scholarly journals The systematic position of the enigmatic thyreophoran dinosaurParanthodon africanus, and the use of basal exemplifiers in phylogenetic analysis

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4529 ◽  
Author(s):  
Thomas J. Raven ◽  
Susannah C.R. Maidment
Keyword(s):  
South Africa ◽  
Phylogenetic Analysis ◽  
Lower Cretaceous ◽  
Phylogenetic Analyses ◽  
Systematic Position ◽  
Type Material ◽  
Sister Taxon ◽  
Phylogenetic Position ◽  
Taxonomic Assignment

The first African dinosaur to be discovered,Paranthodon africanuswas found in 1845 in the Lower Cretaceous of South Africa. Taxonomically assigned to numerous groups since discovery, in 1981 it was described as a stegosaur, a group of armoured ornithischian dinosaurs characterised by bizarre plates and spines extending from the neck to the tail. This assignment has been subsequently accepted. The type material consists of a premaxilla, maxilla, a nasal, and a vertebra, and contains no synapomorphies of Stegosauria. Several features of the maxilla and dentition are reminiscent of Ankylosauria, the sister-taxon to Stegosauria, and the premaxilla appears superficially similar to that of some ornithopods. The vertebral material has never been described, and since the last description of the specimen, there have been numerous discoveries of thyreophoran material potentially pertinent to establishing the taxonomic assignment of the specimen. An investigation of the taxonomic and systematic position ofParanthodonis therefore warranted. This study provides a detailed re-description, including the first description of the vertebra. Numerous phylogenetic analyses demonstrate that the systematic position ofParanthodonis highly labile and subject to change depending on which exemplifier for the clade Stegosauria is used. The results indicate that the use of a basal exemplifier may not result in the correct phylogenetic position of a taxon being recovered if the taxon displays character states more derived than those of the basal exemplifier, and we recommend the use, minimally, of one basal and one derived exemplifier per clade.Paranthodonis most robustly recovered as a stegosaur in our analyses, meaning it is one of the youngest and southernmost stegosaurs.

scholarly journals The systematic position of the enigmatic thyreophoran dinosaur Paranthodon africanus, and the use of basal exemplifiers in phylogenetic analysis

2018 ◽  
Author(s):  
Tom Raven ◽  
Susannah C. R. Maidment
Keyword(s):  
South Africa ◽  
Phylogenetic Analysis ◽  
Lower Cretaceous ◽  
Phylogenetic Analyses ◽  
Systematic Position ◽  
Type Material ◽  
Sister Taxon ◽  
Phylogenetic Position ◽  
Taxonomic Assignment

The first African dinosaur to be discovered, Paranthodon africanus was found in 1845 in the Lower Cretaceous of South Africa. Taxonomically assigned to numerous groups since discovery, in 1981 it was described as a stegosaur, a group of armoured ornithischian dinosaurs characterised by bizarre plates and spines extending from the neck to the tail. This assignment has been subsequently accepted. The type material consists of a premaxilla, maxilla, a nasal, and a vertebra, and contains no synapomorphies of Stegosauria. Several features of the maxilla and dentition are reminiscent of Ankylosauria, the sister-taxon to Stegosauria, and the premaxilla appears superficially similar to that of some ornithopods. The vertebral material has never been described, and since the last description of the specimen, there have been numerous discoveries of thyreophoran material potentially pertinent to establishing the taxonomic assignment of the specimen. An investigation of the taxonomic and systematic position of Paranthodon is therefore warranted. This study provides a detailed re-description, including the first description of the vertebra. Numerous phylogenetic analyses demonstrate that the systematic position of Paranthodon is highly labile and subject to change depending on which exemplifier for the clade Stegosauria is used. The results indicate that the use of a basal exemplifier may not result in the correct phylogenetic position of a taxon being recovered if the taxon displays character states more derived than those of the basal exemplifier, and we recommend the use, minimally, of one basal and one derived exemplifier per clade. Paranthodon is most robustly recovered as a stegosaur in our analyses, meaning it is one of the youngest and southernmost stegosaurs.

A new ankylosaurid (Dinosauria: Ankylosauria) from the Lower Cretaceous of China, with comments on ankylosaurian relationships

2001 ◽  
Vol 38 (12) ◽  
pp. 1767-1780 ◽  
Author(s):  
Matthew K Vickaryous ◽  
Anthony P Russell ◽  
Philip J Currie ◽  
Xi-Jin Zhao
Keyword(s):  
Phylogenetic Analysis ◽  
Lower Cretaceous ◽  
Sister Taxon ◽  
Taxonomic Assignment ◽  
Fossil Material ◽  
Preliminary Phylogenetic Analysis

Amongst the fossil material collected by the Sino-Soviet Expeditions (1959–1960) to the Alshan Desert, China, was a large, virtually complete ankylosaur skeleton. Gobisaurus domoculus gen. et sp. nov. closely resembles Shamosaurus scutatus, but is distinct in having an unfused basipterygoid–pterygoid contact and elongate premaxillary processes of the vomers. Although it is difficult to make a definitive taxonomic assignment without considering postcranial material, a preliminary phylogenetic analysis places Gobisaurus as the sister taxon of Shamosaurus, clustered as one of several successive outgroups of the Ankylosaurinae.

scholarly journals Complete Chloroplast Genome of Abutilon fruticosum: Genome Structure, Comparative and Phylogenetic Analysis

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 270
Author(s):  
Dhafer A. Alzahrani
Keyword(s):  
Phylogenetic Analysis ◽  
Chloroplast Genome ◽  
Phylogenetic Analyses ◽  
Genome Structure ◽  
Systematic Position ◽  
Rrna Genes ◽  
Phylogenetic Position ◽  
Trna Genes ◽  
Complete Chloroplast Genome ◽  
The Family

Abutilon fruticosum is one of the endemic plants with high medicinal and economic value in Saudi Arabia and belongs to the family Malvaceae. However, the plastome sequence and phylogenetic position have not been reported until this study. In this research, the complete chloroplast genome of A. fruticosum was sequenced and assembled, and comparative and phylogenetic analyses within the Malvaceae family were conducted. The chloroplast genome (cp genome) has a circular and quadripartite structure with a total length of 160,357 bp and contains 114 unique genes (80 protein-coding genes, 30 tRNA genes and 4 rRNA genes). The repeat analyses indicate that all the types of repeats (palindromic, complement, forward and reverse) were present in the genome, with palindromic occurring more frequently. A total number of 212 microsatellites were identified in the plastome, of which the majority are mononucleotides. Comparative analyses with other species of Malvaceae indicate a high level of resemblance in gene content and structural organization and a significant level of variation in the position of genes in single copy and inverted repeat borders. The analyses also reveal variable hotspots in the genomes that can serve as barcodes and tools for inferring phylogenetic relationships in the family: the regions include trnH-psbA, trnK-rps16, psbI-trnS, atpH-atpI, trnT-trnL, matK, ycf1 and ndhH. Phylogenetic analysis indicates that A. fruticosum is closely related to Althaea officinalis, which disagrees with the previous systematic position of the species. This study provides insights into the systematic position of A. fruticosum and valuable resources for further phylogenetic and evolutionary studies of the species and the Malvaceae family to resolve ambiguous issues within the taxa.

scholarly journals A new iguanodontian (Dinosauria: Ornithopoda) from the Early Cretaceous of Mongolia

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5300
Author(s):  
Terry A. Gates ◽  
Khishigjav Tsogtbaatar ◽  
Lindsay E. Zanno ◽  
Tsogtbaatar Chinzorig ◽  
Mahito Watabe
Keyword(s):  
Phylogenetic Analysis ◽  
Growth Stage ◽  
Phylogenetic Analyses ◽  
Type Specimen ◽  
Sister Taxon ◽  
New Taxon ◽  
Time Of Death ◽  
The North ◽  
Unusual Combination ◽  
Relationship Of

We describe a new iguanodontian ornithopod,Choyrodon barsboldigen. et sp. nov. from the Albian-aged Khuren Dukh Formation of Mongolia based on several partial skeletons interpreted to represent a subadult growth stage based on osteohistological features. This new taxon is diagnosed by many autapomorphies of the maxilla, nasal, lacrimal, opisthotic, predentary, and surangular.Choyrodondisplays an unusual combination of traits, possessing an open antorbital fenestra (a primitive ornithopod trait) together with derived features such as a downturned dentary and enlarged narial fenestra. Histological imaging suggests that the type specimen ofChoyrodonwould have been a subadult at the time of death. Phylogenetic analysis of two different character matrices do not positChoyrodonto be the sister taxon or to be more primitive than the iguanodontianAltirhinus kurzanovi, which is found in the same formation. The only resolved relationship of this new taxon is that it was hypothesized to be a sister-taxon with the North American speciesEolambia caroljonesa. Though discovered in the same formation andChoyrodonbeing smaller-bodied thanAltirhinus, it does not appear that the former species is an ontogimorph of the latter. Differences in morphology and results of the phylogenetic analyses support their distinction although more specimens of both species will allow better refinement of their uniqueness.

scholarly journals A phylogenetic analysis and new delimitation of Crepidiastrum (Asteraceae, tribe Cichorieae)

Phytotaxa ◽  
2014 ◽  
Vol 159 (4) ◽  
pp. 241 ◽  
Author(s):  
Yu-lan Peng ◽  
Yu Zhang ◽  
Xin-fen Gao ◽  
Lin-jing Tong ◽  
Liang Li ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Maximum Likelihood ◽  
Chloroplast Dna ◽  
Maximum Parsimony ◽  
Phylogenetic Analyses ◽  
Systematic Position ◽  
Likelihood Inference ◽  
Nuclear Its ◽  
Chloroplast Dna Regions

The systematic position of Paraixeris humifusa (Asteraceae) is hard to define, because the circumscription of Paraixeris, Youngia and Crepidiastrum, three closely related genera in subtribe Crepidinae (Cichorieae), is not clear. This paper reports on the relationships between 30 species in subtribe Crepidinae, based on an analysis of nucleotides from one nuclear (ITS) and three chloroplast DNA regions ( trnL-F, rps16 and atpB-rbcL). The phylogenetic analyses used maximum parsimony with maximum likelihood inference. The monophyly of Crepidiastrum in the most recent generic classification of Shih & Kilian (2011) is explored. The results show that 12 species in Crepidiastrum constitute a monophyletic group, and that Paraixeris humifusa should be treated as Youngia humifusa.

Synopsis of the Ethmiinae (Lepidoptera, Gelechioidea: Depressariidae) of the Afrotropical Region and descriptions of new species

2014 ◽  
Vol 157 (2-3) ◽  
pp. 105-122
Author(s):  
Wolfram Mey ◽  
Dmitry F. Shovkoon
Keyword(s):  
South Africa ◽  
New Species ◽  
Male Genitalia ◽  
Country Of Origin ◽  
Systematic Position ◽  
Type Material ◽  
Valid Species ◽  
Male And Female ◽  
Line Drawings ◽  
Afrotropical Region

In Africa south of the Sahara 55 valid species of the subfamily Ethmiinae have been recognised to date. These species are listed alphabetically including important synonyms. The country of origin and the depository of the type material are indicated. In this article seven new species are communicated from Kenya, Namibia and South Africa. They are described as Ethmia aberdaresi sp. n., Ethmia anikini sp. n., Ethmia kagamegensis sp. n., Ethmia karasbergensis sp. n., Ethmia kunenica sp. n., Ethmia kuisibi sp. n., and Ethmia fluviatilis sp. n. The adult moths of the new species are illustrated in colour. The male and female genitalia are depicted as black/white photos including line drawings of lateral and dorsal views of male genitalia. The systematic position of the new species is briefly discussed.

scholarly journals Morphology, Morphogenesis, and Molecular Phylogeny of a New Freshwater Ciliate, Quadristicha subtropica n. sp. (Ciliophora, Hypotrichia)

2021 ◽  
Vol 12 ◽  
Author(s):  
Chen Shao ◽  
Qi Gao ◽  
Alan Warren ◽  
Jingyi Wang
Keyword(s):  
Sequence Data ◽  
Southern China ◽  
Phylogenetic Analyses ◽  
Small Subunit ◽  
Systematic Position ◽  
Phylogenetic Position ◽  
Dna Sequence Data ◽  
Freshwater Pond ◽  
Small Subunit Ribosomal Dna

The morphology and the regulation of cortical pattern associated with the cell size, division, and phylogenetic position of a new hypotrichous ciliate, Quadristicha subtropica n. sp. collected from a freshwater pond in southern China, were investigated. Quadristicha subtropica n. sp. is characterized as follows: size in vivo 60–115 μm × 25–45 μm; 19–21 adoral membranelles; buccal cirrus near anterior end of endoral and paroral; cirrus IV/3 at about level of buccal vertex; right marginal row begins ahead of buccal vertex; 11–16 right and 12–19 left marginal cirri; and dorsal cilia about 5 μm long. The basic morphogenetic process in Q. subtropica n. sp. is consistent with that of the type species, Quadristicha setigera. Phylogenetic analyses based on small subunit ribosomal DNA sequence data reveal that the systematic position of Q. subtropica n. sp. is rather unstable with low support values across the tree and the genus Quadristicha is not monophyletic.

scholarly journals A new therocephalian (Gorynychus masyutinae gen. et sp. nov.) from the Permian Kotelnich locality, Kirov Region, Russia

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4933 ◽  
Author(s):  
Christian F. Kammerer ◽  
Vladimir Masyutin
Keyword(s):  
South Africa ◽  
Phylogenetic Analysis ◽  
South African ◽  
Transverse Process ◽  
Sister Taxon ◽  
Dental Morphology ◽  
Late Permian ◽  
Apex Predators ◽  
Global Patterns

A new therocephalian taxon (Gorynychus masyutinae gen. et sp. nov.) is described based on a nearly complete skull and partial postcranium from the Permian Kotelnich locality of Russia. Gorynychus displays an unusual mixture of primitive (“pristerosaurian”) and derived (eutherocephalian) characters. Primitive features of Gorynychus include extensive dentition on the palatal boss and transverse process of the pterygoid, paired vomers, and a prominent dentary angle; derived features include the absence of the postfrontal. Gorynychus can be distinguished from all other therocephalians by its autapomorphic dental morphology, with roughly denticulated incisors and postcanines. Phylogenetic analysis recovers Gorynychus as a non-lycosuchid, non-scylacosaurid therocephalian situated as sister-taxon to Eutherocephalia. The identification of Gorynychus as the largest predator from Kotelnich indicates that therocephalians acted as apex predators in middle–late Permian transition ecosystems in Russia, corroborating a pattern observed in South African faunas. However, other aspects of the Kotelnich fauna, and Permian Russian tetrapod faunas in general, differ markedly from those of South Africa and suggest that Karoo faunas are not necessarily representative of global patterns.

scholarly journals Congruence Between Molecular Data and Morphology: Phylogenetic Position of Senodoniini (Coleoptera: Elateridae)

Insects ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 231 ◽  
Author(s):  
Robin Kundrata ◽  
Alexander S. Prosvirov ◽  
Dominik Vondracek ◽  
Eliska Sormova
Keyword(s):  
Phylogenetic Analysis ◽  
Molecular Markers ◽  
Southeast Asia ◽  
Morphological Characters ◽  
Molecular Data ◽  
Systematic Position ◽  
Phylogenetic Position ◽  
Monotypic Genus ◽  
Click Beetles ◽  
East And Southeast Asia

Senodoniini is a small lineage of click beetles currently comprising 21 species in two genera, distributed in the Himalayas and East and Southeast Asia. The definition and limits of this group have changed considerably during its history. Recent authors treat Senodoniini as a tribe within Dendrometrinae, usually close to Dimini, but this placement has never been rigorously tested. Here, we shed new light on the systematic position and limits of Senodoniini by performing a combined phylogenetic analysis of two nuclear and two mitochondrial molecular markers. Our results recovered Senodoniini not monophyletic, and placed them into the Lissominae complex, where they formed a clade with Austrelater Calder & Lawrence (Protelaterini). Molecular phylogeny is in agreement with the adult morphology. Additionally, we examined the morphology of a monotypic genus Rostricephalus Fleutiaux from Southeast Asia, which was previously classified in various Elateridae groups including Senodoniini, and its position was always uncertain. This genus shares morphological characters with Protelaterini. We provide morphological redescriptions as well as the figures of main diagnostic characters for Senodonia Laporte, Sossor Candèze, and Rostricephalus. Based on our results, we place these genera to Lissominae: Protelaterini, and hence synonymize Senodoniini Schenkling with Protelaterini Schwarz.

The first troglobitic species of Gymnobisiidae (Pseudoscorpiones : Neobisioidea), from Table Mountain (Western Cape Province, South Africa) and its phylogenetic position

2016 ◽  
Vol 30 (1) ◽  
pp. 75 ◽  
Author(s):  
Mark S. Harvey ◽  
Joel A. Huey ◽  
Mia J. Hillyer ◽  
Erin McIntyre ◽  
Gonzalo Giribet
Keyword(s):  
South Africa ◽  
Phylogenetic Analyses ◽  
Mitochondrial Protein ◽  
Strong Support ◽  
Phylogenetic Position ◽  
28S Rrna ◽  
Cave System ◽  
Table Mountain ◽  
The Family ◽  
Afrotropical Region

Fully troglobitic pseudoscorpions are rare in the Afrotropical Region, and we explored the identity and phylogenetic relationships of specimens of a highly modified troglobite of the family Gymnobisiidae in the dark zone of the Wynberg Cave system, on Table Mountain, South Africa. This large pseudoscorpion – described as Gymnobisium inukshuk Harvey & Giribet, sp. nov. – lacks eyes and has extremely long appendages, and has been found together with other troglobitic fauna endemic only to this cave system. Phylogenetic analyses using the nuclear ribosomal genes 18S rRNA and 28S rRNA and the mitochondrial protein-encoding gene cytochrome c oxidase subunit I unambiguously place the new species with other surface Gymnobisium from South Africa. This placement receives strong support and is stable to analytical treatments, including static and dynamic homology, parsimony and maximum likelihood, and data removal for ambiguously aligned sites. This species is the first troglobitic species of the family and one of the most highly modified pseudoscorpions from the Afrotropical Region. http://zoobank.org/urn:lsid:zoobank.org:pub:5227092B-A64B-4DB3-AD90-F474F0BA6AED

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