Semiochemical baited traps of lepidopteran pests of economic importance can deliver reliable data also on wide range of non-target species: case study in the Hajdúság Region of East Pannonian Lowland (East Hungary)

Lepidopteran assemblages were studied at 16 sampling sites in the Hajdúság Region between 2013 and 2020. Although studies targeted development of synthetic phenylacetaldehyde-based and semi-synthetic isoamyl alcohol-based baits for pest monitoring, traps caught 179 species belonging to the Sphingidae, Thyatiridae, Geometridae, Erebidae and Noctuidae families. Most species were pests or widely distributed generalists, but there were also many rare habitat specialists, for example, silvicol species, whose appearance was unexpected in the recently less forested region. The specificity of the two bait types tested differed notably both on family and subfamily levels. Semi-synthetic baits performed better and attracted a wide range of noctuids belonging mainly to the Xyleninae and Noctuinae subfamilies, while synthetic phenylacetaldehyde-based lures showed specificity to Plusiinae subfamilies with lower number of sampled species. Our data fill a gap of knowledge since the fauna studied formerly was nearly unknown and brings attention to the alternative use of volatile traps of agricultural pests in faunistical studies.

Ormyrus labotus Walker (Hymenoptera: Ormyridae): another generalist that should not be a generalist is not a generalist

Several recent reappraisals of supposed generalist parasite species have revealed hidden complexes of species, each with considerably narrower host ranges. Parasitic wasps that attack gall-forming insects on plants have life history strategies that are thought to promote specialization, and though many species are indeed highly specialized, others have been described as generalist parasites. Ormyrus labotus Walker (Hymenoptera: Ormyridae) is one such apparent generalist, with rearing records spanning more than 65 host galls associated with a diverse set of oak tree species and plant tissues. We pair a molecular approach with morphology, host ecology, and phenological data from across a wide geographic sample to test the hypothesis that this supposed generalist is actually a complex of several more specialized species, though we identify no single unifying axis of specialization. We find 16-18 putative species within the morphological species O. labotus, each reared from only 1-6 host gall types. We also find cryptic habitat specialists within two other named Ormyrus species. Our study suggests that caution should be applied when considering host ranges of parasitic insects described solely by morphological traits, particularly given their importance as biocontrol organisms and their role in biodiversity and evolutionary studies.

Combined impacts of climate and land use change and the future of Neotropical bat biodiversity

Forecasting the effects of global change on biodiversity is necessary to anticipate the threats operating at different scales in space and time. Climate change may create unsuitable environmental conditions, forcing species to move to persist. However, land-use changes create barriers that limit the access of some species to future available habitats. Here, we project the impacts of climate and land-use change on 228 Neotropical bat species by forecasting changes in environmental suitability, while accounting for the effect of habitat type specialization and simulating dispersal across suitable patches. We also identify the most vulnerable ecoregions and those that may offer future stable refugia. We further investigate potential functional changes by analysing the response of different trophic guilds. We found that the range contraction of habitat specialists, especially frugivores, was more frequent and stronger under all simulated scenarios. Projected changes differ markedly across ecoregions. While the Amazon region is likely to undergo high turnover rates in bat composition, the Andean grassland, Cerrado and Chaco might experience the greatest losses. The expansion of habitat generalists, which forage in open areas and commonly establish large colonies in manmade structures, coupled with the range contraction of habitat specialists is projected to homogenize bat communities across the Neotropics. Overall, dispersal will likely be the key for the future of Neotropical bat diversity. Therefore, safeguarding the refugia highlighted here, by expanding and connecting the existing network of protected areas, for example, may allow species to move in response to global change.

Disentangling niche theory and beta diversity change

Beta diversity describes the differences in species composition among communities. Changes in beta diversity over time are thought to be due to selection based on species' niche characteristics. For example, theory predicts that selection that favours habitat specialists will increase beta diversity. In practice, ecologists struggle to predict how beta diversity changes. To remedy this problem, we propose a novel solution that formally measures selection's effects on beta diversity. Using the Price equation, we show how change in beta diversity over time can be partitioned into fundamental mechanisms including selection among species, variable selection among communities, drift, and immigration. A key finding of our approach is that a species' short-term impact on beta diversity cannot be predicted using information on its long-term environmental requirements (i.e. its niche). We illustrate how our approach can be used to partition causes of diversity change in a montane tropical forest before and after an intense hurricane. Previous work in this system highlighted the resistance of habitat specialists and the recruitment of light-demanding species but was unable to quantify the importance of these effects on beta diversity. Using our approach, we show that changes in beta diversity were consistent with ecological drift. We use these results to highlight the opportunities presented by a synthesis of beta diversity and formal models of selection.