses for this change have been put forward, with much debate about the drivers. Sanisidro et al. looked at the record of body size in brontotheres, large herbivorous mammals from the Eocene that experienced orders of magnitude changes in size. The authors saw no evidence for directional selection, but instead found a pattern of increased survival of larger species caused by reduced competition with other herbivores in their niches. Thus, over time, the increase in body size in these mammals was caused by the macroevolutionary process of species sorting. —Sacha Vignieri

Oscar Sanisidro, Matthew C Mihlbachler and Juan L Cantalapiedra. 2023. A Macroevolutionary Pathway to Megaherbivory. SCIENCE. 380, 6645; 616-618. DOI: 10.1126/science.ade1833

  twitter.com/Canta_Lab/status/1656720984617934850

  phys.org/news/2023-05-differential-species-proliferation-key-evolutionary.html

[PaleoEntomology • 2023] A diverse Cenozoic insect assemblage in Thailand

in Warapeang, Deesri, Khalloufi, Manitkoon & Srisuk. 2023. 

DOI: 10.1080/08912963.2023.2165920 

facebook.com/PRCMSU

 facebook.com: Sita Manitkoon

 

ABSTRACT

In Western Thailand, Miocene shales from Wang Kaew, in the Mae Sot basin, have yielded a diverse insect assemblage comprising 115 articulated specimens. In this preliminary review, 15 subcomplete specimens are studied and referred to at least eight forms belonging to five orders (Coleoptera, Diptera, Hymenoptera, Orthoptera, and Hemiptera). Coleoptera are represented by very nicely preserved specimens of weevils (Curculionidae). Diptera are known by three different taxa referred to Bibionidae, Sciaridae and Brachycera. Hymenoptera are known by representatives of Vespidae and Formicidae. Orthoptera are represented by a single specimen of uncertain affinities and Hemiptera by one Gerrinae. This insect assemblage is the most complete ever reported in Southeast Asia during the Cenozoic.

KEYWORDS: Fossil insects, Mae Sot Basin, Miocene, Thailand

Prapasiri Warapeang, Uthumporn Deesri, Bouziane Khalloufi, Sita Manitkoon and Paladej Srisuk. 2023. A diverse Cenozoic insect assemblage in Thailand. Historical Biology: An International Journal of Paleobiology. DOI: 10.1080/08912963.2023.2165920

facebook.com/PRCMSU/posts/626182459510255

  facebook.com/sitaaqua12/posts/10160518695774642

[PaleoOrnithology • 2022] Cryptogyps lacertosus • A New Look at An Old Australian Raptor places “Taphaetus” lacertosus de Vis 1905 in the Old World vultures (Accipitridae: Aegypiinae)

Cryptogyps lacertosus (de Vis, 1905)

Cryptogyps Mather, Lee and Worthy 2022 gen. nov.

in Mather, Lee & Worthy, 2022. 

DOI: 10.11646/zootaxa.5168.1.1

  twitter.com/Ellenaetus

Abstract 

The Australian Pleistocene fossil record of the Accipitridae (hawks, eagles and Old World vultures) is sparse and poorly known. Only two extinct confirmed accipitrid species have been described for this time period; both have received little investigation since their description. One is “Taphaetus” lacertosus de Vis, 1905, described from a distal humerus and a quadrate from north-eastern South Australia. While this species was verified as an accipitrid in subsequent studies, its more precise taxonomic affinities have remained conjectural. In this study, a new analysis incorporating newly referred material and phylogenetic analyses using a wide range of accipitriforms reveals that the lectotype humerus of “T.” lacertosus is an Old World vulture in the subfamily Aegypiinae. The associated quadrate, one of two original syntypes from which de Vis named this species, is of an indeterminate species of ardeid. We erect the novel genus Cryptogyps, to accommodate the species ‘lacertosus’, as it cannot be placed in Taphaetus de Vis, 1891, because the type species of this genus, Uroaetus brachialis de Vis, 1889, was transferred back to the genus Uroaetus, a synonym of Aquila Brisson, by de Vis in 1905. Further, U. brachialis is now considered a synonym of Aquila audax (Latham, 1801). Moreover, Taphaetus de Vis, 1891 is a senior homonym of Taphaetus de Vis, 1905, type species Taphaetus lacertosus de Vis, 1905, making the 1905 version of the genus unavailable. Newly referred fossils from Wellington Caves (NSW) and the Nullarbor Plains (WA) reveal this taxon had a wide geographical range across Pleistocene Australia. The referred tarsometatarsus lacks hyper-developed trochleae, indicating that Cryptogyps lacertosus (de Vis, 1905) comb. nov., was probably a scavenger like other aegypiines. Identification of Cryptogyps lacertosus as an aegypiine significantly expands the palaeogeographical range of the Old World vultures, hitherto unknown in Australia. The avian guild of large, obligate scavenging birds of prey, is currently absent in the modern Australian biota, but its former presence is not surprising given the megafauna-rich communities of the Pleistocene.

Key words: Pleistocene fossil birds, Accipitriformes, extinction, scavengers, biogeography, Australia

Cryptogyps Mather, Lee and Worthy 2022 gen. nov.

Type species: ‘Taphaetus’ lacertosus de Vis, 1905: 

Annals of the Queensland Museum 6: 4, pl. 1, fig. 1.

Etymology: The name is derived from a combination of the Ancient Greek words ‘kryptós’ (hidden) and ‘gýps’ (vulture), in reference to the fact that this taxon was known for over 100 years but was generally believed to be an eagle. Cryptogyps also relates to the word ‘crypt’, a word used to describe an underground burial chamber, referencing the discovery of the new material in caves.

Conclusion: 

“Taphaetus” lacertosus de Vis, 1905, is confirmed to be a valid species of extinct accipitrid, for which the new genus Cryptogyps is erected. Cryptogyps lacertosus (de Vis, 1905) is shown to be an aegypiine vulture that was widespread in southern Australia in the middle to late Pleistocene. The presence of Old World vultures (Aegypiinae) among Pleistocene Australian accipitrids indicates that their taxonomic and ecological diversity was significantly greater then than it is today; the extinction of Cryptogyps lacertosus likely had a distinct impact on those ancient ecosystems.

Ellen K. Mather, Michael S. Y. Lee and Trevor H. Worthy. 2022. A New Look at An Old Australian Raptor places “Taphaetus” lacertosus de Vis 1905 in the Old World vultures (Accipitridae: Aegypiinae). Zootaxa. 5168(1); 1-23. DOI: 10.11646/zootaxa.5168.1.1

  twitter.com/Ellenaetus/status/1549537176374743041

  

[PaleoEntomology • 2022] New Species of belytine and diapriine Wasps (Hymenoptera: Diapriidae) from Eocene Baltic Amber

Doliopria baltica

Brazidec & Vilhelmsen, 2022

DOI: 10.5852/ejt.2022.813.1733

  twitter.com/manu_bzd 

ABSTRACT

The fossil diversity of Diapriidae in Baltic amber, dated Upper Eocene, has been poorly investigated. However, some studies suggest that this family was already diversified at this time. This is supported by our present study of the Baltic amber collection of the Natural History Museum of Denmark, from which we describe and figure ten new species belonging to the subfamilies Belytinae: Belyta knudhoejgaardi sp. nov., Cinetus breviscapus sp. nov., Cinetus elongatus sp. nov., Pantoclis globosa sp. nov., Pantolyta augustinusii sp. nov., Pantolyta chemyrevae sp. nov., Pantolyta similis sp. nov.; and Diapriinae: Basalys villumi sp. nov., Doliopria baltica sp. nov. and Spilomicrus succinalis sp. nov. The diversity of extant genera observed leads us to propose an origin in the early Cenozoic for these taxa. The fossil record of the Diapriidae in Baltic amber is also summarized.

Keywords: Belytinae, Diapriinae, fossil record, Bartonian–Priabonian, Cenozoic

Belyta knudhoejgaardi sp. nov. Holotype (NHMD-608408).

Pantolyta similis sp. nov., holotype  (NHMD-608468).

Doliopria baltica sp. nov., holotype (NHMD-608374).

Manuel Brazidec and Lars Vilhelmsen. 2022. New Species of belytine and diapriine wasps (Hymenoptera: Diapriidae) from Eocene Baltic Amber. European Journal of Taxonomy. 813(1); 57–86.  DOI: 10.5852/ejt.2022.813.1733

  twitter.com/manu_bzd/status/1514181810435022851

[PaleoMammalogy • 2021] Eusmilus adelos • The Largest Hoplophonine (Carnivora: Nimravidae) and A Complex New Hypothesis of Nimravid Evolution

Eusmilus adelos

 Barrett, 2021

DOI: 10.1038/s41598-021-00521-1 

twitter.com/nimravenous 

skeletal reconstruction by Dhruv Franklin  twitter.com/DhruvFranklin

Abstract

Nimravids were the first carnivorans to evolve saberteeth, but previously portrayed as having a narrow evolutionary trajectory of increasing degrees of sabertooth specialization. Here I present a novel hypothesis about the evolution of this group, including a description of Eusmilus adelos, the largest known hoplophonine, which forces a re-evaluation of not only their relationships, but perceived paleoecology. Using a tip-dated Bayesian analysis with sophisticated evolutionary models, nimravids can now be viewed as following two paths of evolution: one led to numerous early dirk-tooth forms, including E. adelos, while the other converged on living feline morphology, tens of millions of years before its appearance in felids.

Partial skeleton of USNM 12820, Eusmilus adelos with shaded known elements. Cranial abbreviations: fr frontal, na nasal, mp mastoid process, (A) cn carnassial notch, mc main cusp of P3, pa paracone, pcc posterior cingular cusp of P3, ps parastyle; (B–D) bis brachialis insertion site, lg lateral groove of ulna, rn radial notch, sln semilunar notch, (E–G) ce capitular eminence of radius, rt radial tuberosity, (H–J) dpc delto-pectoral crest, of olecranon fossa, sc supinator crest (brachial flange), *remnants of bridge enclosing epicondylar foramen. Eusmilus adelos skeletal reconstruction by Dhruv Franklin.

Tip-dated Bayesian phylogeny of the Nimravidae, outgroups (save Tapocyon) removed. Two main clades were recovered, the Hopliphoninae and Nimravinae, the latter of which includes all barbourofelin taxa. Color gradient reflects maximum-likelihood estimation of ancestral body mass. Additional nodal values (e.g., posterior probability, divergence dates) can be found in Supplementary.

Systematic palaeontology

Carnivora 

Nimravidae 

Eusmilus 

Eusmilus adelos sp. nov.

Holotype: Smithsonian National Museum of Natural History, Washington D.C., USA (USNM) 12820: partially crushed cranium, parts of both dentaries, atlas, axis, 3rd, 5th and 7th cervical vertebrae, three lumbar vertebrae, left: scapula, distal humerus, proximal and distal ends of radius, proximal ulna (Figs. 1, 2, 3, Supplementary Figs. S1–S3).

Etymology: From the Greek adelos, for unseen, unknown, or secret. The specific epithet refers to the unclear taxonomic affiliations these specimens have had in their more than 85 year history of publication. 

Paul Zachary Barrett. 2021. The Largest Hoplophonine and A Complex New Hypothesis of Nimravid Evolution. Scientific Reports. 11, 21078. DOI: 10.1038/s41598-021-00521-1

 twitter.com/nimravenous/status/1453107573788344320

 twitter.com/DhruvFranklin/status/1453122170784256004

[PaleoOrnithology • 2021] Archaehierax sylvestris • An Exceptional Partial Skeleton of A New Basal Raptor (Accipitriformes: Accipitridae) from the late Oligocene Namba Formation, South Australia

Archaehierax sylvestris

Mather, Lee, Camens & Worthy, 2021

DOI: 10.1080/08912963.2021.1966777

 

ABSTRACT

The Australian pre-Pleistocene fossil record of Accipitridae (eagles, hawks, old-world vultures) comprises one latest Oligocene or early Miocene and one middle Miocene species, each represented by partial bones. Globally, most fossil accipitrids are based on single bones. The recent discovery of an older and considerably more complete accipitrid from late Oligocene sediments in Australia is therefore significant. It is derived from the Pinpa Local Fauna from the Namba Formation at Lake Pinpa, South Australia (~26–24 Ma). The fossil, described as Archaehierax sylvestris gen. et sp. nov., represents a raptor that was larger than the black-breasted buzzard Hamirostra melanosternon but smaller and more gracile than the wedge-tailed eagle Aquila audax. Comprehensive morphological and molecular phylogenetic analyses resolved Archaehierax as a basal accipitrid, not closely related to any living subfamily and perhaps the sister taxon to all other accipitrids exclusive of elanines. Relatively short wings similar to species of Spizaetus and Spilornis suggest it was adapted for flight within enclosed forests. Additional accipitrid fossils from the Namba Formation, a distal femur and a distal humerus, are incomparable with the holotype of A. sylvestris; they may represent distinct species or smaller individuals of the new taxon.  

KEYWORDS: Lake Pinpa, Accipitriformes, Cenozoic fossil birds, accipitrid evolution, Australia

Skeleton of an osprey by Eyton (1867) with shaded sections indicating which bones are preserved in the fossil of Archaehierax sylvestris.

 A comparison of the prepared fossil tarsometatarsus (foot bone) and a hypothesised silhouette of Archaehierax sylvestris (left) compared to the wedge-tailed eagle Aquila audax (right).

The scale bar is 10 mm long.

Systematic palaeontology

Class Aves Linnaeus, 1758

Order Accipitriformes Vieillot 1816 Family Accipitridae Vigors, 1824

Subfamily: Archaehieraxinae subfam. nov.

Type genus: Archaehierax gen. nov.

Remarks: 

The fossil is identified as an accipitrid due to the following combination of characters: Skull – Rostrum deep and narrow, with hooked tip and a large, broad nasal aperture; Tibiotarsus – Pons supratendineus ossified, aligned steeply transversely, medially placed, with unbranched canalis tendinosus, and distal condyles much wider than craniocaudally deep; Tarsometatarsus – Robust, with monosulcate hypotarsus, the lateral and medial hypotarsal crests widely separated and trochleae metatarsorum splayed both medially and laterally, and dorsally arched in distal view; Foot – Four digits with raptorial unguals, those of digits 1 and 2 relatively large; Digit IV – phalanges 2 and 3 are very short compared to phalanx 4.

The fossil can be excluded from Falconiformes (Falconidae) and the other families of Accipitriformes (Cathartidae, Sagittariidae, Pandionidae) by the morphology of the tarsometatarsal hypotarsus cristae and sulcus. The cristae are fused or partially fused together to enclose the sulcus in Cathartidae, Sagittariidae, and Pandionidae, while in Falconidae the medial crista is connected to the shaft by a ridge that extends two-thirds of its length, features that are absent in the fossil.

Diagnosis: 

Accipitrids in which the following autapomorphic features are found: the pila medialis of the sternum dorsally separates two deep pneumatic fossae, the humerus has the caput humeri only slightly elevated proximally past the tuberculum ventralis, the tip of the processus procoracoideus of the coracoid sharply curves inwards ventrally towards the medial face of the bone, the tibiotarsus has the lateral/distal retinaculum scar in a deep fossa, the tarsometatarsus is relatively elongate with narrow trochleae metatarsorum that are separated by wide incisurae, and the incisura for the m. flexor hallucis brevis tendon is large, distinct, and extends distal to the fossa metatarsi I. In addition to this, the following features occur: the rostral tip of the rostrum is hooked below the tomial margin at a relatively shallow 30–40° angle, the quadrate has a deep, distinct foramen pneumaticum caudomediale, and the sternum has the apex carinae displaced caudally from the base of the spina externa.,

Genus Archaehierax Mather, Lee, Camens and Worthy gen. nov.

 

Etymology: Archaehierax is derived from the Greek words ‘archaios’, meaning ancient, and ‘hierax’, meaning hawk. Gender masculine.

Archaehierax sylvestris Mather, Lee, Camens and Worthy gen. et sp. nov.

Etymology: The species name ‘sylvestris’ is derived from the Greek world ‘sylvas’, meaning forest, and the Latin suffix ‘-estris’, meaning ‘belonging to’.

Ellen K. Mather, Michael S. Y. Lee, Aaron B. Camens and Trevor H. Worthy. 2021. An Exceptional Partial Skeleton of A New Basal Raptor (Aves: Accipitridae) from the late Oligocene Namba Formation, South Australia. Historical Biology: An International Journal of Paleobiology. DOI: 10.1080/08912963.2021.1966777

25-million-year-old ancient eagle ruled the roost in Australia

63 bone fossil finding in desert is one of the “best preserved” eagles ever and a very rare discovery

 eurekalert.org/news-releases/929172

[PaleoMammalogy • 2021] Mammaliaform Extinctions as A Driver of the Morphological Radiation of Cenozoic Mammals

 large Gobiconodon outcompeted the ancestors of modern mammals in the time of dinosaurs.

in Brocklehurst, Panciroli, Benevento & Benson, 2021. 

 DOI: 10.1016/j.cub.2021.04.044

 twitter.com/palaeo_neil 

Illustration: Corbin Rainbolt.  twitter.com/CorbinRainbolt

Highlights

• The therian mammal radiation is usually associated with extinctions among dinosaurs

• Mesozoic therians show greater morphological constraint than their close relatives

• The release of this constraint occurred later than the extinction of the dinosaurs

• The therian radiation was in part driven by extinctions among other mammaliaforms

Summary

Adaptive radiations are hypothesized as a generating mechanism for much of the morphological diversity of extant species. The Cenozoic radiation of placental mammals, the foundational example of this concept, gave rise to much of the morphological disparity of extant mammals, and is generally attributed to relaxed evolutionary constraints following the extinction of non-avian dinosaurs. However, study of this and other radiations has focused on variation in evolutionary rates, leaving the extent to which relaxation of constraints enabled the origin of novel phenotypes less well characterized. We evaluate constraints on morphological evolution among mammaliaforms (mammals and their closest relatives) using a new method that quantifies the capacity of evolutionary change to generate phenotypic novelty. We find that Mesozoic crown-group therians, which include the ancestors of placental mammals, were significantly more constrained than other mammaliaforms. Relaxation of these constraints occurred in the mid-Paleocene, post-dating the extinction of non-avian dinosaurs at the K/Pg boundary, instead coinciding with important environmental shifts and with declining ecomorphological diversity in non-theriimorph mammaliaforms. This relaxation occurred even in small-bodied Cenozoic mammals weighing <100 g, which are unlikely to have competed with dinosaurs. Instead, our findings support a more complex model whereby Mesozoic crown therian evolution was in part constrained by co-occurrence with disparate mammaliaforms, as well as by the presence of dinosaurs, within-lineage incumbency effects, and environmental factors. Our results demonstrate that variation in evolutionary constraints can occur independently of variation in evolutionary rate, and that both make important contributions to the understanding of adaptive radiations.

Keywords: adaptive radiation, constraint, mammal, Mesozoic, K/Pg mass extinction

Early lineages of mammal like this large Gobiconodon from Mongolia outcompeted the ancestors of modern mammals in the time of dinosaurs.

Illustration: Corbin Rainbolt.

 twitter.com/CorbinRainbolt

 

Neil Brocklehurst, Elsa Panciroli, Gemma Louise Benevento and Roger B.J. Benson. 2021. Mammaliaform Extinctions as A Driver of the Morphological Radiation of Cenozoic Mammals. Current Biology. DOI: 10.1016/j.cub.2021.04.044

 twitter.com/palaeo_neil/status/1394303018565255172

In brief: Brocklehurst et al. report that Mesozoic therians evolved under greater morphological constraint than contemporary mammaliaforms. This constraint was released later than the extinction of non-avian dinosaurs, including in therians less than 100 g. They suggest the therian radiation was in part driven by extinctions among non-therian mammaliaforms.

Mammals in the time of dinosaurs held each other back

  eurekalert.org/pub_releases/2021-05/uoo-mit051721.php

 twitter.com/CorbinRainbolt/status/1394313394178727940

[PaleoMammalogy • 2020] Oriensmilus liupanensis • A New Genus and Species of Sabretooth (Carnivora: Nimravidae: Barbourofelinae) from the middle Miocene of China suggests Barbourofelines are Nimravids, not Felids

 Oriensmilus liupanensis 

Wang, White & Guan, 2020

DOI: 10.1080/14772019.2019.1691066 

 twitter.com/JournalSystPal 

Abstract

Since the early 2000s, a revival of a felid relationship for barbourofeline sabretooths has become popular due to recent discoveries of fragmentary fossils from Africa. According to this view, barbourofelines trace their common ancestor with felids through shared similarities in dental morphology going back to the early Miocene of Africa and Europe. However, whether or not such an idea is represented in the basicranial morphology, a conservative area of high importance in family-level relationships, is yet to be tested. A nearly complete skull of Oriensmilus liupanensis gen. and sp. nov. from the middle Miocene Tongxin Basin of northern China represents the most primitive known barbourofeline with an intact basicranial region, affording an opportunity to re-examine the relationship of felids and nimravines. We also present an update on East Asian records of barbourofelines. The new skull of Oriensmilus possesses a suite of characters shared with nimravines, such as the lack of an ossified (entotympanic) bullar floor, absence of an intrabullar septum, lack of a ventral promontorial process of the petrosal, presence of a small rostral entotympanic on the dorsal side of the caudal entotympanic, and a distinct caudal entry of the internal carotid artery and nerve that pierces the caudal entotympanic at the junction of the ossified and unossified caudal entotympanics. The absence of an ossified bullar floor in O. liupanensis and its presence in those from the middle Miocene of Sansan, France thus help to bracket the transition of this character, which must have happened in the early part of the middle Miocene. Spatial relationships between bullar construction and the middle ear configuration of the carotid artery in Oriensmilus strongly resemble those in nimravines but are distinctly different from felids and other basal feliforms. Despite the attractive notion that early barbourofelines arose from a Miocene ancestor that also gave rise to felids, the basicranial evidence argues against this view.

 

Keywords: Barbourofelinae, basicranium, phylogeny, Tongxin, Cenozoic, Asia

 Skull of Oriensmilus liupanensis (IVPP V25220, holotype) from Gunziling, Tongxin County in A, right lateral; and B, dorsal views.

Order Carnivora Bowdich, 1821 

Family Nimravidae Cope, 1880 

Subfamily Barbourofelinae Schultz, Schultz and Martin, 1970 

Oriensmilus gen. nov.

 Type and only species. Oriensmilus liupanensis gen. and sp. nov. 

Etymology. ‘Oriens’, Latin for rising (of the sun), commonly referring to East Asia; ‘smile’, Greek for carving knife, in allusion to the long canine tooth of barbourofelines.

Oriensmilus liupanensis sp. nov.  

1841 Sansanosmilus palmidens (Blainville); Chen & Wu 1976, 7. 

2013b Sansanosmilus sp. (Qiu et al.); Wang et al. 2016, 798, fig. 4G.

Etymology. Refers to the Liupan Mountains (Liupan Shan); the Tongxin Basin is located at the northern foothills of the Liupan Mountains.

Type locality and horizon. IVPP V25220 is from Gunziling, about 10–12 km south of the small village Dingjia’ergou (Qiu et al. 2013b, p. 59) in the Tongxin Basin, Tongxin County, Ningxia Hui Autonomous Region; upper part of Zhang’enbao Formation (Fig. 1).

 

 

Xiaoming Wang, Stuart C. White and Jian Guan. 2020. A New Genus and Species of Sabretooth, Oriensmilus liupanensis (Barbourofelinae, Nimravidae, Carnivora), from the middle Miocene of China suggests Barbourofelines are Nimravids, not Felids. Journal of Systematic Palaeontology. 18, 9. DOI: 10.1080/14772019.2019.1691066  

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[PaleoMammalogy • 2020] Proclinodontomys dondasi • A New Echimyid Genus (Rodentia, Caviomorpha) in Central Argentina: Uncovered Diversity of A Brazilian Group of Mammals in the Pleistocene

Proclinodontomys dondasi 

Candela, Cenizo, Tassara, Rasia, Robinet, Muñoz, Valenzuela & Pardiñas, 2020

DOI: 10.1017/jpa.2019.73 

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Abstract

We describe a new extinct spiny rat, Proclinodontomys dondasi n. gen. n. sp. (Rodentia, Caviomorpha, Echimyidae), represented by a noteworthy preserved skull and mandible from the early-middle Pleistocene outcrops at the coastal cliffs of SE Buenos Aires Province (Central Argentina). Phylogenetic analyses allow us to propose that the new species described here and the already known Eurzygomatomys mordax (Winge) represent a new genus closely related to the living Euryzygomatomys spinosus and Clyomys laticeps. The new genus differs from Euryzygomatomys and Clyomys by having much more procumbent upper incisors, a more developed fossa for the M. temporalis, more flared and laterally expanded zygomatic arches, frontal less markedly expanded posteriorly, jugals much deeper anteriorly than posteriorly, with the dorsal border descending more abruptly posteriorly, smaller orbital cavity, and external auditory meatus relatively smaller and slanted upward and backward. Several features of the new species reflect a higher degree of adaptation to semifossorial habits than those of E. spinosus. The origin of the semifossorial ecomorphotype within echimyids may have been triggered by the expansion of relatively open and arid environments that arose near the Miocene-Pliocene boundary. The record of this new echimyid in Central Argentina indicates that during the early-middle Pleistocene, the southern limit of the geographic range of extinct representatives of the Brazilian lineage of semifossorial echimyids extended farther south than that of their living members.

Skulls of Echimyidae.
 (1–3) Proclinodontomys dondasi n. gen. n. sp. (MPH-P 0173, holotype) in dorsal (1), ventral (2), and lateral (3) views;
(4–6) P. mordax n. comb. (ZMUC 1/1845:13368) in dorsal (4), ventral (5), and lateral (6) views;
(7–9) E. spinosus (MACN 18103) in dorsal (7), ventral (8), and lateral (9) views.

Abbreviations: bs, basisphenoid; eam, external acoustic meatus; fm, foramen magnum; fr, frontal; I, incisive; if, incisive foramen; iof, infraorbital foramen; ipf, interpremaxillar foramen; ju, jugal; lps, lateral process of supraoccipital; M1, first molar; M2, second molar; M3, third molar; mx, maxilla; na, nasal; oc, occipital; pa, parietal; P4, fourth premolar; pl, palatine; pmx, premaxilla; sq, squamosal; tb, tympanic bulla. Scale bars = 10 mm.

Mandibles of Echimyidae. Left hemimandible of Proclinodontomys dondasi n. gen. n. sp. (MPH-P 0174) in lateral (1) and occlusal (2) views; right hemimandible (reversed) of E. spinosus (MACN 18103) in lateral (3) and occlusal (4) views.

Abbreviations: cp, coronoid process; mc, masseteric crest; m1, first molar; m2, second molar; m3, third molar; mn, masseteric notch; p4, fourth premolar. Scale bars = 10 mm.

Family Echimyidae Gray, 1825 

Subfamily Eumysopinae Rusconi, 1935 

Genus Proclinodontomys new genus 

Type species.—Proclinodontomys dondasi n. gen. n. sp. 

Other species.—Proclinodontomys mordax n. comb. (Winge, 1887).

Etymology.—From Greek pro = anterior, clino = inclination, odonto = tooth, mys = mouse; in reference to the fact that is a rodent with the front teeth inclined forward.

Proclinodontomys dondasi new species

Etymology.—The species name honors Alejandro Dondas (1948–2016), colleague and friend, tireless finder of fossils at the Atlantic cliffs of Buenos Aires Province and for many years head of the Paleontology Department of the Museo Municipal de Ciencias Naturales de Mar del Plata “Lorenzo Scaglia.” The specific epithet is formed from the surname “Dondas,” taken as a noun in the genitive case, plus the Latin suffix “i” (ICZN, 1999; Article 31.1.2).

Proclinodontomys mordax (Winge, 1887) new combination 

1887 Mesomys mordax Winge, p. 72, pl. 8, fig. 7. 

1946 Euryzygomatomys mordax (Winge); Paula-Couto, p. 5.

Adriana M. Candela, Marcos Cenizo, Daniel Tassara, Luciano L. Rasia, Céline Robinet, Nahuel A. Muñoz, Carola Cañón Valenzuela and Ulyses F. J. Pardiñas. 2020. A New Echimyid Genus (Rodentia, Caviomorpha) in Central Argentina: Uncovered Diversity of A Brazilian Group of Mammals in the Pleistocene. Journal of Paleontology. 94(1); 165–179. DOI: 10.1017/jpa.2019.73  

Researchgate.net/publication/336105838_A_new_echimyid_genus_in_Central_Argentina

Hallaron una rata espinosa fósil de más de 400 mil años de antigüedad CTyS.com.ar/index.php?idPage=20&idArticulo=3907

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