scholarly journals The early Cambrian fossil embryo Pseudooides is a direct-developing cnidarian, not an early ecdysozoan

2017 ◽  
Vol 284 (1869) ◽  
pp. 20172188 ◽  
Author(s):  
Baichuan Duan ◽  
Xi-Ping Dong ◽  
Luis Porras ◽  
Kelly Vargas ◽  
John A. Cunningham ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Developmental Stages ◽  
Radial Symmetry ◽  
Body Plan ◽  
Direct Development ◽  
Early Cambrian ◽  
Germ Band ◽  
Stages Of Development ◽  
Bayesian Phylogenetic Analysis ◽  
Indirect Development

Early Cambrian Pseudooides prima has been described from embryonic and post-embryonic stages of development, exhibiting long germ-band development. There has been some debate about the pattern of segmentation, but this interpretation, as among the earliest records of ecdysozoans, has been generally accepted. Here, we show that the ‘germ band’ of P. prima embryos separates along its mid axis during development, with the transverse furrows between the ‘somites’ unfolding into the polar aperture of the ten-sided theca of Hexaconularia sichuanensis , conventionally interpreted as a scyphozoan cnidarian; co-occurring post-embryonic remains of ecdysozoans are unrelated. We recognize H. sichuanensis as a junior synonym of P. prima as a consequence of identifying these two form-taxa as distinct developmental stages of the same organism. Direct development in P. prima parallels the co-occuring olivooids Olivooides, and Quadrapyrgites and Bayesian phylogenetic analysis of a novel phenotype dataset indicates that, despite differences in their tetra-, penta- and pseudo-hexa-radial symmetry, these hexangulaconulariids comprise a clade of scyphozoan medusozoans, with Arthrochites and conulariids, that all exhibit direct development from embryo to thecate polyp. The affinity of hexangulaconulariids and olivooids to extant scyphozoan medusozoans indicates that the prevalence of tetraradial symmetry and indirect development are a vestige of a broader spectrum of body-plan symmetries and developmental modes that was manifest in their early Phanerozoic counterparts.

scholarly journals Origins of radial symmetry identified in an echinoderm during adult development and the inferred axes of ancestral bilateral symmetry

2007 ◽  
Vol 274 (1617) ◽  
pp. 1511-1516 ◽  
Author(s):  
Valerie B Morris
Keyword(s):  
Sea Urchin ◽  
Adult Development ◽  
Bilateral Symmetry ◽  
Radial Symmetry ◽  
Body Plan ◽  
Direct Development ◽  
The Common ◽  
Patterning Genes ◽  
Standing Problem

How the radial body plan of echinoderms is related to the bilateral body plan of their deuterostome relatives, the hemichordates and the chordates, has been a long-standing problem. Now, using direct development in a sea urchin, I show that the first radially arranged structures, the five primary podia, form from a dorsal and a ventral hydrocoele at the oral end of the archenteron. There is a bilateral plane of symmetry through the podia, the mouth, the archenteron and the blastopore. This adult bilateral plane is thus homologous with the bilateral plane of bilateral metazoans and a relationship between the radial and bilateral body plans is identified. I conclude that echinoderms retain and use the bilateral patterning genes of the common deuterostome ancestor. Homologies with the early echinoderms of the Cambrian era and between the dorsal hydrocoele, the chordate notochord and the proboscis coelom of hemichordates become evident.

scholarly journals Onychophoran-like musculature in a phosphatized Cambrian lobopodian

2016 ◽  
Vol 12 (9) ◽  
pp. 20160492 ◽  
Author(s):  
Xi-Guang Zhang ◽  
Martin R. Smith ◽  
Jie Yang ◽  
Jin-Bo Hou
Keyword(s):  
Phylogenetic Analysis ◽  
Muscle Tissue ◽  
Three Dimensional ◽  
Body Plan ◽  
Early Cambrian ◽  
First Report ◽  
Rich Diversity ◽  
The Rich

The restricted, exclusively terrestrial distribution of modern Onychophora contrasts strikingly with the rich diversity of onychophoran-like fossils preserved in marine Cambrian Lagerstätten . The transition from these early forebears to the modern onychophoran body plan is poorly constrained, in part owing to the absence of fossils preserving details of the soft anatomy. Here, we report muscle tissue in a new early Cambrian (Stage 3) lobopodian, Tritonychus phanerosarkus gen. et sp. nov., preserved in the Orsten fashion by three-dimensional replication in phosphate. This first report of Palaeozoic onychophoran musculature establishes peripheral musculature as a characteristic of the ancestral panarthropod, but documents an unexpected muscular configuration. Phylogenetic analysis reconstructs T. phanerosarkus as one of a few members of the main onychophoran lineage—which was as rare and as cryptic in the Cambrian period as it is today.

scholarly journals Lassa Virus Circulation in Small Mammal Populations in Bo District, Sierra Leone

Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 28
Author(s):  
Umaru Bangura ◽  
Jacob Buanie ◽  
Joyce Lamin ◽  
Christopher Davis ◽  
Gédéon Ngiala Bongo ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Sierra Leone ◽  
Small Mammal ◽  
Hemorrhagic Fever ◽  
Lassa Fever ◽  
Lassa Virus ◽  
Sierra Leonean ◽  
Bayesian Phylogenetic Analysis ◽  
Prevalent Species ◽  
Lineage Iv

Lassa fever is a viral hemorrhagic fever caused by the Lassa virus LASV, which was first isolated in the rodent Mastomys natalensis in 1974 in Kenema, Sierra Leone. As little is known about the abundance and the presence of LASV in rodents living in the Bo area, we carried out a small mammal longitudinal population survey. A standardized trapping session was performed in various habitats and seasons in six villages over two years (2014–2016) and samples collected were tested for arenavirus IgG and LASV. A Bayesian phylogenetic analysis was performed on sequences identified by PCR. A total of 1490 small mammals were collected, and 16 rodent species were identified, with M. natalensis (355, 24%) found to be the most prevalent species. Forty-one (2.8%) samples were IgG positive, and 31 of these were trapped in homes and 10 in surrounding vegetation. Twenty-nine of 41 seropositive rodents were M. natalensis. We detected four LASV by PCR in two villages, all found in M. natalensis. Phylogenetic analysis showed that the sequences were distributed within the Sierra Leonean clade within lineage IV, distinguishing a Bo sub-clade older than a Kenema sub-clade. Compared to other settings, we found a low abundance of M. natalensis and a low circulation of LASV in rodents in villages around Bo district.

scholarly journals Case of Human Infestation with Dermanyssus gallinae (Poultry Red Mite) from Swallows (Hirundinidae)

Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 299
Author(s):  
Georgios Sioutas ◽  
Styliani Minoudi ◽  
Katerina Tiligada ◽  
Caterina Chliva ◽  
Alexandros Triantafyllidis ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Clinical Symptoms ◽  
Skin Lesions ◽  
Coi Gene ◽  
Dermanyssus Gallinae ◽  
Poultry Red Mite ◽  
Human Form ◽  
Bayesian Phylogenetic Analysis

Dermanyssus gallinae (the poultry red mite, PRM) is an important ectoparasite in the laying hen industry. PRM can also infest humans, causing gamasoidosis, which is manifested as skin lesions characterized by rash and itching. Recently, there has been an increase in the reported number of human infestation cases with D. gallinae, mostly associated with the proliferation of pigeons in cities where they build their nests. The human form of the disease has not been linked to swallows (Hirundinidae) before. In this report, we describe an incident of human gamasoidosis linked to a nest of swallows built on the window ledge of an apartment in the island of Kefalonia, Greece. Mites were identified as D. gallinae using morphological keys and amplifying the Cytochrome C oxidase subunit I (COI) gene by PCR. Bayesian phylogenetic analysis and median-joining network supported the identification of three PRM haplogroups and the haplotype isolated from swallows was identical to three PRM sequences isolated from hens in Portugal. The patient was treated with topical corticosteroids, while the house was sprayed with deltamethrin. After one week, the mites disappeared and clinical symptoms subsided. The current study is the first report of human gamasoidosis from PRM found in swallows’ nest.

New olenelline trilobites from the Northwest Territories, Canada, and the phylogenetic placement of Judomia absita Fritz, 1973

Zootaxa ◽  
2011 ◽  
Vol 2918 (1) ◽  
pp. 15 ◽  
Author(s):  
I. WESLEY GAPP ◽  
BRUCE S. LIEBERMAN ◽  
MICHAEL C. POPE ◽  
KELLY A. DILLIARD
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Northwest Territories ◽  
Phylogenetic Analyses ◽  
Geographic Range ◽  
Early Cambrian ◽  
Phylogenetic Placement ◽  
The Subject ◽  
Three New Species ◽  
One New Species

The Early Cambrian olenelline trilobites are a diverse clade and have been the subject of several phylogenetic analyses. Here, three new species of Bradyfallotaspis Fritz, 1972 (B. coriae, B. nicolascagei, and B. sekwiensis) and one new species of Nevadia Walcott, 1910 (N. saupeae) are described from the Sekwi Formation of the Mackenzie Mountains, Northwest Territories, Canada. In addition, new specimens potentially referable to Nevadia ovalis McMenamin, 1987 were recovered that may expand that species’ geographic range, which was thought to be restricted to Sonora, Mexico. The results of a phylogenetic analysis incorporating several olenelline taxa, including Judomia absita Fritz, 1973 from the Sekwi Formation, are also presented herein. This species has been assigned to various olenelline genera, including Judomia Lermontova, 1951 and Paranevadella Palmer & Repina, 1993. Phylogenetic analysis suggests this species is closely related to Judomia tera Lazarenko, 1960 from Siberia. This phylogenetic relationship provides further support for the hypothesis that a close biogeographic relationship existed between Laurentia and Siberia during the Cambrian.

Ultrastructural and molecular characterization of Bacillidium vesiculoformis n. sp. (Microspora: Mrazekiidae) in the freshwater oligochaete Nais simplex (Oligochaeta: Naididae)

Parasitology ◽  
2004 ◽  
Vol 130 (1) ◽  
pp. 31-40 ◽  
Author(s):  
D. J. MORRIS ◽  
R. S. TERRY ◽  
K. B. FERGUSON ◽  
J. E. SMITH ◽  
A. ADAMS
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Infected Cell ◽  
Host Cell ◽  
Developmental Stages ◽  
Parasite Development ◽  
Adhesive Quality ◽  
Transmission Studies ◽  
A New Species

The development of a new species, Bacillidium vesiculoformis n. sp. (Microspora, Mrazekiidae), is described from the freshwater oligochaete Nais simplex (Oligochaeta, Naididae). Initial stages of parasite development consist of a monokaryotic merogony within a haemocyte of the intestinal blood sinus. The resulting hypertrophied haemocyte is attached to the chloragocytes of the sinus by fine cytoplasmic extensions with the sinus around the cell becoming greatly enlarged. The meronts within the haemocyte form diplokaryotic sporonts that undergo sporogenesis directly within the cytoplasm of the host cell. The infected cell becomes packed with spores and developmental stages, causing it dramatically to increase in size, eventually rupturing the oligochaete and cell. Sporogony appears to be disporoblastic. Released spores were observed to have an adhesive quality. Transmission studies conducted with mature spores failed to transmit the parasite horizontally although vertical transmission was observed. Phylogenetic analysis of the parasite demonstrated that B. vesiculoformis clustered with microsporidian parasites of bryozoa and two other microsporidians, Janacekia debaiseuxi and an unidentified Bacillidium sp.

scholarly journals A biologist’s guide to Bayesian phylogenetic analysis

2017 ◽  
Vol 1 (10) ◽  
pp. 1446-1454 ◽  
Author(s):  
Fabrícia F. Nascimento ◽  
Mario dos Reis ◽  
Ziheng Yang
Keyword(s):  
Phylogenetic Analysis ◽  
Bayesian Phylogenetic Analysis

Phylogenetic analysis of some basal early Cambrian trilobites, the biogeographic origins of the Eutrilobita, and the timing of the Cambrian radiation

2002 ◽  
Vol 76 (4) ◽  
pp. 692-708 ◽  
Author(s):  
Bruce S. Lieberman
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Phylogenetic Analyses ◽  
Early Cambrian ◽  
Biogeographic Patterns ◽  
Two New Species ◽  
Vicariance Event ◽  
Cambrian Radiation ◽  
Early Radiation ◽  
Event Based

This paper presents a phylogenetic analysis of the “Fallotaspidoidea,” a determination of the biogeographic origins of the eutrilobites, and an evaluation of the timing of the Cambrian radiation based on biogeographic evidence. Phylogenetic analysis incorporated 29 exoskeletal characters and 16 ingroup taxa. In the single most parsimonious tree the genus Fallotaspidella Repina, 1961, is the sister taxon of the sutured members of the Redlichiina Richter, 1932. Phylogenetic analysis is also used to determine the evolutionary relationships of two new species of “fallotaspidoids” distributed in the White-Inyo Range of California that have been previously illustrated but not described. These species had been referred to Fallotaspis Hupé, 1953, and used to define the occurrence of the eponymous Fallotaspis Zone in southwestern Laurentia. However, these two new species need to be reassigned to Archaeaspis Repina in Khomentovskii and Repina, 1965. They are described as Archaeaspis nelsoni and A. macropleuron. Their phylogenetic status suggests that the Fallotaspis Zone in southwestern Laurentia is not exactly analogous to the Fallotaspis Zone in Morocco, where that division was originally defined. Thus, changes to the biostratigraphy of the Early Cambrian of southwestern Laurentia may be in order. Furthermore, specimens of a new species referable to Nevadia Walcott, 1910, are recognized in strata traditionally treated as within the Fallotaspis Zone, which is held to underlie the Nevadella Zone, suggesting further biostratigraphic complexity within the basal Lower Cambrian of southwestern Laurentia.Phylogenetic analyses of the Olenellina and Olenelloidea, along with the phylogenetic analysis presented here, are used to consider the biogeographic origins of the eutrilobites. The group appears to have originated in Siberia. Biogeographic patterns in trilobites, especially those relating to the split between the Olenellid and Redlichiid faunal provinces are important for determining the timing of the Cambrian radiation. Some authors have argued that there was a hidden radiation that significantly predated the Cambrian, whereas others have suggested that the radiation occurred right at the start of the Cambrian. The results from trilobite biogeography presented here support an early radiation. They are most compatible with the notion that there was a vicariance event relating to the origin of the redlichiinid trilobites, and thus the eponymous Redlichiid faunal province, from the “fallotaspidoids,” whose representatives were part of the Olenellid faunal province. This vicariance event, based on biogeographic patterns, is likely related to the breakup of Pannotia which occurred sometime between 600–550 Ma, suggesting that the initial episodes of trilobite cladogenesis occurred within that interval. As trilobites are relatively derived arthropods, this suggests that Númerous important episodes of metazoan cladogenesis precede both the earliest trilobitic part of the Early Cambrian, and indeed, even the Early Cambrian.

scholarly journals The Developmental Stages of An Accumulative Cone of Dry Valley as an Indication of Change in Natural Environment Conditions (Western Pomerania)

2013 ◽  
Vol 32 (1) ◽  
pp. 15-20 ◽  
Author(s):  
Renata Paluszkiewicz
Keyword(s):  
Natural Environment ◽  
Developmental Stages ◽  
Main Stage ◽  
Stages Of Development ◽  
Fluvial Transport ◽  
Dry Valley

Abstract The aim of this paper is to present the stages of development of an alluvial cone as an indication of change in natural environment conditions. a detailed research was conducted within the upland regions of Drawsko Lakeland. At the valley mouth of one of the erosional-denudational valleys an alluvial cone in question splays out. The imparity between the capacity of the erosional-denudational valley and the capacity of the alluvial cone indicates that the main stage of erosion had taken place before the cone’s deposition. During the beginning stage the material acquired from the dissection was most likely delivered directly to the channel of Dębnica river and was incorporated in the fluvial transport. The cone was formed during the later stage. The results of the radiocarbon analyses reveal that the formation of the alluvial cone and the valley associated with the cone took place during the Subatlantic. It was also estimated that the cone aggraded with the rate of approximately 3,9 mm per year

scholarly journals Genomic Analysis of the Glutathione S-Transferase Family in Pear (Pyrus communis) and Functional Identification of PcGST57 in Anthocyanin Accumulation

2022 ◽  
Vol 23 (2) ◽  
pp. 746
Author(s):  
Bo Li ◽  
Xiangzhan Zhang ◽  
Ruiwei Duan ◽  
Chunhong Han ◽  
Jian Yang ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Developmental Stages ◽  
Genomic Analysis ◽  
Pyrus Communis ◽  
Anthocyanin Content ◽  
Anthocyanin Accumulation ◽  
Rna Seq ◽  
Virus Induced Gene Silencing ◽  
Functional Identification ◽  
Glutathione S Transferase

Anthocyanin accumulation in vacuoles results in red coloration in pear peels. Glutathione S-transferase (GST) proteins have emerged as important regulators of anthocyanin accumulation. Here, a total of 57 PcGST genes were identified in the European pear ‘Bartlett’ (Pyrus communis) through comprehensive genomic analysis. Phylogenetic analysis showed that PcGST genes were divided into 10 subfamilies. The gene structure, chromosomal localization, collinearity relationship, cis-elements in the promoter region, and conserved motifs of PcGST genes were analyzed. Further research indicated that glutamic acid (Glu) can significantly improve anthocyanin accumulation in pear peels. RNA sequencing (RNA-seq) analysis showed that Glu induced the expression of most PcGST genes, among which PcGST57 was most significantly induced. Further phylogenetic analysis indicated that PcGST57 was closely related to GST genes identified in other species, which were involved in anthocyanin accumulation. Transcript analysis indicated that PcGST57 was expressed in various tissues, other than flesh, and associated with peel coloration at different developmental stages. Silencing of PcGST57 by virus-induced gene silencing (VIGS) inhibited the expression of PcGST57 and reduced the anthocyanin content in pear fruit. In contrast, overexpression of PcGST57 improved anthocyanin accumulation. Collectively, our results demonstrated that PcGST57 was involved in anthocyanin accumulation in pear and provided candidate genes for red pear breeding.

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