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John Patrick Kociolek - One of the best experts on this subject based on the ideXlab platform.
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Gomphonema Ehrenberg species from the Yuntai Mountains, Henan Province, China
Journal of Oceanology and Limnology, 2021Co-Authors: Qi Liu, Nini Cui, Jia Feng, Fangru Nan, Xudong Liu, Shulian Xie, John Patrick KociolekAbstract:We report on eight species of the freshwater diatom genus Gomphonema from aquatic habitats from the Yuntai Mountains of Henan Province, China. This work represents the first detailed descriptions of the freshwater diatoms from this centrally-located province in China. Of the eight taxa considered, five are new to science and another is given a “cf.” designation. Four of the eight species are similar in morphological features to other, “classical” species, with external areolar occlusions forming C-shaped openings. Another species is astigmate, and has distinct siliceous papillae located marginally on the exterior of the valves; this morphology has not been recognized previously for the genus. Two of the species have internal areolar and stigma occlusions. The diversity of morphological types of species in Gomphonema may relate to the ecosystems, with more diverse ecosystems harboring greater diversity of these morphological groups of Gomphonema.
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One new Gomphonema Ehrenberg (Bacillariophyta) from Guangxi Zhuang Autonomous Region, China
Phytotaxa, 2020Co-Authors: Fan Zhang, John Patrick Kociolek, Yan Liu, Maxim Kulikovskiy, Yawen FanAbstract:A new Gomphonema species is described from the Shiwan Mts. in Guangxi Zhuang Autonomous Region, Southwest China. This new species differs from other known members of the genus Gomphonema by its linear-lanceolate shape, wide axial area, slit-like areolae openings, one short spine at the headpole externally, and large pseudoseptum at each end internally. Morphological features of the new species are detailed with light and scanning electron microscopy. Comparisons with other similar species are made. This species appears to be closely related to other species of this genus possessing wide axial areas.
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A new freshwater Gomphonema Ehrenberg (Bacillariophyta) species from Eastern Himalayas, India
Fottea, 2020Co-Authors: Cheran Radhakrishnan, John Patrick Kociolek, Sudipta K. Das, Vikas Kumar, Balasubramanian KarthickAbstract:A new freshwater diatom species, Gomphonema adhikarii sp. nov., is described from a small road-side pool from the alpine region of Arunachal Pradesh, Eastern Himalayas, India. Detailed valve morphological features, based on both light and scanning electron microscopy, is presented and this taxon is compared with similar species. Gomphonema adhikarii has a distinct asymmetry about the apical axis and slightly bent foot pole area. The outline of the valve is slightly undulate, the valve centre is swollen and both apices are broadly rounded. This new species described from the Eastern Himalayas supports the idea of the area being rich in biodiversity, even with respect to the freshwater diatom flora.
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Valve ultrastructure of two species of the diatom genus Gomphonema Ehrenberg (Bacillariophyta) from Yunnan Province, China
Fottea, 2020Co-Authors: Yan Liu, John Patrick Kociolek, Yawen FanAbstract:We describe valve ultrastructure of two species of the freshwater diatom genus Gomphonema from a stream and Lugu Lake in Yunnan Province, China, and describe one of these two species as new to Science. Gomphonema emines Skuja was described over 80 years ago. This large, multistigmate species has uniseriate striae without occlusions, large pseudosepta and septa, and internal stigma openings that are round, positioned within ellipsoidal depressions on the extended central nodule. In these features it is distinguished from most of the 'typical' species of the genus. Gomphonema yunnaniana Y.Liu et Kociolek sp. nov. has biseriate striae without occlusions, a large, round external stigma opening and an internal stigma opening that is elevated and contained within a lip-like structure. In these features it is distinguished from the 'typical' species of the genus. We compare these two putatively endemic species from Yunnan with other species groups of the genus.
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Morphological investigation and description of two new Gomphonema Ehrenberg (Bacillariophyta) species from India and Vietnam with biogeographical comments
Issues of modern algology (Вопросы современной альгологии), 2019Co-Authors: Anton Glushchenko, John Patrick Kociolek, Maxim Kulikovskiy, Cheran Radhakrishnan, Samadhan Pardhi, Balasubramanian KarthickAbstract:Two new species of Gomphonema Ehrenberg are described on the basis of light and scanning electron microscopical observations. These are Gomphonema kallarensis sp. prov., a species found in India, and G. kezlyae sp. prov., which have been found in India and Vietnam. We also document the morphology and variability of G. doonensis B. Karthick, R. Nautiyal et Kociolek from Vietnam. This species was described originally from India based on a limited number of valves. Both G. doonensis and G. kallarensis have biseriate striae composed of areolae without occlusions, while G. kezlyae have striae with single row of areolae that have external occlusions giving the impression of C-shaped openings. Our investigation shows that India and Vietnam share some species in common, and adding additional evidence that the biogeography of freshwater diatoms from the Tropics warrants future investigation.
Yawen Fan - One of the best experts on this subject based on the ideXlab platform.
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One new Gomphonema Ehrenberg (Bacillariophyta) from Guangxi Zhuang Autonomous Region, China
Phytotaxa, 2020Co-Authors: Fan Zhang, John Patrick Kociolek, Yan Liu, Maxim Kulikovskiy, Yawen FanAbstract:A new Gomphonema species is described from the Shiwan Mts. in Guangxi Zhuang Autonomous Region, Southwest China. This new species differs from other known members of the genus Gomphonema by its linear-lanceolate shape, wide axial area, slit-like areolae openings, one short spine at the headpole externally, and large pseudoseptum at each end internally. Morphological features of the new species are detailed with light and scanning electron microscopy. Comparisons with other similar species are made. This species appears to be closely related to other species of this genus possessing wide axial areas.
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Valve ultrastructure of two species of the diatom genus Gomphonema Ehrenberg (Bacillariophyta) from Yunnan Province, China
Fottea, 2020Co-Authors: Yan Liu, John Patrick Kociolek, Yawen FanAbstract:We describe valve ultrastructure of two species of the freshwater diatom genus Gomphonema from a stream and Lugu Lake in Yunnan Province, China, and describe one of these two species as new to Science. Gomphonema emines Skuja was described over 80 years ago. This large, multistigmate species has uniseriate striae without occlusions, large pseudosepta and septa, and internal stigma openings that are round, positioned within ellipsoidal depressions on the extended central nodule. In these features it is distinguished from most of the 'typical' species of the genus. Gomphonema yunnaniana Y.Liu et Kociolek sp. nov. has biseriate striae without occlusions, a large, round external stigma opening and an internal stigma opening that is elevated and contained within a lip-like structure. In these features it is distinguished from the 'typical' species of the genus. We compare these two putatively endemic species from Yunnan with other species groups of the genus.
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One new Gomphonema (Bacillariophyta) species from Yunnan Province, China
Phytotaxa, 2018Co-Authors: Ziyi Jiang, John Patrick Kociolek, Yan Liu, Yawen FanAbstract:During an investigation of the diatom biodiversity of Yunnan Province, one new Gomphonema species was observed from a plateau wetland / nature reserve area associated with Lashi Lake. The new species resembles members of the Gomphonema acuminatum complex, possessing a distinctive outline where the tumid center of the valve is as wide or wider than the headpole. The swollen middle portion of the valve extends more towards both poles than in other taxa in this species group. We describe the morphological features of the new taxon based on LM and SEM observations. This is another report of a new Gomphonema species from Yunnan Province, China; recently a new taxon in this species complex was also described from this Province.
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A new species of Gomphonema (Bacillariophyta) from Xingkai Lake, China
Phytotaxa, 2014Co-Authors: Yan Liu, Patrick Kociolek, Yawen FanAbstract:During an extensive survey of diatoms from Xingkai Lake, China, one unusual species of the genus Gomphonema was discovered. Detailed morphology of this species is presented using light (LM) and scanning electron microscopy (SEM). These specimens are described as new and named Gomphonema subinsigniforme sp. nov. It is distinguished from other known species of Gomphonema by its shape, being tumid at the centre of valves, with acute headpole, and narrow rounded footpole. Morphological features and ecological parameters of this species are compared to others in the genus.
Yan Liu - One of the best experts on this subject based on the ideXlab platform.
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One new Gomphonema Ehrenberg (Bacillariophyta) from Guangxi Zhuang Autonomous Region, China
Phytotaxa, 2020Co-Authors: Fan Zhang, John Patrick Kociolek, Yan Liu, Maxim Kulikovskiy, Yawen FanAbstract:A new Gomphonema species is described from the Shiwan Mts. in Guangxi Zhuang Autonomous Region, Southwest China. This new species differs from other known members of the genus Gomphonema by its linear-lanceolate shape, wide axial area, slit-like areolae openings, one short spine at the headpole externally, and large pseudoseptum at each end internally. Morphological features of the new species are detailed with light and scanning electron microscopy. Comparisons with other similar species are made. This species appears to be closely related to other species of this genus possessing wide axial areas.
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Valve ultrastructure of two species of the diatom genus Gomphonema Ehrenberg (Bacillariophyta) from Yunnan Province, China
Fottea, 2020Co-Authors: Yan Liu, John Patrick Kociolek, Yawen FanAbstract:We describe valve ultrastructure of two species of the freshwater diatom genus Gomphonema from a stream and Lugu Lake in Yunnan Province, China, and describe one of these two species as new to Science. Gomphonema emines Skuja was described over 80 years ago. This large, multistigmate species has uniseriate striae without occlusions, large pseudosepta and septa, and internal stigma openings that are round, positioned within ellipsoidal depressions on the extended central nodule. In these features it is distinguished from most of the 'typical' species of the genus. Gomphonema yunnaniana Y.Liu et Kociolek sp. nov. has biseriate striae without occlusions, a large, round external stigma opening and an internal stigma opening that is elevated and contained within a lip-like structure. In these features it is distinguished from the 'typical' species of the genus. We compare these two putatively endemic species from Yunnan with other species groups of the genus.
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One new Gomphonema (Bacillariophyta) species from Yunnan Province, China
Phytotaxa, 2018Co-Authors: Ziyi Jiang, John Patrick Kociolek, Yan Liu, Yawen FanAbstract:During an investigation of the diatom biodiversity of Yunnan Province, one new Gomphonema species was observed from a plateau wetland / nature reserve area associated with Lashi Lake. The new species resembles members of the Gomphonema acuminatum complex, possessing a distinctive outline where the tumid center of the valve is as wide or wider than the headpole. The swollen middle portion of the valve extends more towards both poles than in other taxa in this species group. We describe the morphological features of the new taxon based on LM and SEM observations. This is another report of a new Gomphonema species from Yunnan Province, China; recently a new taxon in this species complex was also described from this Province.
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A new species of Gomphonema (Bacillariophyta) from Xingkai Lake, China
Phytotaxa, 2014Co-Authors: Yan Liu, Patrick Kociolek, Yawen FanAbstract:During an extensive survey of diatoms from Xingkai Lake, China, one unusual species of the genus Gomphonema was discovered. Detailed morphology of this species is presented using light (LM) and scanning electron microscopy (SEM). These specimens are described as new and named Gomphonema subinsigniforme sp. nov. It is distinguished from other known species of Gomphonema by its shape, being tumid at the centre of valves, with acute headpole, and narrow rounded footpole. Morphological features and ecological parameters of this species are compared to others in the genus.
J. Patrick Kociolek - One of the best experts on this subject based on the ideXlab platform.
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Morphological investigation and description of two new Gomphonema Ehrenberg (Bacillariophyta) species from India and Vietnam with biogeographical comments
Phytotaxa, 2020Co-Authors: Samadhan Pardhi, J. Patrick Kociolek, Anton Glushchenko, Maxim Kulikovskiy, Anbukkarasu Vigneshwaran, Balasubramanian KarthickAbstract:Two new species of Gomphonema Ehrenberg are described based on light and scanning electron microscopical observations. These are Gomphonema kallarense sp. nov. found in India and G. kezlyae sp. nov. found in India and Vietnam. We also report and document the morphology and variability of G. doonense from Vietnam, a species previously described from India based on a limited number of valves. Both G. doonense and G. kallarense have striae composed of doubly-punctate striae that are without occlusions, while G. kezlyae has striae with single rows of areolae that have external occlusions giving the impression of C-shaped openings. Our investigation shows that India and Vietnam share some species in common, adding additional evidence that the biogeography of freshwater diatoms from the tropics warrants future investigation.
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Two multi-stigmate Gomphonema species of Africa: Gomphonema kalahariense (nom. nov., stat. nov.) and Gomphonema chemeron (sp. nov.)
Phytotaxa, 2020Co-Authors: Jeffery R. Stone, J. Patrick Kociolek, Karlyn S. WestoverAbstract:The taxonomy and morphology of two taxa of the diatom genus Gomphonema with multiple stigmata from fossil localities in Africa are considered. Light and scanning electron microscopy as well as quantitative analysis of valve shape suggest two taxa are present in these collections. One of them, previously described as Gomphonema ventricosum var. africana, has 2–4 stigmata and conforms well with the original illustration of this taxon by Reichelt. However, this taxon does not appear to be closely related to G. ventricosum, and is a species in its own right, so a new name, G. kalahariense nom. nov., stat. nov. Jeff.R.Stone & Kociolek is proposed. This species is known from modern and fossil locations in Africa. A second species, Gomphonema chemeron Jeff.R.Stone, Westover & Kociolek sp. nov. is described from diatomite deposits of the Baringo Basin, Kenya, that are approximately 2.6 million years of age. This species, with 3–7 stigmata, has a distinctive shape and is easily distinguished from G. kalahariense. We compare these species with other multi-stigmate members of Gomphonema, including G. krammeri Reichardt, a fossil species described from Mexico and Cuba.
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Gomphonema wuyien sis sp. nov. , a new freshwater species (Bacillariophyceae) from Wuyi Mountains, China
Phytotaxa, 2018Co-Authors: Wei Zhang, J. Patrick Kociolek, Ting-ting Zhao, Li-qing WangAbstract:During a survey of freshwater diatoms from Xingjiang River in the north region of the Wuyi Mountains, Jiangxi Province, China, a new Gomphonema species, Gomphonema wuyiensis sp . nov ., was recorded. A detailed morphological description of G . wuyiensis is herein presented, based on light and scanning electron microscopy. LM and SEM micrographs show the size ranges and ultrastructural details of the new species. Gomphonema wuyiensis sp . nov . is characterized by valve outline asymmetrical to the apical axis. In addition, the valve outline on the primary side strongly tapers from the middle part to the footpole, and less strongly on the secondary side. In addition, distinctive morphological features and ecology of the taxon are discussed.
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The genus Gomphonema (Bacillariophyta) in Rara Lake, Nepal: taxonomy, morphology, habitat distribution and description of five new species, and a new record for Gomphoneis qii
Diatom Research, 2018Co-Authors: Ingrid Jüttner, Zlatko Levkov, David M. Williams, J. Patrick Kociolek, Smriti Gurung, Anu Gurung, Chhatra Mani Sharma, Luc EctorAbstract:During the first study of the diverse diatom assemblages in Rara Lake, the largest lake in Nepal, 11 species of Gomphonema, belonging to six morphological groups, and Gomphoneis qii could be invest...
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New Freshwater Gomphonemoid Diatoms from Streams in the Sierra Nevada Mountains, California, USA
Phytotaxa, 2016Co-Authors: Rosalina Stancheva, Robert G. Sheath, J. Patrick KociolekAbstract:Light and scanning electron microscopic observations of three new species of freshwater gomphonemoid diatoms are presented from mountain streams in California: Gomphonema californicum sp. nov ., Gomphonema sierrianum sp. nov . , and Gomphoneis oreophila sp. nov. Two of the species have morphological novelties related to the structure of the areolae, which are discussed in comparison with similar taxa. Gomphonema californicum shows a variety of areolar morphologies (i.e. lineola-like, c-shaped, and circular) within a single uniseriate stria. Unique to Gomphoneis oreophila, a member of the Herculeana subgroup, are the uniform areolae with circular openings without apparent occlusions. All of these species are distributed in remote streams of the Sierra Nevada Mountains of California, suggesting there are still new species to be found in this biodiversity-rich region.
Patrick Kociolek - One of the best experts on this subject based on the ideXlab platform.
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Morphological and molecular investigation of Gomphonema longissimum and related taxa from Malili lakes (Indonesia) with comments on diatom evolution in ancient lakes
European Journal of Phycology, 2019Co-Authors: Maxim Kulikovskiy, Anton Glushchenko, Elena Kezlya, Yevhen Maltsev, Irina M. Kuznetsova, Dmitry A. Kapustin, Sergei Sidelev, Evgeniy Gusev, Natalia Shkurina, Patrick KociolekAbstract:Four species of Gomphonema described by Hustedt with fusiform valve shape are studied for the first time using SEM. G. longissimum Hustedt, G. angustissimum Hustedt, G. woltereckii Hustedt and G. s...
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Gomphonema grande sp. nov., a new diatom (Bacillariophyta) from the Democratic Republic of the Congo, Tropical Africa
Phytotaxa, 2016Co-Authors: Balasubramanian Karthick, Patrick Kociolek, Jonathan C. Taylor, Christine CocquytAbstract:Gomphonema grande sp . nov . is described from a single sample collected from the Congo River Basin, Tropical Africa. The morphological features of the new species are described and documented through light microscopy and scanning electron microscopy analyses. Gomphonema grande differs from most species of the genus by its relatively large size, robust valves, unique shape, and distinctive suite of valve features such as a labium-shaped internal stigma opening. Further discussion on the diverse nature of certain characters in the genus Gomphonema is presented.
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Two new species of Gomphonema (Bacillariophyceae) from Doon Valley, Uttarakhand, India
2015Co-Authors: Balasubramanian Karthick, Patrick Kociolek, Rachna Nautiyal, Tv RamachandraAbstract:This paper describes two new Gomphonema species from the lesser Himalayas, India, with their valve morphology using light and scanning electron microscopy. The two species, Gomphonema juettnerii sp. nov. and G. doonensis sp. nov., were found in Nalota stream in Doon Valley of Uttarakhand State. Main features of G. juettnerii are valve outline, shape of the areolae and striae pattern and presence of stigma. Main features of G. doonensis are rounded headpole, striae made by doubly punctate striae and features in central area. A detailed discussion on doubly punctate striae in members of gomphonemoid diatoms is presented.
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A new species of Gomphonema (Bacillariophyta) from Xingkai Lake, China
Phytotaxa, 2014Co-Authors: Yan Liu, Patrick Kociolek, Yawen FanAbstract:During an extensive survey of diatoms from Xingkai Lake, China, one unusual species of the genus Gomphonema was discovered. Detailed morphology of this species is presented using light (LM) and scanning electron microscopy (SEM). These specimens are described as new and named Gomphonema subinsigniforme sp. nov. It is distinguished from other known species of Gomphonema by its shape, being tumid at the centre of valves, with acute headpole, and narrow rounded footpole. Morphological features and ecological parameters of this species are compared to others in the genus.