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Dryocosmus kuriphilus Yasumatsu, 1951 (Hymenoptera, Cynipidae) or Asian chestnut gall wasp, has been one of the most important pest insects on the chestnut tree (Castanea sativa) in the last 20 years in Europe. In Romania, it was observed since 2015 in the western part of the country, but the population was kept under control without a negative impact. After almost four years, a new presence of this species in Northeastern Romania was discovered in the most important area for Castanea sativa, The Chestnut Forest from Baia Mare which is a Natura 2000 protected area (Arboretele de castan comestibil de la Baia Mare, ROSCI0003) The distribution of the pest in this area is clustered (Moran's Index = 0.311) with a preference on eastern and western exposure and higher temperatures. The colonization in this area can be explained by the introduction of infested chestnut trees without the quarantine treatment. This study aims to present the distribution of D. kuriphilus, the level of infestation, and climatic preferences for suitable management of a future biological control program in Romania [ABSTRACT FROM AUTHOR]

Activity patterns in animals are often species-specific, and can be generally categorized as diurnal, crepuscular, or nocturnal. Understanding these patterns provides insight into ecological adaptations and behaviors. The common grass snake (Natrix natrix), one of the most common and widespread European snake species, is traditionally considered diurnal, with scarce evidence of its crepuscular and nocturnal activity. We aimed to document the distribution, environmental conditions, and potential phenotype associations of nighttime activity in N. natrix. We used citizen science data from iNaturalist (1992-2022), Observation.org (2012-2022), together with personal field observations (2010-2023) to collect 127 crepuscular and nocturnal activity records. Most observations occurred between May and August, coinciding with the peak activity period of grass snakes across their distribution range. Statistical analyses revealed no significant difference in mean daily temperatures between crepuscular and nocturnal observations. However, striped individuals displayed nocturnal activity at higher temperatures, consistent with their distribution in warmer regions, but failed to register any difference when tested on a geographic subsample, that accounted for sympatry of the phenotypes. Surprisingly, we found no significant impact of moon presence or moonlight on nighttime activity or age class, contrary to expectations based on other snake species' responses. While our study reveals that nocturnal activity in the common grass snake is geographically widespread, further research is warranted to understand its drivers and ecological implications. This study highlights the value of citizen science platforms for biological and ecological research, offering unparalleled spatial and temporal coverage by their users. In conclusion, our work extends the knowledge of nocturnal behavior in N. natrix and underlines the critical role of citizen science in discovering behavioral aspects of common and widespread species. [ABSTRACT FROM AUTHOR]

ABSTRACT Background and Aim Location Taxon Results Main Conclusions Colour polymorphic populations constitute excellent model systems for testing ecological and evolutionary hypotheses, as alternate colourations are associated with differences in various biological, behavioural and life‐history traits. Melanism is the most common and most obvious form of polymorphism. In reptiles in general (and snakes in particular), thermal melanism has been a popular hypothesis used to explain the appearance of black individuals. It suggests that a trade‐off exists between superior thermoregulation and reduced protection through the loss of crypsis. Surprisingly, despite the growing body of literature available, to date, there are only two qualitative reviews on the evolutionary significance of melanism in reptiles and no quantitative synthesis. We conducted the first systematic review and meta‐analysis summarising the current knowledge on melanism in polymorphic terrestrial snakes and synthesised the evidence for an adaptive advantage of the melanistic morph.Northern Hemisphere.Polymorphic terrestrial snakes.Mean prevalence of melanism is 31% with no significant differences between species. Annual precipitation was a significant moderator of melanism prevalence. Our results revealed no significant differences in odds ratios of melanism between sexes or in mean body size.Environmental plasticity can be considered the primary cause of melanism, possibly as a result of seasonal climatic variations, a result corroborated by the formal meta‐analysis conducted. Conclusions from the meta‐analysis are that melanism in snakes follows Gloger's rule, as is the case in birds and mammals, and as opposed to the thermal melanism hypothesis. Further, our findings do not lend support for other predictions from the thermal melanism hypothesis, such as skewed frequency of melanistics in favour of males or females, or larger body sizes in black individuals. Our results hold implications for the future diversity of animal populations, as climate change is predicted to decrease the degree of colour variation. [ABSTRACT FROM AUTHOR]

Animal colorations represent adaptations to different biotic or abiotic environmental factors and play crucial roles in predator avoidance, communication and sexual selection. In ectothermic animals, coloration also plays important roles in thermoregulation. The thermal melanism hypothesis states that darker individuals belonging to ectothermic species will be superior to lighter individuals with regards to thermoregulation. However, individuals that are completely or almost completely black (melanistic) often lose the cryptic or aposematic signaling function of the patterned coloration, and may thus be more vulnerable to predation. While these statements appear to be valid for some species and populations, there are cases with peculiar characteristics, such as the lowland southern clades of the Vipera berus complex, where melanism is either common in polymorphic populations, or where entire populations comprise only melanistic individuals. We aimed to experimentally test weather the type of coloration is relevant for predator-prey interactions (i.e. vipers being the prey) in a polymorphic population of Vipera nikolskii from North-Eastern Romania. Employing methods proven successful in previous studies, we used 90 viper replicas made of plasticine, that we installed in the field, in a habitat known to be inhabited by vipers. 50% of the replicas were patterned (typical zigzag pattern) while 50% were completely black (resembling melanistic vipers). 50% of all models were placed on a white sheet of cardboard, in order to eliminate the role of crypsis from any of the colorations. Replicas were inspected for predation events every 48 hours, and were retrieved after a total of 10 days in the field. Our preliminary results indicate a significantly higher predation rate on melanistic individuals, confirming previous studies. We thus show that the high frequency of melanism in these populations is not a result of relaxed predation upon them. Future work will also be conducted in a purely melanistic population. [ABSTRACT FROM AUTHOR]

Animal colorations represent adaptations to different biotic or abiotic environmental factors and play crucial roles in predator avoidance (via crypsis, aposematism, or mimicry), inter -- and intraspecific communication and sexual selection. In ectothermic animals, coloration may also be important for thermoregulation. Colour polymorphism (i.e. the occurrence of two or more phenotypic morphs in the same population) is present along numerous animal lineages, and melanism is probably the most studied type. In several Eurasian viper species of the genus Vipera, populations greatly vary with regards to the frequency of melanistic individuals, and the maintenance of polymorphism have been attributed to either adaptive or non-adaptive processes. Current theory would predict that melanistic vipers should be more frequent in colder environments (normally higher latitudes or altitudes), and this is mostly confirmed for the Asp Viper (Vipera aspis). Here we tested the hypothesis that differential habitat use and activity patterns could explain the maintenance of colour polymorphism in a viper population from warmer environment. In accordance with the thermal melanism hypothesis, we would expect melanistic vipers to predominantly use less open habitats and/or be more active at cooler temperatures, as they should be thermoregulatory superior to patterned (zigzag) individuals. Overall, our results show a weak support for the differential habitat use hypothesis, with only one habitat characteristic (microhabitat exposure) being significantly associated with morph, but only for females (χ²=13.475, df = 6, p = 0.036)). However, observational data does suggest that activity patterns do differ, with melanistic vipers being especially active during overcast and rainy periods, although no differences were observed between basking site temperatures. Other adaptive as well as non-adaptive hypotheses require testing before we can gain a deeper understanding of maintenance of melanism in vipers from warmer environments. [ABSTRACT FROM AUTHOR]

Reptiles are amongst the vertebrates most threatened with extinction. Many snake species are affected by climatic changes as a result of their physiological characteristics and by the loss of habitat. In Central and Eastern Europe, the conversion of lowland habitats like grasslands and meadows into arable land had a major impact on species linked to such habitats. One such species is the meadow viper (Vipera ursinii). In Romania two subspecies have been identified (V. u. rakosiensis and V. u. moldavica), both of them being classified in a high risk category for extinction in the IUCN Red List. The Moldavian meadow viper (V. u. moldavica) is the easternmost subspecies of the Vipera ursinii complex, and it is also the most threatened (CR -- critically endangered). Historically, it was recorded from Bulgaria, the Republic of Moldova, and five counties in eastern Romania, and for a long time it was only known to have survived in two counties from Romania: Iaşi in the north-east, and Tulcea (the Danube Delta). Here we update the current knowledge of the distribution and conservation status of the Moldavian meadow viper in Romania by presenting a remarkable new occurrence record from the Carpathian Bend area (Buzău county) and utilize species distribution modelling to identify new potentially suitable areas for the species. Finally, we ran phylogenetic analyses using mitochondrial and nuclear DNA markers sequenced from all currently known regions of occurrence, together with previously published sequences. A very low genetic variation was found for V. u. moldavica, suggesting a very recent dispersal and/ or fragmentation. [ABSTRACT FROM AUTHOR]

European reptiles are among the most threatened groups of animals. For most of them are protected, reptiles may act as umbrella and flagship species in certain areas. The Natura 2000 site "Sărăturile Jijia inferioară -- Prut" (ROSCI0222) is such an area that, despite its conservation status, is largely exposed to human activities and alterations. Thus, the aim of this study is to update the knowledge on local reptiles. Therefore, we carried out field surveys in the site perimeter, from April to August, 2018 and from March to July, 2019. We identified five reptile species (Emys orbicularis, Lacerta agilis, Lacerta viridis, Coronella austriaca, and Natrix natrix) that are typical for the major relief forms of the area. Four of the identified species are strictly protected according to European and national regulations, whereas the standard data form of the area lists only one species. Hence, the management plan of the site should consider all the strictly protected species as the standard data form fails to reflect the actual richness of the reptile assemblages. [ABSTRACT FROM AUTHOR]