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Ecological Niche Modelling output and input.

[EN] Although both positive (expansion of thermophilous species) and negative effects (retraction of cold-adapted species) have been attributed to global warming, range shifts may be constrained by the ecological traits of species. This can be especially true for highly specialised organisms like the Spanish Greenish Black-tip (Euchloe bazae), an Iberian endemic specialist of semiarid steppes with a debated taxonomic and conservation status. Here, we first seek to clarify the taxonomic status of this butterfly and its populations by using multilocus phylogenetic inference. Then, we update its distribution range and employ ecological niche modelling, combined with other sources of data, to re-evaluate its conservation status. Our results confirm E. bazae as a well-differentiated species with one of the most restricted distribution ranges among the European butterflies. We demonstrate that its two disjunct populations, regarded as subspecies, are genetically differentiated and should be treated as independent management units. Climate models under two future emission scenarios suggest an increase of the area climatically suitable. However, the suitability of the areas currently occupied is estimated to decrease, meaning that rapid range shifts could be required for the survival of the species. Given the presumably low dispersal capabilities of E. bazae, its current restricted distribution, high degree of population fragmentation (divided in two distant populations), low intrapopulation genetic variability, decline in extension and abundance, low densities, high yearly fluctuations, and numerous threats to its habitat, we consider that their populations are extremely fragile and we propose to consider it `Endangered¿ [EN B1ab(i,ii,iii,iv); B2ab(i,ii,iii,iv)]., [CA] Tot i que s’han atribuït tant efectes positius (expansió d’espècies termòfiles) com negatius (contracció d’espècies adaptades al fred) a l’escalfament global, canvis en les distribucions poden estar condicionats pels trets ecològics de les espècies. Això pot ser especialment cert per a organismes altament especialitzats com la grogueta del desert (Euchloe bazae), un endemisme ibèric especialista d’estepes semiàrides amb un estatus taxonòmic i de conservació debatut. En aquest estudi, primer cerquem esclarir l’estatus taxonòmic d’aquesta papallona ide les seves poblacions mitjançant la inferència filogenètica multilocus. També actualitzem la seva distribució i fem servir la modelització de nínxols ecològics com-binada amb altres dades per reavaluar el seu estatus de conservació. Els nostres resultats confirmen que E. bazae és una espècie ben diferenciada i amb una de les distribucions més restringides entre les papallones europees. Demostrem que els seus dos nuclis de població, cadascun considerat una sub-espècie, són diferents genèticament i s’han de tractar com a unitats de gestió independents. Els models climàtics elaborats amb dos escenaris d’emissions futurs suggereixen un augment de l’àrea climàticament adient. No obstant això, s’estima que la idoneïtat de l’àrea actualment ocupada disminuirà, el que podria requerir canvis ràpids en la seva distribució per garantir-ne la supervivència. Tenint en compte que E. bazae disposaria d’una capacitat de dispersió baixa, la distribució actual reduïda, l’alt grau de fragmentació (dividida en dues poblacions llunyanes), la baixa variabilitat genètica intra poblacional, la disminució de l’extensió i l’abundància, les baixes densitats, les elevades fluctuacions anuals i les nombroses amenaces al seu hàbitat, considerem que les poblacions d’aquesta papallona són extremament fràgils i proposem considerar-la “En perill”

We estimated the potential impact of Global Warming on the species richness of Iberian butterflies. First, we determined the grid size that maximized the balance between geographic resolution, area coverage and environmental representativeness. Contemporary richness was modelled in several alternative ways that differed in how sampling effort was controlled for, and in whether the non-climatic variables (physiography, lithology, position) were incorporated. The results were extrapolated to four WorldClim scenarios. Richness loss is to be expected for at least 70% of the area, with forecasts from the combined models being only slightly more optimistic than those from the purely climatic ones. Overall, the most intense losses are predicted for areas of highest contemporary species richness, while the potential slightly positive or nearly neutral changes would most often concentrate in cells of low to moderate present richness. The environmental determinants of richness might not be uniform across the geographical range of sampling effort, suggesting the need of additional data from the least intensively surveyed areas.

Evaluating data quality and inventory completeness must be a preliminary step inany biodiversity research, particularly in the case of insects and high biodiversityareas. Yet, this step is often neglected or, at best, assessed only for one insectgroup, and the degree of congruence of sampling effort ffor different insect groupsremains unexplored. We assess the congruence in the spatial distribution of sampling effort for fiveinsect groups (butterflies, caddisflies, dung beetles, moths, and aquatic beetles) inthe Iberian Peninsula. We identify well-surveyed areas for each taxonomic groupand examine the degree to which the patterns of sampling effort can be explainedby a set of variables related to environmental conditions and accessibility. Irrespective of the general lack of reliable inventories, we found a general but lowcongruence in the completeness patterns of the different taxa. This suggests thatthere is not a common geographical pattern in survey effort and that idiosyncraticand contingent factors (mainly the proximity to the workplaces of entomologists)are differentially affecting each group. After many decades of taxonomic and faunistic work, distributional databases ofIberian insects are still in a very preliminary stage, thus limiting our capacity toobtain reliable answers to basic and applied questions. We recommend carrying out long-term, standardised and well-designed entomolog-ical surveys able to generate a reliable image of the distribution of different insect groups. This will allow us to estimate accurately insect trends and better under-stand the full extent of global biodiversity loss.

1. Indices of environmental associations such as the Community Temperature Index (CTI) and Community Precipitation Index (CPI) can be derived from occurrence data to extend the geographic scope or time frame of evidence for responses of insect diversity to global change., 2. We tested whether occurrence records from 1901 to 2016 from the Iberian Peninsula could shed light on butterfly community responses to changes over space and time in the climate; and whether local climatic variation caused by topographic heterogeneity could buffer communities against the effects of climate change., 3. CTI and CPI were closely related to variation in temperature and precipitation across 115 well-sampled 10 km grid squares. However, whereas temperature and precipitation changed systematically from 1901–1979 to 1980–2016, and these changes were positively related to changes in CTI and CPI, community climatic associations did not change significantly over time. Butterfly communities became more associated with closed vegetation, suggesting that land cover changes overshadowed the effects of climate change., 4. Local (1 km) climatic variation generally exceeded change over time at 10 km resolution, and heterogeneity in elevation slowed rates of warming. In turn, spatial variation in climatic conditions dampened butterfly community responses to heating and drying., 5. Occurrence data are limited by their spatial resolution but can inform understanding of insect community responses to global change for regions lacking long-term monitoring data. Our results suggest that local climatic variation accompanying topographic heterogeneity can shield regional butterfly faunas from the impacts of climate change.

Reproductive character displacement occurs when competition for successful breeding imposes a divergent selection on the interacting species, causing a divergence of reproductive traits. Here, we show that a disputed butterfly taxon is actually a case of male wing colour shift, apparently produced by reproductive character displacement. Using double digest restriction-site associated DNA sequencing and mitochondrial DNA sequencing we studied four butterfly taxa of the subgenus Cupido (Lepidoptera: Lycaenidae): Cupido minimus and the taxon carswelli, both characterized by brown males and females, plus C. lorquinii and C. osiris, both with blue males and brown females. Unexpectedly, taxa carswelli and C. lorquinii were close to indistinguishable based on our genomic and mitochondrial data, despite displaying strikingly different male coloration. In addition, we report and analysed a brown male within the C. lorquinii range, which demonstrates that the brown morph occurs at very low frequency in C. lorquinii. Such evidence strongly suggests that carswelli is conspecific with C. lorquinii and represents populations with a fixed male brown colour morph. Considering that these brown populations occur in sympatry with or very close to the blue C. osiris, and that the blue C. lorquinii populations never do, we propose that the taxon carswelli could have lost the blue colour due to reproductive character displacement with C. osiris. Since male colour is important for conspecific recognition during courtship, we hypothesize that the observed colour shift may eventually trigger incipient speciation between blue and brown populations. Male colour seems to be an evolutionarily labile character in the Polyommatinae, and the mechanism described here might be at work in the wide diversification of this subfamily of butterflies.