scholarly journals Phylogenetic relationships among extinct and extant turtles: the position of Pleurodira and the effects of the fossils on rooting crown-group turtles

2010 ◽  
Vol 79 (3) ◽  
pp. 93-106 ◽  
Author(s):  
Juliana Sterli
Keyword(s):  
Phylogenetic Relationships ◽  
Sister Group ◽  
Molecular Data ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Separate Analysis ◽  
Crown Group ◽  
Rapid Radiation ◽  
Present Contribution ◽  
Origin And Evolution

The origin and evolution of the crown-group of turtles (Cryptodira + Pleurodira) is one of the most interesting topics in turtle evolution, second perhaps only to the phylogenetic position of turtles among amniotes. The present contribution focuses on the former problem, exploring the phylogenetic relationships of extant and extinct turtles based on the most comprehensive phylogenetic dataset of morphological and molecular data analyzed to date. Parsimony analyses were conducted for different partitions of data (molecular and morphological) and for the combined dataset. In the present analysis, separate analyses of the molecular data always retrieve Pleurodira allied to Trionychia. Separate analysis of the morphological dataset, by contrast, depicts a more traditional arrangement of taxa, with Pleurodira as the sister group of Cryptodira, being Chelonioidea the most basal cryptodiran clade. The simultaneous analysis of all available data retrieves all major extant clades as monophyletic, except for Cryptodira given that Pleurodira is retrieved as the sister group of Trionychia. The paraphyly of Cryptodira is an unorthodox result, and is mainly caused by the combination of two factors. First, the molecular signal allies Pleurodira and Trionychia. Second, the morphological data with extinct taxa locates the position of the root of crown-group Testudines in the branch leading to Chelonioidea. This study highlights major but poorly explored topics of turtle evolution: the alternate position of Pleurodira and the root of crown turtles. The diversification of crown turtles is characterized by the presence of long external branches and short internal branches (with low support for the internal nodes separating the major clades of crown turtles), suggesting a rapid radiation of this clade. This rapid radiation is also supported by the fossil record, because soon after the appearance of the oldest crown-group turtles (Middle-Late Jurassic of Asia) the number and diversity of turtles increases remarkably. This evolutionary scenario of a rapid diversification of modern turtles into the major modern lineages is likely the reason for the difficulty in determining the interrelationships and the position of the root of crown-group turtles.

The origin and early diversification of birds

Paleobiology ◽  
1986 ◽  
Vol 12 (4) ◽  
pp. 383-399 ◽  
Author(s):  
Joel Cracraft
Keyword(s):  
Phylogenetic Relationships ◽  
Cladistic Analysis ◽  
Sister Group ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Pectoral Girdle ◽  
Avian Evolution ◽  
Theropod Dinosaurs ◽  
Early Diversification ◽  
Time Of Origin

Numerical cladistic analysis of 73 cranial and postcranial characters has resulted in a highly corroborated hypothesis describing the phylogenetic pattern of early avian evolution. Using “non-avian theropod” dinosaurs as a comparative outgroup and root for the tree, the analysis confirmed Archaeopteryx to be the sister-group of all remaining avian taxa, or Ornithurae. This latter taxon is subdivided into two lineages, the Hesperornithiformes and the Carinatae. The carinates, in turn, were also resolved into two sister-groups, the Ichthyornithiformes and the modern birds, or Neornithes. This paper provides morphological data corroborating the divergence of the two basal clades of the Neornithes: the Palaeognathae (tinamous and ratites) and Neognathae (all other modern birds). The phylogenetic relationships of four important Cretaceous taxa were also investigated, but these fossil taxa were too fragmentary to determine their phylogenetic position unambiguously. Alexornis and Ambiortus are both carinates, but their relationships cannot be resolved in greater detail. The relationships of the Enantiornithes may lie within the Carinatae or these two taxa may be sister-groups. Gobipteryx is a neornithine and possibly the sister-group of the Palaeognathae.This analysis indicates that major patterns of morphological change took place at the time of origin of the ancestors of the Ornithurae and the Carinatae. Ornithurine innovations included major changes throughout the skeleton, whereas those of the carinates, while substantial, were primarily restricted to the pectoral girdle and forelimb. The phylogenetic results, in conjunction with the known ages of fossil taxa, indicate that the early lineages of birds very likely arose in the Jurassic. The early cladistic events within the neornithine lineage are also more ancient than generally recognized, and may well extend back to the early Cretaceous.

scholarly journals Phylogenetic relationships of heteroscleromorph demosponges and the affinity of the genus Myceliospongia (Demospongiae incertae sedis)

2019 ◽  
Author(s):  
Dennis V. Lavrov ◽  
Manuel Maldonado ◽  
Thierry Perez ◽  
Christine Morrow
Keyword(s):  
Molecular Clock ◽  
Phylogenetic Relationships ◽  
Sister Group ◽  
Molecular Data ◽  
Sensu Stricto ◽  
Rrna Genes ◽  
Phylogenetic Position ◽  
Incertae Sedis ◽  
Middle Paleozoic ◽  
Clade 1

AbstractClass Demospongiae – the largest in the phylum Porifera (Sponges) – encompasses 7,581 accepted species across the three recognized subclasses: Keratosa, Verongimorpha, and Heteroscleromorpha. The latter subclass contains the majority of demosponge species and was previously subdivided into subclasses Heteroscleromorpha sensu stricto and Haploscleromorpha. The current classification of demosponges is the result of nearly three decades of molecular studies that culminated in a formal proposal of a revised taxonomy (Morrow and Cardenas, 2015). However, because most of the molecular work utilized partial sequences of nuclear rRNA genes, this classification scheme needs to be tested by additional molecular markers. Here we used sequences and gene order data from complete or nearly complete mitochondrial genomes of 117 demosponges (including 60 new sequences determined for this study and 6 assembled from public sources) and three additional partial mt-genomes to test the phylogenetic relationships within demosponges in general and Heteroscleromorpha sensu stricto in particular. We also investigated the phylogenetic position of Myceliospongia araneosa – a highly unusual demosponge without spicules and spongin fibers, currently classified as Demospongiae incertae sedis.Our results support the sub-class relationship within demosponges and reveal four main clades in Heteroscleromorpha sensu stricto: Clade 1 composed of Spongillida, Sphaerocladina, and Scopalinida; Clade 2 composed of Axinellida, Biemnida, Bubarida; Clade 3 composed of Tetractinellida and “Rhizomorina” lithistids; and Clade 4 composed of Agelasida, Polymastida, Clionaida, Suberitida, Poecilosclerida, and Tethyida. The four clades appear to be natural lineages that unite previously defined taxonomic orders. Therefore, if those clades are to be systematically interpreted, they will have the rank of superorders (hence S1-S4). We inferred the following relationships among the newly defined clades: (S1(S2(S3+S4))). Analysis of molecular data from Myceliospongia araneosa – first from this species/genus – placed it in S3 as a sister group to Microscleroderma sp. and Leiodermatium sp. (“Rhizomorina”).Molecular clock analysis indicated that the origin of the Heteroscleromorpha sensu stricto as well as the basal split in this group between S1 and the rest of the superorder go back to Cambrian, while the divergences among the three other superorders occurred in Ordovician (with the 95% standard variation from Late Cambrian to Early Silurian). Furthermore most of the proposed orders within Heteroscleromorpha appear to have middle Paleozoic origin, while crown groups within order date mostly to Paleozoic to Mesozoic transition. We propose that these molecular clock estimates can be used to readjust ranks for some of the higher taxa within Heteroscleromorpha.In addition to phylogenetic information, we found several unusual mtgenomic features among the sampled species, broadening our understanding of mitochondrial genome evolution in this group and animals in general. In particular, we found mitochondrial introns within cox2 (first in animals) and rnl (first in sponges).

scholarly journals Redescription of the skull of the Australian flatback sea turtle, Natator depressus, provides new morphological evidence for phylogenetic relationships among sea turtles (Chelonioidea)

2020 ◽  
Author(s):  
Ray M Chatterji ◽  
Mark N Hutchinson ◽  
Marc E H Jones
Keyword(s):  
Phylogenetic Relationships ◽  
Sea Turtles ◽  
Sea Turtle ◽  
Molecular Data ◽  
Morphological Data ◽  
Morphological Evidence ◽  
Molecular Evidence ◽  
Crown Group ◽  
Extant Species ◽  
Natator Depressus

Abstract Chelonioidea (sea turtles) are a group where available morphological evidence for crown-group relationships are incongruent with those established using molecular data. However, morphological surveys of crown-group taxa tend to focus on a recurring subset of the extant species. The Australian flatback sea turtle, Natator depressus, is often excluded from comparisons and it is the most poorly known of the seven extant species of Chelonioidea. Previous descriptions of its skull morphology are limited and conflict. Here we describe three skulls of adult N. depressus and re-examine the phylogenetic relationships according to morphological character data. Using X-ray micro Computed Tomography we describe internal structures of the braincase and identify new phylogenetically informative characters not previously reported. Phylogenetic analysis using a Bayesian approach strongly supports a sister-group relationship between Chelonia mydas and N. depressus, a topology that was not supported by previous analyses of morphological data but one that matches the topology supported by analysis of molecular data. Our results highlight the general need to sample the morphological anatomy of crown-group taxa more thoroughly before concluding that morphological and molecular evidence are incongruous.

scholarly journals The Immature Stages, Biology, and Phylogenetic Relationships of Rotunda rotundapex (Lepidoptera: Bombycidae)

2019 ◽  
Vol 19 (2) ◽  
Author(s):  
Rung-Juen Lin ◽  
Michael F Braby ◽  
Yu-Feng Hsu
Keyword(s):  
Phylogenetic Relationships ◽  
Host Plants ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Immature Stages ◽  
Systematic Classification ◽  
Separate Genus ◽  
Young Leaves ◽  
Segment 8 ◽  
First Time

Abstract The life history, morphology, and biology of the immature stages and phylogenetic relationships of Rotunda rotundapex (Miyata & Kishida, 1990) are described and illustrated for the first time. The species is univoltine: eggs hatch in spring (March or April) and the life cycle from egg to adult is completed in about 3 wk, with larvae developing rapidly on young leaves of the host plants, Morus australis and to a lesser extent Broussonetia monoica (Moraceae), and adults emerging in April–May. Eggs are laid in clusters on twigs of the host plant, are covered by scales during female oviposition, and remain in diapause for the remainder of the year (i.e., for 10–11 mo). Larvae (all instars) are unique among the Bombycidae in that they lack a horn on abdominal segment 8. A strongly supported molecular phylogeny based on six genes (5.0 Kbp: COI, EF-1α, RpS5, CAD, GAPDH, and wgl) representing seven genera of Bombycinae from the Old World revealed that Rotunda is a distinct monotypic lineage sister to Bombyx. This phylogenetic position, together with morphological data of the immature stages (egg and larval chaetotaxy), supports the current systematic classification in which the species rotundapex has been placed in a separate genus (Rotunda) from Bombyx in which it was previously classified.

First plesiosaur remains from the lower Cretaceous of the Neuquén Basin, Argentina

2003 ◽  
Vol 77 (4) ◽  
pp. 784-789 ◽  
Author(s):  
Dario G. Lazo ◽  
Marcela Cichowolski
Keyword(s):  
Lower Cretaceous ◽  
Sister Group ◽  
Monophyletic Group ◽  
Phylogenetic Position ◽  
Crown Group ◽  
Marine Reptiles ◽  
Stem Group ◽  
Neuquen Basin ◽  
Neuquén Basin

Plesiosaurs constitute a monophyletic group whose stratigraphical range is uppermost Triassic to uppermost Cretaceous (Brown, 1981). They were large predatory marine reptiles, highly adapted for submarine locomotion, with powerful paddle-like limbs and heavily reinforced limb girdles (Saint-Seine, 1955; Romer, 1966; Carroll, 1988; Benton, 1990). The Plesiosauria clade belongs to the Sauropterygia, which has recently been hypothesized as the sister-group of the Ichthyosauria. Together with that clade they form the Euryapsida (Caldwell, 1997). The Sauropterygia can be subdivided into relatively plesiomorphic stem-group taxa from the Triassic (Placodonts, Nothosauroids, and Pistosauroids), and the obligatorily marine crown-group Plesiosauria (Rieppel, 1999). Plesiosaurs are traditionally divided into two superfamilies: Plesiosauroidea, with usually small heads and long necks; and Pliosauroidea, with larger heads and shorter necks (Welles, 1943; Persson, 1963; Brown, 1981). Plesiosauroidea contains three families: Plesiosauridae, Cryptoclididae, and Elasmosauridae (Brown, 1981; Brown and Cruickshank, 1994). The validity of the Polycotylidae Cope, 1869, has long been questioned and its phylogenetic position among Plesiosauria debated, as many consider it to be related to the Pliosauridae or to be a sister-group of the Elasmosauridae (Sato and Storrs, 2000; O'Keefe, 2001).

Phylogenetic relationships of the subfamily Pyrgulinae (Gastropoda: Caenogastropoda: Hydrobiidae) with emphasis on the genus Dianella Gude, 1913

Zootaxa ◽  
2005 ◽  
Vol 891 (1) ◽  
pp. 1 ◽  
Author(s):  
Magdalena Szarowska ◽  
Andrzej Falniowski ◽  
FRANK Riedel ◽  
Thomas Wilke
Keyword(s):  
Type Species ◽  
Sister Group ◽  
Molecular Data ◽  
Character Evolution ◽  
Phylogenetic Position ◽  
Sister Group Relationship ◽  
Data Sets ◽  
Sequencing Data ◽  
The Family ◽  
Anatomical Characters

The phylogenetic position of the subfamily Pyrgulinae within the superfamily Rissooidea has been discussed very controversially. Different data sets not only led to different evolutionary scenarios but also to different systematic classifications of the taxon. The present study uses detailed anatomical data for two pyrgulinid taxa, the type species of the subfamily, Pyrgula annulata (Linnaeus, 1767), and the type species of the little known genus Dianella, D. thiesseana (Kobelt, 1878), as well as DNA sequencing data of three gene fragments from representatives of eight rissooidean families to A) infer the phylogenetic position of Pyrgulinae with emphasis on its relationships within the family Hydrobiidae, B) to study the degree of concordance between anatomyand DNAbased phylogenies and C) to trace the evolution of anatomical characters along a multi-gene molecular phylogeny to find the anatomical characters that might be informative for future cladistic analyses. Both anatomical and molecular data sets indicate either a very close or even sister-group relationship of Pyrgulinae and Hydrobiinae. However, there are major conflicts between the two data sets on and above the family level. Notably, Hydrobiidae is not monophyletic in the anatomical analysis. The reconstruction of anatomical character evolution indicates that many of the characters on which the European hydrobioid taxonomy is primarily based upon are problematic. The inability to clearly separate some hydrobiids from other distinct families based on those characters might explain why until only a few years ago, "Hydrobiidae" was a collecting box for numerous rissooidean taxa (mostly species with shells small and lacking any characteristic features). The present study not only stresses the need for comprehensive molecular studies of rissooidean taxa, it also demonstrates that much of the problems surrounding anatomical analyses in rissooidean taxa are due to the lack of comprehensive data for many representatives. In order to aid future comparativeanatomical studies and a better understanding of character evolution in the species-rich family Hydrobiidae, detailed anatomical descriptions for P. annulata and D. thiesseana are provided.Key words: Pyrgulinae, Pyrgula, Dianella, Hydrobiidae, phylogeny, DNA, anatomy, Greece

scholarly journals Cretaceous origin and repeated tertiary diversification of the redefined butterflies

2011 ◽  
Vol 279 (1731) ◽  
pp. 1093-1099 ◽  
Author(s):  
Maria Heikkilä ◽  
Lauri Kaila ◽  
Marko Mutanen ◽  
Carlos Peña ◽  
Niklas Wahlberg
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Evolutionary History ◽  
Sister Group ◽  
Morphological Characters ◽  
Molecular Data ◽  
Bayesian Approaches ◽  
The Family ◽  
Family Level ◽  
Morphological And Molecular Data

Although the taxonomy of the ca 18 000 species of butterflies and skippers is well known, the family-level relationships are still debated. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the superfamilies Papilionoidea, Hesperioidea and Hedyloidea to date based on morphological and molecular data. We reconstructed their phylogenetic relationships using parsimony and Bayesian approaches. We estimated times and rates of diversification along lineages in order to reconstruct their evolutionary history. Our results suggest that the butterflies, as traditionally understood, are paraphyletic, with Papilionidae being the sister-group to Hesperioidea, Hedyloidea and all other butterflies. Hence, the families in the current three superfamilies should be placed in a single superfamily Papilionoidea. In addition, we find that Hedylidae is sister to Hesperiidae, and this novel relationship is supported by two morphological characters. The families diverged in the Early Cretaceous but diversified after the Cretaceous–Palaeogene event. The diversification of butterflies is characterized by a slow speciation rate in the lineage leading to Baronia brevicornis , a period of stasis by the skippers after divergence and a burst of diversification in the lineages leading to Nymphalidae, Riodinidae and Lycaenidae.

Phylogenetic analysis of the Neotropical Pristimantis leptolophus species group (Anura: Craugastoridae): molecular approach and description of a new polymorphic species 

Zootaxa ◽  
2017 ◽  
Vol 4242 (2) ◽  
pp. 313
Author(s):  
MAURICIO RIVERA-CORREA ◽  
CARLOS JIMÉNEZ-RIVILLAS ◽  
JUAN M. DAZA
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Reconstruction ◽  
Morphological Diversity ◽  
Molecular Data ◽  
Species Group ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Molecular Evidence ◽  
Polymorphic Species ◽  
Species Groups

Pristimantis, distributed throughout the New World tropics, is the most speciose vertebrate genus. Pristimantis presents an enormous morphological diversity and is currently divided into several demonstrably non-monophyletic phenetic species groups. With the purpose of increasing our understanding of Pristimantis systematics, we present the first phylogenetic analysis using molecular evidence to test the monophyly and infer evolutionary relationships within the Pristimantis leptolophus group, an endemic group of frogs from the highlands of the Colombian Andes. Our phylogenetic reconstruction recovers the group as monophyletic with high support, indicating general concordance between molecular data and morphological data. In addition, we describe a new polymorphic species lacking conspicuous tubercles, a regular attribute among species of the P. leptolophus species group and endemic from the Páramo de Sonsón complex (Antioquia, Colombia). The phylogenetic position of the new species is inferred and other systematic implications in the light of our results are discussed. 

Phylogenetic relationships and classification of the Malagasy pseudoxyrhophiine snake genera Geodipsas and Compsophis based on morphological and molecular data

Zootaxa ◽  
2007 ◽  
Vol 1517 (1) ◽  
pp. 53-62 ◽  
Author(s):  
FRANK GLAW ◽  
ZOLTÁN T. NAGY ◽  
MIGUEL VENCES
Keyword(s):  
Dna Sequences ◽  
Phylogenetic Relationships ◽  
Close Relationships ◽  
Original Description ◽  
Molecular Data ◽  
Morphological Data ◽  
Molecular Phylogenetic ◽  
Species Groups ◽  
Morphological And Molecular Data

Based on a specimen found at Montagne d'Ambre in northern Madagascar morphologically agreeing with Compsophis albiventris Mocquard, 1894, we report on the rediscovery of this enigmatic snake genus and species and its molecular phylogenetic relationships. Compsophis albiventris, considered to be the only representative of its genus and unreported since its original description, bears strong morphological similarities to species of Geodipsas Boulenger, 1896. A molecular phylogeny based on DNA sequences of three mitochondrial and nuclear genes (complete cytochrome b, fragments of 16S rRNA and c-mos) in Compsophis albiventris and three Geodipsas species corroborated close relationships between C. albiventris and Geodipsas boulengeri, and showed that the genera Compsophis and Geodipsas together form a monophyletic unit. Despite the general similarities, morphological data and chromatic features support the existence of two species groups, corresponding to Compsophis and Geodipsas. We consequently consider Geodipsas as a subgenus of Compsophis and transfer all species currently in Geodipsas into the genus Compsophis.

The greenhouse thrips, Heliothrips haemorrhoidalis, and its generic relationships within the subfamily Panchaetothripinae (Thysanoptera: Thripidae)

2001 ◽  
Vol 32 (2) ◽  
pp. 205-216 ◽  
Author(s):  
John W.H. Trueman ◽  
Rita Marullo ◽  
Laurence A. Mound
Keyword(s):  
Sister Group ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Sister Group Relationship ◽  
Pest Species ◽  
Data Set ◽  
Weak Support ◽  
Heliothrips Haemorrhoidalis ◽  
Generic Relationships

AbstractThe subfamily Panchaetothripinae, comprising 35 genera and 98 species, includes several pest species of which the most notorious is the greenhouse thrips, Heliothrips haemorrhoidalis. In an attempt to establish the sister-group of Heliothrips, the relationships of this genus to 31 of the other genera in the subfamily were examined cladistically, using 35 parsimony-informative morphological characters. The analysis indicated that there was no support for two of the three tribes into which this subfamily is customarily arranged, the Monilothripini and the Panchaetothripini, but weak support for the tribe Tryphactothripini. No clear sister-group relationship could be identified for the New World genus Heliothrips, although it grouped with three old world genera Australothrips, Retithrips and Rhipiphorothrips. It is concluded that a morphological data set is not capable of producing a robust phylogeny of the Panchaetothripinae, and that the subject requires re-examination using molecular data.

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