Friday, December 19, 2014

[PaleoIchthyology • 2014] Natgeosocus sorini • A New Genus of the Family Palaeocentrotidae (Teleostei, Lampridiformes) from the Oligocene of the northern Caucasus and comments on other fossil Veliferoidei


Natgeosocus sorini Bannikov, 2014

Abstract
A new genus and species of the lampridiform fish Natgeosocus sorini (Palaeocentrotidae) is described based on a single imprint of the skeleton from the Lower Oligocene of the northern Caucasus. To date, the family Palaeocentrotidae has only been known by its monotypic genus from the basal Eocene of Denmark. An overview of fossil records of the suborder Veliferoidei is presented. A separate family is established for the Eocene genus Bajaichthys Sorbini, 1983 from Italy. The diagnosis of the family Palaeocentrotidae is emended.

Keywords: Palaeocentrotidae, Lampridiformes, new taxa, Oligocene, northern Caucasus


A. F. Bannikov. 2014. A New Genus of the Family Palaeocentrotidae (Teleostei, Lampridiformes) from the Oligocene of the northern Caucasus and comments on other fossil Veliferoidei. Paleontological Journal. 48(6); 624-632. DOI: 10.1134/S0031030114060021

Peculiar Extinct Fish With Spines Named for National Geographic
http://on.natgeo.com/1wmvC4q via @NatGeo

Thursday, December 18, 2014

[Herpetology • 2014] Platypelis karenae • A New Phytotelmic Species of Platypelis (Microhylidae: Cophylinae) from the Betampona Reserve, eastern Madagascar


Platypelis karenae
Rosa, Crottini, Noël, Rabibisoa, Raxworthy & Andreone, 2014

  Abstract
We describe a new arboreal and diminutive species of the genus Platypelis from the Réserve Naturelle Intégrale N. 1 de Betampona, one of the last low-altitude rainforest fragments of eastern Madagascar. Platypelis karenae sp. nov. is a phytotelmic species, living among leaves of Pandanus spp. and those of a herbaceous plant of the genus Crinum. Amongst species of comparable size, the new species is most similar to P. tetra, with which it shares a similar life history of occupying leaf axils of phytotelms. Phylogenetically, P. karenae is sister to P. tuberifera yet differentiated by a high level of genetic divergence (>7% p-distance for the analysed fragment of the 16S rRNA gene), its distinctly smaller size, acoustic repertoire, and colour pattern. The mitochondrial, nuclear, bioacoustic, and morphological data all independently support the validity of this new species.

Key words. Amphibia, Anura, new species, miniaturisation, P. karenae sp. n.

Figure 3. Platypelis karenae sp. n. in life:  B) calling male paratype (MRSN A6369) in frontal view inflating its vocal sac; C) Pandanus sp. (another water-retaining plant utilised by P. karenae); D) adult individual of P. karenae sheltering between two leaves of Pandanus sp.; E) juvenile P. karenae in a leaf axil of a Crinum

Gonçalo M. Rosa, Angelica Crottini, Jean Noël, Nirhy Rabibisoa, Christopher J. Raxworthy and Franco Andreone. 2014. A New Phytotelmic Species of Platypelis (Microhylidae: Cophylinae) from the Betampona Reserve, eastern Madagascar. SALAMANDRA. 50(4) 201–214

Tuesday, December 16, 2014

[Ornithology • 2014] Morphological and Behavioral Evidence of Batesian Mimicry in Nestlings of a Lowland Amazonian Bird; Laniocera hypopyrra



Abstract
Because predation is the main cause of avian nest failure, selection should favor strategies that reduce the probability of nest predation. We describe apparent Batesian mimicry in the morphology and behavior of a Laniocera hypopyrra nestling. On hatching, the nestling had a distinctive bright orange color and modified feathers all over its body, and 6 days after hatching, it started to move its head very slowly from side to side (in a “caterpillar” movement) when disturbed. These traits gave it a resemblance to a hairy, aposematic caterpillar. This species has a long nestling period for its size (20 days), perhaps due to slow provisioning rates (about one feeding per hour). We argue that the slow growth rate, combined with high nest predation, favors the evolution of antipredation mechanisms such as the unique morphological and behavioral characteristics of L. hypopyrra nestlings.




Gustavo A. Londoño, Duván A. García and Manuel A. Sánchez Martínez. 2014. Morphological and Behavioral Evidence of Batesian Mimicry in Nestlings of a Lowland Amazonian Bird. The American Naturalist. DOI: 10.1086/679106



Zoologger: The bird that mimics a toxic caterpillar

[Paleontology • 2014] The Danek Edmontosaurus Bonebed: new insights on the Systematics, Biogeography, and Palaeoecology of Late Cretaceous Dinosaur Communities | Le lit d’ossements d’Edmontosaurus de Danek : le point sur la systématique, la biogéographie et la paléoécologie des populations de dinosaures du Crétacé tardif


A large, mature hadrosaurid Edmontosaurus regalis sporting an unusual head crest, surveys an open clearing within a late Cretaceous taxodiaceous conifer forest.
CJES Special Issue 51(11) cdnsciencepub.com Artwork: Michael W. Skrepnick


Introduction: 
“The bonebed was discovered by Danek Mozdzenski, an amateur fossil collector from Edmonton, on March 31, 1989 (Bell and Campione, 2014) and was initially excavated by the Royal Tyrrell Museum of Palaeontology in 1989 and 1991, during which time approximately 80 specimens were collected, including a partial articulated skeleton. The bonebed was reopened by the University of Alberta Laboratory for Vertebrate Palaeontology in 2006, and has since produced over 800 catalogued specimens.”

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The Danek Edmontosaurus Bonebed: new insights on the Systematics, Biogeography, and Palaeoecology of Late Cretaceous Dinosaur Communities. Canadian Journal of Earth Sciences. 51(11) [November 2014] http://www.nrcresearchpress.com/toc/cjes/51/11


 The Danek Edmontosaurus Bonebed: new insights on the systematics, biogeography, and palaeoecology of Late Cretaceous dinosaur communities / Le lit d’ossements d’Edmontosaurus de Danek : le point sur la systématique, la biogéographie et la paléoécologie des populations de dinosaures du Crétacé tardif. Canadian Journal of Earth Sciences, 2014, 51(11): iii, 10.1139/cjes-2014-0148

Michael E. Burns, Clive Coy, Victoria M. Arbour, Philip J. Currie, Eva B. Koppelhus. 2014. The Danek Edmontosaurus Bonebed: new insights on the systematics, biogeography, and palaeoecology of Late Cretaceous dinosaur communities. Canadian Journal of Earth Sciences, 2014, 51(11): v-vii, 10.1139/cjes-2014-0217

David A. Eberth, Phil R. Bell. 2014. Stratigraphy of the Danek Bonebed (Upper Cretaceous Horseshoe Canyon Formation, central Alberta) and correlations with strata in the Drumheller and Grande Prairie regions. Canadian Journal of Earth Sciences, 2014, 51(11): 975-981, 10.1139/cjes-2014-0069

Angelica Torices, Gregory F. Funston, Shannon T. Kraichy, Philip J. Currie. 2014. The first appearance of Troodon in the Upper Cretaceous site of Danek Bonebed, and a reevaluation of troodontid quantitative tooth morphotypes. Canadian Journal of Earth Sciences, 2014, 51(11): 1039-1044, 10.1139/cjes-2014-0071

Phil R. Bell, Philip J. Currie. 2014. Albertosaurus (Dinosauria: Theropoda) material from an Edmontosaurus bonebed (Horseshoe Canyon Formation) near Edmonton: clarification of palaeogeographic distribution. Canadian Journal of Earth Sciences, 2014, 51(11): 1052-1057, 10.1139/cjes-2014-0050

Sunday, December 14, 2014

[Herpetology • 2014] Echinotriton maxiquadratus • A Missing Geographic Link in the Distribution of the Genus Echinotriton (Caudata: Salamandridae) with Description of A New Species from southern China


Echinotriton maxiquadratus Hou, Wu, Yang, Zheng, Yuan & Li, 2014


Abstract

Disjunct geographic distribution of a species or a group of species is the product of long-term interaction between organisms and the environment. Filling the distributional gap by discovery of a new population or a species has significant biogeographic implications, because it suggests a much wider past distribution and provides evidence for the route of range expansion/contraction. The salamandrid genus Echinotriton (commonly known as spiny salamanders, spiny newts, or crocodile newts) has two species that are restricted to two widely separated areas, one in eastern Zhejiang province, China and the other in the Ryukyu Archipelago of Japan. It has been hypothesized that Echinotriton was once continuously distributed between the two areas through a historical land bridge that connected mainland China, Taiwan, and the archipelago. Finding fossils or relic populations along the postulated distribution are strong evidence for the hypothesis. Hundred-twenty-two years after the description of E. andersoni and eight-one years after that of E. chinhaiensis, we discover a third species of Echinotriton in southern China, which fills the distributional gap of the former two species. Species status of the new species is confirmed through molecular phylogenetic analysis and morphological comparison. Mitochondrial DNA indicates that the new species is sister to E. chinhaiensis, while nuclear DNA does not support this relationship. The new species has a very large quadrate projection, a single line of lateral warts pierced by distal rib extremities, normally developed 5th toes, and conical skin tubercles. Our discovery supports the hypothesis that there was a continuous distribution of Echinotriton from eastern coastal China to the Ryukyu Archipelago. We suggest that other species of this genus may also be found in Taiwan. Due to the rarity of this new species, we urge all hobbyists to refrain themselves from collecting this salamander or leaking locality information if encountered, and boycott any trading.

Keywords: Amphibians, salamanders, endangered species, East Asia, molecular phylogenetics, statistical species delimitation




Hou, Mian, Yunke W, Kelin Yang, Sheng Zheng, Zhiyong Yuan & Pipeng Li. 2014. A Missing Geographic Link in the Distribution of the Genus Echinotriton (Caudata: Salamandridae) with Description of A New Species from southern China. Zootaxa. 3895(1): 89–102.

Saturday, December 13, 2014

[Herpetology • 2014] Gekko thakhekensis • A New Species of the Gekko japonicus group (Squamata: Gekkonidae) from central Laos


Gekko thakhekensis
Luu, Calame, Nguyen, Le, Bonkowski & Ziegler, 2014

Abstract
A new species of the Gekko japonicus group is described from Khammouane Province, central Laos, based on distinct morphological and molecular features. Gekko thakhekensis sp. nov. is distinguished from the remaining congeners by a combination of the following characters: size moderate (SVL 67.6–79.2 mm); nares in contact with rostral; internasals absent; postmentals enlarged; interorbital scales between anterior corners of the eyes 22–26; dorsal tubercles absent; ventral scales between mental and cloacal slit 165–174; midbody scale rows 110–116; ventral scale rows 32–40; subdigital lamellae on first toe 11–13, on fourth toe 14–15; finger and toe webbing present at base, about one fifth of length of digits; tubercles on upper surface of fore and hind limbs absent; precloacal pores 1–5 in males; postcloacal tubercles two; tubercles absent on dorsal surface of tail base; subcaudals enlarged; dorsal surface of body with greyish brown blotches. In molecular analyses, the new species is recovered as a sister taxon to G. scientiadventura, but the two species are separated by approximately 12% divergence as shown by the partial mitochondrial ND2 gene.

Keywords: Gekko thakhekensis sp. nov., Khammouane Province, karst forest, morphology, molecular phylogeny


Vinh Quang Luu, Thomas Calame, Truong Quang Nguyen, Minh D. Le, Michael Bonkowski and Thomas Ziegler. 2014. A New Species of the Gekko japonicus group (Squamata: Gekkonidae) from central Laos. Zootaxa. 3895(1):73-88. DOI: 10.11646/zootaxa.3895.1.4

Thursday, December 11, 2014

[Paleontology • 2014] Aquilops americanus • A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America, and the Biogeography of Neoceratopsia


Aquilops americanus Farke, Maxwell, Cifelli & Wedel, 2014
doi: 10.1371/journal.pone.0112055.g006
Life restoration by Brian Engh | DontmesswithDinosaurs.com 

Abstract
The fossil record for neoceratopsian (horned) dinosaurs in the Lower Cretaceous of North America primarily comprises isolated teeth and postcrania of limited taxonomic resolution, hampering previous efforts to reconstruct the early evolution of this group in North America. An associated cranium and lower jaw from the Cloverly Formation (?middle–late Albian, between 104 and 109 million years old) of southern Montana is designated as the holotype for Aquilops americanus gen. et sp. nov.  Aquilops americanus is distinguished by several autapomorphies, including a strongly hooked rostral bone with a midline boss and an elongate and sharply pointed antorbital fossa. The skull in the only known specimen is comparatively small, measuring 84 mm between the tips of the rostral and jugal. The taxon is interpreted as a basal neoceratopsian closely related to Early Cretaceous Asian taxa, such as Liaoceratops and Auroraceratops. Biogeographically, A. americanus probably originated via a dispersal from Asia into North America; the exact route of this dispersal is ambiguous, although a Beringian rather than European route seems more likely in light of the absence of ceratopsians in the Early Cretaceous of Europe. Other amniote clades show similar biogeographic patterns, supporting an intercontinental migratory event between Asia and North America during the late Early Cretaceous. The temporal and geographic distribution of Upper Cretaceous neoceratopsians (leptoceratopsids and ceratopsoids) suggests at least intermittent connections between North America and Asia through the early Late Cretaceous, likely followed by an interval of isolation and finally reconnection during the latest Cretaceous.

Skull and lower jaw of Aquilops
The only known fossil skull of Aquilops puts the dinosaur's small size in perspective; it was about the size of a rabbit.
photo: Andrew A. Farke | blogs.plos.org
Life restoration of Aquilops americanus in right lateral view.
The rendering is based on OMNH 34557 (holotype), with missing details patterned after Liaoceratops yanzigouensis and Archaeoceratops oshimai.
Life restoration by Brian Engh. doi: 10.1371/journal.pone.0112055.g006

Systematic Paleontology

Dinosauria Owen 1842  | Ornithischia Seeley 1887
Ceratopsia Marsh 1890  | Neoceratopsia Sereno 1986

Aquilops gen. nov.
Aquilops americanus sp. nov.

Holotype: OMNH 34557, a partial skull, with associated predentary, partial left dentary, and additional associated but unidentifiable fragments (Figs. 3–9; three-dimensional digital scans are contained in Files S7–S12).

Etymology: The genus name is derived from the Latin aquila, meaning “eagle,” and the Greek ops, meaning “face,” referring to the hooked beak on the skull of the animal. The species name, meaning “American” (Latin), reflects the species' status as the earliest unequivocal neoceratopsian in North America.

Locality and horizon: OMNH locality V1057, 45°N 109°W, Carbon County, Montana, United States of America (Figure 2); basal (?middle–late Albian) part of Unit VII (as defined by [20]), Cloverly Formation. Precise locality data are on file at OMNH and are available to qualified investigators upon request.


Figure 10. Hypothesis of phylogeny and biogeography for Neoceratopsia.
Some terminal taxa have been combined for space considerations, and the range bars for each taxon indicate uncertainty rather than known geological ranges. Continent icons indicate the ancestral areas reconstructed by DEC modeling. Silhouettes depict representative members of major clades and grades (Psittacosaurus by J. Headden, Zuniceratops by N. Tamura and modified by T. M. Keesey; Triceratops by R. Amos; all others by A. Farke; all images are CC-BY and provided via www.phylopic.org). Full results are presented in File S1. doi: 10.1371/journal.pone.0112055.g006


 
Life restoration by Brian Engh | DontmesswithDinosaurs.com


Andrew A. Farke, W. Desmond Maxwell, Richard L. Cifelli and Mathew J. Wedel. 2014. A Ceratopsian Dinosaur from the Lower Cretaceous of Western North America, and the Biogeography of Neoceratopsia. PLoS ONE. DOI: 10.1371/journal.pone.0112055

Aquilops, the little dinosaur that could http://blogs.plos.org/paleo/2014/12/10/aquilops-hello/
Introducing Aquilops americanus http://dontmesswithdinosaurs.com/?p=1220
Bunny-Sized Dinosaur Was First of Its Kind in America http://on.natgeo.com/1x3oyuG via @NatGeo

Wednesday, December 10, 2014

[Herpetology • 2014] Lineage Delimitation and Description of Nine New Species of Bush Frogs (Anura: Raorchestes, Rhacophoridae) from the Western Ghats Escarpment


Raorchestes emeraldi, R. flaviocularis & R. leucolatus 
photos: S. P. Vijayakumar | BBC.com
DOI: 10.11646/zootaxa.3893.4.1

Abstract
Bush frogs of the genus Raorchestes are distributed mainly in the Western Ghats Escarpment of Peninsular India. The inventory of species in this genus is incomplete and there is ambiguity in the systematic status of species recognized by morphological criteria. To address the dual problem of taxon sampling and systematic uncertainty in bush frogs, we used a large-scale spatial sampling design, explicitly incorporating the geographic and ecological heterogeneity of the Western Ghats. We then used a hierarchical multi-criteria approach by combining mitochondrial phylogeny, genetic distance, geographic range, morphology and advertisement call to delimit bush frog lineages. Our analyses revealed the existence of a large number of new lineages with varying levels of genetic divergence. Here, we provide diagnoses and descriptions for nine lineages that exhibit divergence across multiple axes. The discovery of new lineages that exhibit high divergence across wide ranges of elevation and across the major massifs highlights the large gaps in historical sampling. These discoveries underscore the significance of addressing inadequate knowledge of species distribution, namely the “Wallacean shortfall”, in addressing the problem of taxon sampling and unknown diversity in tropical hotspots. A biogeographically informed sampling and analytical approach was critical in detecting and delineating lineages in a consistent manner across the genus. Through increased taxon sampling, we were also able to discern a number of well-supported sub-clades that were either unresolved or absent in earlier phylogenetic reconstructions and identify a number of shallow divergent lineages which require further examination for assessment of their taxonomic status.

Keywords: Species delimitation, Raorchestes, Multi-criteria, Wallacean shortfall, Taxon sampling, Western Ghats


Species accounts: Raorchestes archeos sp. nov., Raorchestes aureus sp. nov., Raorchestes blandus sp. nov., Raorchestes echinatus sp. nov., Raorchestes emeraldi sp. nov., Raorchestes flaviocularis sp. nov., Raorchestes indigo sp. nov., Raorchestes leucolatus sp. nov. and Raorchestes primarrumpfi sp. nov. 


Raorchestes archeos,   Raorchestes blandus,
Raorchestes aureus,   Raorchestes echinatus

photos: S. P. Vijayakumar | DOI: 10.11646/zootaxa.3893.4.1

Raorchestes flaviocularis,   Raorchestes indigo
Raorchestes primarrumpfi  
 | DOI: 10.11646/zootaxa.3893.4.1

Vijayakumar, S. P., K. P. Dinesh, Mrugank V. Prabhu & Kartik Shanker. 2014. Lineage Delimitation and Description of Nine New Species of Bush Frogs (Anura: Raorchestes, Rhacophoridae) from the Western Ghats Escarpment. Zootaxa. 3893(4): 451–488. DOI: 10.11646/zootaxa.3893.4.1

[Paleontology • 2014] Titanochelon • New Generic proposal for the European Neogene Large Testudinids (Cryptodira) and the First Phylogenetic Hypothesis for the medium and large representatives of the European Cenozoic record



Titanochelon bolivari  (Hernández-Pacheco, 1917)
Titanochelon, a new genus of giant tortoise that lived in Europe and western Asia between 20m and 2m years ago. 
Illustration: Mauricio Antón | DOI: 10.1111/zoj.12183

Fossil testudinids are known in Europe since the Eocene, with several taxa of medium size (from more than 0.3 m to less than 0.7 m) recognized in the Palaeogene record, most of them being poorly known. The size of several European Neogene taxa was larger (between 1 and 2 m). These large testudinids were relatively abundant and diverse, ranging from the early Miocene to the Pleistocene. However, there is a nomenclatural gap at the generic level for the Neogene forms, as their generally used assignment to the more primitive Eocene Cheirogaster cannot be sustained. This is because relatively little material has been assigned to the described species, and also because of the absence of a detailed study comparing all of the European taxa. Here, the European Cenozoic taxa are incorporated for the first time in a data matrix, so that a hypothesis on their phylogenetic relationships is justified. This study identified the large testudinids from the Neogene of Europe as belonging to a monophyletic clade, assigned to the new genus Titanochelon. The hitherto poorly understood ‘Testudobolivari, proposed nearly a century ago but lacking diagnosis, is analysed in detail. It is recognized as the best-represented large testudinid from the European record, and is identified as the type species of Titanochelon gen. nov. Its comparison with the other Neogene species allowed a detailed study of the new genus and an analysis of its phylogenetic relationships with the other European taxa.

Keywords: Cheirogaster; Europe; Palaeogene; phylogenetic relationships; Testudinidae; ‘Testudo’ bolivariTitanochelon gen. nov.

giant tortoise Titanochelon bolivari
1) reconstruction by paleoartist Mauricio Antón; 2) - 7) fossil of Titanochelon
| Source: MNCN et culturacientifica

Figure 2. Historical photographs of the shell of the lectotype of Titanochelon bolivari (‘Alcalá 2’), from the MN6 zone (late Aragonian, middle Miocene) of Cerro del Viso, in Alcalá de Henares (Madrid, Spain). Specimen collected in 1917.
A, right lateral view. Modified version of ACN 6553, photograph corresponding to plate XXXIV in Royo y Gómez (1928b). B, left lateral view. Modified version of the unpublished photograph ACN 6554. C, anteroventral view. Modified version of the unpublished photograph ACN 6555. D, dorsoposterior view. Modified version of ACN 6556, photograph corresponding to plate XXXV in Royo y Gómez (1928b).
Original photographs taken by Eduardo Hernández-Pacheco.

SYSTEMATIC PALAEONTOLOGY
CHELONII LATREILLE, 1800
CRYPTODIRA COPE, 1868
TESTUDINOIDEA BATSCH, 1788
TESTUDINIDAE BATSCH, 1788
TESTUDININAE BATSCH, 1788

TITANOCHELON GEN. NOV.
Type species: Titanochelon bolivari (Hernández-Pacheco, 1917a)

Included species: Titanochelon bolivari comb. nov., Titanochelon eurysternum (Gervais, 1848–1852) comb. nov., Titanochelon ginsburgi (de Broin, 1977) comb. nov., Titanochelon vitodurana (Biedermann, 1862) comb. nov., Titanochelon steinbacheri (Karl, 1996) comb. nov., Titanochelon leberonensis (Depéret, 1890) comb. nov., Titanochelon schafferi (Szalai, 1931) comb. nov., Titanochelon perpiniana (Depéret, 1885) comb. nov., Titanochelon bacharidisi (Vlachos et al., 2014) comb. nov. 
Probably included species: cf. Titanochelon gymnesicus (Bate, 1914) comb. nov


Adán Pérez-García and Evangelos Vlachos. 2014. New Generic proposal for the European Neogene Large Testudinids (Cryptodira) and the First Phylogenetic Hypothesis for the medium and large representatives of the European Cenozoic record. Zoological Journal of the Linnean Society. 172, 653–719. DOI: 10.1111/zoj.12183

Tuesday, December 9, 2014

[Ichthyology / Genome • 2014] Mudskipper Genomes provide insights into the Terrestrial Adaptation of Amphibious Fishes


Figure 1: Habitats of the four sequenced mudskippers.  Scartelaos histophorus (SH or blue mudskipper), Boleophthalmus pectinirostris (BP or blue-spotted mudskipper), Periophthalmodon schlosseri (PS or giant mudskipper) and Periophthalmus magnuspinnatus (PM or giant-fin mudskipper)


Mudskippers are amphibious fishes that have developed morphological and physiological adaptations to match their unique lifestyles. Here we perform whole-genome sequencing of four representative mudskippers to elucidate the molecular mechanisms underlying these adaptations. We discover an expansion of innate immune system genes in the mudskippers that may provide defence against terrestrial pathogens. Several genes of the ammonia excretion pathway in the gills have experienced positive selection, suggesting their important roles in mudskippers’ tolerance to environmental ammonia. Some vision-related genes are differentially lost or mutated, illustrating genomic changes associated with aerial vision. Transcriptomic analyses of mudskippers exposed to air highlight regulatory pathways that are up- or down-regulated in response to hypoxia. The present study provides a valuable resource for understanding the molecular mechanisms underlying water-to-land transition of vertebrates.

......


Xinxin You, Chao Bian, Qijie Zan, Xun Xu, Xin Liu, Jieming Chen, Jintu Wang, Ying Qiu, Wujiao Li, Xinhui Zhang, Ying Sun, Shixi Chen, Wanshu Hong, Yuxiang Li, Shifeng Cheng, Guangyi Fan, Chengcheng Shi, Jie Liang, Y. Tom Tang, Chengye Yang, Zhiqiang Ruan, Jie Bai, Chao Peng, Qian Mu, Jun Lu, Mingjun Fan, Shuang Yang, Zhiyong Huang, Xuanting Jiang, Xiaodong Fang, Guojie Zhang, Yong Zhang, Gianluca Polgar, Hui Yu, Jia Li, Zhongjian Liu, Guoqiang Zhang, Vydianathan Ravi, Steven L. Coon, Jian Wang, Huanming Yang, Byrappa Venkatesh, Jun Wang & Qiong Shi. 2014. Mudskipper Genomes provide insights into the Terrestrial Adaptation of Amphibious Fishes. Nature Communications 5, Article number: 5594 doi: 10.1038/ncomms6594

Saturday, December 6, 2014

[Paleontology • 2014] New Specimen of Archaeopteryx provides Insights into The Evolution of Pennaceous Feathers | The Flight for First Bird


Archaeopteryx’s status is changing, but the animal is still key to the dinosaur–bird transition.
Illustration by Emily Willoughby; Graphics: Jasiek Krzysztofiak/Nature;
doi: 10.1038/nature13467 10.1038/516018a

The iconic status of Archaeopteryx, the first animal discovered with both bird and dinosaur features, is under attack. More-recently discovered rival species show a similar mix of traits. But Archaeopteryx still hogged the opening symposium at the 2014 Society of Vertebrate Paleontology meeting in Berlin last month, and even festooned the official conference beer glasses.

As the simplistic idea of a ‘first’ bird gives way to a messy evolutionary transition, newly discovered fossils and improved analysis techniques put Archaeopteryx in prime position to unravel the details. “Research on Archaeopteryx is really catching a new breath,” says palaeobiologist Martin Kundrat of Uppsala University in Sweden, who co-organized the symposium at the November meeting.

The first Archaeopteryx fossil specimens turned up in limestone quarries in Bavaria, southern Germany, in the early 1860s. Until recently, they were the only fossil specimens found to mix bird- and dinosaur-like features. On the one hand, they are small — the fossils show juvenile creatures about the size of a magpie, which as adults may have been raven-sized — and have broad feathered wings that look good for gliding; on the other, they have a jaw with sharp teeth, dinosaur-like claws and a bony tail. These features led to the idea of the first bird, and generations of scientists have treated the 145-million-year-old animal as a ‘transitional species’ — the key piece of evidence linking birds and dinosaurs (Archaeopteryx is Greek for ‘ancient feather’, whereas its German name, ‘Urvogel’, means ‘first bird’).

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Discoveries of bird-like theropod dinosaurs and basal avialans in recent decades have helped to put the iconic ‘Urvogel’ Archaeopteryx into context and have yielded important new data on the origin and early evolution of feathers. However, the biological context under which pennaceous feathers evolved is still debated. Here we describe a new specimen of Archaeopteryx with extensive feather preservation, not only on the wings and tail, but also on the body and legs. The new specimen shows that the entire body was covered in pennaceous feathers, and that the hindlimbs had long, symmetrical feathers along the tibiotarsus but short feathers on the tarsometatarsus. Furthermore, the wing plumage demonstrates that several recent interpretations are problematic. An analysis of the phylogenetic distribution of pennaceous feathers on the tail, hindlimb and arms of advanced maniraptorans and basal avialans strongly indicates that these structures evolved in a functional context other than flight, most probably in relation to display, as suggested by some previous studies. Pennaceous feathers thus represented an exaptation and were later, in several lineages and following different patterns, recruited for aerodynamic functions. This indicates that the origin of flight in avialans was more complex than previously thought and might have involved several convergent achievements of aerial abilities.

Christian Foth, Helmut Tischlinger and Oliver W. M. Rauhut. 2014. New Specimen of Archaeopteryx provides Insights into The Evolution of Pennaceous Feathers. Nature. 511, 79–82. doi: 10.1038/nature13467


Amy M. Balanoff, Gabe S. Bever, Timothy B. Rowe and Mark A. Norell. 2013. Evolutionary origins of the avian brain. Nature. 501, 93–96 doi: dx.doi.org/10.1038/nature12424
Ryan M. Carney, Jakob Vinther, Matthew D. Shawkey, Liliana D'Alba and Jörg Ackermann. 2012. New evidence on the colour and nature of the isolated Archaeopteryx feather. Nature Communications. 3, Article number: 637 doi: 10.1038/ncomms1642

Ewen Callaway. 2014. Rival Species recast significance of ‘First Bird’. Nature516, 18–19 (04 December 2014) doi: 10.1038/516018a

[Ichthyology • 2014] Cynopoecilus notalebis • Description of A New Species and Phylogenetic Analysis of the Subtribe Cynopoecilina, including Continuous Characters without Discretization (Cyprinodontiformes: Rivulidae)


 Cynopoecilus notalebis
 Ferrer, , Wingert  & Malabarba, 2014

A new species of the subtribe Cynopoecilina is described from the rio Gravataí basin, laguna dos Patos system, southern Brazil. The relationships of the new species among taxa of the subtribe Cynopoecilina is discussed based on two analyses: one using 71 discrete characters and other with the addition of six continuous characters analyzed without discretization. The addition of the continuous characters resulted in the first fully resolved phylogenies for Cynopoecilus and Leptolebias species, not obtained in the analysis including only discrete characters. The new species is assigned to Cynopoecilus as sister group to the remaining species of the genus. A new diagnosis is proposed for Cynopoecilus to accommodate the new species. The resulting phylogeny indicates that the occupation of the grasslands of the Pampa biome by the species of Cynopoecilus occurred along the evolution of the genus and that this event was significant for the diversification of the genus.


Keywords: Aplocheiloidei; Campellolebias; conservation; Cynopoecilus; killifishes; Leptolebias; neotropical; Notholebias




 Ferrer, J., Wingert, J.M. & Malabarba, L.R. 2014. Description of A New Species and Phylogenetic Analysis of the Subtribe Cynopoecilina, including Continuous Characters without Discretization (Cyprinodontiformes: Rivulidae). Zoological Journal of the Linnean Society. 172(4); 846–866. DOI: 10.1111/zoj.12190