Sofia G. Seabra

Cicadas from Portugal: revised list of species with eco-ethological data (Hemiptera: Cicadidae)

The cicada fauna from Portugal is reviewed, as a result of a joint Portuguese-French project. Thirteen species are reported (Lyristes plebejus, Cicada orni, Cicada barbara lusitanica, Tibicina tomentosa, Tibicina quadrisignata, Tibicina garricola, Melampsalta varipes, Tympanistalna gastrica, Euryphara contentei, Tettigetta argentata, Tettigetta estrellae, Tettigetta josei, Tettigetta mariae), while five taxa which were previously referred to in the literature, have not been found (Tibicina corsica fairmairei, Tibicina haematodes, Tibicina nigronervosa, Cicadetta flaveola, Cicadivetta tibialis). Based on morphological and acoustic features, the following synonymies are established: Tettigetta argentata (Olivier, 1790) = Tettigetta atra (Gomez-Menor, 1957) n. syn. and Tettigetta estrellae Boulard, 1982 = Tettigetta septempulsata Boulard & Quartau, 1991 n. syn. Data on time of emergence, geographical distribution, habitat occupation and acoustic calling behaviour are given for each species.

Molecular phylogeny and DNA barcoding in the meadow-spittlebug Philaenus spumarius (Hemiptera, Cercopidae) and its related species

Philaenus spumarius, widely studied for its colour/pattern polymorphism, is a widespread species across the Holartic. The patterns of haplotype divergence at the mitochondrial gene cytochrome oxidase I (COI) found in this study suggest a postglacial western Europe (Iberian and Italian peninsulas to Britain) and a eastern (from Near East to Finland) south-to-north colonization. The haplotypes found in North America are most likely derived from the British haplotypes. The barcode fragment used here allowed the distinction of the species within genus Philaenus and questioned some taxonomic identifications of sequences present in Genbank.

Conflicting patterns of DNA barcoding and taxonomy in the cicada genus Tettigettalna from southern Europe (Hemiptera: Cicadidae)

DNA barcodes have great potential to assist in species identification, especially when high taxonomical expertise is required. We investigated the utility of the 5′ mitochondrial cytochrome c oxidase I (COI) region to discriminate between 13 European cicada species. These included all nine species currently recognized under the genus Tettigettalna, from which seven are endemic to the southern Iberian Peninsula. These cicadas have species‐specific male calling songs but are morphologically very similar. Mean COI divergence between congeners ranged from 0.4% to 10.6%, but this gene was proven insufficient to determine species limits within genus Tettigettalna because a barcoding gap was absent for several of its species, that is, the highest intraspecific distance exceeded the lowest interspecific distance. The genetic data conflicted with current taxonomic classification for T. argentata and T. mariae. Neighbour‐joining and Bayesian analyses revealed that T. argentata is geographically structured (clades North and South) and might constitute a species complex together with T. aneabi and T. mariae. The latter diverges very little from the southern clade of T. argentata and shares with it its most common haplotype. T. mariae is often in sympatry with T. argentata but it remains unclear whether introgression or incomplete lineage sorting may be responsible for the sharing of haplotypes. T. helianthemi and T. defauti also show high intraspecific variation that might signal hidden cryptic diversity. These taxonomic conflicts must be re‐evaluated with further studies using additional genes and extensive morphological and acoustic analyses.

Patterns of acoustic variation in Cicada barbara Stål (Hemiptera, Cicadoidea) from the Iberian Peninsula and Morocco

Field recordings of the calling song and of an amplitude modulated signal produced by males of Cicada barbara from North Africa and the Iberian Peninsula were analysed in order to assess the geographical acoustic variation and the potential usefulness of acoustic data in the discrimination of subspecies and populations. Sound recordings were digitized and the frequency and temporal properties of the calls of each cicada were analysed. In all regions studied, peak frequency, quartiles 25, 50 and 75% and syllable rate showed low coefficients of variation suggesting inherent static properties. All frequency variables were correlated with the latitude, decreasing from south to north. In addition, most acoustic variables of the calling song showed significant differences between regions, and PCA and DFA analyses supported a partitioning within this species between Iberian Peninsula+Ceuta and Morocco, corroborating mtDNA data on the same species. Therefore, the subspecific division of C. barbara into C. barbara barbara from Morocco and C. barbara lusitanica from Portugal, Spain and Ceuta finds support from the present acoustic analyses, a result which is also reinforced by molecular markers.

New mitochondrial and nuclear evidences support recent demographic expansion and an atypical phylogeographic pattern in the spittlebug Philaenus spumarius (Hemiptera, Aphrophoridae)

Philaenus spumarius is a widespread insect species in the Holarctic region. Here, by focusing on the mtDNA gene COI but also using the COII and Cyt b genes and the nuclear gene EF-1α, we tried to explain how and when its current biogeographic pattern evolved by providing time estimates of the main demographic and evolutionary events and investigating its colonization patterns in and out of Eurasia. Evidence of recent divergence and expansion events at less than 0.5 Ma ago indicate that climate fluctuations in the Mid-Late Pleistocene were important in shaping the current phylogeographic pattern of the species. Data support a first split and differentiation of P. spumarius into two main mitochondrial lineages: the “western”, in the Mediterranean region and the “eastern”, in Anatolia/Caucasus. It also supports a following differentiation of the “western” lineage into two sub-lineages: the “western-Mediterranean”, in Iberia and the “eastern-Mediterranean” in the Balkans. The recent pattern seems to result from postglacial range expansion from Iberia and Caucasus/Anatolia, thus not following one of the four common paradigms. Unexpected patterns of recent gene-flow events between Mediterranean peninsulas, a close relationship between Iberia and North Africa, as well as high levels of genetic diversity being maintained in northern Europe were found. The mitochondrial pattern does not exactly match to the nuclear pattern suggesting that the current biogeographic pattern of P. spumarius may be the result of both secondary admixture and incomplete lineage sorting. The hypothesis of recent colonization of North America from both western and northern Europe is corroborated by our data and probably resulted from accidental human translocations. A probable British origin for the populations of the Azores and New Zealand was revealed, however, for the Azores the distribution of populations in high altitude native forests is somewhat puzzling and may imply a natural colonization of the archipelago.

Keeping your options open: Maintenance of thermal plasticity during adaptation to a stable environment.

Phenotypic plasticity may allow species to cope with environmental variation. The study of thermal plasticity and its evolution helps understanding how populations respond to variation in temperature. In the context of climate change, it is essential to realize the impact of historical differences in the ability of populations to exhibit a plastic response to thermal variation and how it evolves during colonization of new environments. We have analyzed the real‐time evolution of thermal reaction norms of adult and juvenile traits in Drosophila subobscura populations from three locations of Europe in the laboratory. These populations were kept at a constant temperature of 18ºC, and were periodically assayed at three experimental temperatures (13ºC, 18ºC, and 23ºC). We found initial differentiation between populations in thermal plasticity as well as evolutionary convergence in the shape of reaction norms for some adult traits, but not for any of the juvenile traits. Contrary to theoretical expectations, an overall better performance of high latitude populations across temperatures in early generations was observed. Our study shows that the evolution of thermal plasticity is trait specific, and that a new stable environment did not limit the ability of populations to cope with environmental challenges.

Conus pennaceus: a phylogenetic analysis of the Mozambican molluscan complex

The genus Conus has over 500 species and is the most species-rich taxon of marine invertebrates. Based on mitochondrial DNA, this study focuses on the phylogenetics of Conus, particularly the pennaceus complex collected along the Mozambican coast. Phylogenetic trees based on both the 16S and the 12S ribosomal genes grossly revealed the same groupings: one that clustered the individuals from the north (Pemba, Nacala and Island of Mozambique), another that grouped the individuals from the central/southern coast (Pomene/Massinga and Inhambane) and a third that assembled the specimens from the central/southern islands (Bazaruto and Inhaca). The 16SrRNA-based trees further distinguished the northern group into a Nacala group and a Pemba+Island of Mozambique group. In all trees, C. p. bazarutensis and C. lohri collected on the central/southern islands grouped separately from the C. p. bazarutensis and C. lohri collected on the central/southern coast, suggesting a genetic similarity between these species. Likewise, C. praelatus revealed greater proximity to C. pennaceus from Pemba. Although different topologies were produced by each gene (low bootstrap support in some nodes), we support the hypothesis of a southward ancestral colonisation pattern, indicated by the 16SrRNA trees. The common ancestor would have shifted from planktonic to non-planktonic larval development and this weak vagility would have promoted the divergence between north and south specimens. Our results suggest that the separation of these groups might have been a relatively recent event, and part of the current morphological variability could be the outcome of phenotypic plasticity and/or ecological adaptation.

History, chance and selection during phenotypic and genomic experimental evolution: replaying the tape of life at different levels.

Ever since Darwin, understanding evolutionary processes and patterns have been major scientific quests. In the Origin of Species, Darwin explained both adaptation and diversity, and most of his arguments were based on indirect evidence, including comparative approaches. These findings led Darwin to defend that evolution in nature is extremely slow and gradual, hardly being directly observable at the scale of a human generation. Artificial selection, in contrast, was used by Darwin to illustrate the efficacy of natural selection (Darwin, 1859). During the last decades, evolution has been observed in real time. This opened new research possibilities and gave rise to Experimental Evolution, a rapidly expanding field that covers many topics and organisms (Garland and Rose, 2009; Kawecki et al., 2012). The joint power of experimental evolution and recently developed genome-wide tools may now lead us a step further in understanding real-time evolutionary dynamics of populations, both at phenotypic and genomic levels (Baldwin-Brown et al., 2014; Schlotterer et al., 2014). Our contribution to this special issue of Frontiers in Genetics focuses on the power of these approaches to assess the role of historical contingencies during adaptation to novel environments, a fundamental subject that has been neglected.

Isolation and characterization of fifteen polymorphic microsatellite loci for the citrus mealybug, Planococcus citri (Hemiptera: Pseudococcidae), and cross-amplification in two other mealybug species

1Computational Biology and Population Genomics Group, Centro de Biologia Ambiental, Departamento de Biologia Animal, Faculdade de Ciencias da Universidade de Lisboa, 1749-016 Lisboa, Portugal 2Centro de Estudos Florestais, Instituto Superior de Agronomia, 1349-017 Lisboa, Portugal 3Centro de Estudos do Ambiente e do Mar (CESAM), Departamento de Biologia Animal, Faculdade de Ciencias da Universidade de Lisboa, 1749-016 Lisboa, Portugal 4Centro de Engenharia dos Biossistemas, Instituto Superior de Agronomia, 1349-017 Lisboa, Portugal 5Department of Entomology, Agricultural Research Organization, The Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel

4Pipe4 – A 454 data analysis pipeline for SNP detection in datasets with no reference sequence or strain information

BackgroundNext-generation sequencing datasets are becoming more frequent, and their use in population studies is becoming widespread. For non-model species, without a reference genome, it is possible from a panel of individuals to identify a set of SNPs that can be used for further population genotyping. However the lack of a reference genome to which the sequenced data could be compared makes the finding of SNPs more troublesome. Additionally when the data sources (strains) are not identified (e.g. in datasets of pooled individuals), the problem of finding reliable variation in these datasets can become much more difficult due to the lack of specialized software for this specific task.ResultsHere we describe 4Pipe4, a 454 data analysis pipeline particularly focused on SNP detection when no reference or strain information is available. It uses a command line interface to automatically call other programs, parse their outputs and summarize the results. The variation detection routine is built-in in the program itself. Despite being optimized for SNP mining in 454 EST data, it is flexible enough to automate the analysis of genomic data or even data from other NGS technologies. 4Pipe4 will output several HTML formatted reports with metrics on many of the most common assembly values, as well as on all the variation found. There is also a module available for finding putative SSRs in the analysed datasets.ConclusionsThis program can be especially useful for researchers that have 454 datasets of a panel of pooled individuals and want to discover and characterize SNPs for subsequent individual genotyping with customized genotyping arrays. In comparison with other SNP detection approaches, 4Pipe4 showed the best validation ratio, retrieving a smaller number of SNPs but with a considerably lower false positive rate than other methods.4Pipe4’s source code is available at https://github.com/StuntsPT/4Pipe4.