Mitochondrial COI Sequences Research Articles

Evidence of incomplete lineage sorting or restricted secondary contact in Lateolabrax japonicus complex (Actinopterygii: Moronidae) based on morphological and molecular traits

To clarify the taxonomic delimitation of the Lateolabrax japonicus complex, we conducted morphological and molecular analyses of 79 individuals collected from 10 localities in Korea. Assignment of individuals into three types (sea bass [SB], spotted sea bass [SSB] and intermediate sea bass [ISB]) was performed according to the presence/absence of black spots, and the distribution of black spots if present. Results of a canonical discriminant analysis showed that SB and ISB are closely related, but SSB is distinct from SB + ISB. Based on mitochondrial DNA COI sequences (507 bp), SB and ISB clustered together, and this cluster was distinct from that of SSB (d = 0.072–0.085). STRUCTURE analysis using six microsatellite markers showed the existence of two genetically differentiated groups (SB + ISB and SSB). However, ISB had a greater number of mixed individuals than SB and SSB, and was located distantly far from SB in the PCoA axis 2, implying restricted secondary contact within L. japonicus complex.

Looking beneath the tip of the iceberg: diversification of the genus Epimeria on the Antarctic shelf (Crustacea, Amphipoda)

The amphipod genus Epimeria is very speciose in Antarctic waters. Although their brooding biology, massive and heavily calcified body predict low dispersal capabilities, many Epimeria species are documented to have circum-Antarctic distributions. However, these distribution records are inevitably dependent on the morphological species definition. Yet, recent DNA evidence suggests that some of these Epimeria species may be complexes of species with restricted distributions. Mitochondrial COI and nuclear 28S rDNA sequence data were used to infer evolutionary relationships among 16 nominal Epimeria species from the Antarctic Peninsula, the eastern Weddell Sea and the Adelie Coast. Based on this phylogenetic framework, we used morphology and the DNA-based methods GMYC, bPTP and BPP to investigate species boundaries, in order to revise the diversity and distribution patterns within the genus. Most of the studied species appeared to be complexes of pseudocryptic species, presenting small and previously overlooked morphological differences. Altogether, 25 lineages were identified as putative new species, increasing twofold the actual number of Antarctic Epimeria species. Whereas most of the species may be geographically restricted to one of the three studied regions, some still have very wide distribution ranges, hence suggesting a potential for large-scale dispersal.

Combined evidence indicates that Perna indica Kuriakose and Nair 1976 is Perna perna (Linnaeus, 1758) from the Oman region introduced into southern India more than 100 years ago

The specific status of the brown mussel, Perna indica, in southern India and northern Sri Lanka has long been questioned. Its limited geographical distribution within the extensive range of the Asian green mussel, P. viridis, and its morphometric similarity to the African brown mussel, P. perna, have led several authorities to suggest that P. indica is not a distinct species but is in fact introduced P. perna. Analysis of DNA sequences for nuclear ITS and mitochondrial COI sequence data from newly collected mussels from southern India examined in the context of data from GenBank for mussels of the genus Perna reveals that P. indica is indeed P. perna from the Oman region. A literature review indicates that P. indica (now P. perna) has been established in southern India for at least 100 years. Reports of ecological interactions between the native P. viridis and the introduced P. perna reveal that P. perna grows to a larger size than P. viridis and outcompetes the native mussel. P. perna forms high density populations that have long been fished by local coastal communities and recently the fishery for P. perna has expanded to markets beyond the coastal area. Eradication of the introduced P. perna is not feasible and is not desirable given its important role as a source of protein and revenue for the local community. Because no monitoring of the range of P. perna in southern India occurs it is not possible to know if this species is increasing its area of distribution, but a qualitative assessment of ongoing range expansion is made based on limited evidence from published reports. The possibility exists for inter-specific hybridisation between P. viridis and P. perna and we recommend that testing commence to check for this. This research highlights the value of a detailed understanding of the genetic structure (four different clades) of the genus Perna, without which the status of P. indica as P. perna from Oman in southern India could not have been made.

Estimating diversity of crabs (Decapoda: Brachyura) in a no-take marine protected area of the SW Atlantic coast through DNA barcoding of larvae

DNA barcoding was used to identify crab larvae from the Marine Biological Reserve of Arvoredo, encompassing a coastal archipelago off the SW Atlantic coast (27°S, 48°W). Partial mitochondrial COI or 16S rRNA gene sequences were obtained for 488 larvae, leading to the identification of 20 species. The COI sequences generated 13 barcode index numbers (BINs) within Barcode of Life Data Systems (BOLD), among which 11 were concordant with single species. DNA from ∼ 6% of the larvae did not amplify using the primers tested; based on external morphological characteristics, these larvae represented four possible additional operational taxonomic units (OTUs) at the family level. Intraspecific variation for the COI and 16S rRNA genes was found to be < 2.6% and < 2.1% respectively (Kimura 2-parameter distance), whereas interspecific divergence ranged from 7.9% to 21.5% and 6.4% to 14.5%, respectively. These results imply that both genes are suitable for use in species identification of brachyuran crabs of this area. Molecular identification of this group successfully enabled the diagnosis of larvae of closely related species, including congeners in Mithrax, Achelous and Callinectes. In addition, eight out of 20 species recognized represent new records for the reserve suggesting that the brachyuran fauna in the area has been underestimated based on traditional biodiversity measures. The availability of primers suited to the targeted species, and the development of a taxonomically comprehensive DNA barcoding database are the major recommendations to improve the accuracy and feasibility of using DNA barcoding for species identification of SW Atlantic brachyuran crabs.

A new genus and twenty new species of Australian jumping plant-lice (Psylloidea: Triozidae) from Eremophila and Myoporum (Scrophulariaceae: Myoporeae).

The Triozidae is a diverse, cosmopolitan family of jumping plant-lice (Hemiptera: Psylloidea) from an exceptionally diverse range of plant families, but with few described Australian species. As a direct outcome of the Australian Biological Resources Study Bush Blitz species discovery program, many new Psylloidea from novel host plants in remote localities have been revealed. In this study a new genus Myotrioza Taylor gen. nov. and 20 new species are described from southern and central Australia which also establishes the first host plant records from Eremophila and Myoporum (Scrophulariaceae: Myoporeae). New species, delineated using a combination of morphological and mitochondrial COI sequence data, are: Myotrioza clementsiana sp. nov., M. darwinensis sp. nov., M. desertorum sp. nov., M. eremi sp. nov., M. eremophili sp. nov., M. flindersiana sp.nov., M. gawlerensis sp. nov., M. insularis sp. nov., M. interioris sp. nov., M. interstantis sp. nov., M. longifoliae sp. nov., M. markmitchelli sp. nov., M. myopori sp. nov., M. oppositifoliae sp. nov., M. pantonii sp. nov., M. platycarpi sp. nov., M. remota sp. nov., M. scopariae sp. nov., M. serrulatae sp. nov., and M. telowiensis sp. nov. Genetic divergence data, host associations, biogeographic data, diagnoses and a key to species are presented. Myotrioza appears to be particularly diverse in ephemeral southern Australia, especially in inland Western Australia and South Australia, matching regions of high diversity of the host genera; some species are likely to be short range endemics.

Behavior and population structure of Anopheles darlingi in Colombia

Anopheles darlingi is a widely distributed and important malaria vector in Colombia. Biogeographical and ecological heterogeneity across the Colombian distribution led to the hypothesis of behavioral and genetic differentiation among A. darlingi populations. A total of 2017 A. darlingi specimens were collected during 222h of sampling. This vector was the most abundant anopheline species in most of the localities sampled. Subdivision between samples collected west and east of the Andes was indicated by 1) mitochondrial COI and nuclear CAD sequences from NW-W and CE-S populations (COI ΦST=0.48761–0.81974, CAD FST=0.11319–0.21321), 2) a COI haplotype network, and 3) SAMOVA. Endo- and exophagy were detected in populations west of the Andes, whereas exophagy was evident in PTG, a locality east of the Andes. Isolation by resistance was significant for COI and explained 26% of the genetic differentiation. We suggest that at a macrogeographic scale, the Andes influence the differentiation of A. darlingi in Colombia and may drive divergence, and, at a microgeographic scale, ecological differences have a significant impact on structure. These data could constitute a baseline for the design of effective vector interventions, locality-specific for the east and similar for panmictic populations west of the Andes.

Molecular phylogenetic analyses of tissue coccidia (sarcocystidae; apicomplexa) based on nuclear 18s RDNA and mitochondrial COI sequences confirms the paraphyly of the genus Hammondia

SUMMARYPartial mitochondrial cytochromecoxidase subunit I (mt COI) sequences were generated from:Toxoplasma gondii(strains CTG, GTI, MAS, ME49, PTG, TgCatBr5, TgCat, Br64, TgCgCal, TgToucan);Neospora caninum(Strain NC1);Hammondia hammondi(Strain H.H–20);H. heydorni; H. cf.triffittae; Cystoisospora felis; C. suis; C. canis; C. rivolta; C. cf.ohioensis; Caryospora bigenetica; Sarcocystis rileyi; andS. neurona. Nuclear 18S rDNA sequences were generated forH. heydorni, H. hammondi, C. suis, C. canis, C. felis, C. rivolta, C. cf.ohioensis, S. neurona, andS. rileyi. Aligned, concatenated 18S rDNA and COI sequences were Bayesian analysed using partitioned nucleotide substitution models [HKY + I + G for 18S; GTR + I + G codon (code = metmt) for COI]. Phylogenetic hypotheses supported a monophyletic Sarcocystidae and its subfamilie with two major clades within the Toxoplasmatinae: (1) a monophyletic clade ofCystoisosporaspp. withNephroisospora eptesici; and (2) a clade ofToxoplasma, NeosporaandHammondia. Within the latter,Hammondiawas shown to be paraphyletic;H. heydorniandH. triffittaewere monophyletic withN. caninum[canine definitive hosts (DHs)], whereasH. hammondiwas monophyletic withT. gondii(feline DHs). A new genus is erected to resolve the paraphyly of the genusHammondiaconfirmed using mt COI and combined 18S/COI sequence datasets.

Genetic diversity of Parides ascanius (Lepidoptera: Papilionidae: Troidini): implications for the conservation of Brazil’s most iconic endangered invertebrate species

Parides ascanius (Lepidoptera: Papilionidae) is a butterfly endemic to the sand forests (“restingas”) of one of the most populated areas of Brazil (from Rio de Janeiro state to South Espirito Santo state), and was the first invertebrate officially recognized as being threatened in Brazil. Here we present a panel of eight polymorphic microsatellite loci and partial sequences of mitochondrial gene COI aiming to characterize this butterfly’s genetic diversity and understand its distribution among the extant populations. We estimate FST metrics, migration rates, cluster assignment, and spatial structure of genetic diversity. FST and statistics indicate low genetic structure and no evidence for endogamy, with all populations connected by high migration rates. Seven populations have low permanence rates (68–75 %) with increased migration probabilities for all populations. One population displays higher permanence rate (87.7 %), as the metropolitan matrix isolates it. Spatial analysis shows a global structure around the city of Rio de Janeiro and the Guanabara Bay; assignment analysis recovers six clusters evenly spread among sampled populations. These findings are consistent with a natural scenario of metapopulation dynamics for P. ascanius, with low genetic diversity and no endogamy, but progressively isolated by the metropolitan matrix. Conservation efforts should focus in connecting the isolated population, broaden the searches for new populations, and preserve all extant habitat patches where P. ascanius still occurs.

Genetic divergence analysis of the Common Barn Owl Tyto alba (Scopoli, 1769) and the Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile using COI sequence.

In this paper new mitochondrial COI sequences of Common Barn Owl Tyto alba (Scopoli, 1769) and Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile are reported and compared with sequences from other parts of the World. The intraspecific genetic divergence (mean p-distance) was 4.6 to 5.5% for the Common Barn Owl in comparison with specimens from northern Europe and Australasia and 3.1% for the Short-eared Owl with respect to samples from north America, northern Europe and northern Asia. Phylogenetic analyses revealed three distinctive groups for the Common Barn Owl: (i) South America (Chile and Argentina) plus Central and North America, (ii) northern Europe and (iii) Australasia, and two distinctive groups for the Short-eared Owl: (i) South America (Chile and Argentina) and (ii) north America plus northern Europe and northern Asia. The level of genetic divergence observed in both species exceeds the upper limit of intraspecific comparisons reported previously for Strigiformes. Therefore, this suggests that further research is needed to assess the taxonomic status, particularly for the Chilean populations that, to date, have been identified as belonging to these species through traditional taxonomy.

Genetic variation and population structure of the Pacific oyster Crassostrea gigas in the northwestern Pacific inferred from mitochondrial COI sequences

The Pacific oyster Crassostrea gigas as one of the important commercial bivalves in the world, is native to the coast of East Asia. The wild populations of this species have declined due to natural or anthropogenic factors in recent years. To provide valuable insights into management and conservation of C. gigas we investigated the genetic variation and population structure of C. gigas in the northwestern Pacific by analyzing partial mitochondrial cytochrome oxidase I gene (COI) with samples from 12 populations. Moderate levels of genetic diversity and low nucleotide diversity were found within the populations. No significant population structure existed in such a big spatial scale; only low but significant genetic differentiation between some of the Chinese and Japanese populations was observed, which highlighted the important roles of current gene flow and historical re-colonization in deceasing genetic differentiation for marine invertebrates with sedentary adults. The results obtained in this study provide useful information on the genetic diversity and phylogeographic pattern of C. gigas and reveal the complex interactions of multiple factors (strong genetic connectivity by dispersal of larvae and ocean currents in this region) in the northwestern Pacific.

Preliminary analyses reveal strong genetic structure in populations of Leucothoe vulgaris (Crustacea: Amphipoda: Leucothoidae) from Okinawa, Japan

Preliminary phylogenetic analyses of specimens of a leucothoid amphipod, Leucothoe vulgaris, collected from sponges, ascidians, and coral rubble from Okinawa, Japan, were completed using mitochondrial COI and nuclear 18S ribosomal DNA sequences. Analyses of sequences from 83 specimens demonstrate that populations of L. vulgaris likely entail at least two cryptic species, which are reciprocally monophyletic and reproductively isolated. These two potentially cryptic species live in sympatry but are apparently morphologically identical, suggesting a geographically driven divergence process and secondary contact. Within each clade, two major subclades corresponding to the east and west coast of Okinawa Island were present, with divergence times of approximately 1.61–1.83 mya. This last result suggests a role of Pleistocene sea level changes in the current patterns of intra-specific genetic structure and highlights the need for a more comprehensive sampling of L. vulgaris throughout the Indo-west Pacific.

Molecular insights into species recognition within southern Africa's endemicTricoliaradiation (Vetigastropoda: Phasianellidae)

The validity of morphology-based species boundaries between the southern African representatives of the genus Tricolia Risso, 1826 was assessed using mitochondrial COI and 16S rRNA sequence data. Most phylogenies obtained from individual and combined genetic datasets recovered 10 of the southern African members of the genus as a monophyletic clade. No COI sequences of the 11th species (T. adusta) were available, but this species clustered among the other African species in the 16S rRNA phylogeny. Discrepancies between morphology and genetics were identified in two clades within which there was limited genetic variation and no differentiation between two groups of nominal species, comprising respectivelyT. africana (Bartsch, 1915) andT. capensis (Dunker, 1846), andT. bicarinata (Dunker, 1846),T. insignis (Turton, 1932) and T. kraussi (Smith, 1911). In both cases the distributions of the nominal taxa coincide with well-known biogeographic disjunctions, and there is evidence of overlapping and intergrading shell characters. We propose that both of these unresolved clades be recognized as single, phenotypically plastic species, for which the oldest available names are respectivelyT. capensis andT. bicarinata. Despite the resultant reduction in number of recognized species, the phasianellid fauna of southern Africa remains the most diverse in the world, with 10 endemic species and 3 tropical species extending south into KwaZulu-Natal.

Molecular phylogenetics of eimeriid coccidia (Eimeriidae, Eimeriorina, Apicomplexa, Alveolata): A preliminary multi-gene and multi-genome approach.

Coccidia possess three distinct genomes: nuclear, mitochondrial, and plastid. Sequences from five genes located on these three genomes were used to reconstruct the phylogenetic relationships of members of the phylum Apicomplexa: 18S rDNA sequences from the nuclear (nu) genome, partial cytochrome c oxidase subunit I sequences from the mitochondrial (mt) genome, and partial 16S and 23S rDNA sequences and RNA polymerase B sequences from plastid (pl) genomes. Maximum parsimony, maximum likelihood, and Bayesian inference were used in conjunction with nuclear substitution models generated from data subsets in the analyses. Major groups within the Apicomplexa were well supported with the mitochondrial, nuclear, and a combination of mitochondrial, nuclear and concatenated plastid gene sequences. However, the genus Eimeria was paraphyletic in phylogenetic trees based on the nuclear gene. Analyses using the individual genes (18S rDNA and cytochrome c oxidase subunit I) resolved the various apicomplexan groups with high Bayesian posterior probabilities. The multi-gene, multi-genome analyses based on concatenated nu 18S rDNA, pl 16S, pl 23S, pl rPoB, pl rPoB1, and mt COI sequences appeared useful in resolving phylogenetic relationships within the phylum Apicomplexa. Genus-level relationships, or higher, appear best supported by 18S rDNA analyses, and species-level analyses are best investigated using mt COI sequences; for parasites for which both loci are available, nuclear 18S rDNA sequences combined with mitochondrial COI sequences provide a compact and informative molecular dataset for inferring the evolutionary relationships taxa in the Apicomplexa.

Phylogenetic relationships of two freshwater pearl mussels, Margaritifera laevis (Haas, 1910) and Margaritifera togakushiensis Kondo & Kobayashi, 2005 (Bivalvia: Margaritiferidae), in the Japanese archipelago

The phylogenetic relationship between Margaritifera togakushiensis Kondo & Kobayashi, 2005, a newly recognised species distributed in the Japanese archipelago, and its closely related species, M. laevis (Haas, 1910) widely distributed in the same area, was analysed based on the mitochondrial COI and nuclear ribosomal (18S rRNA, 28S rRNA) gene sequences. The sequence data of several margaritiferids registered in GenBank were also used in the analysis. Margaritifera togakushiensis and the North American species M. marrianae were the most closely related species, forming a clade with which the Japanese M. laevis and the North American M. falcata were sisters. The two Japanese and two North American margaritiferid species, which occur on opposite sides of the Pacific Ocean, form the newest lineage in the Margaritiferidae, a family thought to be the most primitive of the freshwater pearl mussels, originating in the Mesozoic. Our results also support recent suggestions that generic names Dahurinaia and Cumberlandia be combined into the genus Margaritifera. Based on our sequence and shell morphology data, we confirmed that Russian samples previously assigned as M. laevis were actually M. togakushiensis. Most margaritiferid species worldwide, not only those in Japan, are in a critical situation at present. It is important that these freshwater mussels and their host fishes, which have great evolutionary and ecological interest, be conserved into the future.

Regional differentiation and extensive hybridization between mitochondrial clades of the Southern Ocean giant sea spider Colossendeis megalonyx.

Assessing the enormous diversity of Southern Ocean benthic species and their evolutionary histories is a central task in the era of global climate change. Based on mitochondrial markers, it was recently suggested that the circumpolar giant sea spider Colossendeis megalonyx comprises a complex of at least six cryptic species with mostly small and non-overlapping distribution ranges. Here, we expand the sampling to include over 500 mitochondrial COI sequences of specimens from around the Antarctic. Using multiple species delimitation approaches, the number of distinct mitochondrial OTUs increased from six to 15–20 with our larger dataset. In contrast to earlier studies, many of these clades show almost circumpolar distributions. Additionally, analysis of the nuclear internal transcribed spacer region for a subset of these specimens showed incongruence between nuclear and mitochondrial results. These mito-nuclear discordances suggest that several of the divergent mitochondrial lineages can hybridize and should not be interpreted as cryptic species. Our results suggest survival of C. megalonyx during Pleistocene glaciations in multiple refugia, some of them probably located on the Antarctic shelf, and emphasize the importance of multi-gene datasets to detect the presence of cryptic species, rather than their inference based on mitochondrial data alone.

Two new species of Dracoderes (Kinorhyncha: Dracoderidae) from the Ryukyu Islands, Japan, with a molecular phylogeny of the genus.

Two new species, Dracoderes snufkini sp. nov. and Dracoderes toyoshioae sp. nov., are described from Okinawa, southern Japan. Diagnostic characters of D. snufkini include: lateroventral tubules on segments 2 and 5; a thick, plump middorsal spine on segments 2 and 9; thick plump paradorsal spines on segments 3-8, alternately laterally displaced; and a ventral primary pectinate fringe on segment 1, with long, wide conspicuous tips. Diagnostic characters of Dracoderes toyoshioae include: a middorsal subcuticular structure on segment 1; paradorsal subcuticular structures on segments 2-9, alternately laterally displaced; paradorsal acicular spines arising from subcuticular structures, at least on segment 5; ventrolateral acicular spines on segment 1; lateral accessory tubules on segment 2; lateral accessory subcuticular structures on segments 2-7; lateroventral tubules on segment 5; and lateroventral subcuticular structures on segments 2-10. Molecular phylogenetic analyses based on 18S rRNA, 28S rRNA and mitochondrial COI sequences indicate that D. abei and D. nidhug are more closely related to one another than either is to D. snufkini or D. toyoshioae.

Intra‐specific variations in reaction norms of predator‐induced polyphenism in the water flea Daphnia pulex

AbstractPhenotypic plasticity is considered an important factor leading to phenotypic evolution through adaptations to changing environments. Interactions between environmental inputs and expressed phenotypes can be evaluated as “reaction norms”. Comparisons of these reaction norms among geographically distinct populations may provide evidence for genetic diversity and, moreover, important clues into understanding how the interactions affect evolutionary processes. The water flea Daphnia pulex exhibits predator‐induced polyphenism in response to a kairomone released by predatory phantom midge larvae (Chaoborus spp.). The polyphenism, a defensive structure formed on the head that enables juvenile larvae to avoid predation, is referred to as neckteeth. Differences in shape and/or plasticity of defensive structures have also been reported among related Daphnia species, suggesting that the species‐specific variation in defensive morphology is derived from intra‐specific differences in reaction norms. By determining reaction norms based on the incidence and number of neckteeth, we clarified differences in patterns of neckteeth formation in response to varying concentrations of Chaoborus kairomone. We then compared these differences among populations (strains) collected from six locations in Japan. Our findings showed that the reaction norms of both traits differed among strains. Furthermore, a molecular phylogeny using mitochondrial ND5 and COI sequences suggested that differences in the reaction norms of Japanese strains corresponded to their genetically different lineages, which likely originated from North American populations that were probably introduced to Japan independently.

Species composition and abundance of copepods in the morphologically cryptic genus Pseudocalanus in the Bering Sea

Copepods in the genus Pseudocalanus are abundant in temperate-boreal waters of the Northern Hemisphere. However, their relative distributions are not well known because many species are morphologically cryptic. Here, Pseudocalanus species abundance and distribution in the southeastern Bering Sea from March to June, 2010, were determined using samples spanning the middle (50–100m depth) and outer (>100m depth) shelf domains. Based on analysis of mitochondrial COI sequences of 637 adult females, four species were identified; two are temperate (Pseudocalanus mimus, Pseudocalanus newmani) and two arctic (Pseudocalanus minutus, Pseudocalanus acuspes). Average genetic divergence among species was 14.7±4%. Species abundance and distribution differed significantly between the outer and middle shelf domains. For example, the temperate species P. mimus was more abundant in the outer shelf domain of the SE Bering Sea, while the arctic species P. acuspes was more abundant in the middle shelf domain. Genetic diversity within species varied. Haplotype and nucleotide diversities were higher in temperate than arctic species. No genetic structure was observed in the temperate species P. newmani or the arctic P. minutus across the outer and middle shelf domains, suggesting high levels of gene flow and connectivity across the shelf. Differences in the abundance, distribution and genetics among Pseudocalanus species in the Bering Sea highlight their unique ecological dynamics and evolutionary histories and suggest that they may have distinct responses to future environmental change.

Aphis pomi and Aphis spiraecola (Hemiptera: Sternorrhyncha: Aphididae) in Europe - new information on their distribution, molecular and morphological peculiarities

Aphid species Aphis pomi (de Geer, 1773) is oligophagous on pomoideous host plants, whilst Aphis spiraecola Patch, 1914 is a polyphagous species alternating between Spiraea spp., its primary host, and a wide variety of secondary hosts, also including pomoideous species. Despite the biological distinction, these species are difficult to separate using their morphological characters. Partial sequences of mitochondrial COI and nuclear EF-1&alpha; genes were analyzed for samples from Central and Eastern Europe, Germany, Bulgaria, Italy, Turkey, China together with available data from GenBank. Interspecific pairwise sample divergences of the COI fragment ranged from 3.1 to 4.3%. One COI haplotype of A. pomi was predominant (n = 24), with a pan European distribution. The most abundant COI haplotype of A. spiraecola (n = 16) occurred in Lithuania, Latvia, Poland, Italy, Turkey and China. Interspecific pairwise sample divergences of the EF-1&alpha; fragment ranged from 0.6 to 1.2%. Analyzed partial sequences of EF-1&alpha; were identical in A. pomi. The most abundant EF-1&alpha; haplotype of A. spiraecola (n = 14) occurred in Lithuania, Poland, Italy, Turkey and China. The length of ultimate rostral segment appeared to be the most reliable morphological character for discrimination between apple and spirea aphid species. It allowed a 100% correct identification of A. pomi (n = 143) and 91.5% of A. spiraecola (n = 94) specimens in the European samples used for the molecular analysis. The existence of A. spiraecola in the Eastern Baltic region of Europe is documented for the first time.

Differences in population connectivity of a benthic marine invertebrate Evechinus chloroticus (Echinodermata: Echinoidea) across large and small spatial scales

Marine organisms with a planktonic larval stage have the potential to be transported substantial distances, with the distance travelled depending on factors such as pelagic larval duration (PLD) and physical factors such as ocean currents and geographical barriers. The endemic New Zealand sea urchin, Evechinus chloroticus, is found throughout the North and South Islands, and with a PLD of approximately 30 days, is expected to show strong connectivity among all populations. Population connectivity and genetic differentiation were examined over both a geographically broad scale, throughout New Zealand, and on a fine scale (within the Hauraki Gulf on the North Island). Significant genetic differentiation was revealed through analysis of mitochondrial COI sequences (FST = 0.096 p < 0.01) and six microsatellite loci (FST = 0.0120 p < 0.008). This was consistent with a division between northern and southern regions located to the south of Cook Strait, at a phylogeographic barrier previously reported in other New Zealand benthic marine invertebrates. Fine-scale population differentiation was evident between the inner and outer Hauraki Gulf populations, and between the most northern populations and the remainder of the North Island. Together, this study suggests that strong coastal currents, upwelling in the Cook Strait region, and geographic distance (approximately 2000 km north to south) may all be acting to restrict gene flow and contribute to genetic divergence among populations of E. chloroticus.