scholarly journals Molecular systematics of western North American cyprinids (Cypriniformes: Cyprinidae)

Zootaxa ◽  
2012 ◽  
Vol 3586 (1) ◽  
pp. 281 ◽  
Author(s):  
SUSANA SCHÖNHUTH ◽  
DENNIS K. SHIOZAWA ◽  
THOMAS E. DOWLING ◽  
RICHARD L. MAYDEN

The phylogenetic or evolutionary relationships of species of Cypriniformes, as well as their classification, is in a era offlux. For the first time ever, the Order, and constituent Families are being examined for relationships within aphylogenetic context. Relevant findings as to sister-group relationships are largely being inferred from analyses of bothmitochondrial and nuclear DNA sequences. Like the vast majority of Cypriniformes, due to an overall lack of anyphylogenetic investigation of these fishes since Hennig’s transformation of the discipline, changes in hypotheses ofrelationships and a natural classification of the species should not be of surprise to anyone. Basically, for most taxa noproperly supported phylogenetic hypothesis has ever been done; and this includes relationships with reasonable taxonand character sampling of even families and subfamilies. As such, like others, many western North American cyprinidgenera have had a controversial taxonomic and systematic history.Our effort to better understand the evolutionary history of this artificial geographic grouping of species (Western)surveyed taxa and characters broadly. We analyzed 127 taxa (71 species) from 36 genera, including representative taxafrom all 22 western genera hypothesized to form the Western Clade sensu Coburn and Cavender (1992). Our evaluationalso included additional sampling from a heterogeneous array of species from the western genera Algansea, Gila,Lepidomeda, Ptychocheilus and Siphateles. Resulting phylogenetic inferences, based on one mitochondrial and threenuclear genes (mtDNA: cytb; nDNA: Rag1, Rhod, S7), consistently resolved a well-supported Western Clade, but oneinclusive of Chrosomus erythrogaster. This taxon, always formed the sister group to the extant species of Gila plus 10other western genera. Our Western Clade is qualitatively different from that of prior studies and does not include thegenera Agosia, Algansea, Iotichthys, Lepidomeda, Meda, Mylocheilus, Plagopterus, Pogonichthys, Rhinichthys, Tiarogaor Yuriria. All of these taxa were, however, included in Coburn and Cavender´s (1992) Western Clade. Our broader-scalesurvey and increased character sampling were always resolved these latter taxa within one of two different major clades:the OPM Clade (sensu Mayden 1989) and the Creek Chub—Plagopterin Clade (sensu Simons et al. 2003). Ourhypothesized Western Clade places Orthodon sister to a Western Chub-Pikeminnow Clade also inclusive of Acrocheilus,Eremichthys, Gila, Hesperoleucus, Lavinia, Moapa, Mylopharodon, Ptychocheilus, Relictus and Siphateles. The lattertaxa have traditionally been recognized at the generic level, simply on the basis of their morphological distinctivenessand not on the basis of a phylogenetic evaluation of relationships. Composition of our Western Chub-Pikeminnow Cladealso reveals genetic divergences between species of some genera (Gila, Ptychocheilus, Siphateles) comparable to geneticdivergences documented between genera within the Western Clade. Relationships for these 10 genera also highlighttaxonomic inconsistencies relative to recent phylogenetic analysis and, in some cases, are in need of focused attentionusing morphology or additional molecular data to test relationships that will eventually establish a stable classification.Some of these genera are clearly unnatural relative to other genera and their classification or ranking is an obligatory change in modern science of phylogenetics.

Botany ◽  
2008 ◽  
Vol 86 (9) ◽  
pp. 1039-1064 ◽  
Author(s):  
Stephen R. Downie ◽  
Deborah S. Katz-Downie ◽  
Feng-Jie Sun ◽  
Chang-Shook Lee

Intergeneric phylogenetic relationships within Apiaceae tribe Oenantheae were investigated using sequence data from the chloroplast DNA psbI–5′trnK(UUU) and nuclear ribosomal DNA internal transcribed spacer regions. One hundred and thirty-one accessions were examined, representing all 17 genera of the tribe and approximately one-half of its species. The cpDNA region includes four intergenic spacers and the rps16 intron and these noncoding loci were analyzed separately to assess their relative utility for resolving relationships. Separate maximum parsimony analyses of the entire psbI–5′trnK(UUU) and ITS regions, each with and without scored indels, yielded concordant trees. Phylogenies derived from maximum parsimony, Bayesian, or maximum likelihood analyses of combined chloroplast and nuclear DNA sequences for 82 accessions were highly resolved, well supported, and consistent. Among the five noncoding loci examined, the trnQ(UUG)–5′rps16 and 3′rps16–5′trnK(UUU) intergenic spacers are the most variable, with the latter contributing the greatest total number of parsimony informative characters relative to its size. The North American genera Atrema , Cynosciadium , Daucosma , Limnosciadium , Neogoezia , Oxypolis , Ptilimnium , and Trepocarpus ally with the western hemispheric and Australasian genus Lilaeopsis in a strongly supported North American Endemics clade that is a sister group to a clade composed primarily of Old World taxa ( Berula sensu lato, Cryptotaenia , Helosciadium , and Sium ). Oxypolis and Ptilimnium are not monophyletic, with the rachis-leaved members of each comprising a clade separate from their compound-leaved congeners. Dispersal-vicariance analysis suggests that the ancestors of the North American Endemics clade probably originated in Canada and the USA or in a broader ancestral area including Mexico and South America.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11502
Author(s):  
W. Bryan Jennings

Here, I review phylogenetic studies of the lizard family Pygopodidae, a group of 47 extant species that diversified in Australia and New Guinea. The goal of this study was to examine published phylogenetic and phylogenomic hypotheses on pygopodids to identify the strengths and weaknesses in our understanding of their phylogeny. Many parts of the pygopodid family tree are well established by multiple independent tree inferences including: (1) all multispecies genera (i.e., Aprasia, Delma, Lialis, Pletholax, and Pygopus) are monophyletic groups; (2) the root of the pygopodid tree is located along the branch leading to the Delma clade, thus showing that Delma is the sister group to all other pygopodid genera; (3) the Aprasia repens group, Delma tincta group, and several other groups of closely related species are demonstrated to be monophyletic entities; and (4) the monotypic Paradelma orientalis is the sister lineage to the Pygopus clade. Based on accumulated phylogenetic evidence, two taxonomic recommendations are given: Paradelma merits generic status rather than being subsumed into Pygopus as some earlier studies had suggested, and the monotypic Aclys concinna should be recognized as a member of Delma (following current practice) until future studies clarify its placement inside or outside the Delma clade. One chronic problem with phylogenetic studies of pygopodids, which has limited the explanatory power of many tree hypotheses, concerns the undersampling of known species. Although the continual addition of newly described species, especially over the past two decades, has been a major reason for these taxon sampling gaps, deficits in species sampling for ingroups and/or outgroups in several studies of pygopodid species complexes has confounded the testing of some ingroup monophyly hypotheses. Ancient hybridization between non-sister lineages may also be confounding attempts to recover the relationships among pygopodids using molecular data. Indeed, such a phenomenon can explain at least five cases of mito-nuclear discordance and conflicts among trees based on nuclear DNA datasets. Another problem has been the lack of consensus on the relationships among most pygopodid genera, an issue that may stem from rapid diversification of these lineages early in the group’s history. Despite current weaknesses in our understanding of pygopodid phylogeny, enough evidence exists to clarify many major and minor structural parts of their family tree. Accordingly, a composite tree for the Pygopodidae was able to be synthesized. This novel tree hypothesis contains all recognized pygopodid species and reveals that about half of the clades are corroborated by multiple independent tree hypotheses, while the remaining clades have less empirical support.


2012 ◽  
Vol 279 (1737) ◽  
pp. 2396-2401 ◽  
Author(s):  
Rachunliu G. Kamei ◽  
Diego San Mauro ◽  
David J. Gower ◽  
Ines Van Bocxlaer ◽  
Emma Sherratt ◽  
...  

The limbless, primarily soil-dwelling and tropical caecilian amphibians (Gymnophiona) comprise the least known order of tetrapods. On the basis of unprecedented extensive fieldwork, we report the discovery of a previously overlooked, ancient lineage and radiation of caecilians from threatened habitats in the underexplored states of northeast India. Molecular phylogenetic analyses of mitogenomic and nuclear DNA sequences, and comparative cranial anatomy indicate an unexpected sister-group relationship with the exclusively African family Herpelidae. Relaxed molecular clock analyses indicate that these lineages diverged in the Early Cretaceous, about 140 Ma. The discovery adds a major branch to the amphibian tree of life and sheds light on both the evolution and biogeography of caecilians and the biotic history of northeast India—an area generally interpreted as a gateway between biodiversity hotspots rather than a distinct biogeographic unit with its own ancient endemics. Because of its distinctive morphology, inferred age and phylogenetic relationships, we recognize the newly discovered caecilian radiation as a new family of modern amphibians.


2012 ◽  
Vol 62 (1) ◽  
pp. 427-446 ◽  
Author(s):  
Susana Schönhuth ◽  
David M. Hillis ◽  
David A. Neely ◽  
Lourdes Lozano-Vilano ◽  
Anabel Perdices ◽  
...  

Zootaxa ◽  
2007 ◽  
Vol 1668 (1) ◽  
pp. 413-425 ◽  
Author(s):  
P. J. GULLAN ◽  
L. G. COOK

The superfamily Coccoidea contains nearly 8000 species of plant-feeding hemipterans comprising up to 32 families divided traditionally into two informal groups, the archaeococcoids and the neococcoids. The neococcoids form a monophyletic group supported by both morphological and genetic data. In contrast, the monophyly of the archaeococcoids is uncertain and the higher level ranks within it have been controversial, particularly since the late Professor Jan Koteja introduced his multi-family classification for scale insects in 1974. Recent phylogenetic studies using molecular and morphological data support the recognition of up to 15 extant families of archaeococcoids, including 11 families for the former Margarodidae sensu lato, vindicating Koteja’s views. Archaeococcoids are represented better in the fossil record than neococcoids, and have an adequate record through the Tertiary and Cretaceous but almost no putative coccoid fossils are known from earlier. In contrast, the sister group of the scale insects (Aphidoidea) has a more informative Jurassic and Triassic record. Relationships among most scale insect families are unresolved in phylogenetic trees based on nuclear DNA sequences, and most nodes in trees based on morphological data, including those from adult males, are poorly supported. Within the neococcoids, the Eriococcidae is not monophyletic and the monophyly of the Coccidae and Diaspididae may be compromised by the current family-level recognition of a few species-poor autapomorphic groups.


2015 ◽  
Author(s):  
Natália Rizzo Friol ◽  
Flávio de Barros Molina ◽  
Hussam El Dine Zaher

Background. Phrynops present four valid species, including P. geoffroanus that might represents a complex of cryptic species. Here, we provide a preliminary analysis of the taxonomy and phylogenetic affinities within Phrynops, with special reference to the taxonomic status of populations of P. geoffroanus and P. tuberosus, and the recognition of a new species from Southern Brazil. Methods. We studied populations from ten Brazilian river basins. A linear morphometric analysis was performed in order to define taxonomically distinct populations. Also, a phylogenetic analysis using morphology and molecular data (sequenced for the genes R35, RAG2, c-mos, cytb, ND4, and 12S) were carried out. Three distinct sets of phylogenetic analyses were performed: parsimony to morphological and combined data, and maximum likelihood to molecular data. Results. The combined analysis shows that Phrynops represents a well supported clade. The set of skeletal data supports Mesoclemmys as the sister group of Phrynops, whereas the molecular and combined data sets show Phrynops as the sister group of a clade composed by all the remaining genera of Chelidae, except Hydromedusa. Our morphological analyses suggest that P. hilarii is the sister group of P. geoffroanus, but in both molecular and combined analyses, P. hilarii appears nested within the clade formed by the populations of P. geoffroanus. Futhermore, P. tuberosus and P. geoffroanus are not distinguishable by the set of osteological and morphometric data. On the other hand, both morphometric and osteological data show that the population of P. geoffroanus from the Paraná river basin is a distinct species. Discussion. The sister group relationships of Phrynops could not be clearly defined due to the different topologies achieved. Phrynops hilarii is included within of P. geoffroanus in both molecular and combined data, but this position has little statistical support and therefore does not express a clear position of P. hilarii within the genus Phrynops. Besides, we were not able to distinguish P. geoffroanus and P. tuberosus. However, a sampling of specific locations are still needed to objectively define the taxonomic status of P. tuberosus. Finally, the population of P. geoffroanus from the Paraná basin is clearly distinct from the remaining populations of this species. Qualitative osteological characters and morphometric results seem to demonstrate that this population is a new species of Phrynops.


PhytoKeys ◽  
2019 ◽  
Vol 134 ◽  
pp. 83-96
Author(s):  
Taner Özcan

Nepeta viscida and N. nuda subsp. nuda and N. × tmolea were examined in this study. Mainly fresh leaf pieces, dried with silica grains, were used for DNA extraction procedures via DNA isolation kits. Standard PCR techniques were executed using three different primer sets (one nuclear DNA region (nrITS) and two chloroplast DNA regions (rpl32-trnL and trnA(Leu)-trnA(Phe)-trnL-F). DNA sequences were analysed and evaluated using different molecular approaches and software. Consequently, the inconstant molecular structure and hybrid nature of N. × tmolea specimens were shown and interpreted in this study. According to our result, N. × tmolea have some intermediate characters compared to its parents. nrITS data give more information phylogenetically, and also the most polymorphic loci are seen in nrITS data. Morphological and molecular data contribute to define separation of N. × tmolea. Consequently, the inconstant molecular structure and hybrid nature of N. × tmolea specimens were shown and interpreted in this study.


2021 ◽  
Author(s):  
Anna A. Namyatova ◽  
Michael D. Schwartz ◽  
Gerasimos Cassis

The Lygus-complex is one of the most taxonomically challenging groups of Miridae (Heteroptera), and its Australian fauna is poorly studied. Here we examine the Australian taxa of the Lygus-complex using morphological and molecular methods. After a detailed morphological study of the material collected throughout Australia, Taylorilygus nebulosus is transferred to Diomocoris, with the genus recorded for the first time in this country. Taylorilygus apicalis, also widely distributed in Australia, is redescribed on the basis of Australian material. The genus Micromimetus is recorded for the first time in Australia, with M. celiae, sp. nov., M. hannahae, sp. nov., M. nikolai, sp. nov. and M. shofneri, sp. nov. described as new to science. Micromimetus pictipes is redescribed and its distributional range is increased. The monophyly of the Lygus-complex and relationships within this group were tested using cytochrome c oxidase subunit I (COI), 16S rRNA, 18S rRNA and 28S rRNA markers. The Lygus-complex has been found to be non-monophyletic. Phylogeny confirmed the monophyly of Micromimetus, and it has shown that Taylorilygus apicalis is closer to Micromimetus species than to Diomocoris nebulosus. This study is the initial step in understanding the Lygus-complex phylogeny; analyses with more taxa, more genes and morphology are needed to reveal the interrelationships within this group, and sister-group relationships of Australian taxa. http://zoobank.org/urn:lsid:zoobank.org:pub:7393D96B-2BBA-438D-A134-D372EFE7FB9E


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