scholarly journals Joermungandr bolti , an exceptionally preserved ‘microsaur’ from the Mazon Creek Lagerstätte reveals patterns of integumentary evolution in Recumbirostra

2021 ◽  
Vol 8 (7) ◽  
pp. 210319
Author(s):  
Arjan Mann ◽  
Ami S. Calthorpe ◽  
Hillary C. Maddin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
New Taxon ◽  
Phylogenetic Methods ◽  
Mazon Creek ◽  
Single Part ◽  
Scanning Electron

The Carboniferous Pennsylvanian-aged (309–307 Ma) Mazon Creek Lagerstätte produces some of the earliest fossils of major Palaeozoic tetrapod lineages. Recently, several new tetrapod specimens collected from Mazon Creek have come to light, including the earliest fossorially adapted recumbirostrans. Here, we describe a new long-bodied recumbirostran, Joermungandr bolti gen. et sp. nov., known from a single part and counterpart concretion bearing a virtually complete skeleton. Uniquely, Joermungandr preserves a full suite of dorsal, flank and ventral dermal scales, together with a series of thinned and reduced gastralia. Investigation of these scales using scanning electron microscopy reveals ultrastructural ridge and pit morphologies, revealing complexities comparable to the scale ultrastructure of extant snakes and fossorial reptiles, which have scales modified for body-based propulsion and shedding substrate. Our new taxon also represents an important early record of an elongate recumbirostran bauplan, wherein several features linked to fossoriality, including a characteristic recumbent snout, are present. We used parsimony phylogenetic methods to conduct phylogenetic analysis using the most recent recumbirostran-focused matrix. The analysis recovers Joermungandr within Recumbirostra with likely affinities to the sister clades Molgophidae and Brachystelechidae. Finally, we review integumentary patterns in Recumbirostra, noting reductions and losses of gastralia and osteoderms associated with body elongation and, thus, probably also associated with increased fossoriality.

New perspectives on Nephridiacanthus major (Acanthocephala: Oligacanthorhynchidae) collected from hedgehogs in Iran

2020 ◽  
Vol 94 ◽  
Author(s):  
O.M. Amin ◽  
M. Sharifdini ◽  
R.A. Heckmann ◽  
M. Zarean
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
Chemical Analysis ◽  
Central Asia ◽  
Molecular Profile ◽  
X Ray ◽  
The Family ◽  
First Time ◽  
Scanning Electron

We describe morphological features not previously reported for this old acanthocephalan Nephridiacanthus major (Bremser, 1811 in Westrumb, 1821) Golvan, 1962 first described over 200 years ago. Our specimens were collected from long-eared hedgehog Hemiechinus auritus (Gmelin, 1770) (Erinaceidae) in Iran. We compare the morphometrics of our material with others previously reported from the same host in Iran, Russia, central Asia and Europe. Our specimens had markedly smaller proboscides, proboscis hooks and lemnisci than those reported from Russia and central Asia, but comparable measurements of other structures with specimens previously described from other collections. We document our new observations with scanning electron microscopy features not previously demonstrable by other observers and provide a chemical analysis of proboscis hooks using energy-dispersive X-ray analysis for the first time. The molecular profile of this acanthocephalan, based on 18S rDNA and cox1 genes, was generated for the first time. The phylogenetic analysis showed that N. major is placed in a clade of the family Oligacanthorhynchidae, well separated from the families Moniliformidae and Gigantorhynchidae.

Fragilaria irregularis sp. nov. a new araphid species (Fragilariaceae, Bacillariophyta) from the River Adegoy, Krasnodar Territory, Russia

Phytotaxa ◽  
2021 ◽  
Vol 508 (2) ◽  
Author(s):  
DMITRY CHUDAEV ◽  
INGRID JÜTTNER ◽  
BART VAN DE VIJVER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
Similar Species ◽  
New Taxon ◽  
Weakly Convex ◽  
Diatom Flora ◽  
A New Species ◽  
Scanning Electron

During a survey of the diatom flora of the Adegoy River (Krasnodar Territory, Russia), an unknown Fragilaria species (Bacillariophyta) was found that could not be identified using the currently available literature and here we describe it as a new species. The morphology of Fragilaria irregularis sp. nov. was studied using light and scanning electron microscopy and compared to similar species including Fragilaria deformis, F. rinoi, F. septentrionalis and Fragilariforma bicapitata. It differed from these taxa in several characters. Most observed valves showed an irregular striation pattern, a feature not observed in other species. Other important differences include valve outline (linear with parallel margins) and stria density (7–14 in 10 µm, lower compared to all other species). The new taxon has a linear valve outline with parallel to weakly convex margins, subcapitate apices and a very irregular, coarse striation pattern.

scholarly journals Balantidium grimi n. sp. (Ciliophora, Litostomatea), a new species inhabiting the rectum of the frog Quasipaa spinosa from Lishui, China

Parasite ◽  
2018 ◽  
Vol 25 ◽  
pp. 29 ◽  
Author(s):  
Weishan Zhao ◽  
Can Li ◽  
Dong Zhang ◽  
Runqiu Wang ◽  
Yingzhen Zheng ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
New Species ◽  
Body Shape ◽  
Ssu Rdna ◽  
The Body ◽  
Molecular Phylogenetic ◽  
A New Species ◽  
Scanning Electron

Balantidium grimi n. sp. is described from the rectum of the frog Quasipaa spinosa (Amphibia, Dicroglossidae) from Lishui, Zhejiang Province, China. The new species is described by both light microscopy (LM) and scanning electron microscopy (SEM), and a molecular phylogenetic analysis is also presented. This species has unique morphological features in that the body shape is somewhat flattened and the vestibulum is “V”-shaped, occupying nearly 3/8 to 4/7 of the body length. Only one contractile vacuole, situated at the posterior body, was observed. The phylogenetic analysis based on SSU-rDNA indicates that B. grimi groups together with B. duodeni and B. entozoon. In addition, the genus Balantidium is clearly polyphyletic.

Cocconeis kurakakea, a new diatom species from Nukutavake (Tuamotu Archipelago, South Pacific): description and comparison with C. diruptoides and C. pseudodiruptoides

Phytotaxa ◽  
2018 ◽  
Vol 349 (2) ◽  
pp. 115 ◽  
Author(s):  
CATHERINE RIAUX-GOBIN ◽  
ANDRZEJ WITKOWSKI ◽  
RICHARD W. JORDAN ◽  
VALERIANO PARRAVICINI ◽  
SERGE PLANES
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
South Pacific ◽  
Benthic Diatom ◽  
New Taxon ◽  
Diatom Species ◽  
The South ◽  
Standard Methods ◽  
Tuamotu Archipelago ◽  
Scanning Electron

During the ‘Tara Pacific 2016–2018 Expedition’, marine benthic diatom samples were collected from several Tuamotu atolls in the South Pacific. Preparation and examination of these samples were conducted following standard methods including light and scanning electron microscopy. A small-celled taxon from the genus Cocconeis Ehrenb. (Bacillariophyceae) is described from the Nukutavake reef, and compared to several other taxa for which the definition is not always clear (e.g., Cocconeis diruptoides Hust. and Cocconeis pseudodiruptoides Foged). The new taxon is present only on one of the investigated Tuamotu atolls, possibly indicating local endemism.

Staurosirella andino-patagonica sp. nov. (Bacillariophyta) from lake sediments in Patagonia, Argentina

Phytotaxa ◽  
2019 ◽  
Vol 402 (3) ◽  
pp. 131 ◽  
Author(s):  
JOSÉ MARÍA GUERRERO ◽  
MARÍA LUJÁN GARCÍA ◽  
EDUARDO A. MORALES
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Lake Sediments ◽  
Surface Sediments ◽  
Geographic Area ◽  
New Taxon ◽  
Diatom Flora ◽  
The Andes ◽  
Distinct Morphology ◽  
Scanning Electron

Staurosirella andino-patagonica, a new araphid diatom found in Holocene and recent surface sediments from lakes located in the Andes and adjacent steppe of Patagonia (Argentina), is described on the basis of light and scanning electron microscopy observations and comparison with related taxa. Although the elliptic valve outline of the new taxon resembles the smaller specimens of several Staurosirella species, ultrastructural features such as the presence of two spines on each virga and their distinct morphology -serrated with thickenings at the base- make Staurosirella andino-patagonica unique within the genus. Our study contributes to the knowledge of the Patagonian araphid diatom flora, a rather unexplored geographic area, and so we assume that, as additional areas are studied in detail, they will likely continue to yield new taxa.

Luticola puchalskiana, a new small terrestrial Luticola species (Bacillariophyceae) from the Maritime Antarctic Region

Phytotaxa ◽  
2020 ◽  
Vol 450 (1) ◽  
pp. 85-94
Author(s):  
NATALIA KOCHMAN-KĘDZIORA ◽  
RALITSA ZIDAROVA ◽  
TERESA NOGA ◽  
MARIA OLECH ◽  
BART VAN DE VIJVER
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Morphological Analysis ◽  
New Taxon ◽  
Maritime Antarctic ◽  
Antarctic Region ◽  
Diatom Flora ◽  
Terrestrial Habitats ◽  
Two Populations ◽  
Scanning Electron

During a survey of the terrestrial diatom flora of the Maritime Antarctic Region, an unknown Luticola taxon that could not be identified using the currently available literature was observed on two islands of the South Shetland Archipelago. After a detailed morphological analysis and comparison, the unknown taxon is described as Luticola puchalskiana sp. nov. The new species can be separated from other Luticola species based on its valve dimensions, stria density and the shape of both central and terminal raphe endings. Two populations of the new taxon were observed in samples collected from terrestrial habitats. The morphology of Luticola puchalskiana is elaborately described and illustrated using both light and scanning electron microscopy observations. A comparison is made with a large number of other morphologically similar Luticola species from the entire (sub)Antarctic Region.

Achnanthidium petuniabuktianum sp. nov. (Achnanthidiaceae, Bacillariophyta), a new representative of the A. pyrenaicum group from Spitsbergen (Svalbard Archipelago, High Arctic)

Phytotaxa ◽  
2015 ◽  
Vol 226 (1) ◽  
pp. 63 ◽  
Author(s):  
Eveline Pinseel ◽  
Bart Van de Vijver ◽  
Katerina Kopalova
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Arctic Region ◽  
High Arctic ◽  
New Taxon ◽  
Freshwater Lakes ◽  
Svalbard Archipelago ◽  
Diatom Flora ◽  
Littoral Zones ◽  
Scanning Electron

During a survey of the freshwater littoral diatom flora from lakes and ponds in the region of Petuniabukta on Spitsbergen (Svalbard Archipelago, High Arctic region), a new Achnanthidium species, A. petuniabuktianum sp. nov., has been recorded. Achnanthidium petuniabuktianum is a new representative of the A. pyrenaicum group as evidenced by its curved distal raphe fissures. The present paper describes in detail the morphology of A. petuniabuktianum based on light and scanning electron microscopy. The new taxon is characterized in having linear valves with parallel margins and broadly rounded, never protracted apices and a characteristic—in light microscopy hardly discernible—striation pattern consisting of very short striae composed of one or two small, always slit-like areolae. Based on current results, Achnanthidium petuniabuktianum is a benthic taxon occurring in epilithic and epiphytic habitats in the littoral zones of freshwater lakes and ponds.

Description of larva of Amblyomma romitii (Acari: Ixodidae) by optical and scanning electron microscopy, including porotaxy and phylogenetic analysis

2012 ◽  
Vol 60 (2) ◽  
pp. 271-280 ◽  
Author(s):  
Darci M. Barros-Battesti ◽  
Diego G. Ramirez ◽  
Janio dos Santos Sampaio ◽  
Katia M. Famadas ◽  
João Luiz H. Faccini ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
Scanning Electron

scholarly journals Comparative anatomy and phylogeny of the Forcipulatacea (Echinodermata: Asteroidea): insights from ossicle morphology

2019 ◽  
Vol 189 (3) ◽  
pp. 921-952 ◽  
Author(s):  
Marine Fau ◽  
Loïc Villier
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
Comparative Anatomy ◽  
Morphological Diversity ◽  
Consensus Tree ◽  
Sea Stars ◽  
Extant Species ◽  
Tree Resolution ◽  
Scanning Electron

Abstract A new phylogenetic analysis of the superorder Forcipulatacea is presented. Forcipulatacea is one of the three major groups of sea stars (Asteroidea: Echinodermata), composed of 400 extant species. The sampled taxa are thought to represent the morphological diversity of the group. Twenty-nine forcipulate taxa were sampled belonging to Asteriidae, Stichasteridae, Heliasteridae, Pedicellasteridae, Zoroasteridae and Brisingida. Specimens were dissected with bleach. Detailed description of the skeleton and the anatomy of the ossicles were investigated using scanning electron microscopy. Comparative anatomy allowed the scoring of 115 phylogenetically informative characters. The consensus tree resulting from the analysis recovers Asteriidae, Stichasteridae, Zoroasteridae and Brisingida as monophyletic. All types of morphological features contribute to tree resolution and may be appropriate for taxon diagnosis. The synapomorphies supporting different clades are described and discussed. Brisingida and Zoroasteridae are the best-supported clades. The potentially challenging position of Brisingida in the tree may be explained by homoplastic changes, but also by the presence of numerous non-applicable characters.

scholarly journals Nutlet Micromorphology and Character Evolution of Some Species of Rochelieae (Boraginaceae) and Its Systematic Implications

2021 ◽  
Author(s):  
Mostafa Ebadi ◽  
Sedigheh Nikzat
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
Sequence Data ◽  
Character Evolution ◽  
Species Level ◽  
Phylogenetic Significance ◽  
Dna Sequence Data ◽  
Micro Morphology ◽  
Scanning Electron

Abstract Background: The macro/micro-morphology of nutlets in 11 species (and 22 accessions) of the Boraginaceae family was investigated by stereomicroscope and scanning electron microscopy to evaluate the taxonomic relevance of these traits. To evaluate the phylogenetic significance of the character evolution, available DNA sequence data from GenBank were combined with selected original nutlet data, and phylogenetic analysis was performed.Results: The Rochelieae nutlets' shape varied from ovoid (ovoid, ovoid-triangular, and ovoid-rectangular) to the pyramid. Six major patterns were recognized based on nutlet ultrastructure characters. Rocheliae is characterized by a transition from “without appendage” to “with tubercles and prickles” on the nutlet disk, and also by a shift from “lack of prickles” to “glossy prickles”.Conclusions: The results indicated that the nutlet ultrastructure pattern of Rochelieae is systematically informative at the genus level, but not at the species level. The results showed that glochid is not an ancestral trait but is a synapomorphy and the transition to this trait occurred in the genus Lappula. The Close boundary of nutlet microstructures between L. barbata and L. microcarpa was discussed.

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