Time calibrated morpho-molecular classification of Nassellaria (Radiolaria)

AbstractNassellaria are marine radiolarian protists belonging to the Rhizaria lineage. Their skeleton, made of opaline silica, exhibit an excellent fossil record, extremely valuable in micro-paleontological studies for paleo-environmental reconstruction. Yet, to date very little is known about the extant diversity and ecology of Nassellaria in contemporary oceans, and most of it is inferred from their fossil record. Here we present an integrative classification of Nassellaria based on taxonomical marker genes (18S and 28S ribosomal DNA) and morphological characteristics obtained by optical and scanning electron microscopy imaging. Our phylogenetic analyses distinguished 11 main morpho-molecular clades relying essentially on the overall morphology of the skeleton and not on internal structures as previously considered. Using fossil calibrated molecular clock we estimated the origin of Nassellaria among radiolarians primitive forms in the Devonian (ca. 420 Ma), that gave rise to living nassellarian groups in the Triassic (ca. 250 Ma), during the biggest diversification event over their evolutionary history. This morpho-molecular framework provides both a new morphological classification easier to identify under light microscopy and the basis for future molecular ecology surveys. Altogether, it brings a new standpoint to improve our scarce understanding of the ecology and worldwide distribution of extant nassellarians.

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Phylogenetic taxonomy and classification of the Crinoidea (Echinodermata)

Journal of Paleontology ◽

10.1017/jpa.2016.142 ◽

2017 ◽

Vol 91 (4) ◽

pp. 829-846 ◽

Cited By ~ 38

Author(s):

David F. Wright ◽

William I. Ausich ◽

Selina R. Cole ◽

Mark E. Peter ◽

Elizabeth C. Rhenberg

Keyword(s):

Phylogenetic Relationships ◽

Fossil Record ◽

Phylogenetic Analyses ◽

Major Goal ◽

Evolutionary Patterns ◽

Phylogenetic Taxonomy ◽

Phylogenetic Perspective ◽

Phylogenetic Hypotheses ◽

Patterns And Processes

AbstractA major goal of biological classification is to provide a system that conveys phylogenetic relationships while facilitating lucid communication among researchers. Phylogenetic taxonomy is a useful framework for defining clades and delineating their taxonomic content according to well-supported phylogenetic hypotheses. The Crinoidea (Echinodermata) is one of the five major clades of living echinoderms and has a rich fossil record spanning nearly a half billion years. Using principles of phylogenetic taxonomy and recent phylogenetic analyses, we provide the first phylogeny-based definition for the Clade Crinoidea and its constituent subclades. A series of stem- and node-based definitions are provided for all major taxa traditionally recognized within the Crinoidea, including the Camerata, Disparida, Hybocrinida, Cladida, Flexibilia, and Articulata. Following recommendations proposed in recent revisions, we recognize several new clades, including the Eucamerata Cole 2017, Porocrinoidea Wright 2017, and Eucladida Wright 2017. In addition, recent phylogenetic analyses support the resurrection of two names previously abandoned in the crinoid taxonomic literature: the Pentacrinoidea Jaekel, 1918 and Inadunata Wachsmuth and Springer, 1885. Last, a phylogenetic perspective is used to inform a comprehensive revision of the traditional rank-based classification. Although an attempt was made to minimize changes to the rank-based system, numerous changes were necessary in some cases to achieve monophyly. These phylogeny-based classifications provide a useful template for paleontologists, biologists, and non-experts alike to better explore evolutionary patterns and processes with fossil and living crinoids.

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A new predatory leech from Vietnam (Hirudinida : Arhynchobdellida : Salifidae): its phylogenetic position with comments on the classification of the family

Invertebrate Systematics ◽

10.1071/is15008 ◽

2015 ◽

Vol 29 (5) ◽

pp. 473 ◽

Cited By ~ 1

Author(s):

Takafumi Nakano ◽

Son Truong Nguyen

Keyword(s):

Phylogenetic Relationships ◽

Phylogenetic Analyses ◽

Morphological Characteristics ◽

Molecular Data ◽

Phylogenetic Position ◽

12S Rrna ◽

The Family ◽

Morphological And Molecular Data ◽

First Time

The family Salifidae is a predaceous leech taxon in the suborder Erpobdelliformes. Although Salifidae is widely distributed in the African, Oriental, Indo-Malayan, Sino-Japanese and Australasian regions, the phylogenetic relationships of the family Salifidae have never been tested using molecular data obtained from leeches collected from the family distributional range. A salifid species was collected for the first time in Vietnam, and relevant morphological and molecular data are presented here. Because the Vietnamese salifid species possesses unique morphological characteristics among the known salifid species, this species is herein described as a new species, Salifa motokawai, sp. nov. Phylogenetic analyses based on nuclear 18S rRNA and histone H3, as well as mitochondrial cytochrome c oxidase subunit I, tRNACys, tRNAMet, 12S rRNA, tRNAVal, 16S rRNA, tRNALeu and NADH dehydrogenase subunit 1 markers demonstrate that the Vietnamese salifid species is a close congener with the African Salifa perspicax and the Malagasy Linta be. Furthermore, molecular data revealed non-monophyly of the Asian salifid leeches. According to the observed phylogenetic relationships and morphological characteristics of the Vietnamese Salifa motokawai, sp. nov., the current classification of salifid taxa should be revised.

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A barcoding approach to phylogenetic classification of Aedini mosquitoes (Aedes, Ochlerotatus)

10.1101/285825 ◽

2018 ◽

Author(s):

H. Glass ◽

E. Carroll ◽

D. Curley ◽

H. Kienzle ◽

D. A. Yee ◽

...

Keyword(s):

Genetic Markers ◽

Genetic Relatedness ◽

Phylogenetic Analyses ◽

Morphological Characteristics ◽

Insufficient Evidence ◽

Phylogenetic Classification ◽

Genetic Barcoding

AbstractTraditionally, entomologists have used morphological characteristics for mosquito taxonomy and systematics. However, this approach does not take into consideration the genetic relatedness of species. In 2000, the Aedes genus of mosquitoes in the tribe Aedini was split into two genera (Aedes and Ochlerotatus), thereby elevating Ochlerotatus from subgenus to genus rank, strictly based on morphology of adults. Herein, we use the genetic barcoding marker COI to generate a phylogeny of 65 species of Aedes, Ochlerotatus, and Anopheles outgroup from almost 900 sequences downloaded from BOLD systems. Our results reveal evidence of non-random, but polyphyletic clustering of Aedes and Ochlerotatus species, with a monophyletic outgroup. We do find support for the validity of Ochlerotatus as an evolutionary unit, although we find insufficient evidence to support its retention as a genus. We suggest that mosquito phylogenetic analyses incorporate a greater number of genetic markers to help clarify our understanding of Aedini species classifications, but caution that recent assessments based solely on morphology may be insufficient.

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Morpho-molecular diversity and evolutionary analyses suggest hidden life styles in Spumellaria (Radiolaria)

10.1101/2020.06.29.176917 ◽

2020 ◽

Author(s):

Miguel M. Sandin ◽

Tristan Biard ◽

Sarah Romac ◽

Luis O’Dogherty ◽

Noritoshi Suzuki ◽

...

Keyword(s):

Fossil Record ◽

Morphological Characteristics ◽

Radial Symmetry ◽

Global Ocean ◽

Marker Genes ◽

Environmental Reconstruction ◽

Taxonomic Rank ◽

Middle Cambrian ◽

Life Styles ◽

Comprehensive Classification

AbstractSpumellaria (Radiolaria, Rhizaria) are holoplanktonic amoeboid protists, ubiquitous and abundant in the global ocean. Their silicified skeleton preserves very well in sediments displaying an excellent fossil record, from the early middle Cambrian (ca. 509-521 Ma), extremely valuable for paleo-environmental reconstruction studies. Spumellaria are tedious to maintain in laboratory conditions preventing an accurate perception of their extant diversity and ecology in today’s oceans, most of which being inferred from sediment records. This study represents an integrated and comprehensive classification of Spumellaria based on the combination of ribosomal taxonomic marker genes (rDNA) and morphological characteristics. In contrast to established taxonomic knowledge, we demonstrate that symmetry of the skeleton takes more importance than internal structures at high taxonomic rank classification. Such reconsideration allows gathering different morphologies with concentric structure and a spherical or radial symmetry believed to belong to other Radiolaria orders from the fossil record, as for some Entactinaria families. Results obtained in this study suggest the existence of new Spumellaria diversity at early diverging positions, in which a non-bearing skeleton organism lives within shelled ones. Using fossil calibrated molecular clock we estimated the origin of Spumellaria in the middle Cambrian (ca. 515 Ma), in agreement with the appearance of the first radiolarian representatives in the fossil record. The morpho-molecular and evolutionary framework established herein allows a direct connection between living specimens and fossil morphologies from the Cambrian, bringing both a standpoint for future molecular environmental surveys and a better understanding for paleo-environmental reconstruction studies.

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Phylogeny and classification of the genus-group taxa of Loxandrina (Coleoptera, Carabidae, Abacetini)

Deutsche Entomologische Zeitschrift ◽

10.3897/dez.67.55985 ◽

2020 ◽

Vol 67 (2) ◽

pp. 151-182

Author(s):

Kipling Will

Keyword(s):

North American ◽

Phylogenetic Relationships ◽

Phylogenetic Analyses ◽

Morphological Characteristics ◽

Historical Biogeography ◽

North American Species ◽

Diagnostic Features ◽

Genus Level

Bayesian and parsimony phylogenetic analyses of combined and partitioned datasets of molecular (partial sequences of 28S, wg, COI, and CAD) and morphological (51 characters of adults) data for exemplar taxa of five outgroup and 76 ingroup abacetine carabids resulted in a monophyletic Loxandrina Erwin & Sims, 1984 that is split into Australian and American clades. The genus Loxandrus LeConte, 1853 as previously delimited is not monophyletic relative to numerous genus-level taxa in Abacetini Chaudoir, 1873 and is restricted to a subgenus of North American species. A reclassification and nomenclatural changes for the subtribe that are consistent with the phylogeny are provided. Three genera are removed from Loxandrina: Aulacopodus Britton, 1940 moved to Pterostichini Bonelli, 1810; Cosmodiscus Sloane, 1907 and Tiferonia Darlington, 1962 moved to Abacetina. Based on the phylogenetic relationships and nomenclatural priority only four genera are recognized in Loxandrina: Cerabilia Laporte, 1867, Zeodera Laporte, 1867, Pediomorphus Chaudoir, 1878, and Oxycrepis Reiche, 1843. All other previously recognized genera are treated as subgenera. The classification change created eight secondary homonyms that are resolved by the proposal of the following: Oxycrepis gebi, replacement name for O. balli (Straneo, 1993); O. amatona, replacement name for O. matoana (Straneo, 1993); O. xiproma, replacement name for O. proxima (Straneo, 1993); O. rasutulis, replacement name for O. suturalis (Straneo, 1993); O. laevinota, replacement name for O. laevicollis (Bates, 1871); O. arvulap, replacement name for O. parvula (Straneo, 1951); O. noaffine, replacement name for O. affinis (Straneo, 1991); O. alutona, replacement name for O. notula (Tschitschérine, 1901). An overview of the morphological characteristics and diagnostic features of Loxandrina taxa is provided. A key and habitus images are provided for identification of genera and subgenera. The possible historical biogeography of the group is discussed in light of their phylogenetic relationships and past geological events.

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Phylogenetic Classification of Subtribe Castillejinae (Orobanchaceae)

Systematic Botany ◽

10.1600/036364409787602357 ◽

2009 ◽

Vol 34 (1) ◽

pp. 182-197 ◽

Cited By ~ 15

Author(s):

David C. Tank ◽

J. Mark Egger ◽

Richard G. Olmstead

Keyword(s):

Phylogenetic Analyses ◽

Morphological Characteristics ◽

Systematic Research ◽

New Combinations ◽

Phylogenetic Hypothesis ◽

Molecular Systematic ◽

Genus Level ◽

Formal Classification ◽

Molecular Phylogenetic

Recent molecular systematic research has indicated the need for a revised circumscription of generic boundaries in subtribe Castillejinae (tribe Pedicularideae, Orobanchaceae). Based on a well-resolved and well-supported phylogenetic hypothesis, we present a formal reclassification of the major lineages comprising the Castillejinae. Prior to this treatment, subtribe Castillejinae included Castilleja (ca. 190 spp.), Cordylanthus (18 spp.), Orthocarpus (9 spp.), Triphysaria (5 spp.), and the monotypic genera Clevelandia and Ophiocephalus. In the classification presented here, Orthocarpus and Triphysaria retain their current circumscriptions, Castilleja is expanded to include Clevelandia and Ophiocephalus, and Cordylanthus is split into three genera; a key to the genera as they are recognized here is provided. Two new combinations, Castilleja beldingii and Castilleja ophiocephala, are proposed within the expanded Castilleja. The concept of Cordylanthus is restricted to the 13 species formerly recognized as subg. Cordylanthus, while subg. Dicranostegia and subg. Hemistegia are elevated to genus level (Dicranostegia and Chloropyron, respectively). We resurrect the generic name Chloropyron for the halophytes previously recognized as subg. Hemistegia. Five new combinations are proposed for Chloropyron (Chloropyron maritimum subsp. canescens, Chloropyron maritimum subsp. palustre, Chloropyron molle subsp. hispidum, Chloropyron palmatum, and Chloropyron tecopense). In addition to the formal classification, we provide phylogenetic clade definitions for Castillejinae, each of the genera, and two additional clades that are not assigned formal ranks. Morphological characteristics used to recognize traditional groups are evaluated, and synapomorphies are discussed. Finally, the current infrageneric classifications for Castilleja and Cordylanthus are evaluated in light of the recent molecular phylogenetic analyses.

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RHYNCHOLITES AND THE PROBLEM OF NARROW AND BROAD CONCEPTION OF TAXONS

Proceedings of higher educational establishments Geology and Exploration ◽

10.32454/0016-7762-2018-1-12-17 ◽

2018 ◽

pp. 12-17 ◽

Cited By ~ 3

Author(s):

I. R. Khuzina ◽

V. N. Komarov

Keyword(s):

Sexual Dimorphism ◽

Morphological Characteristics ◽

Mass Scale ◽

Individual Variability ◽

Point Of View ◽

The Other ◽

New Taxon ◽

Artificial System ◽

Broad Understanding

The paper considers a point of view, based on the conception of the broad understanding of taxons. According to this point of view, rhyncholites of the subgenus Dentatobeccus and Microbeccus are accepted to be synonymous with the genus Rhynchoteuthis, and subgenus Romanovichella is considered to be synonymous with the genus Palaeoteuthis. The criteria, exercising influence on the different approaches to the classification of rhyncholites, have been analyzed (such as age and individual variability, sexual dimorphism, pathological and teratological features, degree of disintegration of material), underestimation of which can lead to inaccuracy. Divestment of the subgenuses Dentatobeccus, Microbeccus and Romanovichella, possessing very bright morphological characteristics, to have an independent status and denomination to their synonyms, has been noted to be unjustified. An artificial system (any suggested variant) with all its minuses is a single probable system for rhyncholites. The main criteria, minimizing its negative sides and proving the separation of the new taxon, is an available mass-scale material. The narrow understanding of the genus, used in sensible limits, has been underlined to simplify the problem of the passing the view about the genus to the other investigators and recognition of rhyncholites for the practical tasks.

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The excavation of a medieval ring-ditch enclosure at Hayknowes Farm, Annan, Dumfries and Galloway

Scottish Archaeological Journal ◽

10.3366/saj.2001.23.2.119 ◽

2001 ◽

Vol 23 (2) ◽

pp. 119-139

Author(s):

R. A. GREGORY ◽

D. W. HALL ◽

D. W. SHIMWELL

Keyword(s):

Radiocarbon Dating ◽

Structural Phase ◽

Morphological Characteristics ◽

Internal Structures

Excavation at a crop-mark site found close to Annan, Dumfries and Galloway, revealed evidence of a ring-ditch containing a number of intriguing internal structures. Initially this was presumed to be a prehistoric monument, but pottery and radiocarbon dating, unexpectedly, indicated that the main structural phase of the site falls between the 11th-13th centuries AD. This suggests that a degree of caution is required when interpreting crop-mark sites on morphological characteristics alone. Moreover this excavation makes clear that morphological interpretation can have a constraining influence on excavation strategy, so caution is required when designing fieldwork programmes.

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