Diversity and community structure of Ephemeroptera in freshwater stream of Megamalai hills, Tamil Nadu, India

In the study on the diversity and community structure of Ephemeroptera in the freshwater stream of Chinnasuruli falls on Megamalai hills, a total of 523 specimens belonging to thirteen genera and five families were collected in six month periods. Of the five families, Teloganodidae and Leptophlebiidae exhibited high diversity and Caenidae showed low diversity. Choroterpes alagarensis (Leptophlebiidae) is the most dominant species. Diversity indices such as Shannon and Simpson indices showed that diversity was maximum in November and December and it was minimum in August and January. Canonical Correspondence Analysis revealed that rainfall, water flow, turbidity, and air temperature were the major stressors in affecting the Ephemeropteran community structure.

Genome of a novel Sediminibacterium discovered in association with two species of freshwater stream Cyanobacteria in Southern California

ABSTRACTHere we report the discovery of a novel Sediminibacterium sequenced from laboratory cultures of freshwater stream cyanobacteria from sites in Southern California, grown in BG11 media.

Aquatisphaeria thailandica gen. et sp. nov. (Tetraplosphaeriaceae, Pleosporales) from freshwater habitat in Thailand

A novel hyphomycetous genus collected from submerged wood in a freshwater stream in Thailand is introduced. The fungus is similar to Tetraplosphaeriaceae species in having subglobose conidial body and elongated setose appendages arising from conidial body. However, its unique combination of macronematous conidiophores and conidia composed with several columns of cells differs it from other genera in Tetraplosphaeriaceae. The phylogenetic analysis based on a combined LSU, ITS and SSU sequence data indicated that our two strains formed a distinct lineage in the family and they cannot be assigned to any existing genera. Therefore, we introduce a new genus Aquatisphaeria to accommodate the new taxa with A. thailandica as the type species. The detailed description, illustration and comparison with related taxa are provided.

ECOLOGIA COMPORTAMENTAL EVOLUTIVA APLICADA A PEIXES DE RIACHO

Direct field observation constitutes an important source of information on life history and behavior of stream fish. Unfortunately, information gathered from direct field observations are often limited and thus may fail to provide robust testing for the causation of biological phenomena. Here, we bring concepts that form the theoretical foundation necessary for raising hypotheses in Evolutionary Behavioral Ecology,a study area directly derived from natural history and ethology that directly incorporates evolutionary processes and the adaptative value of behavioral patterns observed. This perspective allows the analysis of the evolutionary context and the adaptive value of observed behavioral patterns, and serves as the basis for new hypotheses that can be applied to many groups of organisms. Using this framework, field observations and experiments encompassing freshwater stream fish have subsidized many theories on the evolution of behavioral and morphological traits that are widespread debated by scientific community. After presenting the main key concepts, we bring some examples of research programs with freshwater fish that culminated in the formulation of important theories and where scientists took advantage of the opportunities provided by stream fish to conduct observations, samplings and controlled experiments both in the field and in captivity. We also describe our own research program, which uses an Amazonian freshwater stream fish (Crenuchus spilurus) as a model organism. By doing so, we advocate for the use of several methods and analyses for the study of Evolutionary Behavioral Ecology of freshwater stream fish.

Ecological Risks of Heavy Metals and Microbiome Taxonomic Profile of a Freshwater Stream Receiving Wastewater of Textile Industry

Textile wastewater (TWW) contains toxic metals that are inimical to microbiome, aesthetic quality, and the health of the receiving freshwater. TWW-impacted freshwater (L2) was assessed for metals eco-toxicity and the consequent impact on microbiome taxonomic profile (MTP) compared to a pristine environment (L1). The conductivity (1750 μS/cm), chemical oxygen demand (2,110 mg/L), biochemical oxygen demand (850 mg/L), and salinity (5,250 mg/L) of L2 were far above the permissible limits. Mercury posed very high ecological risks in the water column of L2 as lead, arsenic, and copper exerted high risk in the sediment. The MTP of L2 revealed the dominance of Euryarchaeota (48.6%) and Bathyarchaeota (45.9%) among the Archaea. The relative abundances of Proteobacteria and Bacteroidetes increased from 38.3 to 2.0%, respectively, in the L1 ecosystem to 42.1 and 12.9%, correspondingly, in L2. Unclassified Eukarya_uc_p (50.4%) and Fungi_uc (16.0%) were key players among the fungi kingdom in L2. The impact of the TWW on the microbiome was evident with the extinction of 6,249, 32,272, and 10,029 species of archaea, bacteria, and fungi, respectively. Whereas, 35,157, 32,394, and 7,291 species of archaea, bacteria, and fungi, correspondingly, exclusively found in L2 were assumed to be invading resident communities that combined with dominant autochthonous strains in shaping the ecophysiology dynamics in TWW-impacted freshwater. While the sensitive microorganisms in L2 are suggested bio-indicators of TWW ecotoxicity, the emergent and dominant taxa are pivotal to natural attenuation processes in the contaminated ecosystem that could be adopted for biotechnological strategy in decommissioning the TWW-impacted freshwater.

Permianibacter fluminis sp. nov., isolated from a freshwater stream

A Gram-stain-negative, aerobic, non-motile and rod-shaped bacterium, designated as IMCC34836T, was isolated from a freshwater stream. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain IMCC34836T was most closely related to Permianibacter aggregans HW001T (of the family Pseudomonadaceae ) with 95.6 % sequence similarity and formed a robust clade with P. aggregans HW001T. The draft genome sequence of strain IMCC34836T was 4.4 Mbp in size with 59.1 mol% DNA G+C content. Average nucleotide identity and digital DNA–DNA hybridization values between strain IMCC34836T and P. aggregans HW001T were 71.2 and 22.0 %, respectively, indicating that the new strain represents a novel species. The strain contained iso-C15 : 0, summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 1 10-methyl) as the major fatty acids and harboured phosphatidylethanolamine, two unidentified aminophospholipids and three unidentified lipids as major polar lipids. The isoprenoid quinone detected in the strain was ubiquinone-8. Based on the phylogenetic and phenotypic characteristics, strain IMCC34836T is considered to represent a novel species of the genus Permianibacter , for which the name Permianibacter fluminis sp. nov. is proposed. The type strain is IMCC34836T (=KACC 21755T=NBRC 114416T).

Integrating Different Lines of Evidence to Establish a Novel Ascomycete Genus and Family (Anastomitrabeculia, Anastomitrabeculiaceae) in Pleosporales

A novel genus, Anastomitrabeculia, is introduced herein for a distinct species, Anastomitrabeculia didymospora, collected as a saprobe on dead bamboo culms from a freshwater stream in Thailand. Anastomitrabeculia is distinct in its trabeculate pseudoparaphyses and ascospores with longitudinally striate wall ornamentation. A new family, Anastomitrabeculiaceae, is introduced to accommodate Anastomitrabeculia. Anastomitrabeculiaceae forms an independent lineage basal to Halojulellaceae in Pleosporales and it is closely related to Neohendersoniaceae based on phylogenetic analyses of a combined LSU, SSU and TEF1α dataset. In addition, divergence time estimates provide further support for the establishment of Anastomitrabeculiaceae. The family diverged around 84 million years ago (MYA) during the Cretaceous period, which supports the establishment of the new family. The crown and stem age of Anastomitrabeculiaceae was also compared to morphologically similar pleosporalean families.