A revision of the Fragilaria pectinalis-complex in Europe (Bacillariophyceae, Fragilariaceae) with the description of a new species

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.

In the present study, two new species of Nitzschia Hassall, Nitzschia pusilluhasta sp. nov. and Nitzschia australodesertorum sp. nov. are described from reservoirs in the state of São Paulo southeast Brazil. The morphology of the new species was analysed using light and electron microscopy. Nitzschia pusilluhasta is distinguished from morphologically related species by its valve outline, the shape of apices and fibulae, the absence of a gap between central fibulae, and the density of striae and areolae. Nitzschia australodesertorum differs from morphologically similar species in its valve outline, the shape of apices and fibulae, the presence of a gap between the central fibulae, and the density of fibulae and striae. The morphology and ecology of the new species are discussed and compared with morphologically related taxa. Information on the co-occurrence of other diatom species in the samples is also provided.

During a revision of the genus Fragilaria in Europe, two unknown Fragilaria taxa were observed in Erken Lake, Sweden, that showed some resemblance to Fragilaria perminuta, a species described in the nineteenth century from the Great Lakes in the United States. The type material of Synedra perminuta from Lake Erie, U.S.A. (Grunow sample 2592) was analysed. Detailed morphological analysis, using both light and scanning electron microscope observations and comparison with the type material, showed that both taxa from Sweden should be described as new species: Fragilaria goeyersiana sp. nov. and F. vandevondeliana sp. nov. The separation of the two taxa is based on valve outline, shape of the apices and stria density. Comparisons are made with similar taxa and brief notes on their ecology are added.

During our investigations on the taxonomy of diatoms of clear water habitats in the western Pará region, we found three interesting, previously undocumented Neidium species. This study was based on samples taken from different habitats (plankton and sediment) in the Arapiuns and Tapajós Rivers, as well as three lakes. Based on light and scanning electron microscope observations, three new Neidium are distinguished from one another and their congeners by differences in valve outline, stria density, striation pattern, number and position of longitudinal canals and external proximal raphe endings. Furthermore, we provide formal descriptions of these new species and compare them with others similar species. We also discuss variation in several features of taxa currently assigned to the genus Neidium.

A new freshwater diatom recovered from modern and subfossil sediments of Lake Apastepeque in El Salvador, Achnanthidium neotropicum sp. nov., is described based on light and scanning electron microscopy observations. The species is characterized by valves with linear, sometimes centrally constricted (mainly in large cells), outlines, broadly rounded to subrostrate apices, and often rectangular fascia. Striae are composed of 3–4 rounded to slit-like areolae. It can be separated from similar species by valve outline, together with striae density, and number of areolae per stria. Based on the straight distal raphe endings this species can be assigned to the A. minutissimum complex. The new species is compared to morphologically resembling species from the genus Achnanthidium Kützing.

Caloneis mendosina var. mendosina, Caloneis mendosina var. minor and Caloneis quilinensis from slides of the Frenguelli Collection deposited at the Herbarium of the División Ficología ‘Dr. Sebastián A. Guarrera’ (LPC), were investigated using light microscope (LM). Unmounted material related to these slides was observed using the scanning electron microscope (SEM). Specimens of both varieties of C. mendosina found in the original material show a continuous range of size and stria density, and are ultrastructurally similar; thus the taxa are considered conspecific. Specimens of C. quilinensis found in the original material show more variability than described in the protologue. A continuous range of size, stria density, shape of the frustules and valve outline was observed between C. mendosina and C. quilinensis. Additionally, ultrastructural comparison of both taxa showed numerous features in common including shape of the valve surface, morphology of the valve mantle, shape of the axial area, shape of the fascia, position of the raphe, morphology and orientation of the external central and distal raphe fissures, and size and position of the elliptical apertures of the alveolate striae. The evidence that there is no morphologic and morphometric discontinuity between these Frenguelli taxa and that they come from similar diatomaceous earth deposits, justify considering them conspecific. Based on the principle of priority the correct name of the species is Caloneis mendosina. The description of C. mendosina was emended, a lectotype slide was selected, and a comparison with some allied species was conducted.

A new species was discovered in Taihang Valley, Shanxi province, China. It shared the typical characteristics of the genus Chamaepinnularia, such as chambered striae, vela-covered areolae and small frustules. Valves of Chamaepinnularia taihangensis sp. nov. are linear-lanceolate with capitate apices. Valve margins showed distinct triple curvatures in light microscopy. Axial area and central area narrow, rhombic. The new species was compared with the four related taxa, C. hassiaca, C. justa, C. krookiformis and C. soehrensis. These species differed from the new species in valve outline, valve size, stria density and the shape of the central area. The details of the valves as shown by light and scanning electron microscopy are described. This new species occurs in benthic and epiphyte habitats. We discuss the ecological breadth and systematic position of the genus Chamaepinnularia.

During a survey of the non-marine diatom flora of King George Island (South Shetland Islands), an unknown Humidophila taxon was recorded. Detailed light and scanning electron microscopy observations indicated that the unknown taxon could not be identified based on the currently available literature. The new species is described as Humidophila komarekiana sp. nov. and is characterized in having strictly linear valves with parallel margins and broadly rounded, never protracted apices, a filiform raphe with almost indistinct, straight proximal and distal raphe endings. The striae are composed of one, irregularly shortened areola. The mantle areolae are interrupted at the apices. The new species is compared with similar taxa in the Antarctic Region and worldwide. Notes on the ecology of the new species are added.

Scanning Electron Microscope Studies on the Leaves of Hepaticae. I. Ptilidiaceae, Lepidoziaceae, Calypogeiaceae, Jungermanniaceae, and Marsupellaceae

In this study, three new species of the genus Gomphonema from freshwater lakes of the lower reaches of Yangtze River, China. They include G. qii sp. nov. from Yangcheng Lake, G. poyangense sp. nov. from Poyang Lake, and G. longganense sp. nov. from Longgan Lake, and all of these new species were collected on stone. We detailed morphological features of these new species are described based on light microscopy (LM) and scanning electron microscopy (SEM), and the LM and SEM photographs illustrate the size ranges and particular ultrastructure of these new species. G. qii sp. nov. with clavate-lanceolate valves, bluntly rounded headpole and narrowly-rounded footpole, narrowly axial area, uniseriate striae. G. poyangense sp. nov. with clavate-lanceolate valves, rounded headpole and narrowly-rounded footpole, broadly rhombic-lanceolate axial area, short uniseriate striae, c-shaped to irregularly shaped areolae. G. longganense sp. nov. with slightly heteropolar, linear-lanceolate valves, protruded headpole and rounded footpole, narrowly axial area, variously-shaped areolae. Additionally, three new species only have one stigma per valve. We compare these new species with other similar species of Gomphonema based on valve outline, shape of the axial and center areas, and striae density. While their valve features and symmetry easily assign them to Gomphonema, their differences with 'core' species of the genus are discussed.

In the late eighteenth century there began a great debate on popular culture that extends down to our own time but that has yet to find its historian.1 Literary writers started to face directly the question of the cultural and political meaning of the growing market for printed goods for they were becoming more dependent on a relatively wide middle-class and partly artisan audience (first present in eighteenth-century England), and were experiencing the erosion of the privately endowed aristocratic patronage system. Leo Lowenthal showed thirty years ago how important this was in the origin of the modern debate on "mass culture."2 The late eighteenth and early nineteenth centuries saw also, however, several developments that began to polarize attitudes amongst the intellectual elite toward the traditional artisan and peasant culture that still predominated in Europe. Three developments, in particular, are worth citing here. First, widening educational and cultural differences between upper social strata and the common people after the mideighteenth century, coupled with the growing threat of rebellious rural and urban crowds to aristocratic politics in the age of the "democratic revolution," brought on sustained conservative alarm at the "vile multitudes."3 Second, the initial rise of an ascetically-minded business class and the beginnings of "progressive" economic liberalism, especially in western Europe, saw attacks on a traditional popular culture seen as unfit for the making of a modern civilization requiring prudent, industrious values.4 Third, the spread of a populist romanticism aimed against "enlightened" gentility brought many intellectuals to praise peasant and artisan "folk" against courtly or bourgeois culture in the years between the German Sturm and Drang (the 1770s) and the Revolutions of 1848 1849.

In the late twentieth and early twenty-first centuries we have grown used to using the term “fellow creatures” to refer to non-human animals — from dogs and cats to horses and hippopotamuses. In the late seventeenth and early eighteenth centuries the term was also used to refer to non-human animals. But from the late eighteenth century (when the term began to be used for several decades with much greater frequency), through the nineteenth century, and through most of the twentieth century too, “fellow creature” was a term used to connect like to like — horses to horses, sheep to sheep, or, much more commonly, humans to other humans. Why the change in the late eighteenth century? And why the further change in the late twentieth century? This paper argues that political activism played a key role — and that the activism of those leading the fight against cruelty towards animals in the late eighteenth and early nineteenth centuries was implicitly in competition with the struggles to improve the lot of black Africans, the poor, women, and other oppressed categories of humans — causes that sought to end the treatment of these groups as “no better than animals.”

During a survey of diatoms present in tidal pools on the coasts of Livingston Island (South Shetland Islands), we found several populations, belonging presumably to the Antarctic endemic Craspedostauros laevissimus. Further analyses using light microscopy revealed that the populations show differences in stria density. Following scanning electron microscopy observations, only part of the investigated populations could be assigned to C. laevissimus, whereas the others are sufficiently morphologically different based on stria density and their cribrate areolae structure to be described as a new species: Craspedostauros confusus sp. nov. The new taxon is compared with known, morphologically similar, Craspedostauros taxa. The paper presents morphological and ecological data for both taxa discussed in the study. A detailed survey of the early Antarctic literature showed that the Craspedostauros taxa in Antarctica have convoluted taxonomic histories and that the new taxon has likely been hidden for long within the variability of C. laevissimus.

Three new subaerial species of Achnanthidium are examined and described from a karst landform of central-south China based on light and scanning electron microscopy observations, and are compared with similar taxa worldwide. A. mediolanceolatum sp. nov. is elliptical-lanceolate, not linear-lanceolate as is more typical in this genus, as well as having a bow-tie shaped central area on the raphe valve and a large lanceolate axial area on the rapheless valve, features which together make it easy to distinguish this species from others. A. parvulum sp. nov. and A. guizhouensis sp. nov. are linear-elliptical in shape, which is more common for Achnanthidium and they differ from other species mainly in size, raphe, density of striae and shape of the central area. We compared these three new species with morphologically-similar taxa, and present their ecological settings and distributions as well. The relationship between Achnanthidium and Psammothidium is discussed, and the data from these new species from Guizhou presented herein suggest the two genera are difficult to separate.

During analyses of surficial sediments from Lake Fuxian in Yunnan Province, Southwest China, Navicula fuxianensis sp. nov. was recorded and described by light and scanning electron microscopy analysis. The new species is characterized by a lateral, slightly undulate raphe and lineolate striae, as well as variously shaped areolae and an internally-elevated raphe system. Navicula fuxianensis sp. nov. shares features with other species in this genus, similar to N. gongii in valve outline and stria arrangement, respectively. However, the species can be easily distinguished from taxa which it resembles by the density of striae and lineolae, as well as the structure of the central area and areolae. The new Navicula species from Lake Fuxian has unique sets of characters that distinguish it from all previously described Navicula species. Brief notes on the associated diatom flora and its ecological preferences are added.