ABSTRACT The French part of the Rhin-Meuse basin is quite heterogeneous due to the broad variability in pH and conductivity ranges of its rivers and streams. Parts of the basin are characterized by the presence of typical natural or anthropogenically induced brackish environments, showing a typical diatom flora. Since many brackish diatom species observed in these particular environments are often only poorly illustrated in literature used for biomonitoring, the present paper tends to fill this gap in our knowledge. Therefore, we illustrate in this work a large number of brackish taxa such as Cyclotella scaldensis, Skeletonema potamos, Thalassiosira gessneri, T. lacustris, T. weissflogii, Achnanthes secretitaeniata, Bacillaria paxillifera, Berkeleya rutilans, Entomoneis paludosa, Halamphora coffeaeformis, Haslea spicula, Nitzschia amplectens, N. aurariae, N. frequens, N. inconspicua and N. thermaloides. Additionally, one new species, Tabularia massenana sp. nov. is described based on detailed LM and SEM observations.

ABSTRACT The only Caryota species native to Singapore, C. mitis is an important ecological resource for a diversity of fauna. However, little is known about the autecology of this charismatic, commonly cultivated palm. This is the first study that focuses on the autecology of C. mitis in Singapore, investigating the following ecological attributes: (1) their population demography; (2) differences in densities of C. mitis individuals between forest edges and interiors, and different vegetation types in secondary forests of Singapore; (3) fruit set; and (4) resource utilization for food and shelter by fauna in Singapore. Our results demonstrate that C. mitis thrives under disturbance, with significantly more individuals found in highly disturbed vegetation type, and more juveniles to adults along forest edges compared to the interior. Fruit set of C. mitis was estimated to be 31.88%, with each infructescence producing on average 805 fruits (n= 15). Eighteen species of insects over four orders (Hymenoptera; Coleoptera; Lepidoptera; and Hemiptera) were observed to utilize C. mitis for either food or shelter, and camera trapping (n = 562 trap nights) revealed five vertebrate taxa foraging on the fruits – pink-necked green pigeon (Treron vernans), oriental pied hornbill (Anthracoceros albirostris), common palm civet (Paradoxurus musangus), long-tailed macaque (Macaca fasicularis) and plantain squirrel (Calloscirurus notatus). The ecological importance of C. mitis in maintaining food resources in the highly fragmented landscape of Singapore has important implications in reforestation and rehabilitation efforts in the region, considering their potential to thrive in disturbed habitats and along forest edges.

End of March 2019, the Luxembourg Institute of Luxembourg (LIST) organized the 12th Central European Diatom (thereafter CED) Meeting in Belvaux, Grand Duchy of Luxembourg (Ector et al. 2019) with t...

ABSTRACT The article presents the European distribution of Salvia hispanica, or chia, a plant species native to Central America. The species is very popular as a nutritional additive in the diet of the western world. The first reports of species occurrence are from 2013 and it is now reported in eight European countries. We present the ecology, habitat, possible pathways of introduction and limits of potential invasion. We assessed the species invasive potential using three different risk assessment methods.

ABSTRACTA new Lucanicum species, L. ashworthianum Majewska, K.Robert & Van de Vijver sp. nov., was found in multiple samples of biofilm growing on loggerhead sea turtles Caretta caretta and their symbiotic barnacles Chelonibia testudinaria collected on the beaches of Kosi Bay, eastern coast of South Africa, during the two nesting seasons (the austral summers of 2017/2018 and 2018/2019). The new species possesses several features typical of the genus Lucanicum, including the uniseriate striae composed of one large macroareola, the presence of large apical slit fields and transapically elongated rimoportulae at both poles, and a cingulum composed of numerous open, doubly perforated copulae. It differs from the only other Lucanicum species known to date, the coral-associated L. concatenatum, in having considerably smaller cells with clearly rostrate or sub-capitate apices and internal rimoportula opening composed of a C-shaped inner lip and an oval, flap-like outer lip – a feature not observed previously in Lucanicum. Based on these new observations, an amendment of the genus description is proposed.

ABSTRACTCocconeis Ehrenberg is a monoraphid diatom genus included in the Family Cocconeidaceae. It occurs in marine and freshwater environments, living attached to a substrate by the raphid valve. Through the documentation of the taxa found in LM and SEM analyses, this study aims to increase the knowledge about freshwater Cocconeis species occurring in Brazilian waters. In addition, one new species is formally described here. Seven samples were chosen from a total of 346 samples investigated for monoraphid diatoms in São Paulo state, Brazil, due to their representativeness for Cocconeis biodiversity. These samples include periphytic, metaphytic and surface sediment materials. One sample from Ivory Coast was also analysed to compare a similar taxon with the taxa found. The biodiversity and the occurrence of the genus Cocconeis were low in our study material (nine taxa) despite the great amount of samples analysed for monoraphid taxa. Nevertheless, one taxon was considered a new species, being described here. Finally, this study was based on morphological characters of the frustule observed in LM and SEM analysis, showing the importance of both to better understand the variability of each species and to separate similar taxa.

ABSTRACTWe report here the occurrence of petrified wood resembling the modern dipterocarp Dryobalanops from the Neogene (late Miocene) of the Bengal Basin, India. We have determined the taxonomic position by comparing its anatomical features with similar extant and fossil specimens and have finally identified this late Miocene wood as Dryobalanoxylon neosumatrense. The record of this new member of Dipterocarpaceae indicates that it was present in a tropical, warm and humid eastern India during the late Miocene. Considering all earlier fossil records of Dryobalanops we suggest that this taxon was a common forest element in Asia during Neogene-Quaternary time. We also review in detail the biogeographic history of this taxon and suggest a possible migration route.

ABSTRACTLand use changes in the northern Mediterranean basin threaten our ability to conserve its habitats and species. Reduced grazing has led to local declines in grassland species and colonization by forest species leading to conservation actions aimed at restoring open habitats. Recently, populations of Gagea lacaitae, a bulbous species typical of Mediterranean open xeric grasslands, have been discovered in forest clearings, an unexpected habitat for this species. Here, we surveyed 48 plots to characterize and compare the ecological niche of G. lacaitae growing in both open xeric and forest clearing habitats. We recorded floristic composition and plant cover and collected soil samples to measure water retention capacity, pH, organic matters and conductivity. Open xeric grasslands and forest clearings differ in plant cover, community composition, and microhabitat structure but not in plant diversity, mean soil conditions, or G. lacaitae cover. Key similarities in conditions allow this species to persist in woodlands that heterogenous enough to include clearings. Such habitats have value for conserving this species and should be sustained.

ABSTRACTWe study the phylogeography of the series Fissa species in the Iberian Peninsula. This group constitutes a complex formed by three Iberian endemic and threatened taxa with restricted distribution ranges and relatively small population sizes. We amplify and sequence two plastid regions, trnS-trnG and psbA-trnH from 15 sampling locations (n = 45). A total of 15 haplotypes are detected. The median-joining phylogenetic network shows two main haplotype lineages: one western corresponding to the western taxon, D. fissum subsp. sordidum, and the other eastern corresponding to eastern taxa D. bolosii and D. mansanetianum. AMOVA analysis with 94.32% of the total variation and SAMOVA analysis with a Fct value of 0.943 support the presence of these well-defined lineages. We report high values of total gene diversity (hT = 0.959). Haplotype diversity within populations is low (hS = 0.311). On the contrary, differentiation among populations (GST = 0.675) and Fixation Index (FST = 0.989) are high. These values mean that gene flow among populations is limited. Estimation of divergence times shows that the split between D. fissum subsp. sordidum and the two other taxa (D. bolosii and D. mansanetianum) took place during the transition between Pliocene and Pleistocene (approximately 2.67 Ma). Negative Tajima’s D-values test (Tajima’s D = -0.108, P ≥ 0.1) and unimodal mismatch distribution suggest expansion range for D. fissum subsp. sordidum. We advocate to draw up recovery plans for series Fissa species in the Iberian Peninsula, especially for D. fissum subsp. sordidum.

ABSTRACTThe Balkan species Thymus jankae is documented for the first time from Ukraine on Mount Chorna Hora (Vynohradiv town, Transcarpathian region), which is ca. 300 km northwards from its main range. This species locality has long been overlooked due to misidentification of its early collections with other Thymus taxa. Despite its ambiguous taxonomy, available morphological, caryological, biogeographical, and molecular data support a species rank of Th. jankae and suggest its ancestral position within the Thymus praecox-group. Morphology and chromosome count (2n = 56) of plants from Ukraine are congruent with the data available for Balkan populations. Phytosociological survey of Th. jankae locus in Ukraine shows the species to be affiliated with the associations Alysso alyssoidis-Sedetum and Festucetum pseudodalmaticae, as well as a community physiognomically close to the association Potentillo heptaphyllae-Festucetum rupicolae. The first two associations are parts of biotopes (6110 and 6240) with priority status according to Annex I of the Habitats Directive (92/43/EEC) and represent respectively a pioneer community and subpannonic meadow steppe grassland with evident southern European relationships. Most likely, the discovered locality of Th. jankae is a relict northern outpost created by extinction of a part of the former species range, although its anthropogenic origin should not be also excluded. Conservation of Th. jankae in Ukraine on the national level is discussed.