scholarly journals Robust phylogenetic position of the enigmatic hydrozoan, Margelopsis haeckelii revealed within the family Corymorphidae

2021 ◽  
Author(s):  
Daria M. Kupaeva ◽  
Tatiana S. Lebedeva ◽  
Tatiana P. Ashurkova ◽  
Andrey A. Prudkovsky ◽  
Daniel Vanwalleghem ◽  
...  
Keyword(s):  
18S Rrna ◽  
Phylogenetic Signal ◽  
Sister Group ◽  
Molecular Study ◽  
Phylogenetic Position ◽  
28S Rrna ◽  
Recent Molecular Study ◽  
The Family ◽  
Molecular Phylogenetic ◽  
Multigene Analyses

The life-cycle and polyp morphology of Margelopsidae representatives are very different from all other Aplanulata cnidarians. Until recently, their evolutionary origin and phylogenetic position has been a subject of significant speculation. A recent molecular study based only on COI data unexpectedly placed Margelopsidae as a sister group to all Aplanulata, despite the Margelopsid morphology suggests affiliation with Tubulariidae or Corymorphidae. Here we used multigene analyses, including nuclear (18S rRNA and 28S rRNA) and mitochondrial (16S rRNA and COI) markers of the Margelopsidae hydroid Margelopsis haeckelii Hartlaub, 1897, to resolve its phylogenetic position with respect to other hydrozoans. Our data provides strong evidence that M. haeckelii is a member of the family Corymorphydae, making the family Margelopsidae invalid. Furthermore, we show that medusa previously known as M. harlaubii Browne, 1903 is sister to Plotocnide borealis, Wagner, 1885 and might be a member of Boreohydridae. The phylogenetic signal of polyp and medusа stages is discussed in light of concept of inconsistent evolution and molecular phylogenetic analysis.

A molecular phylogeny of the circum-Antarctic Opiliones family Neopilionidae

2021 ◽  
Author(s):  
Gonzalo Giribet ◽  
Kate Sheridan ◽  
Caitlin M. Baker ◽  
Christina J. Painting ◽  
Gregory I. Holwell ◽  
...  
Keyword(s):  
New Zealand ◽  
South America ◽  
Morphological Study ◽  
18S Rrna ◽  
New Caledonia ◽  
Sister Group ◽  
28S Rrna ◽  
South American ◽  
Australian Species ◽  
The Family

The Opiliones family Neopilionidae is restricted to the terranes of the former temperate Gondwana: South America, Africa, Australia, New Caledonia and New Zealand. Despite decades of morphological study of this unique fauna, it has been difficult reconciling the classic species of the group (some described over a century ago) with recent cladistic morphological work and previous molecular work. Here we attempted to investigate the pattern and timing of diversification of Neopilionidae by sampling across the distribution range of the family and sequencing three markers commonly used in Sanger-based approaches (18S rRNA, 28S rRNA and cytochrome-c oxidase subunit I). We recovered a well-supported and stable clade including Ballarra (an Australian ballarrine) and the Enantiobuninae from South America, Australia, New Caledonia and New Zealand, but excluding Vibone (a ballarrine from South Africa). We further found a division between West and East Gondwana, with the South American Thrasychirus/Thrasychiroides always being sister group to an Australian–Zealandian (i.e. Australia + New Zealand + New Caledonia) clade. Resolution of the Australian–Zealandian taxa was analysis-dependent, but some analyses found Martensopsalis, from New Caledonia, as the sister group to an Australian–New Zealand clade. Likewise, the species from New Zealand formed a clade in some analyses, but Mangatangi often came out as a separate lineage from the remaining species. However, the Australian taxa never constituted a monophyletic group, with Ballarra always segregating from the remaining Australian species, which in turn constituted 1–3 clades, depending on the analysis. Our results identify several generic inconsistencies, including the possibility of Thrasychiroides nested within Thrasychirus, Forsteropsalis being paraphyletic with respect to Pantopsalis, and multiple lineages of Megalopsalis in Australia. In addition, the New Zealand Megalopsalis need generic reassignment: Megalopsalis triascuta will require its own genus and M. turneri is here transferred to Forsteropsalis, as Forsteropsalis turneri (Marples, 1944), comb. nov.

Prosogynopora riseri, gen. et sp. nov., a phylogenetically problematic lithophoran proseriate (Platyhelminthes : Rhabditophora) with inverted genital pores from the New England coast

2014 ◽  
Vol 28 (3) ◽  
pp. 309 ◽  
Author(s):  
Christopher E. Laumer ◽  
Gonzalo Giribet ◽  
Marco Curini-Galletti
Keyword(s):  
New England ◽  
Sister Group ◽  
Optimality Criteria ◽  
Phylogenetic Position ◽  
28S Rrna ◽  
New Taxon ◽  
Taxonomic Rank ◽  
Molecular Phylogenetic ◽  
Pore Opening ◽  
Group Relationships

A new lithophoran proseriate flatworm, Prosogynopora riseri, gen. et sp. nov. (Platyhelminthes: Rhabditophora: Proseriata), is described from the New England coast (USA). The species shares characters with members of the families Calviriidae and Coelogynoporidae, e.g. the presence of paracnida, the short common female duct, a septum and diaphragm at the base of the pharynx. However, the inverted topology of the genital system, presenting an anterior female pore shortly behind the mouth and a male pore opening nearly on the caudal terminus, is unique within the Proseriata, and permits inclusion into neither family on morphological grounds. We investigated the phylogenetic position of the new species within the available diversity of proseriate 18S and 28S rRNA sequences. However, an exploration of diverse homology schemes, alignment conditions and optimality criteria proved the position of P. riseri, gen. et sp. nov. to be remarkably unstable, particularly with respect to the method of alignment, variously suggesting sister-group relationships with (or within) Coelogynoporidae, with Calviriidae, or with a clade composed of all other Lithophora. Despite its unique morphology and the absence of molecular phylogenetic evidence for its inclusion within any family as currently defined, we refrain from assigning a higher taxonomic rank to the new lineage, pending critical re-assessment of homology in several character systems and the availability of further taxon- and gene-rich enquiries into the phylogeny of Proseriata. Apingospermata, new taxon and Dolichogynoducta, new taxon are proposed as two rankless taxonomic names of Lithophora, corresponding to well-supported clades in our molecular phylogenetic hypothesis.

An opisthorchiid concept of the genus Liliatrema (Trematoda: Plagiorchiida: Opisthorchioidea): an unexpected systematic position

2020 ◽  
Author(s):  
Sergey Sokolov ◽  
Evgeniy Frolov ◽  
Semen Novokreshchennykh ◽  
Dmitry Atopkin
Keyword(s):  
Phylogenetic Analyses ◽  
Sister Group ◽  
Systematic Position ◽  
Phylogenetic Position ◽  
Rrna Gene ◽  
28S Rrna ◽  
The Family ◽  
Using Data ◽  
Terminal Genitalia ◽  
Rdna Analysis

Abstract Liliatrema is a small genus of trematodes consisting of two species. Its systematic position has long been debated, partly because of the confusing reports about the structure of male terminal genitalia. Here we test the phylogenetic position of the genus Liliatrema using data on complete 18S rRNA and partial 28S rRNA gene sequences obtained for Liliatrema skrjabini. We also provide a detailed description of terminal genitalia in adult specimens of L. sobolevi and metacercariae of both Liliatrema species. The results of the 28S rDNA-based phylogenetic analysis indicate that Liliatrema falls within a well-supported clade, which also includes Apophallus and traditional opisthorchiids. This clade, in turn, is nested within a well-supported clade, containing Euryhelmis, Cryptocotyle and Scaphanocephalus. In the 18S+8S rDNA analysis, Liliatrema appears as a sister-taxon to the Cryptocotyle + Euryhelmis group. The Liliatrema + (Cryptocotyle + Euryhelmis) clade is a well-supported sister-group to the traditional opisthorchiids. The morphology of the terminal genitalia of the liliatrematids also corresponds to that of the opisthorchioids. Thus, the results of our morphological and phylogenetic analyses favour an unexpected conclusion that the genus Liliatrema belongs to the Opisthorchioidea. We propose that the genera Liliatrema, Apophallus, Euryhelmis, Cryptocotyle and Scaphanocephalus belong, respectively, within the subfamilies Liliatrematinae, Apophallinae, Euryhelminthinae and Cryptocotylinae of the family Opisthorchiidae.

An integrative description of a new Cephalothrix species (Nemertea: Palaeonemertea) from the South China Sea

Zootaxa ◽  
2021 ◽  
Vol 4908 (4) ◽  
pp. 584-594
Author(s):  
ALEXEI V. CHERNYSHEV ◽  
NEONILA E. POLYAKOVA
Keyword(s):  
Laser Scanning ◽  
18S Rrna ◽  
Laser Scanning Microscopy ◽  
Colour Pattern ◽  
Confocal Laser ◽  
28S Rrna ◽  
Body Colour ◽  
Mitochondrial Coi ◽  
The Family ◽  
Molecular Phylogenetic

A new nemertean species of the genus Cephalothrix from intertidal calcareous red algae off the Vietnam coast is described based on histological sections, confocal laser scanning microscopy, and nucleotide sequences of three nuclear (18S rRNA, 28S rRNA, H3) and two mitochondrial (COI, 16S rRNA) DNA fragments. Cephalothrix suni sp. nov. is characterized by a unique body colour pattern consisting of transverse brown on ventral body side. A molecular phylogenetic analysis of the family Cephalotrichidae using a multigene approach has identified three clades for Cephalothrix: Cephalothrix, Procephalothrix, and interstitial cephalotrichids. The new species belongs to clade Procephalothrix sensu Chernyshev & Kajihara 2019 and a subclade of species with red, orange, or dark yellow anterior tip. 

scholarly journals New insights into the phylogeny, systematics and DNA barcoding of Nemertea

2014 ◽  
Vol 28 (3) ◽  
pp. 287 ◽  
Author(s):  
Sebastian Kvist ◽  
Christopher E. Laumer ◽  
Juan Junoy ◽  
Gonzalo Giribet
Keyword(s):  
Dna Barcoding ◽  
18S Rrna ◽  
Phylogenetic Analyses ◽  
Sister Group ◽  
28S Rrna ◽  
Variable Regions ◽  
Molecular Phylogenetic ◽  
Coi Sequences ◽  
Length Variable ◽  
High Support

Although some clades of ribbon worms (phylum Nemertea) are consistently recovered with high support in molecular phylogenies, the placement and inter-relationships of some taxa have proven problematic. Herein, we performed molecular phylogenetic analyses aimed at resolving these recalcitrant splits, using six loci (nuclear 18S rRNA, 28S rRNA, histones H3 and H4, and mitochondrial 16S rRNA and COI) for 133 terminals, with particular emphasis on the problematic families Hubrechtidae and Plectonemertidae. Three different datasets were used for phylogenetic analyses and both maximum likelihood and maximum parsimony methodologies were applied. All but one of the resulting tree topologies agree on the paraphyly of the class Palaeonemertea, whereas Heteronemertea, Hoplonemertea, Polystilifera, Monostilifera and Hubrechtidae are always recovered as reciprocally monophyletic. Hubrechtidae is sister group to Heteronemertea (the Pilidiophora hypothesis) only when length variable regions of 18S rRNA and 28S rRNA are excluded. Moreover, the terrestrial and freshwater family Plectonemertidae is recovered with high support and the implications of this finding are further discussed. Finally, we evaluate the utility of DNA barcoding for specimen identification within Nemertea using an extended dataset containing 394 COI sequences. Results suggest that DNA barcoding may work for Nemertea, insofar as a distinct barcoding gap (the gap between the maximum intraspecific variation and the minimum interspecific divergence) may exist, but its recognition is regularly hampered by low accuracy in species level identifications.

scholarly journals Importance of the postcranial skeleton in eusuchian phylogeny: Reassessing the systematics of allodaposuchid crocodylians

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0251900
Author(s):  
Alejandro Blanco
Keyword(s):  
Current Knowledge ◽  
Phylogenetic Signal ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Postcranial Skeleton ◽  
Skull Morphology ◽  
Taxonomic Descriptions ◽  
The Family ◽  
Phylogenetic Hypotheses ◽  
Internal Relationships

Our current knowledge on the crocodyliform evolution is strongly biased towards the skull morphology, and the postcranial skeleton is usually neglected in many taxonomic descriptions. However, it is logical to expect that it can contribute with its own phylogenetic signal. In this paper, the changes in the tree topology caused by the addition of the postcranial information are analysed for the family Allodaposuchidae, the most representative eusuchians in the latest Cretaceous of Europe. At present, different phylogenetic hypotheses have been proposed for this group without reaching a consensus. The results of this paper evidence a shift in the phylogenetic position when the postcranium is included in the dataset, pointing to a relevant phylogenetic signal in the postcranial elements. Finally, the phylogenetic relationships of allodaposuchids within Eusuchia are reassessed; and the internal relationships within Allodaposuchidae are also reconsidered after an exhaustive revision of the morphological data. New and improved diagnoses for each species are here provided.

scholarly journals A fresh look at Cladarosymblema narrienense, a tetrapodomorph fish (Sarcopterygii: Megalichthyidae) from the Carboniferous of Australia, illuminated via X-ray tomography

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12597
Author(s):  
Alice M. Clement ◽  
Richard Cloutier ◽  
Jing Lu ◽  
Egon Perilli ◽  
Anton Maksimenko ◽  
...  
Keyword(s):  
Original Description ◽  
Sister Group ◽  
Axial Skeleton ◽  
Phylogenetic Position ◽  
Micro Computed Tomography ◽  
Holotype Specimen ◽  
Freshwater Swamp ◽  
The Family ◽  
First Time ◽  
Detailed Work

Background The megalichthyids are one of several clades of extinct tetrapodomorph fish that lived throughout the Devonian–Permian periods. They are advanced “osteolepidid-grade” fishes that lived in freshwater swamp and lake environments, with some taxa growing to very large sizes. They bear cosmine-covered bones and a large premaxillary tusk that lies lingually to a row of small teeth. Diagnosis of the family remains controversial with various authors revising it several times in recent works. There are fewer than 10 genera known globally, and only one member definitively identified from Gondwana. Cladarosymblema narrienense Fox et al. 1995 was described from the Lower Carboniferous Raymond Formation in Queensland, Australia, on the basis of several well-preserved specimens. Despite this detailed work, several aspects of its anatomy remain undescribed. Methods Two especially well-preserved 3D fossils of Cladarosymblema narrienense, including the holotype specimen, are scanned using synchrotron or micro-computed tomography (µCT), and 3D modelled using specialist segmentation and visualisation software. New anatomical detail, in particular internal anatomy, is revealed for the first time in this taxon. A novel phylogenetic matrix, adapted from other recent work on tetrapodomorphs, is used to clarify the interrelationships of the megalichthyids and confirm the phylogenetic position of C. narrienense. Results Never before seen morphological details of the palate, hyoid arch, basibranchial skeleton, pectoral girdle and axial skeleton are revealed and described. Several additional features are confirmed or updated from the original description. Moreover, the first full, virtual cranial endocast of any tetrapodomorph fish is presented and described, giving insight into the early neural adaptations in this group. Phylogenetic analysis confirms the monophyly of the Megalichthyidae with seven genera included (Askerichthys, Cladarosymblema, Ectosteorhachis, Mahalalepis, Megalichthys, Palatinichthys, and Sengoerichthys). The position of the megalichthyids as sister group to canowindrids, crownward of “osteolepidids” (e.g.,Osteolepis and Gogonasus), but below “tristichopterids” such as Eusthenopteron is confirmed, but our findings suggest further work is required to resolve megalichthyid interrelationships.

The Phylogenetic Position of Crenea in the Lythraceae Based on Molecular Evidence, and the Transfer of Its Two Species to Ammannia

2021 ◽  
Vol 106 ◽  
pp. 325-339
Author(s):  
Shirley A. Graham ◽  
Peter W. Inglis ◽  
Taciana B. Cavalcanti
Keyword(s):  
Morphological Character ◽  
Phylogenetic Analyses ◽  
Taxonomic Status ◽  
Phylogenetic Position ◽  
Molecular Evidence ◽  
Monophyletic Lineage ◽  
The Family ◽  
Mangrove Vegetation ◽  
Molecular Phylogenetic ◽  
Globally Distributed

Crenea Aubl. (Lythraceae) is a ditypic genus of subshrubs occurring in mangrove vegetation on the coasts of northern South America. Phylogenetic analyses based on morphology have offered unresolved and conflicting phylogenetic positions for the genus in the family. This study presents the first molecular sequences for Crenea, from nrITS, rbcL, trnL, trnL-F, and matK regions. Molecular phylogenetic analyses find full support for Crenea within Ammannia L., a relationship not previously recognized. Ammannia is a globally distributed genus of terrestrial to amphibious herbs mostly occurring in freshwater marshes and wetlands. It was recently reconfigured based on phylogenetic evidence to include the genera Nesaea Comm. ex Kunth and Hionanthera A. Fern. & Diniz. The transfer of Crenea to Ammannia further extends the morphological, ecological, and biogeographical diversity of Ammannia and provides the final evidence defining Ammannia as a monophyletic lineage of the Lythraceae. A revised circumscription of Ammannia s.l. adds several new morphological character states and the first species in the genus restricted to mangrove vegetation. Two changes in taxonomic status are made: Ammannia maritima (Aubl.) S. A. Graham, P. W. Inglis, & T. B. Cavalc., comb. nov., and Ammannia patentinervius (Koehne) S. A. Graham, P. W. Inglis, & T. B. Cavalc., comb. nov. The new combinations are described, a list of exsiccatae examined is provided, and the effects of the reconfiguration to the morphology and biogeography of the genus are detailed.

scholarly journals Phylogenetic position and taxonomy of Cycloseris explanulata and C. wellsi (Scleractinia: Fungiidae): lost mushroom corals find their way home

2012 ◽  
Vol 81 (3) ◽  
pp. 125-146 ◽  
Author(s):  
Francesca Benzoni ◽  
Roberto Arrigoni ◽  
Fabrizio Stefani ◽  
Bastian T. Reijnen ◽  
Simone Montano ◽  
...  
Keyword(s):  
Molecular Study ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Distribution Data ◽  
Data Sets ◽  
Free Living ◽  
New Findings ◽  
The Family ◽  
Ecological Implications ◽  
History Of

The scleractinian species Psammocora explanulata and Coscinaraea wellsi were originally classified in the family Siderastreidae, but in a recent morpho-molecular study it appeared that they are more closely related to each other and to the Fungiidae than to any siderastreid taxon. A subsequent morpho-molecular study of the Fungiidae provided new insights regarding the phylogenetic relationships within that family. In the present study existing molecular data sets of both families were analyzed jointly with those of new specimens and sequences of P. explanulata and C. wellsi. The results indicate that both species actually belong to the Cycloseris clade within the family Fungiidae. A reappraisal of their morphologic characters based on museum specimens and recently collected material substantiate the molecular results. Consequently, they are renamed Cycloseris explanulata and C. wellsi. They are polystomatous and encrusting like C. mokai, another species recently added to the genus, whereas all Cycloseris species were initially thought to be monostomatous and free-living. In the light of the new findings, the taxonomy and distribution data of C. explanulata and C. wellsi have been updated and revised. Finally, the ecological implications of the evolutionary history of the three encrusting polystomatous Cycloseris species and their free-living monostomatous congeners are discussed.

scholarly journals Phylogeny and morphology of genus Nephrocytium (Sphaeropleales, Chlorophyceae, Chlorophyta) from China

Phytotaxa ◽  
2017 ◽  
Vol 319 (1) ◽  
pp. 84 ◽  
Author(s):  
XUDONG LIU ◽  
HUAN ZHU ◽  
BENWEN LIU ◽  
GUOXIANG LIU ◽  
ZHENGYU HU
Keyword(s):  
Phylogenetic Analyses ◽  
Light And Electron Microscopy ◽  
Taxonomic Position ◽  
Phylogenetic Position ◽  
Phytoplankton Communities ◽  
Close Phylogenetic Relationship ◽  
The Family ◽  
Close Relationship ◽  
Molecular Phylogenetic

The genus Nephrocytium Nägeli is a common member of phytoplankton communities that has a distinctive morphology. Its taxonomic position is traditionally considered to be within the family Oocystaceae (Trebouxiophyceae). However, research on its ultrastructure is rare, and the phylogenetic position has not yet been determined. In this study, two strains of Nephrocytium, N. agardhianum Nägeli and N. limneticum (G.M.Smith) G.M.Smith, were identified and successfully cultured in the laboratory. Morphological inspection by light and electron microscopy and molecular phylogenetic analyses were performed to explore the taxonomic position. Ultrastructure implied a likely irregular network of dense and fine ribs on the surface of the daughter cell wall that resembled that of the genus Chromochloris Kol & Chodat (Chromochloridaceae). Phylogenetic analyses revealed that Nephrocytium formed an independent lineage in the order Sphaeropleales (Chlorophyceae) with high support values and a close phylogenetic relationship with Chromochloris. Based on combined morphological, ultrastructural and phylogenetic data, we propose a re-classification of Nephrocytium into Sphaeropleales, sharing a close relationship with Chromochloris.

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