scholarly journals A new short-necked chelid turtle from the Loncoche Formation (Late Campanian- Early Maastrichtian) Mendoza province, Argentina: Macro, microanatomy, and preliminary phylogenetic relationships

2015 ◽  
Author(s):  
Marcelo de la Fuente ◽  
Ignacio Maniel ◽  
Juan Marcos Jannello ◽  
Juliana Sterli ◽  
Bernardo González Riga ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Cancellous Bone ◽  
Phylogenetic Relationships ◽  
Cervical Vertebrae ◽  
Data Matrix ◽  
Appendicular Skeleton ◽  
Thin Sections ◽  
Lower Jaw ◽  
A New Species ◽  
Preliminary Phylogenetic Analysis

Background. The lower section of the Loncoche Formation (Late Campanian-Early Maastrichtian) outcropping at Ranquil-Có locality (Mendoza province, Argentina) has yielded a rich assemblage of vertebrates that was studied in 1995 by Gonzalez Riga. According to this author these vertebrate remains were found in a tidal paleoenvironment, resulting from transportation, mixing and deposition of continental remains mixed with those from near costal environments. Previously to these findings Jose F. Bonaparte recovered in 1990 a large turtle from the same locality and horizon. Methods. Remains of basicranium (basioccipital and basisphenoid), fragments of both quadrates, left opisthotic, a lower jaw, cervical vertebrae, one caudal vertebra, appendicular skeleton, a partial carapace and one almost complete plastron are preserved in MACN Pv M2. In order to explore the phylogenetic relationships of MACN Pv M2, this specimen was included in a data matrix built up by 48 characters and 17 taxa. One fragmentary costal plate was sampled for histological analysis. The bone microstructure of the thin sections was studied under light microscopy using normal and polarized lights. Results. The preliminary phylogenetic analysis suggests that MACN Pv M2 is nested in a clade also including Phrynops hilarii + Mesoclemmys nasuta + long-necked chelids. The pelvic girdle attached by suture to the shell in MACN Pv M2 and the synapomorphic characters such as splenial bone in the lower jaw, ilium extending over the eight costal and anterior margin of the suprapygal bones allow us to assign this specimen to Pleurodira Chelidae. The microanatomy of MACN Pv M2 shows a diploe structure as in other turtles. The internal cortex is equal or slowly thinner than the external one, and the cancellous bone occupy the main proportion (50-60%). The external cortex is composed of structural fibre bundles that extend parallel to the external surface and orient longitudinally and transversally to the progression of the elements. The cancellous bone is mostly well developed. The internal cortex consists of parallel-fibred bone that locally can grade into lamellar bone. Discussion. The unique combination of plesiomorphies (such as lateral mesoplastra, area articularis mandibularis concave, a short midline epiplastral suture, an anterior peripherals bones shorter than posterior ones) and autapomorphies (such as both rami of the lower jaw fused, extremely wide anterior plastral lobe, and a slightly epiplastral notch) recovered in this phylogenetic analysis allow to assigned MACN Pv M2 as a new species of short-necked chelid taxa. The histology of MACN Pv M2 shows features that suggest adaptation to the aquatic lifestyle (i.e., well vascularized external cortex, the vascularization of the internal cortex composed of scattered vascular canals and primary osteons of longitudinally orientation).

scholarly journals A new short-necked chelid turtle from the Loncoche Formation (Late Campanian- Early Maastrichtian) Mendoza province, Argentina: Macro, microanatomy, and preliminary phylogenetic relationships

2015 ◽  
Author(s):  
Marcelo de la Fuente ◽  
Ignacio Maniel ◽  
Juan Marcos Jannello ◽  
Juliana Sterli ◽  
Bernardo González Riga ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Cancellous Bone ◽  
Phylogenetic Relationships ◽  
Cervical Vertebrae ◽  
Data Matrix ◽  
Appendicular Skeleton ◽  
Thin Sections ◽  
Lower Jaw ◽  
A New Species ◽  
Preliminary Phylogenetic Analysis

Background. The lower section of the Loncoche Formation (Late Campanian-Early Maastrichtian) outcropping at Ranquil-Có locality (Mendoza province, Argentina) has yielded a rich assemblage of vertebrates that was studied in 1995 by Gonzalez Riga. According to this author these vertebrate remains were found in a tidal paleoenvironment, resulting from transportation, mixing and deposition of continental remains mixed with those from near costal environments. Previously to these findings Jose F. Bonaparte recovered in 1990 a large turtle from the same locality and horizon. Methods. Remains of basicranium (basioccipital and basisphenoid), fragments of both quadrates, left opisthotic, a lower jaw, cervical vertebrae, one caudal vertebra, appendicular skeleton, a partial carapace and one almost complete plastron are preserved in MACN Pv M2. In order to explore the phylogenetic relationships of MACN Pv M2, this specimen was included in a data matrix built up by 48 characters and 17 taxa. One fragmentary costal plate was sampled for histological analysis. The bone microstructure of the thin sections was studied under light microscopy using normal and polarized lights. Results. The preliminary phylogenetic analysis suggests that MACN Pv M2 is nested in a clade also including Phrynops hilarii + Mesoclemmys nasuta + long-necked chelids. The pelvic girdle attached by suture to the shell in MACN Pv M2 and the synapomorphic characters such as splenial bone in the lower jaw, ilium extending over the eight costal and anterior margin of the suprapygal bones allow us to assign this specimen to Pleurodira Chelidae. The microanatomy of MACN Pv M2 shows a diploe structure as in other turtles. The internal cortex is equal or slowly thinner than the external one, and the cancellous bone occupy the main proportion (50-60%). The external cortex is composed of structural fibre bundles that extend parallel to the external surface and orient longitudinally and transversally to the progression of the elements. The cancellous bone is mostly well developed. The internal cortex consists of parallel-fibred bone that locally can grade into lamellar bone. Discussion. The unique combination of plesiomorphies (such as lateral mesoplastra, area articularis mandibularis concave, a short midline epiplastral suture, an anterior peripherals bones shorter than posterior ones) and autapomorphies (such as both rami of the lower jaw fused, extremely wide anterior plastral lobe, and a slightly epiplastral notch) recovered in this phylogenetic analysis allow to assigned MACN Pv M2 as a new species of short-necked chelid taxa. The histology of MACN Pv M2 shows features that suggest adaptation to the aquatic lifestyle (i.e., well vascularized external cortex, the vascularization of the internal cortex composed of scattered vascular canals and primary osteons of longitudinally orientation).

scholarly journals Taxonomic revision and phylogenetic relationships of Dasyloricaria Isbrücker & Nijssen, 1979 (Siluriformes: Loricariidae), with description of a new species

2016 ◽  
Vol 14 (1) ◽  
Author(s):  
Alejandro Londoño-Burbano ◽  
Roberto E. Reis
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Phylogenetic Relationships ◽  
Taxonomic Revision ◽  
Sister Group ◽  
Valid Species ◽  
Maracaibo Basin ◽  
New Synonyms ◽  
Branchial Arches ◽  
A New Species

ABSTRACT A taxonomic revision and phylogenetic analysis were completed for Dasyloricaria . The genus includes three valid species: D . filamentosa and D . latiura previously included in the genus, and a new species described herein. Dasyloricaria have a restricted trans-Andean distribution, with D . filamentosa occurring at the lower and middle Magdalena, lower Cauca, and Sinu in Colombia, and lago Maracaibo basin in Colombia and Venezuela; D . latiura in the Atrato and the Tuyra basins in Colombia and Panama, respectively; and the new species in the upper and middle Magdalena basin in Colombia. New synonyms for D . filamentosa and D . latiura are proposed, and a lectotype is designated for the latter. Dasyloricaria is herein recognized as monophyletic, with D . filamentosa as the sister group of D . latiura , and the new speciesas sister to that clade. Spatuloricaria is hypothesized to be the sister group of Dasyloricaria based on synapomorphies of the neurocranium, branchial arches and external morphology features. The subtribe Rineloricariina was partially corroborated through the phylogenetic analysis. An identification key for the species of Dasyloricaria is provided.

Phylogeny of the Mycetophiliformia, with proposal of the subfamilies  Heterotrichinae, Ohakuneinae, and Chiletrichinae for the Rangomaramidae (Diptera, Bibionomorpha)

Zootaxa ◽  
2007 ◽  
Vol 1535 (1) ◽  
pp. 1-92 ◽  
Author(s):  
DALTON DE SOUZA AMORIM ◽  
EIRIK RINDAL
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Sister Group ◽  
Data Matrix ◽  
Southern Brazil ◽  
The Family ◽  
First Time ◽  
A New Species ◽  
Transformation Series

A phylogenetic analysis of the Mycetophiliformia (= Sciaroidea) was performed to determine the relationships among its families and to place the following genera of uncertain position in the system: Heterotricha, Ohakunea, Colonomyia, Freemanomyia, Rhynchoheterotricha, Chiletricha, Afrotricha, Anisotricha, Kenyatricha, Nepaletricha, Sciarosoma, Sciaropota, Insulatricha, Cabamofa, Rogambara, and Starkomyia. Eratomyia n. gen. is described based on a new species from Ecuador. Colonomyia brasiliana sp.n. and Colonomyia freemani sp.n. are described respectively from southern Brazil and Chile. The male of Cabamofa mira Jaschhof is described for the first time. A total of 64 terminal taxa and 137 transformation series (with 202 characters) were included in the data matrix, with a number of new features from thoracic morphology. Willi Hennig’s 1973 system for the higher Bibionomorpha was adopted using the name Mycetophiliformia for the Sciaroidea. The Mycetophiliformia are monophyletic. The family Cecidomyiidae appears as the sister group of the remaining Mycetophiliformia, followed by the Sciaridae. In the preferred topology, the Rangomaramidae appear as the group sister of a clade consisting of (Ditomyiidae + Bolitophilidae + Diadocidiidae + Keroplatidae) and of (Lygistorrhinidae + Mycetophilidae). The topology within the Rangomaramidae is (Chiletrichinae subfam. n. (Heterotrichinae subfam. n. ((Rangomaraminae + Ohakuneinae subfam. n.))). The Chiletrichinae include the genera Kenyatricha, Rhynchoheterotricha, Insulatricha, Chiletricha, and Eratomyia n. gen. Heterotrichinae and Rangomaraminae are monotypic. The subfamily Ohakuneinae includes Ohakunea, Colonomyia, Cabamofa, and Rogambara. The positions of Freemanomyia, Loicia, Taxicnemis, Sciaropota, Starkomyia, Anisotricha, Nepaletricha, and Sciarosoma are considered. Afrotricha might belong to the Sciaridae. The similarities used by many authors to gather the Sciaridae and Mycetophilidae in a clade are shown to be a combination of plesiomorphies and homoplasies.

A new species of the genus Lucasioides Kwon, 1993 (Isopoda, Oniscidea, Agnaridae) from Siberia, Russia

Zootaxa ◽  
2021 ◽  
Vol 4903 (1) ◽  
pp. 140-150
Author(s):  
KONSTANTIN B. GONGALSKY ◽  
PAVEL S. NEFEDIEV ◽  
ILYA S. TURBANOV
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
First Record ◽  
Morphological Characters ◽  
Molecular Data ◽  
Altai Mountains ◽  
The Family ◽  
Southwestern Siberia ◽  
A New Species ◽  
Preliminary Phylogenetic Analysis

A new species of the family Agnaridae, Lucasioides altaicus sp. nov., is described from the Altai Mountains, southwestern Siberia, based both on morphological characters and molecular data. This species is the first record of Lucasioides from Russia, whose location is the northernmost habitat of terrestrial isopods in indigenous habitats presently known to Eurasia. The diagnostic characters of the new species and a preliminary phylogenetic analysis within Agnaridae are provided. 

scholarly journals Reevaluation of the largest published morphological data matrix for phylogenetic analysis of Paleozoic limbed vertebrates

2015 ◽  
Author(s):  
David Marjanović ◽  
Michel Laurin
Keyword(s):  
Phylogenetic Analysis ◽  
Data Matrix ◽  
Morphological Data ◽  
Lower Jaw ◽  
12 Steps ◽  
The Matrix ◽  
One Step ◽  
The Difference ◽  
Character Complexes ◽  
The Many

The largest data matrix for phylogeny of early limbed vertebrates (Ruta M, Coates MI. 2007. J. Syst. Palaeont. 5:69–122) has supported controversial hypotheses; e.g., it has recovered Seymouriamorpha, Diadectomorpha and (in some trees) Caudata as paraphyletic and found the “temnospondyl hypothesis” on the origin of Lissamphibia (TH) to be one step more parsimonious than the “lepospondyl hypothesis” (LH). Scrutiny of the matrix reveals thousands of suboptimal scores (many clearly due to typographic and similar errors) as well as logically linked (redundant) characters, characters with only one described state, and even cases where taxa were scored after presumed relatives. Moreover, all characters – even obviously continuous ones – were unordered, effects of ontogeny were not sufficiently taken into account, and the authors mostly excluded data published after 2001, even their own. Our revised version – we document and justify all changes – yields much longer trees with a different topology, e.g. monophyletic Caudata, Diadectomorpha and (sometimes) Seymouriamorpha, Ichthyostega more rootward than Acanthostega, Anthracosauria more rootward than Temnospondyli, and the LH, which is 10 steps more parsimonious than the TH and 15 more than the “polyphyly hypothesis” (PH). Bootstrap values, though, are low, and few of the topologies are statistically distinguishable. For another set of analyses, we added 48 OTUs to the original 102. This destabilizes parts of the tree, e.g. the relationships of Anthracosauria and Temnospondyli. However, many of the added taxa have a fully resolved position or nearly so; this concerns the well-known Chroniosaurus (sister to a clade containing Solenodonsaurus, Seymouriamorpha, Diadectomorpha, Amniota and Amphibia), but also isolated lower-jaw material from the Devonian and Carboniferous. Despite the addition of Gerobatrachus, Micropholis and Tungussogyrinus and the extremely peramorphic salamander Chelotriton, the difference between LH and TH only shrinks to 9 steps, that between LH and PH to 13 steps. The “lepospondyl” Brachydectes is neither found as sister to Lissamphibia nor in the “microsaur” grade. Bootstrap values plummet, though, and all three hypotheses become statistically indistinguishable at p = 0.05. We then duplicated all analyses after coding all losses of bones as irreversible. Anthracosauria is then consistently placed more rootward than Temnospondyli; given the original taxon sample, the LH is 12 steps shorter than the “temnospondyl hypothesis” and 17 steps shorter than the PH, while the expanded taxon sample makes the LH 10 steps shorter than the TH and only 12 steps shorter than the PH. More robust results could likely be obtained by adding the many characters used in other analyses or discussed in the literature. We discuss phylogeny, approaches to coding, and certain character complexes, in particular the supposed middle ear of temnospondyls.

A New Species of Physeterostemon (Melastomataceae) from Bahia, Brazil, with Notes on the Phylogeny of the Genus

2009 ◽  
Vol 34 (2) ◽  
pp. 324-329 ◽  
Author(s):  
André M. Amorim ◽  
Renato Goldenberg ◽  
Fabián A. Michelangeli
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Dna Sequence ◽  
Atlantic Forest ◽  
Phylogenetic Relationships ◽  
Sequence Data ◽  
Sensu Stricto ◽  
The Other ◽  
Dna Sequence Data ◽  
A New Species

Physeterostemon thomasii is described from the southern Bahian Atlantic forest of Brazil. It differs from the other two species of the genus by the paleaceous trichomes on young stems and petioles, and by the strongly bullate/foveolate leaves. A phylogenetic analysis with all three species, based on rbcL and ndhF DNA sequence data, showed that Physeterostemon forms a monophyletic group, sister to Eriocnema fulva, and this clade is placed in a polytomy at the base of the tribe Miconieae sensu stricto. However, there is no resolution within Physeterostemon, thus the phylogenetic relationships of the three species cannot be established.

A phylogenetic analysis of Stenostomum and its neotropical congeners, with a description of a new species from the Peruvian Amazon Basin

2011 ◽  
Vol 25 (2) ◽  
pp. 155 ◽  
Author(s):  
Cristina Damborenea ◽  
Francisco Brusa ◽  
Io Almagro ◽  
Carolina Noreña
Keyword(s):  
Phylogenetic Analysis ◽  
Morphological Study ◽  
Amazon Basin ◽  
Morphological Characteristics ◽  
Morphological Data ◽  
Freshwater Species ◽  
Peruvian Amazon ◽  
Pharyngeal Constriction ◽  
A New Species ◽  
Preliminary Phylogenetic Analysis

This study reports Peruvian freshwater species of Stenostomum (Catenulida) from the upper Yurúa River of the Amazon Basin. A total of 11 species were found. One of them, Stenostomum ashanika, sp. nov., is described. It can be distinguished by: a pre-pharyngeal constriction; a small cauda; a small, rounded, mobile and ventrally directed pharynx; and a tri-radiate mouth. The remaining 10 species are reviewed and illustrated; eight are first records for Peru. A preliminary phylogenetic analysis of neotropical stenostomid species based on morphological data is undertaken, including all Rhynchoscolex, Stenostomum and Myostenostomum species described for the area. The Rhynchoscolex species are basal and paraphyletic; the species of Myostenostomum are monophyletic, within the Stenostomum clade, supported by the presence of a muscular gizzard in the anterior region of the intestine. Ciliated pits and rhabdoids are synapomorphies of the Stenostomum + Myostenostomum clade. This is the first morphological study of the relationships between stenostomid species. The most relevant characters in the phylogenetic analysis are those related to cerebral brain lobes. The results also show that many of the morphological characteristics of the species under study are poorly known and should be studied in more depth.

A new early dinosaur (Sauropodomorpha) from the Caturrita Formation (Late Triassic), Paran Basin, Brazil

Zootaxa ◽  
2004 ◽  
Vol 690 (1) ◽  
pp. 1 ◽  
Author(s):  
LUCIANO A. LEAL ◽  
SERGIO A.K. AZEVEDO ◽  
ALEXANDER W.A. KELLNER ◽  
ÁTILA A.S. DA ROSA
Keyword(s):  
Phylogenetic Analysis ◽  
Lateral Surface ◽  
Late Triassic ◽  
Clear Picture ◽  
Southern Brazil ◽  
Red Beds ◽  
Lower Jaw ◽  
Preliminary Phylogenetic Analysis ◽  
Comprehensive Studies

A new early dinosaur, Unaysaurus tolentinoi gen. et sp. nov., from the continental Late Triassic red beds of the Caturrita Formation (Carnian-Norian, c. 225 million years old) of southern Brazil is described. U. tolentinoi is represented by a semi-articulated skeleton comprising an almost complete skull, lower jaw and postcranial elements. It differs from all other dinosaurs by several cranial (e.g. developed laterodorsally oriented process formed by frontal and parietal; deep ventral depression on the basisphenoid) and postcranial (presence of a conspicuous blunt ridge running on the lateral surface of the deltopectoral crest of humerus) characters. Unaysaurus represents the first prosauropod grade dinosaur from Brazil and a preliminary phylogenetic analysis indicates it to be closely related to the European Plateosaurus (Plateosauridae). The relationships of the Prosauropoda , however, are still controversial and more comprehensive studies are needed before a clear picture of the evolution and paleobiogeographic distributions of these dinosaurs can be presented.

Nothotrichocera Alexander (Diptera : Trichoceridae): new species, redescriptions and phylogenetic relationships within the genus

2001 ◽  
Vol 15 (2) ◽  
pp. 205 ◽  
Author(s):  
Ewa Krzeminska
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Phylogenetic Relationships ◽  
Species Groups ◽  
A New Species ◽  
Eleven Species ◽  
Geographically Isolated

Nothotrichocera antarctica (Edwards), Nothotrichocera tonnoiri Alexander and Nothotrichocera tasmanica Alexander are redescribed and a new species of the cingulata-group, N. collessi, sp. nov., is described. The eleven species of Nothotrichocera belong in four well-defined groups of species, which have evolved in geographically isolated, circum-Antarctic regions. The unique positions of N. tonnoiri and N. tasmanica are stressed. A key to the species-groups is given and a phylogenetic analysis of the genus is presented.

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.

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