European rodent on the edge: status and distribution of the Vojvodina blind mole rat

Recent research of blind mole rats of the species complex Nannospalax (superspecies leucodon) identified a small and fragmented population of these rodents on both sides of the Hungarian-Serbian border. Cytogenetic investigations proved that this population karyologically identical with the Vojvodina blind mole rat described earlier as Nannospalax (leucodon) montanosyrmiensis. Based on cytochrome b gene sequences obtained from three specimens originating from separate locations, these blind mole rats form a discrete phylogenetic clade which, with a difference of about 10%, is well separated from other blind mole rat taxa inhabiting the Carpathian Basin. The taxon has only two extant populations that are 150 km apart from each other. The combined occupied area is estimated to be less than 10 km(2), and the total estimated number of individuals is less than 300. These two remaining populations are heavily fragmented and under imminent threat by the establishment of tree plantations, small-scale and agro-industrial farms and land development. The situation is further aggravated by the fact that 80% of the individuals inhabit unprotected areas. A study of the landscape history of the wider area surrounding one of the populations - based on military maps spanning over the last 200 years - has shown a drastic decrease in the extent and quality of potential habitats. Based on our present knowledge, the Vojvodina blind mole rat is one of the most seriously threatened, rarest mammal in Europe, the remaining population of which can be wiped out within years unless immediate conservation action is taken. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/2193-1801-2-2) contains supplementary material, which is available to authorized users

Gut microbiomes of sympatric Amazonian wood-eating catfishes (Loricariidae) reflect host identity and little role in wood digestion

© 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. Neotropical wood-eating catfishes (family Loricariidae) can occur in diverse assemblages with multiple genera and species feeding on the same woody detritus. As such, they present an intriguing system in which to examine the influence of host species identity on the vertebrate gut microbiome as well as to determine the potential role of gut bacteria in wood digestion. We characterized the gut microbiome of two co-occurring catfish genera and four species: Panaqolus albomaculatus, Panaqolus gnomus, Panaqolus nocturnus, and Panaque bathyphilus, as well as that of submerged wood on which they feed. The gut bacterial community did not significantly vary across three gut regions (proximal, mid, distal) for any catfish species, although interspecific variation in the gut microbiome was significant, with magnitude of interspecific difference generally reflecting host phylogenetic proximity. Further, the gut microbiome of each species was significantly different to that present on the submerged wood. Inferring the genomic potential of the gut microbiome revealed that the majority of wood digesting pathways were at best equivalent to and more often depleted or nonexistent within the catfish gut compared to the submerged wood, suggesting a minimal role for the gut microbiome in wood digestion. Rather, these fishes are more likely reliant on fiber degradation performed by microbes in the environment, with their gut microbiome determined more by host identity and phylogenetic history

Effects of water potential on spore germination and viability of Fusarium species

Germination of macroconidia and/or microconidia of 24 strains of Fusarium solani, F. chlamydosporum, F. culmorum, F. equiseti, F. verticillioides, F. sambucinum, F. oxysporum and F. proliferatum isolated from fluvial channels and sea beds of the south-eastern coast of Spain, and three control strains (F. oxysporum isolated from affected cultures) was studied in distilled water in response to a range of water potentials adjusted with NaCI. (0, -13.79, -41.79, -70.37, -99.56 and -144.54 bars). The vialibility (UFC/ml) of suspension was also tested in three time periods (0,24 and 48h). Conidia always germinated in distilled water. The pattern of conidial germination obseved of F. verticillioides, F. oxysporum, F. proliferatum, F. chlamydosporum and F. culmorum was similar. A great diminution of spore germination was found in -13.79 bars solutions. Spore germination percentage for F. solani isolates was maximal at 48 h. and -13.79 bars with 21.33% spore germination, 16% higher than germination in distilled water. F. equiseti shows the maximum germination percentage in -144.54 bars solution in 24 h time with 12.36% germination. These results did not agree with those obtained in the viability test where maximum germination was found in distilled water. The viability analysis showed the great capacity of F. verticilloides strains to form viable colonies, even in such extreme conditions as -144,54 bars after 24 h F. proliferatum colony formation was prevented in the range of -70.37 bars. These results show the clear affectation of water potential to conidia germination of Fusaria. The ability of certain species of Fusarium to develop a saprophytic life in the salt water of the Mediterraneam Sea could be certain. Successful germination, even under high salty media conditions, suggests taht Fusarium spp. could have a competitive advantage over other soil fungi in crops irrigated with saline water. In the specific case of F. solani, water potential of -13.79 bars affected germination positively. It could indicate that F. solani has an special physiological mechanism of survival in low water potential environments

Radiative-capture cross sections for the La139(n,γ) reaction using thermal neutrons and structural properties of La140

A set of prompt partial γ-ray production cross sections from thermal neutron capture were measured for the 139La (n,γ) reaction using a guided beam of subthermal (thermal and cold) neutrons incident on a nat La2O3 target at the Prompt Gamma Activation Analysis facility of the Budapest Research Reactor. Absolute 140La cross sections were determined relative to the well-known comparator 35Cl(n,γ) cross sections from the irradiation of a stoichiometric nat LaCl3 sample. The total cross section for radiative thermal neutron capture on 139La from the sum of experimentally measured cross sections observed to directly feed the 140 La ground state was determined to be σ0 = 8.58(50) b. To assess completeness of the decay scheme and as a consistency check, the measured cross sections for transitions feeding the ground state from levels below a critical energy of Ec = 285 keV were combined with a modeled contribution accounting for ground-state feeding from the quasi continuum to arrive at a total cross section of σ0 = 9.36(74) b. In addition, a neutron-separation energy of Sn = 5161.001(21) keV was determined from a least-squares fit of the measured primary γ-ray energies to the low-lying levels of the 140La decay scheme. Furthermore, several nuclear structure improvements are proposed for the decay scheme. The measured cross-section and separation-energy results are comparable to earlier measurements of these quantities