scholarly journals Remarkable teleostean fishes from the Late Jurassic of southern Germany and their phylogenetic relationships

Fossil Record ◽  
2000 ◽  
Vol 3 (1) ◽  
pp. 137-179 ◽  
Author(s):  
G. Arratia
Keyword(s):  
New Taxa ◽  
Phylogenetic Relationships ◽  
Late Jurassic ◽  
Sister Group ◽  
Morphological Characters ◽  
Phylogenetic Position ◽  
New Genera ◽  
Phylogenetic Hypothesis ◽  
The Past ◽  
New Information

Complete descriptions, as preservation permits, are provided for new Late Jurassic taxa (e.g., †<i>Ascalabothrissops voelkli</i> n. gen. and n. sp., †<i>Anaethalion zapporum</i> n. sp., and †<i>Elopsomolos frickhingeri</i> n. gen. and n. sp.); the phylogenetic positions of these taxa are given, as well as an evaluation of the European teleosts during the Late Jurassic. <br><br> The relationships among certain fossil and extant teleosts are evaluated based on 191 unweighted morphological characters by using cladistic principles. The results suggest that †<i>Ascalabothrissops</i> n. gen. from the Kimmeridgian of Schamhaupten is the sister-taxon of †<i>Pachythrissops</i> from the Tithonian of Bavaria, and consequently is an ichthyodectiform. †<i>Anaethalion zapporum</i> n. sp., an elopiform, stands in an unresolved polytomy with †<i>A. angustus, †A. knorri</i>, and a clade formed by †<i>A. angustissimus</i> and more advanced elopiforms. The new results confirm Arratia (1997) that †<i>Anaethalion</i>, as presently understood, is a paraphyletic taxon. †<i>Elopsomolos frickhingeri</i> n. gen. and n. sp. forms a polytomy with †<i>Elopsomolos</i> sp. 1 and 3, and [<i>Elops + Megalops</i>]. Monophyly of the Kimmeridgian and Tithonian genus †<i>Elopsomolos</i> is not certain. <br><br> Following the new phylogenetic hypothesis, that includes new taxa and new characters, the elopomorphs stand as the primitive sister-group of osteoglossomorphs and more advanced teleosts. The new information does not affect the phylogenetic position of the main extant teleostean clades and confirms previous results by Arratia (1991, 1996, 1997, 1999). <br><br> The analysis of the elopiforms through time shows that the group had an important radiation during the Late Jurassic, to be replaced by new genera and species during the Cretaceous, and again during the Cenozoic. From numerous genera living in the past, elopiforms are represented now by two genera, <i>Elops</i> and <i>Megalops</i>. <br><br> Soweit es die Erhaltung zulässt, werden vollständige Beschreibungen der drei neuen spätjurassischen Taxa †<i>Ascalabothrissops voelkli</i> n. gen. et n. sp., †<i>Anaethalion zapporum</i> n. sp., und †<i>Elopsomolos frickhingeri</i> n. gen. et n. sp. gegeben. Die phylogenetische Stellung dieser Taxa als auch anderer spätjurassischer europäischer Teleosteer ist analysiert. <br><br> Die Verwandtschaftsbeziehungen innerhalb einiger fossiler und rezenter Teleosteer wurden auf der Basis von 191 nicht gewichteten morphologischen Merkmalen mit Hilfe der kladistischen Methode evaluiert. Als Ergebnis zeigt sich, dass †<i>Ascalabothrissops</i> n. gen. aus dem Kimmeridgium von Schamhaupten das Schwestertaxon von †<i>Pachythrissops</i> und damit ein Ichthyodectiformer ist. †<i>Anaethalion zapporum</i> n. sp., ein Elopiformer, steht in einer nicht auflösbaren Polytomie mit †<i>A. angustus, †A, knorri</i>, und einer Gruppe gebildet aus †<i>A. angustissimus</i> und weiter fortgeschrittenen Elopiformen. Die neuen Ergebnisse bestätigen Arratia (1997), dass †<i>Anaethalion</i>, wie zur Zeit umgrenzt, ein paraphylethisches Taxon darstellt. †<i>Elopsomolos frickhingeri</i> n. gen. et n. sp. bildet eine Polytomie mit †<i>Elopsomolos</i> sp. 1 und 3, und [<i>Elops + Megalops</i>]. Die Monophylie der Gattung †<i>Elopsomolos</i> aus dem Kimmeridgium und Tithonium ist nicht gesichert. <br><br> Nach der neuen phylogenetischen Hypothese, die neue Taxa und neue Merkmale einbezieht, sind die Elopomorphen die primitive Schwestergruppe der Osteoglossomorphen und weiter fortgeschrittener Teleosteer. Die neuen Ergebnisse beeinflussen die phylogenetische Stellung der rezenten Hauptgruppen der Teleosteer nicht und bestätigen frühere Ergebnisse von Arratia (1991, 1996, 1997, 1999). <br><br> Die Analyse der Elopiformen zeigt, dass die Gruppe eine bedeutende Radiation im Spätjura erlebte; neue Gattungen und Arten traten in der Kreide auf und dann wieder im Känozoikum. Im Gegensatz zu den zahlreichen fossilen Gattungen sind die Elopiformen heute nur durch zwei Gattungen vertreten, <i>Elops</i> und <i>Megalops</i>. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20000030108" target="_blank">10.1002/mmng.20000030108</a>

scholarly journals Restructuring the Ancorabolidae Sars (Copepoda, Harpacticoida) and Cletodidae T. Scott, with a new phylogenetic hypothesis regarding the relationships of the Laophontoidea T. Scott, Ancorabolidae and Cletodidae

2020 ◽  
Vol 96 (2) ◽  
pp. 455-498
Author(s):  
Kai Horst George
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Morphological Characteristics ◽  
Sister Group ◽  
Morphological Characters ◽  
Sister Group Relationship ◽  
Phylogenetic Hypothesis ◽  
The Family ◽  
Swimming Leg

Uncovering the systematics of CopepodaHarpacticoida, the second-most abundant component of the meiobenthos after Nematoda, is of major importance for any further research dedicated especially to ecological and biogeographical approaches. Based on the evolution of the podogennontan first swimming leg, a new phylogenetic concept of the Ancorabolidae Sars and Cletodidae T. Scott sensu Por (Copepoda, Harpacticoida) is presented, using morphological characteristics. It confirms the polyphyletic status of the Ancorabolidae and its subfamily Ancorabolinae Sars and the paraphyletic status of the subfamily Laophontodinae Lang. Moreover, it clarifies the phylogenetic relationships of the so far assigned members of the family. An exhaustive phylogenetic analysis was undertaken using 150 morphological characters, resulting in the establishment of a now well-justified monophylum Ancorabolidae. In that context, the Ancorabolus-lineage sensu Conroy-Dalton and Huys is elevated to sub-family rank. Furthermore, the membership of Ancorabolina George in a rearranged monophylum Laophontodinae is confirmed. Conversely, the Ceratonotus-group sensu Conroy-Dalton is transferred from the hitherto Ancorabolinae to the Cletodidae. Within these, the Ceratonotus-group and its hypothesised sister-group Cletodes Brady are combined to form a monophyletic subfamily Cletodinae T. Scott, subfam. nov. Consequently, it was necessary to restructure the Ancorabolidae, Ancorabolinae and Laophontodinae and extend the Cletodidae to include the displacement and exclusion of certain taxa. Moreover, comparison of the Ancorabolidae, Cletodidae, Laophontoidea and other Podogennonta shows that the Ancorabolidae and Cletodidae form sister-groups in a monophylum Cletodoidea Bowman and Abele, which similarly has a sister-group-relationship with the Laophontoidea T. Scott. According to the present study, both taxa constitute a derived monophylum within the Podogennonta Lang.

scholarly journals An appraisal of the phylogenetic relationships of Hypoptopomatini cascudinhos with description of two new genera and three new species (Siluriformes: Loricariidae)

2017 ◽  
Vol 15 (4) ◽  
Author(s):  
Maria Laura S. Delapieve ◽  
Pablo Lehmann A ◽  
Roberto E. Reis
Keyword(s):  
New Species ◽  
New Taxa ◽  
Retention Index ◽  
Phylogenetic Relationships ◽  
Morphological Characters ◽  
Data Matrix ◽  
New Genera ◽  
Consensus Tree ◽  
Strict Consensus Tree ◽  
Three New Species

ABSTRACT The discovery of three new taxa of Hypoptotopomatini with ambiguous generic assignment prompted a reanalysis of the phylogenetic relationships of the tribe. The analysis focused on a data matrix of 56 terminals and 107 morphological characters comprising the three new taxa, most species of Hypoptopoma and Otocinclus, and all other species of the tribe. The 162 maximally parsimonious trees of 382 steps, consistency index of 0.41, and retention index of 0.83 were then summarized in a strict consensus tree. The results confirm the monophyly of the Hypoptopomatini, recover four genera as monophyletic (Acestridium, Hypoptopoma, Niobichthys, and Otocinclus), revealed Hypoptopoma and Oxyropsis to be non-monophyletic; and revealed two new genera within Hypoptopomatini. Additionally, Otocinclus was found to be sister to a group with all remaining genera of the tribe; Acestridium and Niobichthys were found to be sister to each other and that clade sister to a group formed by ((Leptotocinclus + Hypoptopoma [part]) + (Nannoxyropsis (Oxyropsis + Hypoptopoma [part]))). Based on this framework, changes to the classification and the taxonomy of the Hypoptopomatini are suggested and the new taxa are described.

scholarly journals New Cretaceous antlion-like lacewings promote a phylogenetic reappraisal of the extinct myrmeleontoid family Babinskaiidae

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiumei Lu ◽  
Bo Wang ◽  
Xingyue Liu
Keyword(s):  
Phylogenetic Inference ◽  
Sister Group ◽  
Morphological Characters ◽  
Phylogenetic Position ◽  
New Genera ◽  
Monophyletic Clade ◽  
Morphological Diversification ◽  
Phylogenetic Placement ◽  
The Rich ◽  
Family Based

AbstractBabinskaiidae is an extinct family of the lacewing superfamily Myrmeleontoidea, currently only recorded from the Cretaceous. The phylogenetic position of this family is elusive, with inconsistent inferences in previous studies. Here we report on three new genera and species of Babinskaiidae from the mid-Cretaceous Kachin amber of Myanmar, namely Calobabinskaia xiai gen. et sp. nov., Stenobabinskaia punctata gen. et sp. nov., and Xiaobabinskaia lepidotricha gen. et sp. nov. These new babinskaiids are featured by having specialized characters, such as the rich number of presectoral crossveins and the presence of scaly setae on forewing costal vein, which have not yet been found in this family. The exquisite preservation of the Kachin amber babinskaiids facilitate a reappraisal of the phylogenetic placement of this family based on adult morphological characters. Our result from the phylogenetic inference combining the data from fossil and extant myrmeleontoids recovered a monophyletic clade composed of Babinskaiidae and another extinct family Cratosmylidae, and further assigned this clade to be sister group to a clade including Nemopteridae, Palaeoleontidae, and Myrmeleontidae. Babinskaiidae appears to be a transitional lineage between Nymphidae and advanced myrmeleontoids, with ancient morphological diversification.

scholarly journals Revision of Undorosaurus, a mysterious Late Jurassic ichthyosaur of the Boreal Realm

2019 ◽  
Author(s):  
Nikolay Zverkov
Keyword(s):  
New Taxa ◽  
Type Species ◽  
Late Jurassic ◽  
Sister Group ◽  
Phylogenetic Position ◽  
Posterior Edge ◽  
Diagnostic Features ◽  
Type Series ◽  
Phylogenetic Hypotheses ◽  
Boreal Realm

Recent study of ophthalmosaurid ichthyosaurs has brought us a number of new taxa, however, the validity of several ophthalmosaurid taxa from the Volgian (Tithonian) of European Russia still remains unclear, complicating the comparisons and in some cases affecting taxonomic decisions of new contributions. A revision of the type series of all three species of Undorosaurus, erected by Efimov in 1999, reveals the potential validity of two of them. This contradicts previous research, which concluded that only the type species, U. gorodischensis, is valid. Furthermore, examination of the holotype of Cryopterygius kristiansenae from the coeval strata of Svalbard show that it is synonymous with Undorosaurus gorodischensis sharing all diagnostic features of the species, especially those related to forelimb morphology: humerus with extensive anteroposteriorly elongate proximal end, poorly pronounced trochanter dorsalis and reduced deltopectoral crest; and ulna proximodistally elongate and not involved in perichondral ossification on its whole posterior edge. This supports the idea of intensive exchange of ichthyosaurs between the Middle Russian Sea and other Boreal seas in the Late Jurassic. In order to resolve the phylogenetic position of Undorosaurus within Ophthalmosauridae as well as relations of other ophthalmosaurids, a new dataset including 33 taxa and 106 characters, 23 of which are new, was compiled. The results of this analysis challenge all previous phylogenetic hypotheses for Ophthalmosauridae in a number of aspects including Undorosaurus spp. recovered deeply nested within Platypterygiinae as a sister group to derived platypterygiines.

Corrigendum to: Cladistic analysis and revision of Piestus Gravenhorst with remarks on related genera (Coleoptera : Staphylinidae : Piestinae)

2013 ◽  
Vol 27 (1) ◽  
pp. 129
Author(s):  
Edilson Caron ◽  
Cibele S. Ribeiro-Costa ◽  
Alfred F. Newton
Keyword(s):  
Cladistic Analysis ◽  
Taxonomic Revision ◽  
Sister Group ◽  
Morphological Characters ◽  
Valid Species ◽  
Phylogenetic Position ◽  
Neotropical Forests ◽  
Rove Beetles ◽  
New Synonyms ◽  
Branch Support

Rove beetles of the genus Piestus Gravenhorst, 1806 are commonly captured under the bark of or inside decaying logs from Neotropical forests. Piestus belongs to the subfamily Piestinae, historically an ill-defined dumping-ground for Staphylinidae defined by plesiomorphic characters, but which has gradually been restricted in concept and currently includes only six additional extant genera worldwide. Piestinae in this restricted sense has been considered a probably monophyletic subfamily, but its status and phylogenetic position, as a possible sister-group of Osoriinae within the recently proposed Oxyteline group of staphylinid subfamilies, are uncertain and need confirmation. The main aim of the present study was to provide a morphological cladistic analysis and complete taxonomic revision of Piestus, which, as the type and most speciose genus of Piestinae, is critical for future phylogenetic studies involving the subfamily. In our study, the monophyly of Piestus is established and phylogenetic relationships among its species are proposed based on 70 adult morphological characters. Piestus is supported by 11 synapomorphies and high branch support. All species of Piestus are revised and the genus is redefined. The genus contains 43 species, including 13 species described here for the first time. The previously proposed subgenera Antropiestus Bernhauer, 1917, Eccoptopiestus Scheerpeltz, 1952, Elytropiestus Scheerpeltz, 1952, Lissopiestus Scheerpeltz, 1952, Piestus s. str., Trachypiestus Scheerpeltz, 1952 and Zirophorus Dalman, 1821 have not been confirmed, as they were found to be poly- or paraphyletic, or are here removed from Piestus, and therefore subgenera are not used. The main taxonomic changes are as follows. Lissopiestus, syn. nov. is proposed as new synonym of Eleusis Laporte, 1835 and its species, E. interrupta (Erichson, 1840), comb. rest., is transferred again to that genus. Antropiestus, syn. nov. and Eccoptopiestus, syn. nov. are proposed as new synonyms of Hypotelus Erichson, 1839 and their species, H. laevis (Solsky, 1872), comb. nov. and H. andinus (Bernhauer, 1917), comb. nov., are transferred to Hypotelus. Fourteen new synonymies are proposed (valid species listed first): P. lacordairei Laporte, 1835 = Z. furcatus Sharp, 1887, syn. nov.; P. capricornis Laporte, 1835 = P. frontalis Sharp, 1876, syn. nov.; P. pennicornis Fauvel, 1864 = P. plagiatus Fauvel, 1864, syn. nov.; P. rectus Sharp, 1876, syn. nov.; P. pygialis Fauvel, 1902, syn. nov.; P. surinamensis Bernhauer, 1928, syn. nov.; P. minutus Erichson, 1840 = P. nigrator Fauvel, 1902, syn. nov.; P. sulcatus Gravenhorst, 1806 = P. sanctaecatharinae Bernhauer, 1906, syn. nov.; P. condei Wendeler, 1955, syn. nov.; P. gounellei Fauvel, 1902 = P. wasmanni Fauvel, 1902, syn. nov.; P. mexicanus Laporte, 1835 = P. alternans Sharp, 1887, syn. nov.; P. aper Sharp, 1876 = P. schadei Scheerpeltz, 1952, syn. nov.; P. angularis Fauvel, 1864 = P. crassicornis Sharp, 1887, syn. nov.; H. andinus (Bernhauer, 1917) = P. strigipennis Bernhauer, 1921, syn. nov. One species is revalidated: P. fronticornis (Dalman, 1821), stat. rev., and one synonym is restored: P. penicillatus (Dalman, 1821) = P. erythropus Erichson, 1840, syn. rest. Neotypes are designated for P. lacordairei Laporte, 1835 and Oxytelus bicornis Olivier, 1811, and lectotypes are designated for P. puncticollis Fauvel, 1902, P. capricornis variety muticus Fauvel, 1902, P. zischkai Scheerpeltz, 1951, P. pennicornis Fauvel, 1864, P. plagiatus Fauvel, 1864, P. pygmaeus Laporte, 1835, P. niger Fauvel 1864, P. minutus Erichson, 1840, P. nigratror Fauvel, 1902, P. sulcatus Gravenhorst, 1806, P. sanctaecatharinae Bernhauer, 1906, P. sulcipennis Scheerpeltz, 1952, P. aper Sharp, 1876, P. schadei Scheerpeltz, 1952 and P. andinus Bernhauer, 1917.

scholarly journals On a remarkable new species of <i>Tharsis</i>, a Late Jurassic teleostean fish from southern Germany: its morphology and phylogenetic relationships

Fossil Record ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 1-23 ◽  
Author(s):  
Gloria Arratia ◽  
Hans-Peter Schultze ◽  
Helmut Tischlinger
Keyword(s):  
New Species ◽  
Late Jurassic ◽  
Strong Support ◽  
Sister Group ◽  
Common Species ◽  
Upper Jurassic ◽  
Morphological Characters ◽  
Morphological Description ◽  
Sister Group Relationship ◽  
Southern Germany

Abstract. A complete morphological description, as preservation permits, is provided for a new Late Jurassic fish species (Tharsis elleri) together with a revision and comparison of some morphological features of Tharsis dubius, one of the most common species from the Solnhofen limestone, southern Germany. An emended diagnosis of the genus Tharsis – now including two species – is presented. The new species is characterized by a combination of morphological characters, such as the presence of a complete sclerotic ring formed by two bones placed anterior and posterior to the eye, a moderately short lower jaw with quadrate-mandibular articulation below the anterior half of the orbit, caudal vertebrae with neural and haemal arches fused to their respective vertebral centrum, and parapophyses fused to their respective centrum. A phylogenetic analysis based on 198 characters and 43 taxa is performed. Following the phylogenetic hypothesis, the sister-group relationship Ascalaboidae plus more advanced teleosts stands above the node of Leptolepis coryphaenoides. Both nodes have strong support among teleosts. The results confirm the inclusion of Ascalabos, Ebertichthys and Tharsis as members of this extinct family. Tharsis elleri n. sp. (LSID urn:lsid:zoobank.org:act:6434E6F5-2DDD-48CF-A2B1-827495FE46E6, date: 13 December 2018) is so far restricted to one Upper Jurassic German locality – Wegscheid Quarry near Schernfeld, Eichstätt – whereas Tharsis dubius is known not only from Wegscheid Quarry, but also from different localities in the Upper Jurassic of Bavaria, Germany, and Cerin in France.

Fourth addendum to the synoptic review of red algal genera

2019 ◽  
Vol 62 (4) ◽  
pp. 355-367 ◽  
Author(s):  
Craig W. Schneider ◽  
Michael J. Wynne
Keyword(s):  
New Taxa ◽  
Red Algae ◽  
New Genera ◽  
Half Century ◽  
Hierarchical Framework ◽  
The Third ◽  
The Past ◽  
Red Algal ◽  
Molecular Sequencing

Abstract The fourth addendum to Schneider and Wynne’s 2007 “A synoptic review of the classification of red algal genera a half century after Kylin’s 1956 ‘Die Gattungen der Rhodophyceen’” is presented, covering the names of genus- and higher-level taxa added or modified since our third addendum (Bot. Mar. 59: 397–404). Since that synopsis, we added 21 new genera in a first addendum, 27 in the second, and 40 in the third, demonstrating the increasing amount of genetic work over more than a decade. In this fourth addendum, we add 58 new genera to the list of red algae as well as many new taxa in the hierarchical framework over the past 3 years. Based upon molecular sequencing, other genera reinstated from synonymy studies are included.

The phylogenetic relationships of the two-winged South American Leptophlebiidae genera revisited with first description of the male imago of Bessierus Thomas & Orth (Insecta: Ephemeroptera)

Zootaxa ◽  
2019 ◽  
Vol 4674 (3) ◽  
pp. 375-385
Author(s):  
EDUARDO DOMÍNGUEZ ◽  
MARÍA GABRIELA CUEZZO ◽  
SIMÓN CLAVIER
Keyword(s):  
Sister Group ◽  
Sister Group Relationship ◽  
South American ◽  
Phylogenetic Hypothesis ◽  
New Information ◽  
Statistical Support ◽  
The Stability ◽  
New Diagnosis ◽  
Relationship Of ◽  
First Time

Four of the 43 genera of South American Leptophlebiidae are dipterous. A previous phylogenetic hypothesis supported that clade Askola+Hagenulopsis, and that Bessierus+Perissophlebiodes, are sister groups of the Farrodes complex. Adults of Bessierus and Perissophlebiodes were not known but posteriorly Perissophlebiodes male imago was described. Here, we describe the male imago of Bessierus for the first time. Both genera share, besides the absence of the hind wings, the asymmetrical fork of MA, symmetrical fork of MP, dissimilar tarsal claws, and forceps sockets fused. Along with the description of the imago, a new diagnosis for the genus Bessierus is presented, also updating the identification key with this new information. A new cladistics analysis is performed to test the stability of the proposed relationships of these four genera within Leptophlebiidae. We obtained a single cladistic hypothesis where the addition of Bessierus adult characters resulted in new synapomorphies for the (Bessierus, Perissophlebiodes) clade, and improved its clade statistical support. The fused forceps sockets resulted in a synapomorphy uniting Bessierus, Perissophlebiodes and Simothraulopsis. As a result of this new analysis, the hypothesis of independent losses of the hind wings in the two dipterous groups studied is supported. The Farrodes lineage is not supported as proposed in previous studies, being restricted only to (Farrodes (Simothraulopsis, Homothraulus)) while the identity of “Perissophlebiodes lineage” is supported. The sister group relationship of Rondophlebia is not clearly defined. 

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.

scholarly journals Northern Apennines as centre of speciation: a new Verdanus species group (Hemiptera, Cicadomorpha, Cicadellidae) from Italy and its phylogenetic relationships with V. bensoni and the V. limbatellus group

Zootaxa ◽  
2009 ◽  
Vol 2264 (1) ◽  
pp. 1-22 ◽  
Author(s):  
ADALGISA GUGLIELMINO ◽  
CHRISTOPH BÜCKLE
Keyword(s):  
New Taxa ◽  
Phylogenetic Relationships ◽  
Cladistic Analysis ◽  
Morphological Characters ◽  
Species Group ◽  
Northern Apennines ◽  
Dispersal Ability ◽  
Group V ◽  
Central Eurasia ◽  
Limited Dispersal

A small sector of Northern Apennines the Tuscan-Emilian Apennines constitutes an interesting diversity centre of a new Verdanus species group closely related to V. bensoni and the V. limbatellus group. It consists of three species: V. tyrannus sp. nov., V. saurosus sp. nov. and V. rosaurus sp. nov., the latter with two subspecies, V. rosaurus rosaurus ssp. nov. and V. rosaurus rex ssp. nov., which doubtless form a monophyletic group (V. rosaurus group). Data on their distribution, ecology and life cycle are added to their original descriptions. The new taxa live allopatrically in a very restricted area and thus occupy a distribution gap of another species group of Verdanus, the V. abdominalis group, present in Italy in the mountain regions of the Alps and Central and Southern Apennines. A hypothesis of the origin of the new taxa is presented based on the ecological conditions in the Tuscan-Emilian Apennines during the last Postglacial period and on the limited dispersal ability of these normally brachypterous insects. Possible synapomorphic characters and phylogenetic relationships of the new taxa with each other and with V. bensoni (China) and the V. limbatellus group (V. limbatellus (Zetterstedt), V. kyrilli (Emeljanov), V. sichotanus (Anufriev), V. kaszabi (Dlabola)) are discussed and a cladistic analysis is conducted. Comparing V. bensoni and the V. limbatellus group on the one hand and the V. rosaurus group on the other, some morphological characters appear to change often in parallel on the same paths, independently from the phylogenetic hypothesis. Remarkably, within the same morphological characters the range of variation among species inhabiting the comparatively minute area of the Tuscan-Emilian Apennines is similar to that found among other taxa distributed across vast areas of northern and central Eurasia.

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