Mitochondrial differentiation and biogeography of Hyla meridionalis (Anura: Hylidae): an unusual phylogeographical pattern

Aim To study the patterns of genetic variation and the historical events and processes that influenced the distribution and intraspecific diversity in Hyla meridionalis Boettger, 1874. Location Hyla meridionalis is restricted to the western part of the Mediterranean region. In northern Africa it is present in Tunisia, Algeria and Morocco. In south‐western Europe it is found in the south of France, north‐western Italy and north‐eastern and south‐western Iberian Peninsula. There are also insular populations, as in the Canaries and Menorca. Methods Sampling included 112 individuals from 36 populations covering the range of the species. We used sequences of mitochondrial DNA Cytochrome Oxidase I (COI) for the phylogeographical analysis (841 bp) and COI plus a fragment including part of tRNA lysine, ATP synthase subunits 6 and 8 and part of Cytochrome Oxidase III for phylogenetic analyses (2441 bp). Phylogenetic analyses were performed with paup *4.0b10 (maximum likelihood, maximum parsimony) and Mr Bayes 3.0 (Bayesian analysis). Nested clade analysis was performed using tcs 1.18 and Geo Dis 2.2. A dispersal‐vicariant analysis was performed with diva 1.0 to generate hypotheses about the geographical distribution of ancestors. Results We found little genetic diversity within samples from Morocco, south‐western Europe and the Canary Islands, with three well‐differentiated clades. One is distributed in south‐western Iberia and the High Atlas, Anti‐Atlas and Massa River in Morocco. The second is restricted to the Medium Atlas Mountains. The third one is present in northern Morocco, north‐eastern Iberia, southern France and the Canaries. These three groups are also represented in the nested clade analysis. Sequences from Tunisian specimens are highly divergent from sequences of all other populations, suggesting that the split between the two lineages is ancient. diva analysis suggests that the ancestral distribution of the different lineages was restricted to Africa, and that an explanation of current distribution of the species requires three different dispersal events. Main conclusions Our results support the idea of a very recent colonization of south‐western Europe and the Canary Islands from Morocco. South‐western Europe has been colonized at least twice: once from northern Morocco probably to the Mediterranean coast of France and once from the western coast of Morocco to southern Iberia. Human transport is a likely explanation for at least one of these events. Within Morocco, the pattern of diversity is consistent with a model of mountain refugia during hyperarid periods within the Pleistocene. Evaluation of the phylogenetic relationships of Tunisian haplotypes will require an approach involving the other related hylid taxa in the area.     

Syntaxonomic analysis of theAndropogon-rich grasslands (Hyparrhenietalia hirtae) in the western Mediterranean region

Using the Braun-Blanquet approach, a syntaxonomical revision of the orderHyparrhenietalia hirtae in the western Mediterranean region was made. Various syntaxa were studied with relevés from the Iberian Peninsula, southern France, Sardinia, Sicily and adjacent islands, Balearic Islands, Canary Islands and Morocco. One alliance (Hyparrhenion hirtae), 8 associations (one of them new:Lotononido lupinifoliae-Hyparrhenietum sinaicae) and several subassociations and variants were distinguished. A complete classification of theHyparrhenietalia hirtae in the studied area with ecological and biogeographical diagnoses is given.     

Spot variation in Maniola jurtina (L.) (Lepidoptera: Satyridae) in southern Portugal and a comparison with the Canary Islands

A sample of 2013 meadow brown butterflies, Maniola jurtina , was obtained in the Algarve, southern Portugal, on behalf of E.B. Ford, the founder of ecological genetics. Variation in the meadow brown occupied Ford's attention for more than 40 years. Ford died in 1988; most of his collection had earlier been destroyed, but the meadow browns remained and became available for analysis. The butterflies were scored for spotting characters on both fore- and hindwings. The population is homogeneous over the entire area of the Algarve and there is no conclusive evidence of a difference between the two years of collection (1986 and 1987). It is probably also homogeneous with southern Iberia in general, an area unique in the western Palaearctic range of the species as it is characterized by a high spot average in males and a low spot average in females. Algarve butterflies differ markedly from those of the Canary Islands, where there is considerable inter-island heterogeneity, supporting the view that the Canary Island populations did not originate from southern Iberia. In the Algarve, many females aestivate and by September there is an essentially all-female population. These are low-spotted and differ significantly from females active in May and June at the start of the annual (one generation) flight season.     

A combined barcode and morphological approach to the systematics and biogeography of Laurencia pyramidalis and Laurenciella marilzae (Rhodophyta)

In the present study we undertook an integrative approach, using both morphological and molecular data (COI-5P + rbcL), to assess the presence of Laurencia pyramidalis in Lusitanian Macaronesia. We studied type material of L. pyramidalis from the herbarium of the Naturalis Biodiversity Center, the Netherlands, and designated a lectotype and syntypes. Vegetative and reproductive features of L. pyramidalis were observed and we included a specimen from the type locality in our molecular analyses. We also investigated the geographical distribution of Laurenciella marilzae, a species recently described from the Canary Islands. Barcode sequences (COI-5P and rbcL) were generated for L. pyramidalis from the type locality (Normandy, France), the Azores, Madeira and the Canary Islands, and for L. marilzae from its type locality (Tenerife, Canary Islands), the Azores and Brazil.     

Balearic insular isolation and large continental spread framed the phylogeography of the western Mediterranean Cheirolophus intybaceus s.l. (Asteraceae)

Recent Quaternary geological and climate events have shaped the evolutionary histories of plant species in the Mediterranean basin, one of the most important hotspots of biodiversity. Genetic analyses of the western Mediterranean Cheirolophus intybaceus s.l. (Asteraceae) based on AFLP were conducted to establish the relationships between its close species and populations, to reconstruct the phylogeography of the group and to analyse potential unidirectional versus bidirectional dispersals between the Ibero‐Provençal belt and the Balearic Islands. AFLP data revealed two main genetic groups, one constituted by the Balearic populations and Garraf (NE Iberia) and the other formed by the remaining mainland populations that were further sub‐structured into two geographically separated subgroups (SE + E Iberia and NE Iberia + SW France). Genetic diversity and spatial structure analyses suggested a mid‐Pleistocene scenario for the origin of C. intybaceus in southern Iberia, followed by dispersal to the north and a single colonisation event of the Balearic archipelago from the near Dianic NE Iberian area. This hypothesis was supported by paleogeographic data, which showed the existence of terrestrial connections between the continent and the islands during the Middle–Late Pleistocene marine regressions, whereas the more recent single back‐colonisation of the mainland from Mallorca might be explained by several hypotheses, such as long‐distance dispersal mediated by migratory marine birds or sea currents.     

PHYLOGEOGRAPHIC STUDIES IN THE TROPICAL SEAWEED CLADOPHOROPSIS MEMBRANACEA (CHLOROPHYTA,ULVOPHYCEAE) REVEAL A CRYPTIC SPECIES COMPLEX1

The seaweed Cladophoropsis membranacea (Hofman Bang ex. C. Agardh) Børgesen is a widely distributed species on coral reefs and along rocky coastlines throughout the tropics and subtropics. In a recent population‐level survey openface>1600 individuals with eight microsatellite loci, a number of isolates from biogeographically disjunct locations could not be amplified for any of the loci. Nonamplifiable and amplifiable isolates co‐occurred within the Canary Islands, Cape Verde Islands, and in the Caribbean. These unexpected results led to question whether or not C. membranacea is a single species. Phylogenetic relationships were evaluated using rDNA ITS1 and ITS2 sequence comparisons from 42 isolates sampled from a subset of 30 of the 66 locations. Four well‐supported clades were identified. Sequence divergence within clades was <1%, whereas between‐clade divergence was 2%–3%. Intraindividual variation was extremely low with no effects on the analysis. A strong, but imperfect, correspondence was found between ITS clades and amplifiable microsatellite loci. It is concluded that C. membranacea consists of three cryptic species. Using Pacific isolates as an outgroup, the most basal clade included the Central Canary Islands, Cape Verde, and Bonaire (Caribbean) isolates and thus spanned the widest latitude. Two derived sister clades consisted of a southern transtropical group stretching across the SE Caribbean to the Cape Verde Islands and African coast (but not the Canary Islands) and a NE‐Canary Island‐Mediterranean clade that also included the Red Sea. The detection of overlapping biogeographic distributions highlights the importance of ecotypic differentiation with respect to temperature and the importance of shifting sea surface isotherms that have driven periodic extinctions and recolonizations of the Canary Islands—a crossroads of marine floral exchange—since the last glacial maximum.     

Range expansion and ancestral niche reconstruction in the Mediterranean diving beetle genus Meladema (Coleoptera,Dytiscidae)

Species of the genus Meladema (Dytiscidae, Colymbetinae) are some of the largest macroinvertebrates in the western Palearctic region, being top predators in fishless streams. Two of the three described species, Meladema imbricata (Wollaston, 1871) and Meladema lanio (Fabricius, 1775) are Macaronesian endemics from the Canary Islands and Madeira, respectively, while the third, Meladema coriacea Laporte, 1835, is widely distributed from Morocco and the Iberian Peninsula to Turkey, including the Canary Islands. Previous phylogenetic analysis using only mitochondrial markers revealed the existence of two cryptic lineages within M. coriacea, one restricted to Corsica and the other including the rest of sampled populations. We reconstruct here the evolutionary history of the species of Meladema using a more comprehensive sampling covering its whole geographical range, adding nuclear markers and Bayesian molecular dating. Using environmental niche modelling, we test for possible differences in climatic preferences among lineages and reconstruct their ancestral climatic niche. Our results strongly supported the existence of four monophyletic lineages represented by the three recognized species plus a fourth cryptic lineage with populations of M. coriacea from the Tyrrhenian islands (Corsica, Sardinia and Montecristo). This pattern is not likely to be the result of mitochondrial artefacts due to Wolbachia infection, as all 11 tested individuals were negative for this parasite. Dating analysis placed the origin of Meladema in the Middle Miocene although diversification among extant Meladema lineages started in the early Pleistocene and took place in a relatively short time period. Phylogeographic analysis inferred a continental origin of Meladema, with an independent colonization of the Macaronesian and Mediterranean islands. From the south‐western Mediterranean region, the continental M. coriacea expanded its range up to Bulgaria and Turkey in the northern basin and to Tunisia in the southern. Results of niche modelling showed that seasonality is the critical factor in shaping the current distribution of Meladema. Island lineages (M. imbricata, M. lanio and the Tyrrhenian lineage of M. coriacea) occur in sites with low seasonality, within the range of the reconstructed ancestral climatic niche of the genus. On the contrary, continental M. coriacea expanded its range to localities outside the ancestral climatic range of the genus, with a higher seasonality and aridity.     

Population history,gene flow,and bottlenecks in island populations of a secondary seed disperser,the southern grey shrike (Lanius meridionalis koenigi)

Studying the population history and demography of organisms with important ecological roles can aid understanding of evolutionary processes at the community level and inform conservation. We screened genetic variation (mtDNA and microsatellite) across the populations of the southern grey shrike (Lanius meridionalis koenigi) in the Canary Islands, where it is an endemic subspecies and an important secondary seed disperser. We show that the Canarian subspecies is polyphyletic with L. meridionalis elegans from North Africa and that shrikes have colonized the Canary Islands from North Africa multiple times. Substantial differences in genetic diversity exist across islands, which are most likely the product of a combination of historical colonization events and recent bottlenecks. The Eastern Canary Islands had the highest overall levels of genetic diversity and have probably been most recently and/or frequently colonized from Africa. Recent or ongoing bottlenecks were detected in three of the islands and are consistent with anecdotal evidence of population declines due to human disturbance. These findings are troubling given the shrike's key ecological role in the Canary Islands, and further research is needed to understand the community‐level consequences of declines in shrike populations. Finally, we found moderate genetic differentiation among populations, which largely reflected the shrike's bottleneck history; however, a significant pattern of isolation‐by‐distance indicated that some gene flow occurs between islands. This study is a useful first step toward understanding how secondary seed dispersal operates over broad spatial scales.     

Colonization patterns and genetic structure of peripheral populations of the trumpeter finch (Bucanetes githagineus) from Northwest Africa, the Canary Islands and the Iberian Peninsula

Aim This paper has three aims: (1) to reconstruct the colonization history of two peripheral populations of the trumpeter finch (Bucanetes githagineus) presumably originating from the same source, one the result of an ancient expansion process and the other recently established and still expanding; (2) to estimate the importance of key events, such as past and current gene flow and bottlenecks, in both expansion processes and their contribution to the present population structure and genetic diversity; and (3) to find out whether two peripheral populations that established at widely differing times also differ in terms of genetic diversity. Location Northwest Africa (assumed source population), Canary Islands (long‐established peripheral) and south‐eastern Iberian Peninsula (recently established peripheral). Methods Bayesian analysis of population structure, individual assignment tests, F‐statistics, maximum likelihood migration estimates, genetic diversity indices and bottleneck tests were calculated with microsatellite data from 194 trumpeter finches from five breeding and two seasonal non‐breeding sites. Results Our data support the existence of two subpopulations (Canary Island and Ibero‐African) as the most likely population structure. Seasonal sites in the Iberian Peninsula had the highest percentage of birds assigned to other, mainly Iberian, sites. Pairwise F_ST values showed that the Canary Island localities were very similar to each other, but differed from the rest. Gene flow estimates within subpopulations were only slightly higher in the Canary Island population than in the Ibero‐African one. Gene diversity indices were similar at all localities. Canary Island sites show evidence of bottlenecks, whereas the Ibero‐African sites do not. Main conclusions Our data show that, at present, birds from the Canary Islands are genetically differentiated from those in North Africa and continental Spain. We could not unequivocally confirm the African origin of Canary populations because the contrary is also plausible. The Iberian Peninsula seems to have repeatedly received individuals from North Africa, which would have led to the relatively high genetic diversity found in these recently established localities and prevented bottlenecks. Movements of individuals towards sites outside their current range during the non‐breeding season are likely to precede the establishment of new breeding sites at the periphery of the distribution range.     

Genetic Diversity of Frankia Microsymbionts from the Relict Species Myrica faya (Ait.) and Myrica rivas-martinezii (S.) in Canary Islands and Hawaii

In the Western Canary Islands, Myrica faya and Myrica rivas-martinezii (Myricaceae) are phylogenetically close, endemic, actinorhizal species presumed to be remnants either of the European or the African Tertiary floras. Unisolated Frankia strains from field-collected nodules on Tenerife, Gomera, and La Palma Islands were compared by their rrs gene and 16S–23S intergenic spacer (IGS) restriction patterns. To compare the genetic diversity of Frankia strains from within and outside the host’s native range, nodules of M. faya field plants were collected both in Canary Islands and in Hawaii, where this species is an exotic invasive. Myrica rivas-martinezii, endemic to the Canary Islands, was sparsely nodulated in the field. Frankia strains harbored in field-collected nodules of M. faya and M. rivas-martinezii belonged to the Elaeagnaceae strains’ genetic cluster and exhibited a high degree of diversity. Frankia genotypes were specific to each host species. In the Canary archipelago, we found no relationship between site of collection and Frankia genotype for M. faya. The only exceptions were strains from site 2 in Tenerife, a location with a geological history different from the other sites sampled. Hawaiian and Canarian M. faya strains had no genotypes in common, raising questions concerning the origin of M. faya-infective Frankia in Hawaii. Nodular strains of M. rivas-martinezii from nursery plants were genetically characterized and shown to be divergent from the strains of field-collected nodules and belong to the Alnus-Casuarina strains cluster. This suggests Myrica may have the potential to nodulate with a broader range of Frankia genotypes under artificial conditions than has been detected in field-collected nodules.     

Life‐history parameters and predation capacity of Macrolophus pygmaeus and Nesidiocoris tenuis (Hemiptera: Miridae) on eggs of Plutella xylostella (Lepidoptera: Plutellidae)

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Molecular biogeography of the arctic-alpine disjunct burnet moth species Zygaena exulans (Zygaenidae, Lepidoptera) in the Pyrenees and Alps

Aim The phylogeography of ‘southern’ species is relatively well studied in Europe. However, there are few data about ‘northern’ species, and so we studied the population genetic structure of the arctic‐alpine distributed burnet moth Zygaena exulans as an exemplar. Location and methods The allozymes of 209 individuals from seven populations (two from the Pyrenees, five from the Alps) were studied by electrophoresis. Results All 15 analysed loci were polymorphic. The mean genetic diversities were moderately high (A: 1.99; H_e: 11.5; P: 65%). Mean genetic diversities were significantly higher in the Alps than in the Pyrenees in all cases. F_ST was 5.4% and F_IS was 10%. Genetic distances were generally low with a mean of 0.022 between large populations. About 62% of the variance between populations was between the Alps and the Pyrenees. The two samples from the Pyrenees had no significant differentiation, whereas significant differentiation was detected between the populations from the Alps (F_ST = 2.8%, P = 0.02). Main conclusion Zygaena exulans had a continuous distribution between the Alps and the Pyrenees during the last ice age. Most probably, the species was not present in Iberia, and the samples from the Pyrenees are derived from the southern edge of the glacial distribution area and thus became genetically impoverished. Post‐glacial isolation in Alps and Pyrenees has resulted in a weak genetic differentiation between these two disjunct high mountain systems.     

The revenant: rediscovery of Margaritifera homsensis from Orontes drainage with remarks on its taxonomic status and conservation (Bivalvia: Margaritiferidae)

Since Margaritifera marocana (Pallary, 1918) and M. laosensis (Lea, 1863) were rediscovered, M. homsensis (Lea, 1865) remains the only pearl mussel species known solely based on old shell samples from natural history museums. This is also the last pearl mussel species, which is absent in a phylogeny of the family. Here, we aimed to provide an integrative revision of the taxonomic status of M. homsensis from the Orontes Basin. Using a newly collected specimen from the River Karasu, Hatay Province, southern Turkey, five gene partitions were sequenced, the cytochrome c oxidase subunit I (COI), large ribosomal subunit rRNA (16S), large ribosomal subunit rDNA (28S) and its D3 expansion segment (D3), and small ribosomal subunit rDNA (18S). The multi-gene phylogeny indicates that M. homsensis is a sister taxon of M. auricularia, but both these species are closely related to M. marocana by nuclear genes. The main conchological features, i.e., the shell shape, teeth morphology, and mantle attachment scars, as well as Fourier shell shape analysis have not shown principal differences between M. homsensis and M. auricularia. Based on these data, we concluded that M. homsensis is a valid species that is most closely related to M. auricularia. Special conservation efforts for a population of M. homsensis discovered in Turkey, including the formation of a nature reserve, might contribute to the conservation of the species. Finally, an extensive search for surviving populations in Orontes drainage (southern Turkey, Lebanon, and Syria) and the Nahr-el-Kabir River (Lebanon and Syria) remains necessary to develop a transboundary conservation strategy for this unique taxon.     

From Scilla to Charybdis – is our voyage safer now?

The genus Charybdis Speta (previously Urginea maritima agg.) was investigated karyologically and genetically throughout its geographic range in the Mediterranean. The different ploidy levels show a strong geographic pattern. Diploid populations are mainly found along the northern coast of Africa with C. pancration extending northwards from Tunisia to southern Italy. Tetraploid populations are most densely distributed in the eastern Mediterranean but are also found in North Africa, on the Balearic and Canary Islands. Hexaploid populations are restricted to the Iberian Peninsula and adjacent Morocco and Algeria. Chloroplast microsatellite data suggest that determination of ploidy levels alone is insufficient to adequately describe the existing populations. Especially the tetraploid and hexaploid populations exhibit additional genetic differentiation and geographic structuring. AFLP data indicate that tetraploid populations from southern Italy are of hybrid origin. Phylogenetic analysis further revealed that the genera Urginea Steinh. and Charybdis are not directly related to each other but have strong ties to genera from southern Africa. A possible colonization scenario of the Mediterranean via NW Africa and Iberia is discussed.     

Genetic distance between Nasutitermes takasagoensis (Isoptera: Termitidae) populations in Taiwan and the Yaeyama Islands, analyzed by amplified fragment length polymorphism markers

Dispersal ability and degree of inbreeding in a population can indirectly be assessed using genetic markers. It has been suggested that winged termites are not able to fly distances greater than several hundred meters. Using the amplified fragment length polymorphism (AFLP) technique, we previously analyzed the population substructure of Nasutitermes takasagoensis in the Yaeyama Islands, southern Japan. We found that there is moderate subpopulation structure based on the AFLP data. Moreover, the relatively low G_st and genetic distances among insular populations suggest that there is a possibility that winged termites are able to fly over distances of several kilometers. To learn more about this, in the present study, we compared new samples collected from the Hengchuen Peninsula in southern Taiwan with samples previously collected from the Yaeyama Islands. Using the samples collected in Taiwan, genetic distance was calculated against samples from six of the Yaeyama Islands. Genetic diversity, average heterozygosity, percentage of polymorphic loci, G_st and gene flow (Nm) were calculated. A total of 155 AFLP fragments were obtained for three primer combinations used, with 8 (5%) polymorphic bands. Genetic distance between the populations of Taiwan and the rest of the islands was greater than the genetic distance among the Yaeyama Islands. Although previous studies showed that average Nm among the Yaeyama Islands was 2.47, all of the observed Nm between Taiwan and the Yaeyama Islands were below 1. These findings suggest that the geographic distance between Taiwan and the Yaeyama Islands is large enough to prevent gene flow between them.     

REVISION OF THE GENUS NAPAEUS ALBERS, 1850 (GASTROPODA PULMONATA: ENIDAE). THE PROBLEM OF NAPAEUS (NAPAEINUS) NANODES (SHUTTLEWORTH, 1852) AND DESCRIPTION OF FIVE NEW SPECIES FROM ITS CONCHOLOGICAL GROUP

With this paper we initiate a taxonomic review of the genusNapaeus from the Canary Islands, indicating the statisticalmethodology used therein. We discuss the taxonomic problem ofNapaeus (Napaeinus) nanodes (Shuttleworth, 1852), designateits lectotype and describe five new species: Napaeus (Napaeinus)doliolum Henríquez, Napaeus (Napaeinus) bechi Alonso& Ibáñez, Napaeus (Napaeus) taguluchensisHenríquez, Napaeus (Napaeus) pygmaeus Ibáñez& Alonso and Napaeus (Napaeus) tagamichensis Henríquez,the first two from Tenerife; and the other three from La Gomera.Furthermore, we discuss the general relationships of the genusand its two sub-genera, whose original diagnoses are deficient;because of this, we think that in the future a broad reviewof the subfamily Eninae will be necessary in order to clarifythe actual position of this subfamily in the Canary Islands. (Received 11 March 1991; accepted 22 September 1992)     

The Genus Obelus Hartmann, 1842 (Gastropoda, Pulmonata, Helicoidea) and its Phylogenetic Relationships

The genus Obelus, so far known from shells only, is re-described on the basis of the anatomy of its genital system. Its range is here restricted to north-western Africa and the Canary Islands. Four species are traditionally listed for the Canary Islands: Obelus despreauxii, O. moderatus, O. mirandae and O. cyclodon. The presence of the last species on the Canary Islands is doubtful, whereas the fossil/subfossil presence of O. pumilio is documented. The species Helix morata also belongs to the genus, as well as a new species, O. discogranulatus sp. nov. The genital systems of all confirmed extant Canarian species are shown. Obelus has a peculiar vaginal stimulator appendix (“appendicula”) which is homologous to the penial appendix of the Orthurethra and to the stimulatory organ of other Stylommatophora, with the exception that the A₃ portion is missing. The genus is diagnosed by characters of the vaginal stimulator appendix, such as a curved, finger-like A₂ portion of the appendicula ending proximally in a blind, well-developed muscular sac, and by the slender tubular A₄ portion arising laterally from the muscular sac duct. We conclude that Obelus belongs to the Cochlicella group because it shares an appendicula with the other genera of the group. However, it differs in anatomical details of this structure. The Cochlicella group should be recognized as a separate family Cochlicellidae Schileyko, 1972, with close relationships to the Helicellidae and the Hygromiidae. A new diagnosis for Cochlicellidae is proposed and its phylogenetic relationships are discussed.This is: Notes on the Malacofauna of the Canary Islands, No. 46.     

Low diversity but high differentiation: the population genetics of Aglaope infausta (Zygaenidae: Lepidoptera)

Aim Aglaope infausta is a thermophilous Zygaenid of Atlanto-Mediterranean origin, distributed in Portugal, Spain, France and north-western Italy reaching its north-eastern distribution limit in western Germany. The local, regional and inter-regional genetic structure of this species is studied in this analysis. Location and methods The allozymes of 456 individuals from 12 populations (11 from western Germany and one from southern Portugal) were studied by electrophoresis. Results Six of the 19 loci analysed were monomorphic. Genetic differentiation between populations was high (F_ST: 0.404), while the mean genetic diversity was low (H_e: 3.4%). Most (96.5%) of the genetic variance between populations was between the Portuguese and the German samples, but also the differentiation within Germany was considerable (F_SR: 0.101). In Germany, A. infausta occurs in two major regions (middle Rhine and Nahe) that are geographically separated, and 55.5% of the genetic variance was found between these two regions. The populations of both areas do not differ in their genetic diversity, but those of the middle Rhine have significantly higher genetic distances among them than the Nahe populations (0.020 and 0.015, respectively). F_ST was also higher in the middle Rhine region than in the Nahe region (0.089 and 0.045, respectively). Main conclusions Aglaope infausta shows a very low level of genetic heterogeneity for a lepidopteran species. However, this genetic poverty is not affecting the species’ viability. During the ice ages, differentiation into two genetic lineages occurred, most probably in a south-western and a south-eastern differentiation centre in Iberia. The gap in the distribution range in Germany is clearly reflected in the genetic structure. This differentiation must have developed relatively quickly because western Germany most probably was colonized during the climatic optimum 6000 years ago.     

Microbial community of predatory bugs of the genus Macrolophus(Hemiptera: Miridae)

Background

The predatory mirids of the genus Macrolophus are key natural enemies of various economically important agricultural pests. Both M. caliginosus and M. pygmaeus are commercially available for the augmentative biological control of arthropod pests in European greenhouses. The latter species is known to be infected with Wolbachia -inducing cytoplasmic incompatibility in its host- but the presence of other endosymbionts has not been demonstrated. In the present study, the microbial diversity was examined in various populations of M. caliginosus and M. pygmaeus by 16S rRNA sequencing and denaturing gradient gel electrophoresis.

Results

Besides Wolbachia, a co-infection of 2 Rickettsia species was detected in all M. pygmaeus populations. Based on a concatenated alignment of the 16S rRNA gene, the gltA gene and the coxA gene, the first is phylogenetically related to Rickettsia bellii, whereas the other is closely related to Rickettsia limoniae. All M. caliginosus populations were infected with the same Wolbachia and limoniae-like Rickettsia strain as M. pygmaeus, but did not harbour the bellii-like Rickettsia strain. Interestingly, individuals with a single infection were not found. A PCR assay on the ovaries of M. pygmaeus and M. caliginosus indicated that all endosymbionts are vertically transmitted. The presence of Wolbachia and Rickettsia in oocytes was confirmed by a fluorescence in situ hybridisation. A bio-assay comparing an infected and an uninfected M. pygmaeus population suggested that the endosymbionts had minor effects on nymphal development of their insect host and did not influence its fecundity.

Conclusion

Two species of the palaearctic mirid genus Macrolophus are infected with multiple endosymbionts, including Wolbachia and Rickettsia. Independent of the origin, all tested populations of both M. pygmaeus and M. caliginosus were infected with three and two endosymbionts, respectively. There was no indication that infection with endosymbiotic bacteria had a fitness cost in terms of development and fecundity of the predators.

     

Life history of the red-banded seabream Pagrus auriga (Sparidae) from the coasts of the Canarian archipelago

Red‐banded seabream Pagrus auriga (N = 615) were caught off the Canary Islands from January 2003 to December 2004. Total length ranged from 120 to 780 mm. The species was characterized by protogynous hermaphroditism. The male :female ratio was in favour of females (1 : 8.2). The reproductive season extended from September to February, with a peak in spawning activity in October–November. Fifty percentage maturity was reached at 387 mm total length by females and 533 mm by males. The length–weight relationship for all individuals was described by the parameters: a = 0.0086 and b = 3.014, when length is given in mm and weight in grams. Otolith age readings indicated that the population consists of 19 age groups, including a very high proportion of individuals between 0 and 7 years old. Growth analysis reveals that the species is slow‐growing and relatively long lived (18 years). The von Bertalanffy growth parameters for the entire population were: L_∞ = 803 mm, k = 0.081 year⁻¹ and t₀ = −2.17 year. Growth differed between males and females. The instantaneous rate of natural mortality for all fish was: M = 0.164 year⁻¹.