scholarly journals A new balaenopterid whale from the late Miocene of the Southern North Sea Basin and the evolution of balaenopterid diversity (Cetacea, Mysticeti)

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6915 ◽  
Author(s):  
Michelangelo Bisconti ◽  
Dirk K. Munsterman ◽  
Klaas Post
Keyword(s):  
Phylogenetic Analysis ◽  
North Sea ◽  
Sister Group ◽  
Morphological Characters ◽  
Monophyletic Group ◽  
New Taxon ◽  
Skull Morphology ◽  
The North ◽  
History Of ◽  
Morphological Transformations

Background Balaenopterid mysticetes represent the most successful family-rank group of this clade. Their evolutionary history is characterized by a rich fossil record but the origin of the living genera is still largely not understood. Recent discoveries in the southern border of the North Sea revealed a number of well preserved fossil balaenopterid whales that may help resolving this problem. In particular, skull NMR 14035 shares morphological characters with the living humpback whale, Megaptera novaeangliae and, for this reason, its characteristics are investigated here. Methods The comparative anatomical analysis of the new specimen formed the basis of a new phylogenetic analysis of the Mysticeti based on a matrix including 350 morphological character states scored for 82 Operational Taxonomic Units. The stratigraphic age of the specimen was determined based on the analysis of the dinocyst assemblage recovered in the associated sediment. We assessed clade diversity in Balaenopteridae by counting the numbers of clades in given time intervals and then plotted the results. Results Nehalaennia devossi n. gen. et sp. is described for the first time from the late Tortonian (8.7–8.1 Ma) of the Westerschelde (The Netherlands). This new taxon belongs to Balaenopteridae and shows a surprisingly high number of advanced characters in the skull morphology. Nehalaennia devossi is compared to a large sample of balaenopterid mysticetes and a phylogenetic analysis placed it as the sister group of a clade including the genus Archaebalaenoptera. The inclusion of this fossil allowed to propose a phylogenetic hypothesis for Balaenopteridae in which (1) Eschrichtiidae (gray whales) represents a family of its own, (2) Balaenopteridae + Eschrichtiidae form a monophyletic group (superfamily Balaenopteroidea), (3) Cetotheriidae is the sister group of Balaenopteroidea, (4) living Balaenoptera species form a monophyletic group and (5) living M. novaeangliae is the sister group of Balaenoptera. Our work reveals a complex phylogenetic history of Balaenopteridae and N. devossi informs us about the early morphological transformations in this family. Over time, this family experienced a number of diversity pulses suggesting that true evolutionary radiations had taken place. The paleoecological drivers of these pulses are then investigated.

scholarly journals Phylogeny of Libellula Linnaeus (Odonata: Insecta)

Zootaxa ◽  
2002 ◽  
Vol 87 (1) ◽  
pp. 1 ◽  
Author(s):  
FRANK LOUIS CARLE ◽  
KARL M. KJER
Keyword(s):  
Phylogenetic Analysis ◽  
Type Species ◽  
Sister Group ◽  
Morphological Characters ◽  
Sensu Stricto ◽  
Monophyletic Group ◽  
Representative Species

Phylogenetic analysis was performed on a set of 242 morphological characters. The taxon sample included 31 Libellula, and representative species from selected libeluline tribes, from all libellulid subfamilies, from all libelluloid families, from all anisopteran superfamilies, and Epiophlebia. Corduliinae was shown to be paraphyletic even among genera characterized by a well developed anal loop bisector. Sympetrini was found to be polyphyletic with Crocothemis the sister group to Libellulini. The traditional placement of Trameini, far from Libellulini is in doubt, because it is here placed as the sister group to Crocothemis + Libellulini. Kennedy’s phylogeny of Libellula was largely corroborated, with the following exceptions: the subgenera Libellula, Eolibellula, and Syntetrum form a monophyletic group which is the sister group to a clade including Belonia, Holotania, Neotetrum, and Eotainia subgenus nov. [type species Mesothemis composita Hagen]; and Eurothemis is determined to be the sister group of Ladona instead of Neotetrum. In addition we confirm Belonia to be monophyletic, and find Platetrum + Plathemis to form a monophyletic group, sister to Ladona + Eurothemis; these four subgenera together form the sister group to Libellula sensu stricto (s.s.).

scholarly journals A new balaenopterid species from the Southern North Sea Basin informs about phylogeny and taxonomy of Burtinopsis and Protororqualus (Cetacea, Mysticeti, Balaenopteridae)

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9570 ◽  
Author(s):  
Michelangelo Bisconti ◽  
Mark E.J. Bosselaers
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Atlantic Ocean ◽  
North Sea ◽  
North Atlantic Ocean ◽  
The Past ◽  
The North ◽  
The North Sea ◽  
Morphological Transformations ◽  
The 19Th Century

Background An extensive radiation can be inferred among balaenopterid mysticetes in the last 10 million years based on a rich fossil record. Many extinct genera and species have been established in the past by the study of fossil rorquals from northern and southern hemispheres. In many cases, the new fossils are used to create new genera. However, in very recent times, new species of known genera have been described that help our understanding of the speciation processes and the biogeography of these whales. Here, a new species of balaenopterid whales is described in order to better understand the past diversity of Balaenopteridae and to analyze its paleobiogeographical implications. As the new species closely resembles a taxon established in the 19th century (i.e., Burtinopsis), a detailed analysis of this taxon was necessary to support the new taxonomic statements of this article. Methods A new partial skeleton including skull and earbones is described and compared to an extended sample of living and fossil mysticete species. A phylogenetic analysis including 355 character states scored in 88 taxa was performed to understand its relationships within the genus Protororqualus, to allow paleobiogeographic inferences and to better understand the relationships of Protororqualus within Balaenopteridae. Maximum parsimony analyses of character evolution were performed to understand morphological transformations within Balaenopteridae. The revision of Burtinopsis was carried out based on detailed descriptions and comparisons of the type materials that were figured and measured. Results Protororqualus wilfriedneesi sp. nov. was established based on a comparative analysis of the skull and earbone morphology. The specimen is dated back to the Zanclean (Lower Pliocene, between c. 5.3 and 3.6 Ma). A taphonomical study of the holotype skeleton revealed evidence of interactions with sharks and fishes before the definitive burial of the carcass. Based on the phylogenetic analysis, the monophyly of the genus Protororqualus was confirmed. Protororqualus wilfriedneesi sp. nov. was more derived than Protororqualus cuvieri suggesting that it resulted from an invasion of the North Sea Basin (and the North Atlantic ocean) from the Mediterranean basin. Several specimens from western and eastern sides of the Atlantic Ocean are described that suggest that Protororqualus wilfriedneesi had a trans-Atlantic distribution in the Pliocene.

scholarly journals Phylogeny of the Anomura (Decapoda, Crustacea): Spermatozoa and spermatophore morphological evidence

1997 ◽  
Vol 67 (2) ◽  
pp. 125-141 ◽  
Author(s):  
Christopher C. Tudge
Keyword(s):  
Phylogenetic Analysis ◽  
Decapod Crustacean ◽  
Sister Group ◽  
Morphological Characters ◽  
The Other ◽  
Monophyletic Group ◽  
Morphological Evidence ◽  
Monophyletic Clade ◽  
The Family ◽  
Single Clade

A phylogenetic analysis of selected anomuran, thalassinidean, and other decapod crustacean taxa, based on spermatozoal ultrastructural characters and spermatophore morphological characters, was performed and the following relationships of the taxa are elucidated from the trees produced. The Anomura are not a monophyletic assemblage, with the lomoid Lomis being exclusive of the remainder of the anomuran taxa, and the thalassinid Thalassina included in the anomuran clade. The synapomorphy joining the majority of the conventional anomuran taxa (Lomis excluded) is the cytoplasmic origin of the microtubular arms. When the palinurid and thalassinoid representatives are separately designated as outgroups, the Astacidea and Brachyura jointly formed a sister group to the Anomura. The superfamilies Thalassinoidea, Paguroidea, and Galatheoidea are not monophyletic groups. In all analyses the anomuran families Coenobitidae and Porcellanidae each form a monophyletic group. The paguroid family Diogenidae is paraphyletic, with the genera Clibanarius and Cancellus separate from a single clade containing the remaining diogenid genera. The families Paguridae and Parapaguridae form a monophyletic clade with the exception of Porcellanopagurus. The two representatives of the family Chirostylidae (Eumunida and Uroptychus) fail to associate with the other species in the Galatheoidea. The taxa in the family Galatheidae are not a monophyletic assemblage. The only investigated hippoid Hippa is portrayed as the sister group to the remainder of the anomuran taxa (with the exception of Lomis).

The genus Sciarotricha gen. n. (Sciaridae) and the phylogeny of recent and fossil Sciaroidea (Diptera)

2005 ◽  
Vol 36 (2) ◽  
pp. 121-143 ◽  
Author(s):  
Pekka Vilkamaa ◽  
Heikki Hippa
Keyword(s):  
Phylogenetic Analysis ◽  
Sister Group ◽  
Morphological Characters ◽  
The Other ◽  
New Taxon ◽  
Parsimony Analysis ◽  
Cladistic Analyses ◽  
Phylogenetic Hypotheses

AbstractThe phylogeny of the main groups of the Sciaroidea, including the fossil Antefungivoridae, Archizelmiridae, Mesosciophilidae, Pleciofungivoridae, Pleciomimidae, Protopleciidae and Bolitophilidae: Mangasinae, and an extant new taxon, was studied by parsimony analysis. Two cladistic analyses of seventy-eight morphological characters from adults were made. One analysis, with forty-one extant taxa in the ingroup and the other, with the addition of twelve fossil taxa, both produced two most parsimonious cladograms. The phylogenetic hypotheses obtained differed from each other, and in part also to a great extent from previous ones although most of the traditionally recognized groups appeared monophyletic, including the speciose Cecidomyiidae and Sciaridae. The Cecidomyiidae (fossil analysis) or the Keroplatidae-Ditomyiidae (extant analysis) appeared as the sister-group of the rest of the Sciaroidea. Following on from these analyses, we propose emending the current Sciaridae to include the following subfamilies: Archizelmirinae stat. n., Rangomaraminae stat. n., Sciarinae, Sciarosominae subfam. n. and Sciarotrichinae subfam. n. A new taxon from Namibia, Sciarotricha biloba gen. n., sp. n. is described, and, according to the phylogenetic analysis, is placed in the Sciaridae (Sciarotrichinae). The sister-group of the Sciaridae as newly defined is the Mycetophilidae group, in the extant analysis including the Mycetophilidae, Manotidae, Lygistorrhinidae, Pterogymnus and Sciaropota, and in the fossil analysis even including the Mesosciophilidae and the Ohakunea group (Ohakunea + Colonomyia).

scholarly journals Phylogeny and Synonymy of Gyrodinium heterostriatum comb. nov. (Dinophyceae), a Common Unarmored Dinoflagellate in the World Oceans [plus supplementary materials]

2020 ◽  
Vol 59 (2) ◽  
pp. 77-87
Author(s):  
Fernando Gómez ◽  
Luis F. Artigas ◽  
Rebecca J. Gast
Keyword(s):  
North Sea ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Morphological Plasticity ◽  
Sister Group ◽  
Rrna Gene ◽  
Microbial World ◽  
The North ◽  
The North Sea ◽  
Environmental Sequences

The North Sea and the English Channel are regions with a long tradition of plankton studies, where the colony-forming haptophyte Phaeocystis globosa dominates the spring phytoplankton blooms. Among its predators, we investigated an abundant unarmored dinoflagellate (~3000 cells per liter) in the North Sea in May 2019. It has been reported in the literature as Gymnodinium heterostriatum or G. striatissimum, and often identified as Gyrodinium spirale. Phylogenetic analyses using the small-, large subunit- and Internal Transcriber Spacers of the ribosomal RNA (SSU-, LSU-, ITS rRNA) gene sequences indicate that our isolates clustered within the Gyrodinium clade. The new sequences formed a sister group with sequences of the freshwater taxon Gyrodinium helveticum, being one of the infrequent marine-freshwater transitions in the microbial world. This isolate is the first characterized member of a clade of numerous environmental sequences widely distributed from cold to tropical seas. This common and abundant taxon has received several names due to its morphological plasticity (changes of size and shape, often deformed after engulfing prey) and the difficulty in discerning surface striation. We conclude that the priority is for the species name Gymnodinium heterostriatum Kofoid & Swezy 1921, a new name that was proposed for Gymnodinium spirale var. obtusum sensu Dogiel 1906. The species Gyrodinium striatissimum (Hulburt 1957) Gert Hansen & Moestrup 2000 and Gymnodinium lucidum D. Ballantine in Parke & Dixon 1964 (=G. hyalinum M. Lebour 1925) are posterior synonyms. We propose Gyrodinium heterostriatum comb. nov. for Gymnodinium heterostriatum.

scholarly journals A new iguanodontian (Dinosauria: Ornithopoda) from the Early Cretaceous of Mongolia

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5300
Author(s):  
Terry A. Gates ◽  
Khishigjav Tsogtbaatar ◽  
Lindsay E. Zanno ◽  
Tsogtbaatar Chinzorig ◽  
Mahito Watabe
Keyword(s):  
Phylogenetic Analysis ◽  
Growth Stage ◽  
Phylogenetic Analyses ◽  
Type Specimen ◽  
Sister Taxon ◽  
New Taxon ◽  
Time Of Death ◽  
The North ◽  
Unusual Combination ◽  
Relationship Of

We describe a new iguanodontian ornithopod,Choyrodon barsboldigen. et sp. nov. from the Albian-aged Khuren Dukh Formation of Mongolia based on several partial skeletons interpreted to represent a subadult growth stage based on osteohistological features. This new taxon is diagnosed by many autapomorphies of the maxilla, nasal, lacrimal, opisthotic, predentary, and surangular.Choyrodondisplays an unusual combination of traits, possessing an open antorbital fenestra (a primitive ornithopod trait) together with derived features such as a downturned dentary and enlarged narial fenestra. Histological imaging suggests that the type specimen ofChoyrodonwould have been a subadult at the time of death. Phylogenetic analysis of two different character matrices do not positChoyrodonto be the sister taxon or to be more primitive than the iguanodontianAltirhinus kurzanovi, which is found in the same formation. The only resolved relationship of this new taxon is that it was hypothesized to be a sister-taxon with the North American speciesEolambia caroljonesa. Though discovered in the same formation andChoyrodonbeing smaller-bodied thanAltirhinus, it does not appear that the former species is an ontogimorph of the latter. Differences in morphology and results of the phylogenetic analyses support their distinction although more specimens of both species will allow better refinement of their uniqueness.

A Case History of Casing Directional Drilling in the Norwegian Sector of the North Sea

2008 ◽  
Author(s):  
Kevin Arthur Bourassa ◽  
Tove Husby ◽  
Rick Deuane Watts ◽  
Dale Oveson ◽  
Tommy M. Warren ◽  
...  
Keyword(s):  
North Sea ◽  
Case History ◽  
Directional Drilling ◽  
The North ◽  
History Of ◽  
The North Sea

scholarly journals A New Cypselomorph Bird from the Middle Eocene of Germany and the Early Diversification of Avian Aerial Insectivores

The Condor ◽  
2005 ◽  
Vol 107 (2) ◽  
pp. 342-352 ◽  
Author(s):  
Gerald Mayr
Keyword(s):  
Phylogenetic Analysis ◽  
Middle Eocene ◽  
Sister Group ◽  
Food Competition ◽  
Early Miocene ◽  
New Taxon ◽  
Insectivorous Birds ◽  
Dominant Group ◽  
Early Diversification ◽  
Aerial Insectivores

Abstract A new taxon of the Cypselomorphae—the clade including nightjars, potoos, owlet-nightjars, and apodiform birds—is described from the middle Eocene of Messel in Germany. Phylogenetic analysis of 49 characters shows Protocypselomorphus manfredkelleri gen. et sp. nov. to be the sister group of all other cypselomorph taxa, although this placement was not robust to bootstrapping. As evidenced by its swift-like beak, long forearm, and reduced feet, P. manfredkelleri was hawking insects on the wing. Thus it adds a distinctive new taxon to the already diverse assemblage of Paleogene aerial insectivores, all of which belong to the Cypselomorphae. This strongly contrasts with the extant avifauna where many aerial insectivores belong to songbirds, and among the insectivorous cypselomorph taxa only swifts and nightjars are species rich and widely distributed. The diversity of aerial insectivores among the Cypselomorphae may have been reduced by food competition with songbirds, which do not become the dominant group of insectivorous birds before the early Miocene. Una Nueva Ave Cipselomorfa del Eoceno Medio de Alemania y la Diversificación Temprana de las Aves Insectívoras Aéreas Resumen. Se describe un nuevo taxón de Cypselomorphae, el clado que incluye a las familias Caprimulgidae, Nyctibiidae, Aegothelidae y a las aves apodiformes, del Eoceno medio de Messel en Alemania. Un análisis filogenético de 49 caracteres muestra que Protocypselomorphus manfredkelleri gen. et sp. nov. es el grupo hermano de los demás taxa de cipselomorfos, aunque esta posición no fue apoyada por el análisis de bootstrap. Como lo evidencia su pico tipo vencejo, antebrazo largo y patas pequeñas, P. manfredkelleri cazaba insectos al vuelo. Así, este hallazgo añade un nuevo taxón al grupo ya diverso de los insectívoros aéreos del Paleógeno, todos los cuales pertenecen al grupo de los cipselomorfos. Esto contrasta fuertemente con la avifauna actual, en que muchos insectívoros aéreos pertenecen al grupo de los paseriformes, mientras que de los taxa de insectívoros cipselomorfos sólo los apodiformes y caprimúlgidos presentan alta diversidad específica y se encuentran ampliamente distribuidos. La diversidad de los insectívoros aéreos en los cipselomorfos pude haberse reducido debido a la competencia por alimento con las aves paseriformes, las cuales no se transforman en el grupo dominante de aves insectívoras sino hasta el Mioceno temprano.

The history and future of the North Sea benthos

1978 ◽  
Vol 76 (1-3) ◽  
pp. 193-200
Author(s):  
P. E. P. Norton
Keyword(s):  
North Sea ◽  
Bottom Type ◽  
The North ◽  
Late Tertiary ◽  
Long Term Changes ◽  
History Of ◽  
The North Sea ◽  
Temperature Depth

SynopsisThis is a brief review intended to supply bases for prediction of future changes in the North Sea Benthos. It surveys long-term changes which are affecting the benthos. Any prediction must take into account change in temperature, depth, bottom type, tidal patterns, current patterns and zoogeography of the sea and the history of these is briefly touched on from late Tertiary times up to the present. From a prediction of changes in the benthos, certain information concerning the pelagic and planktonic biota could also be derived.

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