[Mammalogy • 2023] An evolutionarily distinct Ringed Seal in the Ilulissat Icefjord, Greenland

Kangia ringed seals Pusa hispida hispida in the Ilulissat Icefjord system, West Greenland 

(c) Pelage of Kangia (left) and typical Arctic ringed seals (right).

in Rosing-Asvid, Löytynoja, Momigliano, Hansen, ... et Olsen, 2023.

DOI: 10.1111/mec.17163

 All photographs by Greenland Institute of Natural Resources.

 

Abstract

The Earth's polar regions are low rates of inter- and intraspecific diversification. An extreme mammalian example is the Arctic ringed seal (Pusa hispida hispida), which is assumed to be panmictic across its circumpolar Arctic range. Yet, local Inuit communities in Greenland and Canada recognize several regional variants; a finding supported by scientific studies of body size variation. It is however unclear whether this phenotypic variation reflects plasticity, morphs or distinct ecotypes. Here, we combine genomic, biologging and survey data, to document the existence of a unique ringed seal ecotype in the Ilulissat Icefjord (locally ‘Kangia’), Greenland; a UNESCO World Heritage site, which is home to the most productive marine-terminating glacier in the Arctic. Genomic analyses reveal a divergence of Kangia ringed seals from other Arctic ringed seals about 240 kya, followed by secondary contact since the Last Glacial Maximum. Despite ongoing gene flow, multiple genomic regions appear under strong selection in Kangia ringed seals, including candidate genes associated with pelage coloration, growth and osmoregulation, potentially explaining the Kangia seal's phenotypic and behavioural uniqueness. The description of ‘hidden’ diversity and adaptations in yet another Arctic species merits a reassessment of the evolutionary processes that have shaped Arctic diversity and the traditional view of this region as an evolutionary freezer. Our study highlights the value of indigenous knowledge in guiding science and calls for efforts to identify distinct populations or ecotypes to understand how these might respond differently to environmental change.

Keywords: arctic, diversity, indigenous knowledge, local adaptation, marine mammal

Unusual population of ringed seals in the Ilulissat Icefjord system, West Greenland.
 (a) Kangia ringed seals hauling out on sea ice.
(b) The dynamic Ilulissat Icefjord system. (c) Pelage of Kangia (left) and typical Arctic ringed seals (right).
 (d) Kangia ringed seal instrumented with a satellite tag (image edited to remove person in background. Original image provided in (d). (e) Typical Arctic ringed seal instrumented with a satellite tag (movement data not shown).

 All photographs by Greenland Institute of Natural Resources.

CONCLUSION: 

The discovery of a distinct ringed seal ecotype in the Ilulissat Icefjord adds to a growing list of Arctic marine species with newly detected genetic and/or phenotypic diversity (Bringloe et al., 2020; Jacobsen et al., 2022; Laidre et al., 2022; Madsen et al., 2016; Mathiesen et al., 2017; Tempestini et al., 2020). The Arctic environment is highly dynamic, with marine systems characterized by long- and short-term fluctuations in glacial extent and run-off, marine-freshwater clines, sea-level changes and isostatic rebound. These processes might facilitate both regional and local speciation, perhaps down to the scale of individual fjord systems or larger marine-terminating glacier fronts. Thus, while our study is the first to demonstrate the existence of a distinct Kangia ringed seal ecotype in the Ilulissat Icefjord, similar intraspecific diversity and differentiation may exist elsewhere in both ringed seals and other Arctic marine species. Across the Arctic, marine-terminating glaciers, deep fjord systems and polynyas sustain high biological productivity and provide important foraging and resting habitats for marine organisms (Heide-Jørgensen et al., 2016; Lydersen et al., 2014; Meire et al., 2017). These areas may have constituted important high-latitude refugia and even micro-evolutionary speciation factories through glacial and interglacial periods, potentially supporting uniquely adapted populations of otherwise wide-spread and seemingly panmictic Arctic marine organisms. Some local populations may not easily respond to climate change by simply tracking their habitat northward, whereas others may harbour the adaptive potential providing species-level resistance to current climate warming. Our findings highlight the need for dedicated scientific efforts and thorough sampling to record and understand regional and local drivers of intraspecific diversity in the Arctic to provide information for nature management.

Aqqalu Rosing-Asvid, Ari Löytynoja, Paolo Momigliano, Rikke Guldborg Hansen, Camilla Hjorth Scharff-Olsen, Mia Valtonen, Juhana Kammonen, Rune Dietz, Frank Farsø Rigét, Steve H. Ferguson, Christian Lydersen, Kit M. Kovacs, David M. Holland, Jukka Jernvall, Petri Auvinen and Morten Tange Olsen. 2023. An evolutionarily distinct Ringed Seal in the Ilulissat Icefjord. Molecular Ecology. DOI: 10.1111/mec.17163

  phys.org/news/2023-10-west-greenland.html

[Paleontology • 2022] Qikiqtania wakei • A New Elpistostegalian (Sarcopterygii: Tetrapodomorpha) from the Late Devonian of the Canadian Arctic

Qikiqtania wakei

 Stewart, Lemberg, Daly, Daeschler & Shubin, 2022

DOI: 10.1038/s41586-022-04990-w

Abstract

A fundamental gap in the study of the origin of limbed vertebrates lies in understanding the morphological and functional diversity of their closest relatives. Whereas analyses of the elpistostegalians Panderichthys rhombolepis, Tiktaalik roseae and Elpistostege watsoni have revealed a sequence of changes in locomotor, feeding and respiratory structures during the transition, an isolated bone, a putative humerus, has controversially hinted at a wider range in form and function than now recognized. Here we report the discovery of a new elpistostegalian from the Late Devonian period of the Canadian Arctic that shows surprising disparity in the group. The specimen includes partial upper and lower jaws, pharyngeal elements, a pectoral fin and scalation. This new genus is phylogenetically proximate to T. roseae and E. watsoni but evinces notable differences from both taxa and, indeed, other described tetrapodomorphs. Lacking processes, joint orientations and muscle scars indicative of appendage-based support on a hard substrate, its pectoral fin shows specializations for swimming that are unlike those known from other sarcopterygians. This unexpected morphological and functional diversity represents a previously hidden ecological expansion, a secondary return to open water, near the origin of limbed vertebrates.

Systematic palaeontology

Sarcopterygii Romer, 1955

Tetrapodomorpha Ahlberg, 1991

Elpistostegalia Camp and Allison, 1961

Qikiqtania wakei gen. et sp. nov.

Locality. Canada, Nunavut, southern Ellesmere Island, near the eastern arm of Bird Fiord, Nunavut Paleontological Expedition site NV0401, ....

Geological setting. Fram Formation (Upper Devonian, early Frasnian Stage).

Holotype. Nunavut Fossil Vertebrate Collection (NUFV) 137.

 

Diagnosis. Elpistostegalian tetrapodomorph characterized by the following unique combination of characters: dorsoventral asymmetry in pectoral fin lepidotrichia (also present in T. roseae) and possession of a boomerang-shaped humerus lacking ventral ridge and associated foramina and ectepicondyle (distinct from P. rhombolepis, E. watsoni, T. roseae and more crownward tetrapods).

Etymology. Qikiqtania (pronounced ‘kick-kiq-tani-ahh’) is derived from Inuktitut word Qikiqtaaluk/Qikiqtani, the traditional name for the region where the fossil site occurs. The species designation is in memory of David Wake, an eminent evolutionary biologist and transformative mentor, late of the University of California at Berkeley.

 

Thomas A. Stewart, Justin B. Lemberg, Ailis Daly, Edward B. Daeschler and Neil H. Shubin. 2022. A New Elpistostegalian from the Late Devonian of the Canadian Arctic. Nature. DOI: 10.1038/s41586-022-04990-w

    

[Paleontology • 2022] Cretaceous Dinosaurs across Alaska Show the Role of Paleoclimate in Structuring Ancient Large-Herbivore Populations

Examples of vertebrate fossil data used in this study.
(1) Prince Creek Formation, North Slope, C1, bonebed.
(2) lower Cantwell Formation, Denali National Park, C2, ceratopsian footprint.
(3) Chignik Formation, Aniakchak National Monument, C3 hadrosaur footprint.

in Fiorillo, McCarthy, Kobayashi & Suarez, 2022.

DOI: 10.3390/geosciences12040161 

 twitter.com/dgdt2425 

Abstract

The partially correlative Alaskan dinosaur-bearing Prince Creek Formation (PCF), North Slope, lower Cantwell Formation (LCF), Denali National Park, and Chignik Formation (CF), Aniakchak National Monument, form an N–S transect that, together, provides an unparalleled opportunity to examine an ancient high-latitude terrestrial ecosystem. The PCF, 75–85° N paleolatitude, had a Mean Annual Temperature (MAT) of ~5–7 °C and a Mean Annual Precipitation (MAP) of ~1250 mm/year. The LCF, ~71° N paleolatitude, had a MAT of ~7.4 °C and MAP of ~661 mm/year. The CF, ~57° N paleolatitude, had a MAT of ~13 °C and MAP of ~1090 mm/year. The relative abundances of the large-bodied herbivorous dinosaurs, hadrosaurids and ceratopsids, vary along this transect, suggesting that these climatic differences (temperature and precipitation) played a role in the ecology of these large-bodied herbivores of the ancient north. MAP played a more direct role in their distribution than MAT, and the seasonal temperature range may have played a secondary role.

Keywords: hadrosaurs; ceratopsians; Arctic; ancient Arctic; terrestrial ecosystems; ecosystem reconstruction

Figure 1. Maps showing general locations of study areas. (A) Modern Alaska. (B) Polar projection of tectonic plates during the Late Cretaceous (Base map from PLATES Project, University of Texas Institute of Geophysics). The inner latitudinal ring on map represents 45° N.
 (C) Examples of vertebrate fossil data used in this study. (1) Prince Creek Formation, North Slope, C1, bonebed. (2) lower Cantwell Formation, Denali National Park, C2, ceratopsian footprint, Denali National Park. (3) Chignik Formation, Aniakchak National Monument, C3 hadrosaur footprint.

Examples of vertebrate fossil data used in this study. (1) Prince Creek Formation, North Slope, C1, bonebed. (2) lower Cantwell Formation, Denali National Park, C2, ceratopsian footprint, Denali National Park. (3) Chignik Formation, Aniakchak National Monument, C3 hadrosaur footprint.

 

   

 Anthony R. Fiorillo, Paul J. McCarthy, Yoshitsugu Kobayashi and Marina B. Suarez. 2022. Cretaceous Dinosaurs across Alaska Show the Role of Paleoclimate in Structuring Ancient Large-Herbivore Populations. Geosciences. 12(4)  (Special Issue: Terrestrial Paleoclimatology and Paleohydrology of the Cretaceous Greenhouse World); 161. DOI: 10.3390/geosciences12040161

  twitter.com/dgdt2425/status/1519512980265652224

Cover Story: The impacts of a changing climate are of major societal concern with great interest on mitigation or modeling how a future, warmer world would look. It is also broadly recognized that the impacts of a warming Earth are most profoundly expressed in the polar regions. Climate change encompasses many components. Our new study reviews the ample evidence for a flourishing ancient Arctic terrestrial ecosystem during the Late Cretaceous greenhouse mode in Earth history, an ecosystem where the local paleoclimate was a primary driver in structuring the relative abundances of large-bodied herbivores in local environments. Further, analysis suggests that mean annual precipitation (MAP) played a more direct role in determining the distribution of herbivorous dinosaurs than mean annual temperature (MAT) did. 

[Paleontology • 2021] Auroroborealia incognita • Ichthyosaurs from the Upper Triassic (Carnian–Norian) of the New Siberian Islands, Russian Arctic, and Their Implications for the Evolution of the Ichthyosaurian Basicranium and Vertebral Column

Auroroborealia incognita

Zverkov, Grigoriev, Wolniewicz, Konstantinov & Sobolev, 2021

DOI: 10.1017/S1755691021000372 

 twitter.com/ASWolniewicz

Abstract

The first ichthyosaurian specimens discovered from the Upper Triassic of the Russian Arctic (Kotelny Island, New Siberian Islands) are described herein. They include the remains of large- to small-bodied ichthyosaurians originating from six stratigraphic levels spanning the lower Carnian to middle Norian. The material is mostly represented by isolated vertebrae and ribs, which are not possible to accurately diagnose, but also includes specimens comprising associated vertebrae and a fragmentary skeleton that preserves cranial remains (parabasisphenoid, fragmentary quadrate, partial mandible and hyoids). Based on vertebral and rib morphology, we identify the specimens as representatives of the following taxonomic groups: large-bodied shastasaurids, medium-sized indeterminate ichthyosaurians with a single rib facet in the presacral centra, and small euichthyosaurians with double rib facets present throughout the presacral vertebrae that likely represent toretocnemids and/or basal parvipelvians. In addition, the cranial and mandibular remains preserved in one of the specimens, ZIN PH 5/250, were studied using micro-computed tomography. Its mandible is highly similar to that of toretocnemids, whereas the parabasisphenoid demonstrates a peculiar combination of both plesiomorphic and derived character states, providing the first detailed data on this cranial element in a Late Triassic ichthyosaurian. Furthermore, the specimen also demonstrates a distinctive condition of rib articulation in the anteriormost presacral (cervical) vertebrae, which together with other features allows for the erection of a new taxon – Auroroborealia incognita gen. et sp. nov. Although the phylogenetic position of this taxon is uncertain due to its fragmentary nature, its anatomy, indicating toretocnemid or parvipelvian affinities, further supports the previously hypothesised sister-group relationships between these two clades. The morphology of the parabasisphenoid and vertebral column of the new taxon is discussed in broader contexts of the patterns of evolution of these skeletal regions in ichthyosaurs.

Keywords: Euichthyosauria, Ichthyosauria, Late Triassic, Norian, parabasisphenoid, Parvipelvia, Toretocnemidae

Nikolay G. Zverkov, Dmitry V. Grigoriev, Andrzej S. Wolniewicz, Alexey G. Konstantinov and Evgeny S. Sobolev. 2021. Ichthyosaurs from the Upper Triassic (Carnian–Norian) of the New Siberian Islands, Russian Arctic, and Their Implications for the Evolution of the Ichthyosaurian Basicranium and Vertebral Column. Earth and Environmental Science Transactions of The Royal Society of Edinburgh.  First View. DOI: 10.1017/S1755691021000372

  twitter.com/ASWolniewicz/status/1470398055866200068

[PaleoMammalogy • 2020] Lifetime Mobility of An Arctic Woolly Mammoth Mammuthus primigenius

An adult male woolly mammoth Mammuthus primigenius navigating a mountain pass in Arctic Alaska. Little is known about the movement patterns of these extinct giants.
Isotopic records from a 17,100-year-old mammoth tusk reveal that the animal covered an extensive geographic range during its lifetime. However, as the ice age ended and the Arctic environment began to change, maintaining this level of mobility would have been increasingly difficult.

in Wooller, Bataille, Druckenmiller, ... et Willis, 2021. 

DOI: 10.1126/science.abg1134

Illustration: James Havens/The Havens Studio, Alaska

 facebook.com: James Havens 

A mammoth's life: 

Fossils have long given us glimpses of the life that came before us, but these glimpses are generally static. They tell us a bit about species that lived, but not much about how they lived. Evolving techniques are deepening our viewpoint. Wooller et al. examined isotopes collected from the tusk of a 17,000-year-old mammoth to elucidate its movements from birth to death. This included its time—likely with a herd—as an infant and juvenile, then as a prime-age adult, and then as a declining senior over its approximately 28-year life span.

Abstract

Little is known about woolly mammoth (Mammuthus primigenius) mobility and range. Here we use high temporal resolution sequential analyses of strontium isotope ratios along an entire 1.7-meter-long tusk to reconstruct the movements of an Arctic woolly mammoth that lived 17,100 years ago, during the last ice age. We use an isotope-guided random walk approach to compare the tusk’s strontium and oxygen isotope profiles to isotopic maps. Our modeling reveals patterns of movement across a geographically extensive range during the animal’s ~28-year life span that varied with life stages. Maintenance of this level of mobility by megafaunal species such as mammoth would have been increasingly difficult as the ice age ended and the environment changed at high latitudes.

Reproduction of a life-size oil painting of an adult male woolly mammoth Mammuthus primigenius navigating a mountain pass in Arctic Alaska. Little is known about the movement patterns of these extinct giants. Isotopic records from a 17,100-year-old mammoth tusk reveal that the animal covered an extensive geographic range during its lifetime. However, as the ice age ended and the Arctic environment began to change, maintaining this level of mobility would have been increasingly difficult.

DOI: 10.1126/science.abg1134

Illustration: James Havens/The Havens Studio, Alaska

 facebook.com/JamesHavens585 

Matthew J. Wooller, Clement Bataille, Patrick Druckenmiller, Gregory M. Erickson, Pamela Groves, Norma Haubenstock, Timothy Howe, Johanna Irrgeher, Daniel Mann, Katherine Moon, Ben A. Potter, Thomas Prohaska, Jeffrey Rasic, Joshua Reuther, Beth Shapiro, Karen J. Spaleta and Amy D. Willis. 2021. Lifetime Mobility of An Arctic Woolly Mammoth. Science. 373, 6556; 806-808. DOI: 10.1126/science.abg1134

 facebook.com/JamesHavens585/posts/3717061821853267

[Paleontology • 2021] Nesting at Extreme Polar Latitudes by Non-avian Dinosaurs

Nanuqsaurus hoglundi with its young.

in Druckenmiller, Erickson, ... et Eberle, 2021. 

 DOI: 10.1016/j.cub.2021.05.041

Illustration: James Havens

 

Highlights

• Perinatal dinosaurs reported from the Late Cretaceous of northern Alaska

• A diverse assemblage of dinosaur species reproduced in the Arctic

• Large- and small-bodied taxa were nonmigratory year-round residents

• Paleoenvironmental constraints suggest polar-specific life history strategies

Summary

The unexpected discovery of non-avian dinosaurs from Arctic and Antarctic settings has generated considerable debate about whether they had the capacity to reproduce at high latitudes—especially the larger-bodied, hypothetically migratory taxa. Evidence for dinosaurian polar reproduction remains very rare, particularly for species that lived at the highest paleolatitudes (>75°). Here we report the discovery of perinatal and very young dinosaurs from the highest known paleolatitude for the clade—the Cretaceous Prince Creek Formation (PCF) of northern Alaska. These data demonstrate Arctic reproduction in a diverse assemblage of large- and small-bodied ornithischian and theropod species. In terms of overall diversity, 70% of the known dinosaurian families, as well as avialans (birds), in the PCF are represented by perinatal individuals, the highest percentage for any North American Cretaceous formation. These findings, coupled with prolonged incubation periods, small neonate sizes, and short reproductive windows suggest most, if not all, PCF dinosaurs were nonmigratory year-round Arctic residents. Notably, we reconstruct an annual chronology of reproductive events for the ornithischian dinosaurs using refined paleoenvironmental/plant phenology data and new insights into dinosaur incubation periods. Seasonal resource limitations due to extended periods of winter darkness and freezing temperatures placed severe constraints on dinosaurian reproduction, development, and maintenance, suggesting these taxa showed polar-specific life history strategies, including endothermy.

 

Keywords: Arctic, reproduction, Dinosauria, Alaska, Prince Creek Formation, Cretaceous, perinate, migration, incubation

the tyrannosaur Nanuqsaurus hoglundi with its young.

Illustration: James Havens

 Patrick S. Druckenmiller, Gregory M. Erickson, Donald Brinkman, Caleb M. Brown and Jaelyn J. Eberle. 2021. Nesting at Extreme Polar Latitudes by Non-avian Dinosaurs. Current Biology. In Press. DOI: 10.1016/j.cub.2021.05.041

Multiple dinosaur species not only lived in the Arctic, they also nested there

 eurekalert.org/pub_releases/2021-06/cp-mds061721.php

phys.org/news/2021-06-multiple-dinosaur-species-arctic.html

[PaleoMammalogy • 2021] Dietary Reconstruction and Evidence of Prey Shifting in Pleistocene and Recent Gray Wolves (Canis lupus) from Yukon Territory

Gray Wolves Canis lupus from Pleistocene Yukon Territory

in Landry, Kim, Trayler, ... et Fraser, 2021.

DOI: 10.1016/j.palaeo.2021.110368 

Illustration: Julius Csotonyi  facebook.com/JuliusCsotonyi 

 

Highlights

• Stable isotopes and dental microwear reveal diets of ancient and modern gray wolves.

• Yukon gray wolves remained large ungulate specialists from Pleistocene to present.

• Yukon gray wolves have remained primarily flesh-consumers.

• Yukon gray wolves transitioned from diets mostly composed of horse to cervids.

• Conservation efforts in the Yukon should focus on ungulate populations.

Abstract

We investigate if and how diets of gray wolves from the Yukon Territory, Canada, have changed from the Pleistocene (>52.8 ka BP to 26.5 ka BP [±170 y BP]) to the recent Holocene (1960s) using dental microwear analysis of carnassial teeth and stable isotope analyses of carbonates (δ13CCO3 and δ18OCO3) and collagen (δ13Ccol and δ15Ncol) from bone. We find that dental microwear patterns are similar between the Pleistocene and Holocene specimens, indicating that there has been no change in carcass utilization behaviours, where flesh, not bone, is primarily consumed. Based on minimal changes in δ13CCO3 and δ13Ccol values, we find that, over thousands of years, Yukon gray wolves have remained generalist predators feeding upon several large ungulate species. Interestingly, δ15Ncol values suggest that the extinction of megafaunal species at ~11.7 Ka induced a shift from a diet comprised primarily of horse (Equus sp.) to one based on cervids (i.e. moose and caribou). Survival of large-bodied cervids, such as caribou (Rangifer tarandus), was likely key to wolf survival. Although gray wolves survived the end Pleistocene megafauna extinction and demonstrate a degree of ecological flexibility, we suggest that failure to preserve major elements of their current niche (e.G. caribou) may result in continued population declines, especially in the face of increasing anthropogenic influences.

 Keywords: Gray wolf, Dietary ecology, Stable isotopes, Dental microwear, Pleistocene

 

 Zoe Landry, Sora Kim, Robin B. Trayler, Marisa,Gilbert, Grant Zazula, John Southon and Danielle Fraser. 2021. Dietary Reconstruction and Evidence of Prey Shifting in Pleistocene and Recent Gray Wolves (Canis lupus) from Yukon Territory. Palaeogeography, Palaeoclimatology, Palaeoecology. 571, 110368. DOI: 10.1016/j.palaeo.2021.110368  

... a fascinating new paper on how wolves survived the biological bottleneck of the Pleistocene megafaunal extinctions in Beringian North America by switching their diet from horses to caribou and moose. It was a privilege to work with these scientists through the Yukon Beringia Interpretive Centre to produce a new piece of paleoart to visually support this paper, featuring a pack of Beringian wolves hunting soon-to-be-extirpated horses in the pre-extinction heyday of the huge mammoth steppe environment.

 facebook.com/JuliusCsotonyi/posts/10157607329656396

nature.ca/en/about-us/museum-news/news/press-releases/new-study-shows-shift-diet-allowed-gray-wolves-survive-ice

[Mammalogy • 2021] Lemmus lemmus chernovi • A New Norwegian Lemming Subspecies (Rodentia: Cricetidae) from Novaya Zemlya, Arctic Russia

Lemmus lemmus chernovi Spitsyn, Bolotov & Kondakov 

in Spitsyn, Bolotov, Kondakov, ... et Gofarov, 2021.

DOI: 10.37828/em.2021.40.8 

 twitter.com/EMontenegrina 

Abstract

Norwegian Lemming Lemmus lemmus is a remarkable population cycling species having a number of aposematic traits in coloration and behavior. This species was thought to be the only mammal endemic to Fennoscandia. Here, we report on the discovery of a distinct lineage of this species from Novaya Zemlya. This lineage is described here as the new subspecies Lemmus lemmus chernovi ssp. nov. that morphologically differs from the nominate subspecies by having a cryptic coloration. Our time-calibrated phylogeny revealed that this insular subspecies was isolated there since the Eemian interglacial (mean age 93 Ka). Hence, bright coloration and antipredator behavior of the nominate subspecies are novel aposematic traits that evolved since its isolation in a European refugium. This new discovery indicates that Novaya Zemlya supported a cryptic polar refugium for cold-adapted terrestrial fauna during the Pleistocene. Finally, our findings highlight that allopatric ranges of the true lemmings (Lemmus) reflect stepwise range expansions in cold climatic episodes with subsequent isolation in refugia during interglacial events.

Key words: Arctic Ocean islands, cryptic polar refugium, Eemian interglacial, integrative taxonomy, Lemmus lemmus, Lemmini, phylogeography, Pleistocene glaciations

Dorsal view of lemming specimens:
(A) Novaya Zemlya Lemming (Lemmus lemmus chernovi ssp. nov.) [holotype RMBH Lem005], and
(B) Norwegian Lemming (L. lemmus lemmus) [RMBH Lem040, Kola Peninsula].

Scale bar = 10 mm. (Photos: Vitaly M. Spitsyn).

Lemmus lemmus chernovi Spitsyn, Bolotov & Kondakov ssp. nov. 

Common name: Novaya Zemlya Lemming

Differential diagnosis: The Novaya Zemlya Lemming differs from the nominate subspecies by having a cryptic coloration of dorsal surface that is dark gray with yellow and reddish hairs in adults (Fig. 6A) to reddish in juveniles, with an unclear longitudinal black stripe in anterior part from neck to nose (vs bright yellow coloration with black anterior part of the trunk and large black spots on head). The new subspecies is morphologically similar to Lemmus sibiricus but adult specimens from Novaya Zemlya could be distinguished from it by dorsal coloration with yellow and reddish hairs (vs brown and reddish hairs).

Etymology: This subspecies is named in memory of the late Academician of the Russian Academy of Sciences Yury I. Chernov (1934-2012), a prominent Russian zoologist, biogeographer, and Arctic explorer. 

Distribution and habitat: This subspecies is endemic to the Southern Island of Novaya Zemlya, while its reliable records from the Northern Island of this archipelago are unknown (Fig. 1A). It inhabits a broad range of meadow-like (Fig. 1B) and tundra habitats

Figure 5. Ancestral coloration reconstruction (Bayesian Binary MCMC analysis) of Lemmus taxa based on our fossilcalibrated BEAST v. 1.10.4 phylogeny. Black numbers near nodes are BEAST’s BPP. The Lemmus trimucronatus + L. nigripes clade (cryptic coloration) is omitted. (Photos: Vitaly M. Spitsyn).

 

Vitaly M. Spitsyn, Ivan N. Bolotov, Alexander V. Kondakov, Anna L. Klass, Ivan A. Mizin, Alena A. Tomilova, Natalia A. Zubrii and Mikhail Y. Gofarov. 2021. A New Norwegian Lemming Subspecies from Novaya Zemlya, Arctic Russia. Ecologica Montenegrina. 40; In Progress. 93-117. DOI: 10.37828/em.2021.40.8

  twitter.com/EMontenegrina/status/1371916875446284292

[Paleontology • 2020] Jucha squalea • A New Elasmosaurid Plesiosaurian from the Early Cretaceous of Russia marks An early Attempt at Neck Elongation

Jucha squalea 

Fischer, Zverkov, Arkhangelsky, Stenshin, Blagovetshensky & Uspensky, 2020

DOI: 10.1093/zoolinnean/zlaa103 

 twitter.com/Val_Fisch 

Illustration: Andrey Atuchin 

 

Abstract

Plesiosaurian marine reptiles evolved a wide range of body shapes during the Jurassic and Cretaceous, including long-necked forms. Many Late Cretaceous members of the clade Elasmosauridae epitomized this part of the plesiosaurian morphological spectrum by evolving extremely long necks through somitogenesis (resulting in an increase in the number of cervical centra) and differential growth (resulting in the elongation of cervical centra). However, the early evolution of elasmosaurids remains poorly understood because of a generally poor Lower Cretaceous fossil record. We describe a new elasmosaurid, Jucha squalea gen. et sp. nov., from the upper Hauterivian (Lower Cretaceous) of Ulyanovsk (European Russia), in addition to other elasmosaurid remains from the same area. Jucha squalea is one of the oldest and basalmost elasmosaurids known and lacks a series of features that otherwise characterize the group, such as the heart-shaped intercoracoid fenestra and the median pectoral bar. However, Jucha squalea marks an early attempt at cervical elongation through differential growth. The data we gathered on the shape of cervical centra among elasmosaurids suggest multiple episodes of elongation and shortening. However, the precise patterns are obscured by an unstable phylogenetic signal.

Keywords: cervical elongation, differential growth, Hauterivian, marine reptiles, Xenopsaria

   

Valentin Fischer, Nikolay G. Zverkov, Maxim S. Arkhangelsky, Ilya M. Stenshin, Ivan V. Blagovetshensky and Gleb N. Uspensky. 2020. A New Elasmosaurid Plesiosaurian from the Early Cretaceous of Russia marks An early Attempt at Neck Elongation. Zoological Journal of the Linnean Society. zlaa103.  DOI: 10.1093/zoolinnean/zlaa103

  twitter.com/Val_Fisch/status/1317043841854308352  

facebook.com/ValFisch/posts/10221501825227513

facebook.com/undorymuseum/posts/693236728281671

ulpressa.ru/2020/10/19/эласмозавр-из-ундоровского-палеонто

 

   

[Mollusca • 2020] A Synoptic Review of the Family Dendronotidae (Nudibranchia): A Multilevel Organismal Diversity Approach

Dendronotus yrjargul 

Korshunova, Bakken, Grøtan, Johnson, Lundin & Martynov, 2020

 DOI: 10.1163/18759866-BJA10014

 twitter.com/TorkildBakken

 ntnu.no 

Abstract

A synoptic review of the family Dendronotidae is presented based on morphological and molecular data. Three genera are recognized: Dendronotus, Pseudobornella, and Cabangus gen. nov. Two new Dendronotus species are described, D. yrjargul sp. nov. and D. nordenskioeldi sp. nov., which reveal fine-scale differences. Dendronotus yrjargul sp. nov. from mid-Norway and the Arctic regions is a sister species to the North Pacific D. kalikal. These two species are showing clear morphological and ontogenetic differences but are close in genetic distance. In contrast, Dendronotus nordenskioeldi sp. nov. from the Laptev Sea is externally similar to the white morphs of D. lacteus or D. frondosus, but according to the molecular data and radular morphology it is distinct from any of its congenerics. Comparison of molecular and morphological data of D. niveus from the type locality (White Sea) and material from other localities with those from the American North Atlantic coast (type locality of D. elegans) reveals their substantial similarity. Therefore, D. niveus is considered a junior synonym of D. elegans. The present review of the family Dendronotidae contributes to a general discussion on the species concepts and on a recent proposal of multilevel organismal diversity.

Keywords: Cabangus; Dendronotus; Pseudobornella; molecular phylogeny; species problem; taxonomy

Dendronotus yrjargul sp. nov.

Etymology. From Norwegian yrjar (=  old name for the type locality in Ørland) and gul (= yellow) meaning “yellow/golden of Ørland” in reference to the remarkable habitus of this species.

Distribution. From Norwegian Sea to Kara Sea. 

Dendronotus nordenskioeldi sp. nov. 

Etymology. In honour of Baron Nils Adolf Erik Nordenskiöld, outstanding Arctic explorer, geologist, and mineralogist. The Laptev Sea had been originally named “Nordenskiöld Sea”, after this Arctic explorer.

Distribution. So far known only from the Laptev Sea.

Representaives of the genus Dendronotus (living specimens).

 photographs by T. Korshunova, A. Martynov, K. Fletcher, D. Miller, Y. Fujiwara, K. Hasegawa, K. Sanamyan, N. Sanamyan, and O. Zimina

Genus Dendronotus Alder & Hancock, 1845 

Type species. Dendronotus frondosus (Ascanius, 1774)

Dendronotus albopunctatus Robilliard, 1972

Dendronotus albus MacFarland, 1966 

Dendronotus arcticus Korshunova, Sanamyan, Zimina, Fletcher & Martynov, 2016

Dendronotus bathyvela Martynov, Fujiwara, Tsuchida, R. Nakano, N. Sanamyan, K. Sanamyan, Fletcher & Korshunova, 2020

Dendronotus claguei Valdés, Lundsten & Wilson, 2018

Dendronotus comteti Valdés & Bouchet, 1998

Dendronotus dalli Bergh, 1879 

Dendronotus elegans Verrill, 1880 

Dendronotus europaeus Korshunova, Martynov, Bakken & Picton, 2017

Dendronotus frondosus (Ascanius, 1774) 

Dendronotus gracilis Baba, 1949 

Dendronotus iris Cooper, 1863 

Dendronotus jamsteci Martynov, Fujiwara, Tsuchida, R. Nakano, N. Sanamyan, K. Sanamyan, Fletcher & Korshunova, 2020

Dendronotus kalikal Ekimova, Korshunova, Shepetov, Neretina, Sanamyan & Martynov, 2015

Dendronotus kamchaticus Ekimova, Korshunova, Shepetov, Neretina, Sanamyan & Martynov, 2015

Dendronotus lacteus (Thompson, 1840) 

Dendronotus nanus Marcus & Marcus, 1967 

Dendronotus patricki Stout, Wilson & Valdés, 2011

Dendronotus primorjensis Martynov, Sanamyan & Korshunova, 2015

Dendronotus purpureus Bergh, 1879 

Dendronotus robilliardi Korshunova, Sanamyan, Zimina, Fletcher & Martynov, 2016

Dendronotus robustus Verrill, 1870 

Dendronotus rufus O’Donoghue, 1921 

Dendronotus subramosus MacFarland, 1966 

Dendronotus velifer G.O. Sars, 1878 

Dendronotus venustus MacFarland, 1966 

Dendronotus zakuro Martynov, Fujiwara, Tsuchida, R. Nakano, N. Sanamyan, K. Sanamyan, Fletcher & Korshunova, 2020

Genus Cabangus gen. nov. 

Type species. Dendronotus regius Pola & Stout, 2008

Etymology. From the Indonesian word “cabang” meaning “branch” in reference to this genus as “dendronotids of the tropics” and to respect the great contribution of the Indonesian fauna to global marine biodiversity (e.g., Hoeksema, 2007).

Cabangus noahi (Pola & Stout, 2008) comb. nov. 

Dendronotus noahi Pola & Stout, 2008: 55–63, figs 6A, B. 

Distribution. Papua New Guinea, north coast, outer barrier reef, Bagabag Island, Bismarck Sea.

Cabangus regius (Pola & Stout, 2008) comb. nov. 

Dendronotus regius Pola & Stout, 2008: 46– 54, Figs 1–5.

Distribution. Tropical Indo-west Pacific.

Genus Pseudobornella Baba, 1932 

Type species. P. orientalis Baba, 1932 

...

 Tatiana Korshunova, Torkild Bakken, Viktor V. Grøtan, Kjetil B. Johnson, Kennet Lundin and Alexander Martynov. 2020. A Synoptic Review of the Family Dendronotidae (Mollusca: Nudibranchia): A Multilevel Organismal Diversity Approach.   Contributions to Zoology. DOI: 10.1163/18759866-BJA10014

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Den gyldne nakensneglen fra Ørland, en ny og ukjent art 

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