Genus Nupela Research Articles

Preliminary molecular phylogeny of the diatom genus Nupela with the description of a new species and consideration of the interrelationships of taxa in the suborder Neidiineae D.G. Mann sensu E.J. Cox

Molecular investigation of genera Nupela and Brachysira is conducted using strains from Indonesia and Vietnam. New species from the genus Nupela indonesica sp. nov. is described using combined approach. Nupela lesothensis (Schoeman) Lange-Bertalot is investigated using molecular data too. Phylogenetic analysis shows that Nupela and Brachysira are not closest genera. Morphology of Nupela and it differences from Brachysira is discussed. The genus Nupela is differs from all other diatom taxa by having coalescent hymenes ouside of areolae but not inside. Facultative development of raphe between different Nupela species is discussed.

Nupela brevistriata sp. nov. – a new, terrestrial diatom species from Southeast Asia

The genus Nupela Vyverman & Compère comprises 81 species, which have been reported from different continents. This study presents the morphological characteristics of Nupela brevistriata sp. nov. found in moss samples collected from soil and tree bark in Southeast Asia, on the islands of Palambak and Sumatra. Light and scanning electron microscope observations are presented and a formal description is offered for the new species. Nupela brevistriata sp. nov. is characterized by the valves having very short striae, capitate apices and a large central and axial area; it occurred rarely (<2%) in assemblages dominated by typically terrestrial species, such as members of Ferocia Van de Vijver & Houk, Angusticopula Houk, Klee & H. Tanaka, Luticola D.G. Mann, Humidophila Lowe et al. and Hantzschia Grunow.

Виды рода Nupela Vyverman &amp; Compère в водоемах Крайнего Севера Западной Сибири и Дальнего Востока (Россия)

Виды рода Nupela Vyverman &amp; Compère в водоемах Крайнего Севера Западной Сибири и Дальнего Востока (Россия)

Species of the Genus Nupela Vyverman and Compere (Bacillariophyta) in the Water Bodies of the Far North of Western Siberia and Russian Far East

The morphology, taxonomy and distribution of species of the genus Nupela were analyzed on the base of literature data and the results of SEM study of the phytoplankton samples collected in the water bodies of the Far North of Western Siberia and Far East of Russia. At present, 20 representatives of the genus Nupela are cited for Russia; most of them are rare species, including 9 Baikal endemics. The ranges of the dimensional characters of the species found differ from those in the protologues testifying their wider morphological variability. A number of species of the genus (N. imperfecta, N. impexiformis, N. neogracillima) were first cited for the water bodies of the Far North of Western Siberia and the Far East. Nupela impexiformis and N. impexa have coinciding dimensional ranges and similar morphology of raphe and rapheless valves that makes it possible to refer the latter to the synonym of N. impexiformis and extend the diagnosis of this species.

Nupela major sp. nov., a new diatom species from Maolan Nature Reserve, central-south of China

Nupela major sp. nov., a new species of the diatom genus Nupela, is described from Maolan Nature Reserve, Guizhou Province, China. Observations were made using light and scanning electron microscopy documenting the size, shape and ultrastructure of the new species. Valves of the monoraphid frustules are elliptical-lanceolate with more or less cuneate, subtlety protracted ends. The raphe valve has a linear-lanceolate axial area and an irregularly-shaped central area. Striae appear intermittent or disrupted. The rapheless valve has a linear-lanceolate axial area widening in the center to form an asymmetrical central area that can in some specimens reach to the valve margin. The rapheless valve has a contoured valve face, with deep indentations in the axial area. The species is assigned to Nupela by virtue of its external occlusions on the areolae, and compared with similar species in the genus. The new species is found on stones beneath a waterfall and associated with a moss community.

Nupela (Bacillariophyceae) in littoral rivers from south Brazil, and description of six new species of the genus

The genus Nupela is characterized mainly by structure of the areola and raphe system. Many species were described from tropical regions; however, few studies have been conducted on Brazilian environments. The goal of this article is to identify and describe the morphology of Nupela species, under light and electron microscopy, found in the rivers of the Atlantic Forest from southern Brazil. Twelve species were found, including six described as new: Nupela amabilis Tremarin et T. Ludwig, N. difficilis Straube, Tremarin et T. Ludwig, N. kocioleckii Straube, Tremarin et T. Ludwig, N. metzeltinii Tremarin et T. Ludwig, N. praecipuoides Tremarin et T. Ludwig and N. torganiae Tremarin et T. Ludwig, and a new combination, N. bicapitata (Hustedt) Tremarin et T. Ludwig.

Nupela troglophila sp. nov., an aerophilous diatom (Bacillariophyta) from the Bossea cave (NW Italy), with notes on its ecology

Nupela troglophila sp. nov. is described from epilithic and epiphytic samples collected around the artificial lighting system in the Bossea cave, SW Alps (NW Italy). The morphological features of the new species are described and documented through light microscopy and scanning electron microscopy analysis. A comparison with morphologically similar taxa is provided. Nupela troglophila belongs to the group of the small, elliptical-lanceolate species of the genus Nupela. The key feature that distinguishes it from all the other taxa belonging to this genus is the shape of the distal raphe fissures, always laying on the valvar surface, strongly deflected on the same side, but never reaching the valve mantle. The ecological preferences of the most abundant diatom species are explored through the ecological optimum calculation and the Outlying Mean Index (OMI) analysis. Within the Bossea cave, N. troglophila seems to prefer humid and warm sites. The highest abundance was reached on wet walls characterized by low light conditions. Nupela troglophila was generally associated with Humidophila pyrenaica that showed the same pattern of distribution in the cave and similar relative abundance. On the contrary, N. troglophila showed its lowest densities when Humidophila contenta was abundant. Until now, N. troglophila has been recorded only in the type locality.

Nupela species (Naviculales: Bacillariophyceae) from Colombian lowland waters including N. acaciensis nov. sp. and N. catatumbensis nov. sp.

The genus Nupela comprises ca. 50 species that generally have a distribution restricted by bioclimatic frontiers. As part of an integrated analysis of the diatom flora of Colombia, in this study we focused our interest on the genus Nupela from lowland waters. Periphyton samples were collected from 150 sites of lotic water bodies in Colombia, taking into account hidrogeomorfological variability. In each sampling station, periphyton samples were obtained by scraping, and temperature, pH, dissolved oxygen and conductivity variables were measured. Samples were processed by both light microscopy (LM; Carl Zeiss Axio Scope.A1) and scanning electron microscopy (SEM; FEI-Quanta 450 and a Jeol JSM-6360 LV). The genus Nupela was found in 28 sites. Five taxa were identified, described and illustrated from tropical or subtropical environments: N. lesothensis, N. praecipua y N. subpallavicinii; these were new records for Colombia, and N. acaciensis and N. catatumbensis two new species for science. N. acaciensis is characterized by raphe branches of both valves equally long combined with cymbelloid symmetry, striae built by 2 transapically elongated areolae that delimit a longitudinal line at each hemivalve. N. catatumbensis is characterized by the presence of a well developed raphe in both valves; valves lanceolate with subcapitated to capitated ends and cymbelloid symmetry, striae built by 3-4 transapically elongated areolae, interestriae elevated as transapical ribs and internal proximal raphe ends hook-shaped. The genus Nupela was widely distributed in the studied basins but showed different distribution patterns: N. acaciensis and N. subpallavicini had a restricted distribution, while N. catatumbensis, N. lesothensis and N. praecipua had a wider distribution, and were collected in sites with significant variations in their ecomorphology, altitude, temperature, pH and electrolyte content.

Late quaternary Nupela taxa of Retezat Mts (S. Carpathians), with description of Nupela pocsii sp. nov. (Bacillariophyceae)

Abstract Nupela pocsii Buczkó &amp; Wojtal, sp. nov., a new species from the Retezat Mountains (S. Carpathians), is described. High asymmetry (along apical and transapical axes and in raphe pattern) and small dimensions are the most characteristic features of this taxon. Nupela pocsii was found during paleolimnological research in early Holocene sediment of Lake Brazi. Seven other representatives of the genus Nupela were detected in high-resolution diatom analyses of three lake sediment sequences of the Retezat Mts: Nupela fennica (Hustedt) Lange-Bertalot, N. imperfecta (Schimanski) Lange-Bertalot, N. impexiformis (Lange-Bertalot) Lange-Bertalot, N. lapidosa (Krasske) Lange-Bertalot, N. paludigena (R. P. Scherer) Lange-Bertalot, N. vitiosa (Schimanski) Siver &amp; Hamilton and an unidentified Nupela Vyverman &amp; Compere species. Our results suggest high diversity of oligotraphenic species in these mountain lakes during their ontogeny, which began 17,000-15,000 years ago. In addition to the newly described species this is also the first record of N. paludigena in European lakes, although its occurrence was previously documented by SEM and LM from Lake Saint Anna without correct identification.

Transfer of Achnanthes decipiens to the genus Nupela

Achnanthes decipiens Reimer was described from a benthic sample collected from a small stream in South Carolina, USA. Examination of the type material with light and electron microscopy showed that this species belongs to the genus Nupela Vyverman & Compère to which it is transferred. Nupela decipiens (Reimer) Potapova is similar to N. praecipua (Reichardt) Reichardt by the size and shape of the valve and the striation pattern, but differs from it by the large central area on the raphe valve. So far, N. decipiens has been reported from a few slightly acid soft-water streams in eastern North America.

New species and combinations in the genus Nupela from the USA

Several species of Nupela were found in samples collected in 2009 from streams and aerophytic habitats of North-central Pennsylvania. Some of these species appeared either new to science or insufficiently known and, although described earlier, not yet transferred to the genus Nupela. This triggered an investigation of type materials of several Nupela species described in the past, especially those with type localities in the Appalachian region. As a result of this study, two new Nupela species, N. elegantula and N. frezelii are described, while Navicula pennsylvanica, Navicula poconoensis and Achnanthes subrostrata are transferred to Nupela. Examination of type material of Achnanthes subrostrata var. appalachiana showed that this taxon is conspecific with Nupela lapidosa.

Nupela marvanii sp. nov., and N. lapidosa (KRASSKE) LANGE-BERTALOT in Poland with notes on the distribution and ecology of the genus Nupela (Bacillariophyta).

Two species of Nupela were identified in a spring and in a small spring-fed pool in the Polish Tatra Mts, - these were N. lapidosa and Nupela sp. The second species is described as N. marvanii. The new species is characterized by heteropolar, narrowly elliptic valves with capitate apices. Sternum valve has very short, sometimes rudimental raphe branches. Under a light microscope transapical striae are not discernible. Externally both valves are covered with hymen. The central area of sternum valves has irregular silicate thickenings. Proximal raphe fissures are straight and terminate in small pores. Distal raphe fissures double-deflected into the same side of the valve, form ?-shaped structures that extend onto the mantle. Internally visible linear-lanceolate axial area, which forms unilateral fascia on raphe valve, which reaches valve margin. Proximal raphe fissures are T-shaped. Distal raphe fissures are straight, and terminate in small, linear helictoglossa. Sternum valve has large, clearly visible internally, asymmetrically lanceolate central area and discernible externally reinforced median costa. Raphe fissures are strongly reduced, rudimental. The areole are round to elliptical, expanded along the transapical axis, with the wider opening on the external surface. An irregular row of similar areoles is present along pleural side of valve. Both species are documented with LM and SEM micrographs and briefly discussed. The distribution and autecology of 46 Nupela members are summarized.

Notes on the genus Nupela (Bacillariophyceae) including the description of a new species, Nupela scissura sp. nov. and an expanded description of Nupela paludigena

SUMMARYTwo species of the diatom genus Nupela are reported from freshwater lakes situated along the Atlantic Coastal Plain of North Carolina, USA. One of the species, N. scissura sp. nov., is described as new and the description of the other, Nupela paludigena (Scherer) Lange‐Bertalot, is expanded to include a full suite of ultrastructural characters. Nupela scissura is a heterovalvar taxon with one valve having a fully developed raphe identical in structure to those found on other Nupela species. The other valve lacks a true raphe, but presents one to several elongated slits in the apical portion of the sternum. The true identity of the slits, whether they represent a highly reduced raphe, a rudimentary raphe, or neither is unknown. In addition, both valves of a single N. scissura frustule differ in the structure of the axial and central areas. The structure of the areolae and details of the raphe clearly place this species in Nupela. Nupela paludigena (Scherer) Lange‐Bertalot was originally described in the genus Anomoeoneis from acidic and humic localities from the south‐eastern part of the Atlantic Coastal Plain and later transferred to Nupela. Although this species has rarely been reported since its description, our findings indicate that it is a common component of the floras in the Carolina bays of North Carolina. The characteristics currently used to circumscribe taxa within the genus Nupela are discussed in light of published work and our own observations.

NUPELA EXOTICA SPECIES NOVA: UNE DIATOMÉE D'UN AQUARIUM TROPICAL D'EAU DOUCE. AVEC DES REMARQUES SUR LA BIOGÉOGRAPHIE DU GENRE / Nupela exotica sp. nov., a diatom from a tropical freshwater aquarium. With comments on the genus biogeography

A new naviculoid diatom species, Nupela exotica Monnier, Lange-Bertalot & Bertrand spec. nov., has been discovered in a tropical freshwater aquarium near Orléans (France). It is described on the basis of SEM studies, complemented by LM observations. The diatom flora and water characteristics are particular, since taxa from Europe and from tropical zones are associated. Among 54 counted taxa three belong to the recently established genus Nupela. The water of the aquarium is fairly acid, rich in nutrients and mineral content, the specific conductance is moderately high. Biogeography and ecology of N. exotica are discussed and compared with other species of the genus.