scholarly journals A partial skeleton of Septencoracias from the early Eocene London Clay reveals derived features of bee-eaters (Meropidae) in a putative stem group roller (Aves, Coracii)

2021 ◽  
Author(s):  
Gerald Mayr
Keyword(s):  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Sister Taxon ◽  
Early Eocene ◽  
Foraging Mode ◽  
Ecological Preferences ◽  
Stem Group ◽  
London Clay ◽  
Fossil Records ◽  
Partial Skeleton

AbstractA partial skeleton of the putative stem group roller Septencoracias is described from the early Eocene London Clay of Walton-on-the-Naze (Essex, UK). With an age of about 55 million years, the bones represent one of the earliest fossil records of a coraciiform bird. The new fossil reveals that the proximal pedal phalanges of the three anterior toes of Septencoracias exhibit markedly widened distal ends. This distinctive trait is not found in other representatives of the Coracii, but occurs in the Meropidae (bee-eaters). The quadrate likewise exhibit a derived characteristic of the Meropidae, and the beak is narrower than in rollers. These previously unnoticed features are of particular interest, because the Meropidae result as the sister taxon of the Coracii in sequence-based analyses. Calibrated molecular data suggest that the divergence between the Coracii and the Meropidae occurred at 55.6 Ma, with the new fossil being only slightly younger than this date. However, phylogenetic analyses recovered Septencoracias within the Coracii, so that the derived features shared with the Meropidae most likely are either plesiomorphic and were lost in the Coracii, or they represent parallelisms that evolved convergently in Septencoracias and the Meropidae. In any case, these traits suggest that Septencoracias differed from extant rollers in its ecological preferences and foraging mode.

scholarly journals Ancestral morphology of Ecdysozoa constrained by an early Cambrian stem group ecdysozoan

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Richard J. Howard ◽  
Gregory D. Edgecombe ◽  
Xiaomei Shi ◽  
Xianguang Hou ◽  
Xiaoya Ma
Keyword(s):  
Feeding Strategy ◽  
Phylogenetic Analyses ◽  
Morphological Diversity ◽  
Early Cambrian ◽  
Ancestral State ◽  
Crown Group ◽  
Stem Group ◽  
Chengjiang Biota ◽  
Fossil Records ◽  
Experimental Decay

Abstract Background Ecdysozoa are the moulting protostomes, including arthropods, tardigrades, and nematodes. Both the molecular and fossil records indicate that Ecdysozoa is an ancient group originating in the terminal Proterozoic, and exceptional fossil biotas show their dominance and diversity at the beginning of the Phanerozoic. However, the nature of the ecdysozoan common ancestor has been difficult to ascertain due to the extreme morphological diversity of extant Ecdysozoa, and the lack of early diverging taxa in ancient fossil biotas. Results Here we re-describe Acosmia maotiania from the early Cambrian Chengjiang Biota of Yunnan Province, China and assign it to stem group Ecdysozoa. Acosmia features a two-part body, with an anterior proboscis bearing a terminal mouth and muscular pharynx, and a posterior annulated trunk with a through gut. Morphological phylogenetic analyses of the protostomes using parsimony, maximum likelihood and Bayesian inference, with coding informed by published experimental decay studies, each placed Acosmia as sister taxon to Cycloneuralia + Panarthropoda—i.e. stem group Ecdysozoa. Ancestral state probabilities were calculated for key ecdysozoan nodes, in order to test characters inferred from fossils to be ancestral for Ecdysozoa. Results support an ancestor of crown group ecdysozoans sharing an annulated vermiform body with a terminal mouth like Acosmia, but also possessing the pharyngeal armature and circumoral structures characteristic of Cambrian cycloneuralians and lobopodians. Conclusions Acosmia is the first taxon placed in the ecdysozoan stem group and provides a constraint to test hypotheses on the early evolution of Ecdysozoa. Our study suggests acquisition of pharyngeal armature, and therefore a change in feeding strategy (e.g. predation), may have characterised the origin and radiation of crown group ecdysozoans from Acosmia-like ancestors.

scholarly journals An Exceptionally Preserved Specimen From the Green River Formation Elucidates Complex Phenotypic Evolution in Gruiformes and Charadriiformes

2020 ◽  
Vol 8 ◽  
Author(s):  
Grace Musser ◽  
Julia A. Clarke
Keyword(s):  
Fossil Record ◽  
Phylogenetic Analyses ◽  
Divergence Time ◽  
Axial Skeleton ◽  
Green River Formation ◽  
New Taxon ◽  
Early Eocene ◽  
Phenotypic Evolution ◽  
Green River ◽  
Partial Skeleton

The stem lineage relationships and early phenotypic evolution of Charadriiformes (shorebirds) and Gruiformes (rails, cranes, and allies) remain unresolved. It is still debated whether these clades are sister-taxa. New phylogenetic analyses incorporating Paleogene fossils have the potential to reveal the evolutionary connections of these two speciose and evolutionarily critical neoavian subclades. Although Gruiformes have a rich Paleogene fossil record, most of these fossils have not been robustly placed. The Paleogene fossil record of Charadriiformes is scarce and largely consists of fragmentary single elements. Only one proposed Eocene charadriiform-like taxon, Scandiavis mikkelseni of Denmark, is represented by a partial skeleton. Here, we describe a new species from the early Eocene Green River Formation of North America comprising a partial skeleton and feather remains. Because the skeleton lacks the pectoral girdle and forelimbs as in S. mikkelseni, only features of the skull, axial skeleton, and hind limb are available to resolve the phylogenetic placement of this taxon. These anatomical subregions initially showed features seen in Charadriiformes and Gruiformes. To assess placement of this taxon, we use a matrix consisting of 693 morphological characters and 60 taxa, including S. mikkelseni and the oldest known charadriiform taxa represented by single elements. These more fragmentary records comprise two distal humeri from the earliest Eocene Naranbulag Formation of Mongolia and the early Eocene Nanjemoy Formation of Virginia. Our phylogenetic analyses recover the new taxon and S. mikkelseni alternatively as a charadriiform or as a stem-gruiform; placement is contingent upon enforced relationships for major neoavian subclades recovered by recent molecular-based phylogenies. Specifically, when constraint trees based on results that do not recover Charadriiformes and Gruiformes as sister-taxa are used, the new taxon and S. mikkelseni are recovered within stem Gruiformes. Both Paleogene fossil humeri are consistently recovered within crown Charadriiformes. If placement of these humeri or the new taxon as charadriiforms are correct, this may indicate that recent divergence time analyses have underestimated the crown age of another major crown avian subclade; however, more complete sampling of these taxa is necessary, especially of more complete specimens with pectoral elements.

scholarly journals A partial skeleton of a new species of Tynskya Mayr, 2000 (Aves, Messelasturidae) from the London Clay highlights the osteological distinctness of a poorly known early Eocene “owl/parrot mosaic”

PalZ ◽  
2021 ◽  
Author(s):  
Gerald Mayr
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Cervical Vertebrae ◽  
Data Matrix ◽  
Sister Group Relationship ◽  
Single Individual ◽  
Early Eocene ◽  
Skeletal Morphology ◽  
London Clay ◽  
A New Species

AbstractTynskya eocaena is an early Eocene bird with a raptor-like skull and semi-zygodactyl feet, whose description is based on a skeleton from the North American Green River Formation. In the present study, three-dimensionally preserved bones of a new species of Tynskya, T. waltonensis, are reported from the London Clay of Walton-on-the-Naze (Essex, UK). The fossils belong to a single individual and provide new insights into the skeletal morphology of messelasturids. In particular, they reveal unusual vertebral specializations, with the cervical vertebrae having concave rather than saddle-shaped caudal articulation facets and the caudalmost thoracic vertebra being platycoelous (flat articular surfaces). The very deep mandible and a derived morphology of the ungual phalanges support a sister group relationship between Tynskya and the taxon Messelastur (Messelasturidae). Phylogenetic analyses of an emended data matrix did not conclusively resolve the higher-level affinities of messelasturids and the closely related halcyornithids, with both taxa sharing derived characters with only distantly related extant taxa (Accipitriformes, Strigiformes, Falconiformes, and Psittaciformes). An analysis that was constrained to a molecular scaffold, however, recovered messelasturids as the sister taxon of a clade including psittaciform and passeriform birds. The derived morphologies of the mandible and cervical vertebrae suggest specialized feeding adaptations of Tynskya, and messelasturids may have exploited a feeding niche, which is no longer available to extant birds.

scholarly journals Linking morphological and molecular sources to disentangle the case of Xylodon australis

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Javier Fernández-López ◽  
M. Teresa Telleria ◽  
Margarita Dueñas ◽  
Mara Laguna-Castro ◽  
Klaus Schliep ◽  
...  
Keyword(s):  
New Zealand ◽  
Phylogenetic Analyses ◽  
Single Species ◽  
R Package ◽  
Molecular Data ◽  
Historical Collections ◽  
Close Relationship ◽  
Kinship Relations ◽  
History Of ◽  
Different Sources

AbstractThe use of different sources of evidence has been recommended in order to conduct species delimitation analyses to solve taxonomic issues. In this study, we use a maximum likelihood framework to combine morphological and molecular traits to study the case of Xylodon australis (Hymenochaetales, Basidiomycota) using the locate.yeti function from the phytools R package. Xylodon australis has been considered a single species distributed across Australia, New Zealand and Patagonia. Multi-locus phylogenetic analyses were conducted to unmask the actual diversity under X. australis as well as the kinship relations respect their relatives. To assess the taxonomic position of each clade, locate.yeti function was used to locate in a molecular phylogeny the X. australis type material for which no molecular data was available using morphological continuous traits. Two different species were distinguished under the X. australis name, one from Australia–New Zealand and other from Patagonia. In addition, a close relationship with Xylodon lenis, a species from the South East of Asia, was confirmed for the Patagonian clade. We discuss the implications of our results for the biogeographical history of this genus and we evaluate the potential of this method to be used with historical collections for which molecular data is not available.

scholarly journals The Complete DNA Sequence of the Mitochondrial Genome of a “Living Fossil,” the Coelacanth (Latimeria chalumnae)

Genetics ◽  
1997 ◽  
Vol 146 (3) ◽  
pp. 995-1010 ◽  
Author(s):  
Rafael Zardoya ◽  
Axel Meyer
Keyword(s):  
Mitochondrial Genome ◽  
Tandem Repeats ◽  
Phylogenetic Analyses ◽  
Large Data ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Data Set ◽  
Living Fossil ◽  
Latimeria Chalumnae ◽  
Relationship Of

The complete nucleotide sequence of the 16,407-bp mitochondrial genome of the coelacanth (Latimeria chalumnae) was determined. The coelacanth mitochondrial genome order is identical to the consensus vertebrate gene order which is also found in all ray-finned fishes, the lungfish, and most tetrapods. Base composition and codon usage also conform to typical vertebrate patterns. The entire mitochondrial genome was PCR-amplified with 24 sets of primers that are expected to amplify homologous regions in other related vertebrate species. Analyses of the control region of the coelacanth mitochondrial genome revealed the existence of four 22-bp tandem repeats close to its 3′ end. The phylogenetic analyses of a large data set combining genes coding for rRNAs, tRNA, and proteins (16,140 characters) confirmed the phylogenetic position of the coelacanth as a lobe-finned fish; it is more closely related to tetrapods than to ray-finned fishes. However, different phylogenetic methods applied to this largest available molecular data set were unable to resolve unambiguously the relationship of the coelacanth to the two other groups of extant lobe-finned fishes, the lungfishes and the tetrapods. Maximum parsimony favored a lungfish/coelacanth or a lungfish/tetrapod sistergroup relationship depending on which transversion:transition weighting is assumed. Neighbor-joining and maximum likelihood supported a lungfish/tetrapod sistergroup relationship.

scholarly journals Loose Ends in the Cortinarius Phylogeny: Five New Myxotelamonoid Species Indicate a High Diversity of These Ectomycorrhizal Fungi with South American Nothofagaceae

Life ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 420
Author(s):  
María Eugenia Salgado Salomón ◽  
Carolina Barroetaveña ◽  
Tuula Niskanen ◽  
Kare Liimatainen ◽  
Matthew E. Smith ◽  
...  
Keyword(s):  
New Species ◽  
Current Knowledge ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Global Scale ◽  
South American ◽  
Edible Fungi ◽  
Rdna Its ◽  
Morphological And Molecular Data ◽  
High Diversity

This paper is a contribution to the current knowledge of taxonomy, ecology and distribution of South American Cortinarius (Pers.) Gray. Cortinarius is among the most widely distributed and species-rich basidiomycete genera occurring with South American Nothofagaceae and species are found in many distinct habitats, including shrublands and forests. Due to their ectomycorrhizal role, Cortinarius species are critical for nutrient cycling in forests, especially at higher latitudes. Some species have also been reported as edible fungi with high nutritional quality. Our aim is to unravel the taxonomy of selected Cortinarius belonging to phlegmacioid and myxotelamonioid species based on morphological and molecular data. After widely sampling Cortinarius specimens in Patagonian Nothofagaceae forests and comparing them to reference collections (including holotypes), we propose five new species of Cortinarius in this work. Phylogenetic analyses of concatenated rDNA ITS-LSU and RPB1 sequences failed to place these new species into known Cortinarius sections or lineages. These findings highlight our knowledge gaps regarding the fungal diversity of South American Nothofagaceae forests. Due to the high diversity of endemic Patagonian taxa, it is clear that the South American Cortinarius diversity needs to be discovered and described in order to understand the evolutionary history of Cortinarius on a global scale.

scholarly journals Disentangling relationships among eastern Mediterranean Cymbalaria including description of a novel species from the southern Peloponnese (Greece)

2021 ◽  
Vol 307 (2) ◽  
Author(s):  
Pau Carnicero ◽  
Núria Garcia-Jacas ◽  
Llorenç Sáez ◽  
Theophanis Constantinidis ◽  
Mercè Galbany-Casals
Keyword(s):  
Eastern Mediterranean ◽  
Phylogenetic Analyses ◽  
Taxonomic Revision ◽  
Distribution Patterns ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Long Distance ◽  
Aegean Islands ◽  
Molecular Phylogenetic

AbstractThe eastern Mediterranean basin hosts a remarkably high plant diversity. Historical connections between currently isolated areas across the Aegean region and long-distance dispersal events have been invoked to explain current distribution patterns of species. According to most recent treatments, at least two Cymbalaria species occur in this area, Cymbalaria microcalyx and C. longipes. The former comprises several intraspecific taxa, treated at different ranks by different authors based on morphological data, evidencing the need of a taxonomic revision. Additionally, some populations of C. microcalyx show exclusive morphological characters that do not match any described taxon. Here, we aim to shed light on the systematics of eastern Mediterranean Cymbalaria and to propose a classification informed by various sources of evidence. We performed molecular phylogenetic analyses using ITS, 3’ETS, ndhF and rpl32-trnL sequences and estimated the ploidy level of some taxa performing relative genome size measures. Molecular data combined with morphology support the division of traditionally delimited C. microcalyx into C. acutiloba, C. microcalyx and C. minor, corresponding to well-delimited nrDNA lineages. Furthermore, we propose to combine C. microcalyx subsp. paradoxa at the species level. A group of specimens previously thought to belong to Cymbalaria microcalyx constitute a well-defined phylogenetic and morphological entity and are described here as a new species, Cymbalaria spetae. Cymbalaria longipes is non-monophyletic, but characterized by being glabrous and diploid, unlike other eastern species. The nrDNA data suggest at least two dispersals from the mainland to the Aegean Islands, potentially facilitated by marine regressions.

scholarly journals Redescription of Paradiplozoon hemiculteri (Monogenea, Diplozoidae) from the type host Hemiculter leucisculus, with neotype designation

Parasite ◽  
2018 ◽  
Vol 25 ◽  
pp. 4 ◽  
Author(s):  
Dagmar Jirsová ◽  
Xuejuan Ding ◽  
Kristína Civáňová ◽  
Eliška Jirounková ◽  
Jana Ilgová ◽  
...  
Keyword(s):  
Southern China ◽  
Phylogenetic Analyses ◽  
Posterior Part ◽  
Original Description ◽  
Molecular Data ◽  
The Body ◽  
Type Host ◽  
Hemiculter Leucisculus ◽  
Morphological And Molecular Data ◽  
Median Plate

Paradiplozoon hemiculteri (Ling, 1973), a member of the Diplozoidae, parasitizes the gills of Asian fish. Not only is the type material unavailable for this species, the original description was poor and somewhat conflicting, and adequate molecular data were not available. What is more, the available morphological and molecular data are inconsistent and fluctuate significantly. Here, we present a redescription of P. hemiculteri based on morphological and molecular data from new isolates collected from the type host, the sharpbelly Hemiculter leucisculus (Basilewsky, 1855), captured at the neotype locality (Shaoguan, Guangdong Province, southern China); a neotype for P. hemiculteri was designated from this collection. The length and width of the body, buccal suckers, pharynx, attachment clamps, sickle and the central hook handle were all measured and the shape of the anterior and posterior part of the median plate and anterior and posterior joining sclerites accurately documented. Phylogenetic analyses based on the sequences of the second rDNA internal transcribed spacer (ITS2) indicated that all new samples clustered together and differed clearly from sequences attributed to P. hemiculteri, which are deposited in GenBank. Our results confirm that P. hemiculteri is the only diplozoid that has demonstrably been found on the gills of H. leucisculus to date.

scholarly journals Molecular and Biological Characterisation of Turnip mosaic virus Isolates Infecting Poppy (Papaver somniferum and P. rhoeas) in Slovakia

Viruses ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 430 ◽  
Author(s):  
Miroslav Glasa ◽  
Katarína Šoltys ◽  
Lukáš Predajňa ◽  
Nina Sihelská ◽  
Slavomíra Nováková ◽  
...  
Keyword(s):  
Mosaic Virus ◽  
Phylogenetic Analyses ◽  
Molecular Data ◽  
Turnip Mosaic Virus ◽  
Biological Assays ◽  
Genetic Complexity ◽  
The World ◽  
History Of ◽  
Virus Isolates

In recent years, the accumulated molecular data of Turnip mosaic virus (TuMV) isolates from various hosts originating from different parts of the world considerably helped to understand the genetic complexity and evolutionary history of the virus. In this work, four complete TuMV genomes (HC9, PK1, MS04, MS15) were characterised from naturally infected cultivated and wild-growing Papaver spp., hosts from which only very scarce data were available previously. Phylogenetic analyses showed the affiliation of Slovak Papaver isolates to the world-B and basal-B groups. The PK1 isolate showed a novel intra-lineage recombination pattern, further confirming the important role of recombination in the shaping of TuMV genetic diversity. Biological assays indicated that the intensity of symptoms in experimentally inoculated oilseed poppy are correlated to TuMV accumulation level in leaves. This is the first report of TuMV in poppy plants in Slovakia.

Affinities of the Boletus chromapes group to Royoungia and the description of two new genera, Harrya and Australopilus

2012 ◽  
Vol 25 (6) ◽  
pp. 418 ◽  
Author(s):  
Roy E. Halling ◽  
Mitchell Nuhn ◽  
Todd Osmundson ◽  
Nigel Fechner ◽  
James M. Trappe ◽  
...  
Keyword(s):  
New Genus ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Elongation Factor ◽  
Sister Group ◽  
Molecular Data ◽  
Translation Elongation ◽  
Spore Deposit ◽  
Large Subunit Rdna ◽  
Translation Elongation Factor 1Α

Harrya is described as a new genus of Boletaceae to accommodate Boletus chromapes, a pink-capped bolete with a finely scabrous stipe adorned with pink scabers, a chrome yellow base and a reddish-brown spore deposit. Phylogenetic analyses of large-subunit rDNA and translation elongation factor 1α confirmed Harrya as a unique generic lineage with two species, one of which is newly described (H. atriceps). Some Chinese taxa were recently placed in a separate genus, Zangia, supported by both morphology and molecular data. Multiple accessions from Queensland, Australia, support the synonymy of at least three species in a separate Australian clade in the new genus, Australopilus. The truffle-like Royoungia is also supported as a separate lineage in this clade of boletes. Even though it lacks stipe characters, it possesses the deep, bright yellow to orange pigments in the peridium. Additional collections from Zambia and Thailand represent independent lineages of uncertain phylogenetic placement in the Chromapes complex, but sampling is insufficient for formal description of new species. Specimens from Java referable to Tylopilus pernanus appear to be a sister group of the Harrya lineage.

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