Morphological and chemical analysis of male scent organs in the butterfly genus Pyrgus (Lepidoptera: Hesperiidae)

Chemical communication in the family Hesperiidae (Lepidoptera) is practically unstudied, even though this group includes approximately 4,000 species and represents a fifth of the world's butterfly fauna. We present the first comparative morphological and chemical analysis of scent organs for nine species in the genus Pyrgus, the most species-rich hesperiid genus in the Palearctic region. Our results show that the morphology of the two main male scent organs - the costal fold and the tibial tufts - does not differ between species. The chemical analyses detected a total of 125 different compounds exclusively present in these organs. We document great interspecific differences and much narrower intraspecific variability in the chemical profiles. The dynamics of chemical versus genetic distances indicate two different phases: a faster (but more variable) initial chemical divergence at lower genetic divergences (probably related to speciation) and a slower but more constant differentiation (drift). As a result most species can be identified based on their chemical profiles, except for a closely related species pair (P. malvae/P. malvoides) for which hybridisation is common in the contact zone. Our results suggest that the Hesperiidae is a group with great potential for the study of chemical communication that deserves further attention. © 2014 Gesellschaft für Biologische Systematik.Funding for this research was provided by Universitat Autònoma de Barcelona (project EME2007-33 to J.L.H.-R., R.B. and R.V.) and by the Spanish Ministerio de Ciencia e Innovación (project CGL2010-21226/BOS to J.L.H.-R. and R.V. and project CGL2004-04680-c10-08/BOS to M.L.M.).Peer Reviewe

Genomics of extreme ecological specialists: multiple convergent evolution but no genetic divergence between ecotypes of Maculinea alcon butterflies.

Biotic interactions are often acknowledged as catalysers of genetic divergence and eventual explanation of processes driving species richness. We address the question, whether extreme ecological specialization is always associated with lineage sorting, by analysing polymorphisms in morphologically similar ecotypes of the myrmecophilous butterfly Maculinea alcon. The ecotypes occur in either hygric or xeric habitats, use different larval host plants and ant species, but no significant distinctive molecular traits have been revealed so far. We apply genome-wide RAD-sequencing to specimens originating from both habitats across Europe in order to get a view of the potential evolutionary processes at work. Our results confirm that genetic variation is mainly structured geographically but not ecologically - specimens from close localities are more related to each other than populations of each ecotype from distant localities. However, we found two loci for which the association with xeric versus hygric habitats is supported by segregating alleles, suggesting convergent evolution of habitat preference. Thus, ecological divergence between the forms probably does not represent an early stage of speciation, but may result from independent recurring adaptations involving few genes. We discuss the implications of these results for conservation and suggest preserving biotic interactions and main genetic clusters

Unrelated Helpers in a Primitively Eusocial Wasp: Is Helping Tailored Towards Direct Fitness?

The paper wasp Polistes dominulus is unique among the social insects in that nearly one-third of co-foundresses are completely unrelated to the dominant individual whose offspring they help to rear and yet reproductive skew is high. These unrelated subordinates stand to gain direct fitness through nest inheritance, raising the question of whether their behaviour is adaptively tailored towards maximizing inheritance prospects. Unusually, in this species, a wealth of theory and empirical data allows us to predict how unrelated subordinates should behave. Based on these predictions, here we compare helping in subordinates that are unrelated or related to the dominant wasp across an extensive range of field-based behavioural contexts. We find no differences in foraging effort, defense behaviour, aggression or inheritance rank between unrelated helpers and their related counterparts. Our study provides no evidence, across a number of behavioural scenarios, that the behaviour of unrelated subordinates is adaptively modified to promote direct fitness interests

The decline of the charismatic Parnassius mnemosyne (L.) (Lepidoptera: Papilionidae) in a central italy national park: A call for urgent actions

Here we report the strong decline of a population of the endangered species Parnassius mnemosyne (Linnaeus, 1758) (Lepidoptera: Papilionidae) in the National Park of Foreste Casentinesi, Monte Falterona and Campigna (Italy). We compared historical presence data (before 1969) with current data from two years of monitoring (2018–2019) and provided evidence of a drastic reduction in the number of sites inhabited by the species. A preliminary assessment suggested that the population of P. mmemosyne occurring in the Park is limited to a few individuals. We argue that the population of this iconic and charismatic butterfly is at the verge of extinction in this National Park, probably because of a combination of habitat loss (i.e. decrease in size and number of areas of open grassland on the mountain belt) and climatic changes. Being one of the few populations of P. mnemosyne in the Northern Apennines, the implementation of protection measures is a high conservation priority. Several other butterfly species on the Italian mountains that are facing the same survival challenges would also benefit from the establishment of conservation actions aimed at improving habitat quality for P. mnemosyne. Present article is meant to call for action researchers, stakeholders, and especially decision-makers in order to increase the efforts to upturn the evident decline in abundance of this population