Fossil impressions of pectinariid tubes (Polychaeta) in Miocene sediments of the Sakhalin Island

2017 ◽  
Vol 26 (2) ◽  
pp. 212-214 ◽  
Author(s):  
S.Yu. Gagaev

The fossil impressions of tubes belonging to the bristle worms of the family Pectinariidae and probably the genus Pectinaria Savigny, 1818 was found at the coastal cliffs of the Tartar Strait (Southern Sakhalin) in deposits of the late Miocene Kurasi Formation. Rare mentions of findings of impressions of the polychaetes tubes perhaps may be explained by the fact that such impressions are misidentified as fossils of animals from other higher taxa. Some new data on the bionomics of the recent pectinariids are given and some taphonomical aspects of the group are considered.

2020 ◽  
Vol 157 (8) ◽  
pp. 1378-1382
Author(s):  
Mikhail V. Nazarkin ◽  
Theodore W. Pietsch

AbstractThe almost complete skeleton of a fossil dreamer, identified as Oneirodes sp., is described from the middle–upper Miocene Kurasi Formation of southern Sakhalin Island, Russia. This is the second fossil skeletal record of oneirodid anglerfishes following those described from the Puente Formation of California, USA. The new specimen possesses morphological features very similar to those of the recent and fossil members of its genus, and cannot be separated from them at the species level. This finding confirms the idea of the high level of speciation of this fish family prior to the middle–late Miocene and demonstrates the wide geographic distribution of the genus Oneirodes already at this time.


1988 ◽  
Vol 62 (3) ◽  
pp. 463-467 ◽  
Author(s):  
Villarroel A. Carlos ◽  
Larry G. Marshall

A new argyrolagoid marsupial, Hondalagus altiplanensis n. gen., n. sp., from the middle Miocene (Santacrucian–Friasian) age locality of Quebrada Honda in southernmost Bolivia represents the smallest and most specialized member of the family Argyrolagidae known. The lower molars are hypselodont and lack vertical grooves labially and lingually, and M4 is greatly reduced relative to M3. In overall size and structure, H. altiplanensis compares best with Microtragulus catamarcensis (Kraglievich, 1931) from rocks of late Miocene (Huayquerian) age in northwest Argentina. Hondalagus altiplanensis demonstrates that the adaptive radiation of argyrolagoids was much greater than previously envisioned, and that generic differentiation of known taxa occurred no later than early–middle Miocene time in South America.


Author(s):  
Apolline ALFSEN ◽  
Mark BOSSELAERS ◽  
Olivier LAMBERT

In spite of a continuously expanding physeteroid fossil record, our understanding of the origin and early radiation of the two modern sperm whale families Kogiidae Gill, 1871 (including the pygmy and dwarf sperm whales, Kogia spp.) and Physeteridae Gray, 1821 (including the great sperm whale, Physeter Linnaeus, 1758) remains limited, especially due to the poorly resolved phylogenetic relationships of a number of extinct species. Among those, based on fragmentary cranial material from the late early to middle Miocene of Antwerp (Belgium, North Sea basin), the small-sized Thalassocetus antwerpiensis Abel, 1905 has been recognized for some time as the earliest branching kogiid. The discovery of a new diminutive physeteroid cranium from the late Miocene (Tortonian) of Antwerp leads to the description and comparison of a close relative of T. antwerpiensis. Thanks to the relatively young ontogenetic stage of this new specimen, the highly modified plate-like bones making the floor of its supracranial basin could be individually removed, a fact that greatly helped deciphering their identity and geometry. Close morphological similarities with T. antwerpiensis allow for the reassessment of several facial structures in the latter; the most important reinterpretation is the one of a crest-like structure, previously identified as a sagittal facial crest, typical for kogiids, and here revised as the left posterolateral wall of the supracranial basin, comprised of the left nasal (lost in kogiids for which the postnarial region is known) and the left maxilla. Implemented in a phylogenetic analysis, the new anatomical interpretations result in the new Belgian specimen and T. antwerpiensis being recovered as sister-groups in the family Physeteridae. Consequently, the geologically oldest kogiids are now dated from the Tortonian, further extending the ghost lineage separating these early late Miocene kogiid records from the estimated latest Oligocene to earliest Miocene divergence of kogiids and physeterids.


2020 ◽  
Vol 556 ◽  
pp. 109901
Author(s):  
Nadezhda Razjigaeva ◽  
Tatiana Grebennikova ◽  
Larisa Ganzey ◽  
Vladimir Ponomarev ◽  
Alexey Gorbunov ◽  
...  

2009 ◽  
Vol 60 (5) ◽  
pp. 419-430
Author(s):  
Lamara Maisuradze ◽  
Kakhaber Koiava ◽  
Silvia Spezzaferri

Taxonomic revision and new species/subspecies of Middle-Late Miocene (Bessarabian) miliolids of the Family Hauerinidae Schwager from Georgia — Eastern ParatethysThree new miliolid taxa from Bessarabian sediments from Georgia (Eastern Paratethys) are described following the classification of Łuczkowska (1972), which has never been used before by ex-Soviet micropaleontologists. They are:Varidentella luczkowskae; Varidentella reussi(Bogdanowicz) subsp.costulata; andAffinetrina voloshinovae(Bogdanowicz) subsp.eldarica.This classification takes into account the morphology of the aperture and the shape and size of teeth as criteria to distinguish the species. This study contributes important criteria which will help to unify the taxonomical inconsistencies between the Eastern, Central and Western Paratethyan miliolids.


2018 ◽  
Author(s):  
Sean A. Locke ◽  
Alex Van Dam ◽  
Monica Caffara ◽  
Hudson Alves Pinto ◽  
Danimar López-Hernández ◽  
...  

AbstractHigher systematics within the Digenea, Carus 1863 have been relatively stable since a phylogenetic analysis of partial nuclear ribosomal markers (rDNA) led to the erection of the Diplostomida Olson, Cribb, Tkach, Bray, and Littlewood, 2003. However, recent mitochondrial (mt) genome phylogenies suggest this order might be paraphyletic. These analyses show members of two diplostomidan superfamilies are more closely related to the Plagiorchiida La Rue, 1957 than to other members of the Diplostomida. In one of the groups implicated, the Diplostomoidea Poirier, 1886, a recent phylogeny based on mt DNA also indicates the superfamily as a whole is non-monophyletic. To determine if these results were robust to additional taxon sampling, we analyzed mt genomes from seven diplostomoids in three families. To choose between phylogenetic alternatives based on mt genomes and the prior rDNA-based topology, we also analyzed hundreds of ultra-conserved elements (UCEs) assembled from shotgun sequencing. The Diplostomida was paraphyletic in the mt genome phylogeny, but supported in the UCE phylogeny. We speculate this mitonuclear discordance is related to ancient, rapid radiation in the Digenea. Both UCEs and mt genomes support the monophyly of the Diplostomoidea and show congruent relationships within it. The Cyathocotylidae Mühling, 1898 are early diverging descendants of a paraphyletic clade of Diplostomidae Poirier, 1886, in which were nested members of the Strigeidae Railliet, 1919; the results support prior suggestions that the Crassiphialinae Sudarikov, 1960 will rise to the family level. Morphological traits of diplostomoid metacercariae appear to be more useful for differentiating higher taxa than those of adults. We describe a new species of Cotylurus Szidat, 1928, resurrect a species of Hysteromorpha Lutz, 1931, and find support for a species of Alaria Schrank, 1788 of contested validity. Complete rDNA operons are provided as a resource for future studies.


2019 ◽  
Vol 75 (3-4) ◽  
pp. 383-396
Author(s):  
Zhuding Qiu ◽  
Xijun Ni

Abstract Remains of platacanthomyids from Leilao, a late Miocene hominoid locality in Yuanmou, Yunnan, China are described. Five species in three genera are recognized: Neocometes sp., Platacanthomys dianensis Qiu, 1989, Typhlomys aff. T. primitivus Qiu, 1989, T. hipparionum Qiu, 1989 and T. storchi n. sp. Leilao is the only locality that produces fossils of all three known genera of the family Platacanthomyidae. The new species T. storchi is characterized by its huge dimensions and continuous endoloph(id)s and ectoloph(id)s incorporated with the anteroloph(id)s and posteroloph(id)s to encircle the occlusal surface. That the genus Neocometes from southeastern Asia shows a tendency of forming an ectoloph on the upper molars and an endolophid on the lower molars indicates that the South China species probably represents an evolutionary lineage independent from that of European Neocometes. Both P. dianensis and T. aff. T. primitivus exhibit more derived dental morphology than the related species from Shihuiba of Lufeng, suggesting a younger age of the Leilao Fauna, which is incompatible with the conclusion drawn from the studies of other groups of small mammals.


2016 ◽  
Vol 186 (3) ◽  
pp. 182-192
Author(s):  
Alexander G. Panov ◽  
Mikhail M. Tribun ◽  
Lyudmila I. Nikitina

Data on species composition of ciliates in the small rivers at Khabarovsk and in southern Sakhalin Island are presented. Modified method of sampling was applied with using of samplers and “glass fouling” on the shallows of the rivers. More than 230 samples were collected in the small rivers at Khabarovsk and about 200 samples in the southern Sakhalin. Species composition of the ciliates was determined immediately after the sampling and repeatedly on nutrient media. In total, 86 species of ciliates are identified, mostly belonged to the classes Oligohymenophorea and Spirotrichea. Six eurybionts were found: Coleps hirtus, Paramecium caudatum, Dexiostoma campylum, Colpidium colpoda, Uronema nigricans, and Vorticella convallaria сomplex . The classes Armophorea and Phyllopharyngea were more diverse by species in the area at Khabarovsk but the class Spirotrichea - in southern Sakhalin. In general, faunas of ciliates in two surveyed regions are similar. The highest inter-regional similarity of the species composition is registered between the rivers at Khabarovsk and the Susuya River in Sakhalin (25-33 %, by Jackaroo) that is probably associated with a heightened level of pollution in the Susuya. Most of the species adapt to habitat rapidly, so they are found in different environments: among benthos, plankton, periphyton. Some patterns of the ciliocommunities are discussed.


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