scholarly journals Integrative descriptions of two new Macrobiotus species (Tardigrada, Eutardigrada, Macrobiotidae) from Mississippi (USA) and Crete (Greece)

2021 ◽  
Vol 97 (1) ◽  
pp. 281-306
Author(s):  
Matteo Vecchi ◽  
Daniel Stec
Keyword(s):  
18S Rrna ◽  
Molecular Data ◽  
Integrative Taxonomy ◽  
Distal Portion ◽  
Morphological Data ◽  
28S Rrna ◽  
Morphometric Characters ◽  
Clade B ◽  
Specific Morphology ◽  
Definition Of

In this paper, we describe two new Macrobiotus species from Mississippi (USA) and Crete (Greece) by means of integrative taxonomy. Detailed morphological data from light and scanning electron microscopy, as well as molecular data (sequences of four genetic markers: 18S rRNA, 28S rRNA, ITS-2 and COI), are provided in support of the descriptions of the new species. Macrobiotus annewintersaesp. nov. from Mississippi belongs to the Macrobiotus persimilis complex (Macrobiotus clade B) and exhibits a unique egg processes morphology, similar only to Macrobiotus anemone Meyer, Domingue & Hinton, 2014, but mainly differs from that species by the presence of eyes, granulation on all legs, dentate lunulae on legs IV, and of bubble-like structures within the tentacular arms that are present on the distal portion of the egg processes. Macrobiotus rybakisp. nov. from Crete belongs to the Macrobiotus clade A and is most similar to Macrobiotus dariae Pilato & Bertolani, 2004, Macrobiotus noemiae Roszkowska & Kaczmarek, 2019, Macrobiotus santoroi Pilato & D’Urso, 1976, and Macrobiotus serratus Bertolani, Guidi & Rebecchi, 1996, but differs from them mainly in the morphological details of its egg processes and chorion reticulation, but also by a number of morphometric characters. In light of the specific morphology of the egg processes of Macrobiotus annewintersaesp. nov. and Macrobiotus anemone, that are equipped with tentacular arms instead of proper terminal disc, we also provide an updated definition of the Macrobiotus persimilis complex.

scholarly journals New Records of Dactylobiotus parthenogeneticus Bertolani, 1982 Provide Insight into Its Genetic Variability and Geographic Distribution

2020 ◽  
Vol 68 (2) ◽  
pp. 57-72 ◽  
Author(s):  
Justyna Pogwizd ◽  
Daniel Stec
Keyword(s):  
Dna Sequences ◽  
18S Rrna ◽  
Haplotype Diversity ◽  
Original Description ◽  
Integrative Taxonomy ◽  
Morphological Data ◽  
Morphological Identification ◽  
28S Rrna ◽  
Mitochondrial Coi ◽  
Insight Into

In sediment samples collected from three distinct European locations (United Kingdom, France, Poland), populations of Dactylobiotus parthenogeneticus were found. The original description of this species was based solely on the morphology observed with light microscopy and later supplemented by some additional SEM data of the buccal apparatus and DNA sequences of 18S rRNA and COI. Here we provide an updated description of the species by means of integrative taxonomy. The description comprises a comprehensive set of morphometric and morphological data from light and scanning microscopy as well as nucleotide sequences of three nuclear (18S rRNA, 28S rRNA, ITS-2) and one mitochondrial (COI) fragments. Our analysis of haplotype diversity confirmed our morphological identification and showed that D. parthenogeneticus is widely distributed in Europe.

Integrative description of Hypsibius repentinus sp. nov. (Eutardigrada: Hypsibiidae) from Sweden

2021 ◽  
Vol 30 (1) ◽  
pp. 101-115
Author(s):  
D.V. Tumanov ◽  
G.S. Avdeeva
Keyword(s):  
18S Rrna ◽  
Species Group ◽  
Integrative Approach ◽  
Similar Species ◽  
28S Rrna ◽  
Morphometric Characters ◽  
Morphological Diagnosis ◽  
A New Species ◽  
Scanning Electron ◽  
Hypsibius Dujardini

A new species of tardigrade from the genus Hypsibius Ehrenberg, 1848 is described from the bottom sediments of a small lake in the central part of Scandinavian Peninsula (Sweden), using an integrative approach, i.e. morphological techniques (light and scanning electron microscopy) combined with a molecular analysis (18S rRNA, 28S rRNA, ITS-2 and COI markers). Hypsibius repentinus sp. nov. belongs to the Hypsibius dujardini species–group and differs from the most similar species of this group in having a second macroplacoid with a definite constriction and in some other morphometric characters. Morphological diagnosis for the Hypsibius dujardini species–group is proposed, and its composition is discussed.

scholarly journals Taxonomical considerations and molecular phylogeny of the closely related genera Bitylenchus, Sauertylenchus and Tylenchorhynchus (Nematoda: Telotylenchinae), with one new and four known species from Iran

2020 ◽  
Vol 94 ◽  
Author(s):  
M. Hosseinvand ◽  
A. Eskandari ◽  
S. Ganjkhanloo ◽  
R. Ghaderi ◽  
P. Castillo ◽  
...  
Keyword(s):  
New Species ◽  
Anterior Part ◽  
Phylogenetic Analyses ◽  
Ribosomal Subunit ◽  
Molecular Data ◽  
28S Rrna ◽  
Natural Habitats ◽  
Morphometric Characters ◽  
Molecular Approaches ◽  
Tail Tip

Abstract During several nematological surveys in cultivated and natural habitats in Khuzestan and Zanjan provinces of Iran, a new species, Bitylenchus parvulus n. sp., two new records for Iran – namely, Tylenchorhynchus agri and Tylenchorhynchus graciliformis – and a population of Bitylenchus parvus and one of Sauertylenchus maximus were recovered and characterized based upon morphological and molecular approaches. The new species is characterized by lip region with five to seven annuli, stylet 17.7 (17.0–18.5) μm long, sub-cylindrical tail narrowing abruptly near terminus giving a bluntly digitate shape to the tail tip, cuticle near anterior part of vulva wrinkled and post-rectal sac occupies whole of tail cavity. The phylogenetic analyses were carried out using molecular data from D2–D3 expansion segments of large ribosomal subunit (28S rRNA) for all studied species and the partial small ribosomal subunit (18S rRNA) for the new species. The representatives of Bitylenchus and Sauertylenchus formed distinct clades from Tylenchorhynchus members, supporting the hypothesis in which Bitylenchus and Sauertylenchus could be considered as valid genera, but rejecting the ‘large-genus’ concept for Tylenchorhynchus. Also, Sauertylenchus ibericus was proposed as a junior synonym of S. maximus based on the results from morphological and phylogenetic analysis. Furthermore, an identification key for all known species included in the three genera Bitylenchus, Tylenchorhynchus and Sauertylenchus is presented herein. The number of transverse annuli on the lip region and presence/absence of post-rectal sac were considered as the main diagnostic characters for classifying the species into seven groups, and other morphological and morphometric characters were subsequently used for distinguishing species in each group.

scholarly journals Integrative Descriptions of Two New Tardigrade Species along with the New Record of Mesobiotus skorackii Kaczmarek et al., 2018 from Canada

Diversity ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 394
Author(s):  
Pushpalata Kayastha ◽  
Milena Roszkowska ◽  
Monika Mioduchowska ◽  
Magdalena Gawlak ◽  
Łukasz Kaczmarek
Keyword(s):  
Large Population ◽  
Original Description ◽  
Molecular Data ◽  
28S Rrna ◽  
Moss Sample ◽  
Morphometric Characters ◽  
Mitochondrial Coi ◽  
Canadian Population ◽  
Coi Sequences ◽  
Morphology And Morphometry

Two new tardigrade species from a moss sample collected in Canada, one representing Macrobiotus hufelandi complex and the second one belonging to the genus Bryodelphax, are described. Integrative analysis was undertaken based on morphological and morphometric data (using both light and scanning electron microscopy (SEM)) combined with multilocus molecular analysis (nuclear sequences, i.e., 18S rRNA, 28S rRNA and ITS-2 as well as mitochondrial COI barcode sequences). Based on COI sequences, Macrobiotus birendrai sp. nov. is most similar to Mac. canaricus (p-distance 17%), whereas Bryodelphax mareki sp. nov. is most similar to Bry. parvulus (p-distance 16%). Both species differ also from their congeners in some morphological and morphometric characters of adults and/or details of egg chorion. Additionally, a large population of Mesobiotus skorackii was found in the sample and this is the first report of this species outside its terra typica in Kirghizia. The original description of this species was prepared based solely on the morphology and morphometry, therefore, here we provide updated data for this species enclosing morphometric and molecular data for the Canadian population.

Determining the position of Diomocoris, Micromimetus and Taylorilygus in the Lygus-complex based on molecular data and first records of Diomocoris and Micromimetus from Australia, including four new species (Insecta : Hemiptera : Miridae : Mirinae)

2021 ◽  
Author(s):  
Anna A. Namyatova ◽  
Michael D. Schwartz ◽  
Gerasimos Cassis
Keyword(s):  
New Species ◽  
16S Rrna ◽  
Morphological Study ◽  
18S Rrna ◽  
Initial Step ◽  
Sister Group ◽  
Molecular Data ◽  
28S Rrna ◽  
Group Relationships ◽  
First Time

The Lygus-complex is one of the most taxonomically challenging groups of Miridae (Heteroptera), and its Australian fauna is poorly studied. Here we examine the Australian taxa of the Lygus-complex using morphological and molecular methods. After a detailed morphological study of the material collected throughout Australia, Taylorilygus nebulosus is transferred to Diomocoris, with the genus recorded for the first time in this country. Taylorilygus apicalis, also widely distributed in Australia, is redescribed on the basis of Australian material. The genus Micromimetus is recorded for the first time in Australia, with M. celiae, sp. nov., M. hannahae, sp. nov., M. nikolai, sp. nov. and M. shofneri, sp. nov. described as new to science. Micromimetus pictipes is redescribed and its distributional range is increased. The monophyly of the Lygus-complex and relationships within this group were tested using cytochrome c oxidase subunit I (COI), 16S rRNA, 18S rRNA and 28S rRNA markers. The Lygus-complex has been found to be non-monophyletic. Phylogeny confirmed the monophyly of Micromimetus, and it has shown that Taylorilygus apicalis is closer to Micromimetus species than to Diomocoris nebulosus. This study is the initial step in understanding the Lygus-complex phylogeny; analyses with more taxa, more genes and morphology are needed to reveal the interrelationships within this group, and sister-group relationships of Australian taxa. http://zoobank.org/urn:lsid:zoobank.org:pub:7393D96B-2BBA-438D-A134-D372EFE7FB9E

Studies on Longidorus iberis (Escuer & Arias, 1997) n. comb. (Nematoda: Longidoridae) from Spain

Nematology ◽  
2021 ◽  
pp. 1-15
Author(s):  
Ilenia Clavero-Camacho ◽  
Gracia Liébanas ◽  
Miguel Escuer ◽  
Carolina Cantalapiedra-Navarrete ◽  
Antonio Archidona-Yuste ◽  
...  
Keyword(s):  
Molecular Markers ◽  
18S Rrna ◽  
Molecular Data ◽  
Valid Species ◽  
28S Rrna ◽  
Closely Related Species ◽  
North West ◽  
Molecular Studies ◽  
First Time ◽  
Partial 18S

Summary Specimens of a thin longidorid species collected in Peñalba (Huesca), north-west Spain, were previously described as Paralongidorus iberis. However, we conclude, through scanning electron microscopy and molecular studies on a population from about 15 km from the type locality and on paratype specimens, that this species was originally placed in the wrong genus. Both populations have pore-like amphidial apertures, not slit-like as in Paralongidorus, and the species is therefore transferred to Longidorus. Longidorus iberis n. comb. is regarded as a valid species and is clearly different from closely related species such as L. tabernensis, L. iliturgiensis, L. alvegus and L. indalus in morphometrics and molecular markers. Molecular data are reported for the first time, including the D2-D3 expansion segments of 28S rRNA, ITS1 rRNA, partial 18S rRNA and partial mitochondrial coxI regions. These molecular markers were used for inferring the phylogenetic relationships with other species within Longidorus and Paralongidorus, all clearly separating L. iberis n. comb. from other related taxa and placing the species in the Longidorus clade, rather than with Paralongidorus.

scholarly journals Variation in male reproductive system characters in Corydoradinae (Loricarioidei: Callichthyidae) reflects the occurrence of different lineages in this subfamily

2017 ◽  
Vol 15 (1) ◽  
Author(s):  
Maria A. Spadella ◽  
Simone P. Desan ◽  
Teresa C. B. P. O. Henriques ◽  
Claudio Oliveira
Keyword(s):  
Reproductive System ◽  
Dna Content ◽  
Molecular Data ◽  
Male Reproductive System ◽  
Monophyletic Group ◽  
Morphological Data ◽  
Morphometric Data ◽  
Recent Proposal ◽  
Definition Of ◽  
Lineage Variation

ABSTRACT Callichthyidae comprises a well-corroborated monophyletic group divided into two subfamilies: Corydoradinae and Callichthyinae. A recent proposal, based on molecular data, suggests that Corydoradinae is composed by nine monophyletic lineages, possibly genera. The species pertaining to those lineages have extensive modification in the size of genome, including diploid, tetraploid and octoploid species. Considering the occurrence of these monophyletic lineages and that the variations in DNA content may imply in significant alterations on the structure of spermatozoa, this study analyzed the morphology of the male reproductive system and the morphometry of the head of the spermatozoa of representatives of the nine lineages of Corydoradinae, seeking for particular characteristics of each lineage. Morphological data revealed a high intra-lineage variation, larger than that observed among species of different lineages. In contrast, morphometric data obtained for eight out of the nine lineages, revealed large congruency with the hypothesis that Corydoradinae is composed by different lineages. These results demonstrate that there is a correlation among variations in DNA content and the size of the spermatozoon head, thus providing additional subsides for the definition of the Corydoradinae lineages.

scholarly journals Hidden diversity of the most basal tapeworms (Cestoda, Gyrocotylidea), the enigmatic parasites of holocephalans (Chimaeriformes)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel Barčák ◽  
Chia-Kwung Fan ◽  
Pasaikou Sonko ◽  
Roman Kuchta ◽  
Tomáš Scholz ◽  
...  
Keyword(s):  
Molecular Data ◽  
Morphological Data ◽  
28S Rrna ◽  
Genotype 3 ◽  
Genotype 4 ◽  
Genetic Lineages ◽  
The North ◽  
Living Fossils ◽  
Morphological And Molecular Data ◽  
Taxonomic Studies

AbstractGyrocotylideans are evolutionary ancient parasitic flatworms, and like their hosts—a relict group of holocephalan fishes (Chimaeriformes)—they are considered to be “living fossils” of a vanished past. However, the species diversity, host associations and biogeography of these most basal tapeworms are poorly known. Herein, we provide evidence of a conspicuous contrast between the genetic and morphological data based on an examination of newly collected and properly processed Gyrocotyle specimens (hologenophores) isolated from holocephalans off Taiwan and Argentina. Our molecular data, inferred from three genes (COI, 28S rRNA, 18S rRNA), showed unexpected genetic interrelationships among isolates of the genus Gyrocotyle, because each of the four genotypes from Taiwan clustered with isolates of distinct gyrocotylideans from the North Atlantic. Three genotypes of Gyrocotyle from Taiwan were morphologically almost indistinguishable from each other but represented distinct genetic lineages; a single specimen of Gyrocotyle sp. genotype 4 exhibited a clear genetic and morphological distinctness, though its formal description as a new species would be premature. Additionally, specimens of Gyrocotyle rugosa Diesing, 1850, from the type host Callorhinchus callorynchus from Argentina, provided the first genetic data on the type species of the genus and enabled us to characterise it, which is necessary for future taxonomic studies. The finding of some specimens of Gyrocotyle sp. genotype 3 in Chimaera phantasma, and another one in C. cf. argiloba, together with the putative conspecificity of an unidentified gyrocotylidean from Callorhinchus milii off Australia and G. rugosa from C. callorynchus off Argentina, represent evidence that one gyrocotylidean species may parasitise more than one holocephalan host species. Existing taxonomic problems and conflicts between morphological and molecular data on species of Gyrocotyle can only be resolved if hologenophores from type hosts and localities of nominal taxa are properly characterised genetically and morphologically.

scholarly journals Integrative description of a new Tunisian tardigrade species, Macrobiotus azzunae sp. nov. (Eutardigrada, Macrobiotidae, hufelandi group)

2021 ◽  
Vol 758 ◽  
Author(s):  
Jamila Ben Marnissi ◽  
Michele Cesari ◽  
Lorena Rebecchi ◽  
Roberto Bertolani
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
18S Rrna ◽  
Integrated Approach ◽  
Molecular Data ◽  
28S Rrna ◽  
Considerable Potential ◽  
Mitochondrial Coi ◽  
Taxonomic Approach ◽  
Scanning Electron

In this paper a new tardigrade species, Macrobiotus azzunae sp. nov., from Tunisia, is described. An integrative taxonomic approach was applied by combining morphological, morphometric and molecular data. In particular, light and scanning electron microscopy observations, and four genetic markers, three nuclear (18S rRNA, 28S rRNA and ITS-2) and one mitochondrial (COI) were used. The analysis showed that M. azzunae sp. nov. belongs to the Macrobiotus hufelandi group and is most similar to Macrobiotus sandrae Bertolani & Rebecchi, 1993. It differs from M. sandrae by a more pronounced constriction of the first macroplacoid (hardly visible in M. sandrae) and for the eggshell shape, with thinner wires of the reticulum and meshes around the processes larger than the inter-process meshes in M. azzunae sp. nov., while all meshes are similar in size in M. sandrae. The species is gonochoristic. With this discovery, there are 33 species of tardigrades identified in Tunisia, all non-marine. This result, compared with nearby Sicily, where more research has been conducted, indicates that there is a considerable potential for identification of new species. Further research will be most informative if multiple habitats are explored and if carried out with an integrated approach as done in this present work.

scholarly journals Integrative taxonomy identifies two new tardigrade species (Eutardigrada: Macrobiotidae) from Greenland

2020 ◽  
Author(s):  
Daniel Stec ◽  
Denis T. Tumanov ◽  
Reinhardt Møbjerg Kristensen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Integrative Taxonomy ◽  
Morphological Data ◽  
28S Rrna ◽  
Mitochondrial Coi ◽  
Morphometric Analyses ◽  
Taxonomic Methods ◽  
Two Populations ◽  
Scanning Electron

In this paper we describe Macrobiotus engbergi sp. nov. and Tenuibiotus zandrae sp. nov. from Greenland. Our study has involved both classical taxonomic methods, which include morphological and morphometric analyses conducted with the use of light and scanning electron microscopy, and genetic analysis based on four molecular markers (three nuclear: 18S rRNA, 28S rRNA, ITS-2, and one mitochondrial: COI). Moreover, we re-examined the type series of Tenuibiotus voronkovi (Tumanov, 2007) as well as the original sample where the species was found and we provide new morphological data from light and scanning electron microscopy which enabled us to amend its description. Finally, we also analysed slides with animals and egg of two populations from Nordaustlandet and Edgeøya (archipelago of Svalbard, Norway) designated as T. voronkovi within its recent redescription. The results and comparisons presented in our study question the validity of this designation. 

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