scholarly journals Laophontodes typicus T. Scott (Copepoda, Harpacticoida, Laophontodinae) – discovering a species complex by morphology

Author(s):  
Kai Horst George

It appeared necessary to undertake a redescription of Laophontodes typicus T. Scott, 1894, but with the absence of the type specimen, several additional individuals collected from a number of regions were studied. The specimens chosen were from the western coast of Sussex and the Scottish Firth of Forth (UK), the Skjerstad fjord (Norway), the Patagonian continental slope (Chile) and the Great Meteor Seamount (subtropical north-eastern Atlantic Ocean). All specimens examined had been previously determined as L. typicus and deposited in the collections of renowned research institutions. However, detailed morphological comparison revealed that only the Sussex material can be assigned to L. typicus; the remaining specimens represent distinct species whose original assignment to L. typicus was erroneous, due to a morphological ambiguity. Thus, the current status of L. typicus must be regarded as a species complex. The Sussex material enabled a detailed redescription of L. typicus. Additionally, five new species are described, namely L. scottorum sp. nov., L. sarsi sp. nov., L. gertraudae sp. nov., L. monsmaris sp. nov. and L. norvegicus sp. nov. They exhibit some morphological similarity, but equally present discrete characters justifying their establishment as distinct taxa. The descriptions are accompanied by a detailed discussion that explains the justification of the splitting of L. typicus.

2021 ◽  
Vol 12 ◽  
Author(s):  
Xingxing Mao ◽  
Ji Wang ◽  
Nawal Shrestha ◽  
Yazhen Ma ◽  
Jianquan Liu

Delimitating species boundaries is the primary aim of biological classification and could be critical for evaluating the evolving process of species and conserving biodiversity. Rhododendron is an iconic group with an extraordinary diversity in southwest China. However, it remains unknown whether the recorded species therein comprise independently evolving lineages or artificially delimitated morphological entities. In this study, we carried out species delimitation of four Rhododendron species in the R. vernicosum-R. decorum species complex based on morphological analyses and population genetic data from nuclear simple sequence repeats (SSR) markers. We randomly selected a total of 105 specimens of different individuals identified as four species across their distributional ranges to examine the statistically distinct phenotypic clusters based on 19 morphological traits. Similarly, we genotyped 55 individuals of four species from 21 populations using 15 SSR markers. The morphological analyses sorted R. decorum and the other three species into two different phenotypic clusters. The genetic clusters were consistent with the morphological clusters. However, we also recovered the third genetic cluster, comprising six R. vernicosum populations and containing the admixed genetic compositions of the other two distinct genetic clusters. This hybrid group was morphologically similar to the typical R. vernicosum (including the samples from its type specimen locality and both R. verruciferum and R. gonggashanense) but with more genetic ancestry from R. decorum. Based on our findings, we identify two distinct species and one putative hybrid group due to introgression in the R. vernicosum-R. decorum species complex. We propose to merge R. verruciferum and R. gonggashanense into R. vernicosum based on genetic compositions and our morphological analyses. The hybrid group inferred from our findings, however, needs further investigations.


2020 ◽  
Vol 324 (2) ◽  
pp. 262-272
Author(s):  
I.V. Doronin ◽  
T.N. Dujsebayeva ◽  
K.M. Akhmedenov ◽  
A.G. Bakiev ◽  
K.N. Plakhov

The article specifies the type locality of the Steppe Ribbon Racer. The holotype Coluber (Taphrometopon) lineolatus Brandt, 1838 is stored in the reptile collection of the Zoological Institute of the Russian Academy of Sciences (ZISP No 2042). Literature sources provide different information about the type locality. A mistake has been made in the title of the work with the original species description: the western coast of the sea was indicated instead of the eastern one. The place of capture was indicated as “M. Caspium” (Caspian Sea) on the label and in the reptile inventory book of the Zoological Museum of the Academy of Sciences. The specimen was sent to the museum by G.S. Karelin. The “1842” indicated on the labels and in the inventory book cannot be the year of capture of the type specimen, just as the “1837” indicated by A.M. Nikolsky. In 1837, Karelin was in Saint Petersburg and in 1842 in Siberia. Most likely, 1837 is the year when the collection arrived at the Museum, and 1842 is the year when the information about the specimen was recorded in the inventory book (catalog) of the Zoological Museum of the Academy of Sciences. In our opinion, the holotype was caught in 1932. From Karelin’s travel notes of the expedition to the Caspian Sea in 1832, follows that the snake was recorded in two regions adjacent to the eastern coast of the Caspian Sea – Ungoza Mountain (“Mangyshlak Mountains”) and site of the Western Chink of Ustyurt between Zhamanairakty and Kyzyltas Mountains (inclusive) on the northeast coast of Kaydak Sor (“Misty Mountains”). In our article, Karelin’s route to the northeastern coast of the Caspian Sea in 1832 and photographs of these localities are given. The type locality of Psammophis lineolatus (Brandt, 1838) should be restricted to the Mangystau Region of the Kazakhstan: Ungoza Mountain south of Sarytash Gulf, Mangystau (Mangyshlak) Penninsula (44°26´ N, 51°12´ E).


Author(s):  
Anna Lavecchia ◽  
Matteo Chiara ◽  
Caterina De Virgilio ◽  
Caterina Manzari ◽  
Carlo Pazzani ◽  
...  

Abstract Staphylococcus cohnii (SC), a coagulase-negative bacterium, was first isolated in 1975 from human skin. Early phenotypic analyses led to the delineation of two subspecies (subsp.), Staphylococcus cohnii subsp. cohnii (SCC) and Staphylococcus cohnii subsp. urealyticus (SCU). SCC was considered to be specific to humans whereas SCU apparently demonstrated a wider host range, from lower primates to humans. The type strains ATCC 29974 and ATCC 49330 have been designated for SCC and SCU, respectively. Comparative analysis of 66 complete genome sequences—including a novel SC isolate—revealed unexpected patterns within the SC complex, both in terms of genomic sequence identity and gene content, highlighting the presence of 3 phylogenetically distinct groups. Based on our observations, and on the current guidelines for taxonomic classification for bacterial species, we propose a revision of the SC species complex. We suggest that SCC and SCU should be regarded as two distinct species: SC and SU (Staphylococcus urealyticus), and that two distinct subspecies, SCC and SCB (SC subsp. barensis, represented by the novel strain isolated in Bari) should be recognized within SC. Furthermore, since large scale comparative genomics studies recurrently suggest inconsistencies or conflicts in taxonomic assignments of bacterial species, we believe that the approach proposed here might be considered for more general application.


2021 ◽  
Vol 95 ◽  
Author(s):  
B. Sayyaf Dezfuli ◽  
E. Simoni ◽  
G. Bosi ◽  
M. Palomba ◽  
S. Mattiucci ◽  
...  

Abstract A survey on Anisakis simplex (sensu stricto (s.s.)) from blue whiting, Micromesistius poutassou, in the north-eastern Atlantic Ocean revealed the occurrence of high infection levels of third larval stages in visceral organs and flesh. Larvae were genetically identified with a multilocus approach as A. simplex (s.s.). Histochemical, immunohistochemical and ultrastructural observations were conducted on 30 M. poutassou specimens. Gonads, pyloric caeca and flesh harboured encapsulated larvae of A. simplex (s.s.) but no intense host reaction was encountered around the parasite in the above organs. In the liver, the most infected organ, the larvae co-occurred with the coccidian Goussia sp. Within the granuloma around the A. simplex (s.s.) larvae, two concentric layers were recognized, an inner mostly comprising electron-dense epithelioid cells and an outer layer made of less electron-dense epithelioid cells. Macrophages and macrophage aggregates (MAs) were abundant out of the granulomas, scattered in parenchyma, and inside the MAs, the presence of engulfed Goussia sp. was frequent. In liver tissue co-infected with Goussia sp. and A. simplex (s.s.), hepatocytes showed cytoplasmic rarefaction and acute cell swelling. Results suggest that the host-induced encapsulation of A. simplex (s.s.) larvae is a strategic compromise to minimize collateral tissue damage around the larval infection sites, to facilitate the survival of both parasite and host.


Nature ◽  
1971 ◽  
Vol 232 (5306) ◽  
pp. 112-112 ◽  
Author(s):  
T. M. LEATHERLAND ◽  
J. D. BURTON ◽  
M. J. MCCARTNEY ◽  
F. CULKIN

2015 ◽  
Vol 775 ◽  
pp. 415-435 ◽  
Author(s):  
Andrea A. Cimatoribus ◽  
H. van Haren

We present a detailed analysis of temperature statistics in an oceanographic observational dataset. The data are collected using a moored array of thermistors,$100~\text{m}$tall and starting$5~\text{m}$above the bottom, deployed during four months above the slopes of a Seamount in the north-eastern Atlantic Ocean. Turbulence at this location is strongly affected by the semidiurnal tidal wave. Mean stratification is stable in the entire dataset. We compute structure functions, of order up to 10, of the distributions of temperature increments. Strong intermittency is observed, in particular, during the downslope phase of the tide, and farther from the solid bottom. In the lower half of the mooring during the upslope phase, the temperature statistics are consistent with those of a passive scalar. In the upper half of the mooring, the temperature statistics deviate from those of a passive scalar, and evidence of turbulent convective activity is found. The downslope phase is generally thought to be more shear-dominated, but our results suggest on the other hand that convective activity is present. High-order moments also show that the turbulence scaling behaviour breaks at a well-defined scale (of the order of the buoyancy length scale), which is however dependent on the flow state (tidal phase, height above the bottom). At larger scales, wave motions are dominant. We suggest that our results could provide an important reference for laboratory and numerical studies of mixing in geophysical flows.


Phytotaxa ◽  
2016 ◽  
Vol 266 (1) ◽  
pp. 27 ◽  
Author(s):  
ANTHONY R. MAGEE ◽  
ODETTE E. CURTIS ◽  
B-E. VAN WYK

Extensive field surveys of the Critically Endangered Central and Eastern Rûens Shale Renosterveld have uncovered that Notobubon striatum, as currently circumscribed, comprises two distinct species. Upon careful examination of the type material it has become clear that names exist for both species. The type specimen of N. striatum clearly matches the lesser known species, a large shrub, ca. 1 m. tall, with a powerful anise-scent and which is restricted to the banks of seasonal rivers and watercourses in the Central and Eastern Rûens Shale Renosterveld. The second and better known entity, with a wider distribution, corresponds to the type material of Dregea collina Ecklon & Zeyher. As such, a new combination, Notobubon collinum (Ecklon & Zeyher) Magee, is here made to accommodate this taxon, restricted to dry quartz and silcrete patches or outcrops in Eastern Rûens Shale Renosterveld. In their revised circumscriptions N. striatum and N. collinum are readily distinguished by habit, scent, leaf size and division, as well as leaf lobe shape and sepal size. Comprehensive descriptions of both species are provided, together with notes on their ecology and conservation status, and the existing key to the species of Notobubon updated. This brings the number of recognised species in the genus to thirteen.


Author(s):  
Sarah C. Swan ◽  
John D.M. Gordon ◽  
Beatriz Morales-Nin ◽  
Tracy Shimmield ◽  
Terrie Sawyer ◽  
...  

Otoliths were obtained from Nezumia aequalis, a small macrourid that is widely distributed throughout the Atlantic and Mediterranean—two very different physical environments. Microchemical analysis of the otoliths was carried out using solution-based inductively coupled plasma mass spectrometry of whole otoliths. Significant differences between fish populations were found for concentrations of the elements Li and Sr. Only 54% of the samples were correctly classified by area using discriminant analysis. Otolith samples from the Reykjanes Ridge were most easily distinguished. The results are discussed in relation to trace element concentrations in the waters of the north-eastern Atlantic Ocean and the Mediterranean Sea.


2018 ◽  
Vol 43 ◽  
pp. 111-116
Author(s):  
Mustapha Hassoun ◽  
Hanaa Moussa ◽  
Ghizlane Salhi ◽  
Hanaa Zbakh ◽  
Hassane Riadi ◽  
...  

AbstractWe report new records and corological data for three Moroccan marine macroalgae that complete their distribution information. Radicilingua thysanorhizans is new record for Morocco; Champia compressa is recorded for the first time from the eastern coast of the Atlantic Ocean. Diplothamnion jolyi is widely distributed in the western coast of the Atlantic coast and Pacific Islands, and recently reported from the Mediterranean Sea; this new record from Moroccan Atlantic coast extends their distribution range.Key words: Algae, Atlantic Ocean, Champia compressa, Diplothamnion jolyi, Radicilingua thysanorhizans.ResumenSe aportan nuevos registros y datos corológicos para tres macroalgas marinas de Marruecos, que completan la información sobre su distribución. Radicilingua thysanorhizans es cita nueva para Marruecos. Champia compressa se registra por la primera vez en la costa oriental del Océano Atlántico. Diplothamnion jolyi se distribuye ampliamente en la costa occidental de la costa atlántica y las islas del Pacífico y ha sido recientemente citada en el mar Mediterráneo; esta nueva cita para costa Atlántica Marroquí amplia su rango de distribución.Palabras clave: Algae, Océano Atlántico, Champia compressa, Diplothamnion jolyi, Radicilingua thysanorhizans.


2017 ◽  
Vol 112 (3) ◽  
pp. 161-174 ◽  
Author(s):  
Nataly A Souza ◽  
Reginaldo P Brazil ◽  
Alejandra S Araki

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