The microflora of hypogean environments has been studied increasingly worldwide. However, some sites have hardly been examined or not studied at all; this is the case for the Giant Cave, a Karst show cave located near Trieste, Italy. In the present study we began characterizing the Giant Cave Lampenflora by using a polyphasic approach, focusing, in particular, on three Leptolyngbya-like strains named GR2, GR4, and GR13. Light and electron microscopic observations were carried out and the water-soluble pigment composition was analysed. Phylogenetic reconstruction, based on the 16S rRNA gene and the 16S-23S ITS region, was performed to better understand the taxonomic position of these strains, complemented by 16S-23S ITS secondary structure analysis. Ecological and geographical data for the investigated strains and for the other cyanobacterial strains grouping with them in the phylogenetic reconstructions were also considered. Based on the results, strain GR2 was ascribed to the species Heteroleibleinia purpurascens (Hansgirg) Anagnostidis & Komárek; strains GR4 and GR13 were attributed to a new genus of the family Leptolyngbyaceae, Timaviella Sciuto & Moro, gen. nov., and represented two distinct species: Timaviella circinata Sciuto & Moro and Timaviella karstica Sciuto & Moro.

The distributions of scaled chrysophytes in 22 waterbodies from the eastern portion of Newfoundland, Canada, are described relative to environmental gradients. A rich and diverse flora of scaled chrysophytes was recorded that included 47 species from six genera, Mallomonas (n = 29), Synura (n = 7), Neotessella (n = 1), Chrysosphaerella (n = 2), Spiniferomonas (n = 7) and Paraphysomonas (n = 1). Combined with previous works, 57 species of scaled chrysophytes are now known from Newfoundland. On average, 15 species were recorded from each site, and 34 of the taxa were found in more than 10% of the sites. The most widely distributed species were Mallomonas duerrschmidtiae, M. galeiformis, Synura echinulata, S. sphagnicola, and S. petersenii sensu lato, each found in over 75% of the study sites. Seven additional species were found in over 50% of the localities indicating the rich diversity of the flora. One site is of particular significance as it represents the type locality for three species, including Mallomonas newfoundlandicus sp. nov. described in this communication, and represents the northern-most site harboring the marker taxon, M. binocularis. Expanded descriptions of M. maculata and Spiniferomonas abei are given, and evidence is presented that Synura synuroidea represents two distinct species. Overall, the flora reflects habitats that are acidic, dilute and contain moderate to high concentrations of humic substances. Since many of the species are diagnostic bioindicators, these organisms would provide a valuable resource for future paleolimnological studies aimed at understanding impacts from environmental stressors on Newfoundland lakes.

During an investigation on the diatom communities of volcanic lakes of Northeastern China a new species belonging to the “Cyclotella comta species complex” was observed. This taxon forms relatively large populations in the phytoplankton of Lake Tuofengling Tianchi, a 33m-deep, oligotrophic, crater lake located in Inner Mongolia. In this paper, the valve morphology and ultrastructure of this taxon is described using light and scanning electron microscopy and a new name, Lindavia khinganensis sp. nov., is proposed. A discriminant analysis based on morphological LM and SEM data confirmed that L. khinganensis is distinct from other Lindavia species with a similar morphology such as L. comta (Ehrenberg) Nakov et al., L. radiosa (Grunow) De Toni & Forti, L. balatonis (Pantocsek) Nakov et al., L. praetermissa (Lund) Nakov et al. and L. tenuistriata (Hustedt) Nakov et al. In addition, the seasonal and interannual distribution of L. khinganensis was investigated using sediment trap samples collected over a two-year period. Limnological data from Lake Tuofengling, including water chemistry and temperature recording from a thermistor chain provided complementary information about the ecology of this new species. This species was not found in any other lakes from Northeastern China that we investigated.

Our knowledge of non-native algae in benthic estuarine habitats is relatively poor, especially compared to algal introductions along open shores or on floating structures. Gracilaria vermiculophylla is a widespread macroalgal invader in the temperate estuaries of the Northern Hemisphere, and, here, we expand its documented range within northeastern Ireland and England. Established populations occur within two inlets in the border counties, Carlingford Lough (Counties Louth and Down) and Dundrum Bay (County Down), but G. vermiculophylla is absent from open coasts between these sites. Repeated surveys in Dundrum Bay showed variable abundances, with an increase in biomass between 2013 and 2016. Three populations were discovered in England, where this species had not previously been identified: Christchurch Harbour (Dorset), Brownsea Island in Poole Harbour (Dorset), and Kingsbridge Estuary (Devon). The Irish and English thalli belong to the most common, invasive cox1 haplotype 6. Using a combination of morphological observations and 10 microsatellite loci, we found that the population at Carlingford Lough included both reproductive haploid gametophytes and diploid tetrasporophytes and genetic signatures of sexual reproduction, but the populations at Christchurch and Brownsea displayed signatures of partial clonality. Genetic diversity was higher along the south coast of England as compared to the Irish population, consistent with patterns of diversity previously described for the European coasts. Finally, we also note the occurrence of a putative G. vermiculophylla population in Wales at Porthmadog, Gwynedd. As the sites in which we have now documented G. vermiculophylla in the British Isles also host shellfish aquaculture activities, our study is further evidence for the role of aquaculture in the spread of invasive species.