Redescription of the Antarctic springtail Desoria klovstadi using morphological and molecular evidence

Isotoma klovstadi Carpenter, 1902 was one of the first Collembola described from the Antarctic continent. It was first collected in November 1899 during the British Antarctic Expedition on the north coast of Victoria Land in the Ross Sea region. It is now known to occur in an extensive area of northern Victoria Land, including the offshore Possession, Coulman, and Foyn Islands. More recently, I. klovstadi was moved to the genus Gnathisotoma Cassagnau, 1957 and has been included in this genus in an unpublished checklist (online) of all described Collembola. Here, we redescribe the species and use morphological and molecular (COI and 18S genes) evidence to investigate its affinities within the Isotominae. We show that it does not belong to Gnathisotoma, or Isotoma s. str. (the viridis group) as currently conceived, but is likely to be part of the species complex of Isotoma s. lat. We discuss reasons for placing it in the genus Desoria Nicolet, 1841. Our results reinforce the already high level of endemicity in the Antarctic fauna and emphasise the value of both morphological and molecular studies in examining relict Gondwanan taxa and their evolutionary relationships with those of other Southern Hemisphere continents.     

Phylogeny of Bonatea (Orchidaceae: Habenariinae) based on molecular and morphological data

The genus Bonatea is widely distributed throughout southern and eastern Africa. Considerable debate surrounds the generic status of Bonatea, but there have been neither previous studies of evolutionary relationships among Bonatea species, nor any tests of the monophyly of the genus in relation to its close relative Habenaria. We investigated phylogenetic relationships between Bonatea and selected Habenaria species using morphology, as well as sequences of the chloroplast gene matK and the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA. A fully resolved cladogram was obtained using morphological data, but neither the ITS, matK, nor combined data sets yielded well-resolved and well-supported phylogenetic structure for Bonatea. There is poor congruence between ITS and matK data for interspecific relationships in Bonatea, whilst the morphological results are largely congruent with the ITS analysis. Relative to Habenaria, there is little sequence variation between Bonatea species, which could indicate a recent and rapid radiation of Bonatea. Although the sampled Bonatea species form a distinct clade, more extensive sampling of Habenaria would be required to establish unambiguously whether or not Bonatea is monophyletic.     

Morphological and molecular description of new species of squat lobster (Crustacea: Decapoda: Galatheidae) from the Solomon and Fiji Islands (South‐West Pacific)

The family Galatheidae is among the most diverse families of anomuran decapod crustaceans, and the South‐West Pacific is a biodiversity hot spot for these squat lobsters. Attempts to clarify the taxonomic and evolutionary relationships of the Galatheidae on the basis of morphological and molecular data have revealed the existence of several cryptic species, differentiated only by subtle morphological characters. Despite these efforts, however, relationships among genera are poorly understood, and the family is in need of a detailed systematic review. In this study, we assess material collected in different surveys conducted in the Solomon Islands, as well as comparative material from the Fiji Islands, by examining both the morphology of the specimens and two mitochondrial markers (cytochrome oxidase subunit I, COI, and 16S rRNA). These two sources of data revealed the existence of eight new species of squat lobster, four of which were ascribed to the genus Munida, two to the genus Paramunida, one to the genus Plesionida, and the last species was ascribed to the genus Agononida. These eight species are described along with phylogenetic relationships at the genus level. Our findings support the taxonomic status of the new species, yet the phylogenetic relationships are not yet fully resolved. Further molecular analysis of a larger data set of species, and more conserved genes, will help clarify the systematics of this group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 465–493.     

Molecular phylogeny of Glossodoris (Ehrenberg, 1831) nudibranchs and related genera reveals cryptic and pseudocryptic species complexes

Chromodorid nudibranchs (Chromodorididae) are brightly coloured sea slugs that live in some of the most biodiverse and threatened coral reefs on the planet. However, the evolutionary relationships within this family have not been well understood, especially in the genus Glossodoris. Members of Glossodoris have experienced large‐scale taxonomic instability over the last century and have been the subject of repeated taxonomic changes, in part due to morphological characters being the sole traditional taxonomic sources of data. Changing concepts of traditional generic boundaries based on morphology also have contributed to this instability. Despite recent advances in molecular systematics, many aspects of chromodorid taxonomy remain poorly understood, particularly at the traditional species and generic levels. In this study, 77 individuals comprising 32 previously defined species were used to build the most robust phylogenetic tree of Glossodoris and related genera using mitochondrial genes cytochrome c oxidase subunit I and 16S, and the nuclear gene 28S. Bayesian inference, maximum likelihood, and maximum parsimony analyses verify the most recent hypothesized evolutionary relationships within Glossodoris. Additionally, a pseudocryptic and cryptic species complex within Glossodoris cincta and a pseudocryptic complex within Glossodoris pallida emerged, and three new species of Doriprismatica are identified.     

Phylogeny,evolutionary morphology,and hemipenis descriptions of the Middle American jumping pitvipers (Serpentes: Crotalinae: Atropoides)

The jumping pitvipers, genus Atropoides, occur at low to middle elevations throughout Middle America. Recent molecular phylogenetic analyses have included all six species of Atropoides, but only two studies have found Atropoides to be monophyletic and questions persist about relationships within the A. nummifer complex. In this study, our phylogenetic analyses of morphological data provide strong support for the monophyly of Atropoides and recover relationships within the genus that are mostly congruent with those of recent molecular studies, further supporting the evolutionary and biogeographic hypotheses proposed in those studies. Our analyses find support for a sister relationship between A. picadoi and the other Atropoides species and an A. occiduus–A. indomitus clade sister to an A. nummifer–A. mexicanus–A. olmec clade. Within the A. nummifer complex, we find A. mexicanus and A. olmec to be sister species to the exclusion of A. nummifer. We include morphological synapomorphies to support each clade within Atropoides and describe and illustrate the hemipenes of each species. In addition, we discuss the importance of morphological phylogenetics and the functionality and limitations of hemipenial data in systematics.     

Phylogenetic relationships of North American Gomphidae and their close relatives

Intrafamilial relationships among clubtail dragonflies (Gomphidae) have been the subject of many morphological studies, but have not yet been systematically evaluated using molecular data. Here we present the first molecular phylogeny of Gomphidae. We include six of the eight subfamilies previously suggested to be valid, and evaluate generic relationships within them. We have included examples of all genera reported from the Nearctic except Phyllocycla. This sample includes all North American species of Ophiogomphus, which has allowed us to explore intrageneric relationships in that genus. Our particular focus is on the closest relatives of the genus Gomphus, especially those North American species groups that have been commonly treated as subgenera of Gomphus. The Gomphus complex is split into additional genera, supported by molecular and morphological evidence: Phanogomphus, Stenogomphurus, Gomphurus and Hylogomphus are here considered to be valid genera. The genus Gomphus, in our restricted sense, does not occur in the western hemisphere; in addition, G. flavipes is transferred to Stylurus.     

Phylogenetic Relationships of the Prodontria (Coleoptera; Scarabaeidae; Subfamily Melolonthinae), Derived from Sequence Variation in the Mitochondrial Cytochrome Oxidase II Gene

The beetle genus Prodontria is of importance to New Zealand conservation programs. All Prodontria species are brachypterous (having reduced wings), and the genus presents some interesting evolutionary and biogeographic questions that are testable using phylogenetic reconstruction. A phylogeny was produced for 14 flightless Prodontria species, 2 macropterous (fully winged) Odontria species, and single representatives of 2 outgroup genera using sequence data from the mitochondrial COII gene. The data support probable conspecificity of the morphologically similar P. modesta and P. bicolorata but do not support their hypothesized sister-species relationship with the geographically proximate P. lewisi. The alpine P. capito is found to be a paraphyletic group, with the most eastern population diverging after the western populations made their appearance. Many interesting biogeographic disjunctions are here proposed to be anomalous and the result of morphological convergence. The data do not support the idea of a common flightless ancester for Prodontria, but suggest that brachyptery has evolved numerous times. In some instances, this appears to have led to contemporaneous speciation resulting in little resolution of phylogenetic relationships in some parts of the tree. These data allow for a new interpretation of the origin and diversification of the southern New Zealand flightless melolonthine fauna. Multiple speciation events involving wing reduction are suggested to involve at least one widespread flighted ancestor that has given rise to brachypterous forms.     

Evolutionary geographic relationships among orthocladine chironomid midges from maritime Antarctic and sub‐Antarctic islands

Two species of chironomid midges are currently described in the genus Belgica Jacobs, 1900. Belgica antarctica Jacobs, 1900 is endemic to parts of the maritime Antarctic, and Belgica albipes (Séguy, 1965) is endemic to Îles Crozet, a sub‐Antarctic archipelago in the southern Indian Ocean. The relationships between these species, and their closest known relative (Eretmoptera murphyi Schaeffer, 1914, endemic to sub‐Antarctic South Georgia), were examined by sequencing DNA fragments for domains 1 and 3–5 of 28S ribosomal DNA and the mitochondrial gene cytochrome c oxidase 1 (cox1). The resulting molecular relationships between the three species were unclear, although their position within the subfamily Orthocladiinae of the Chironomidae, as generated by classical taxonomy, was confirmed. Our data reinforce earlier doubts, based on classical morphological approaches, that the generic placement of E. murphyi may be incorrect. Further analyses may indeed confirm that the species represents a third member of the genus Belgica. Genetic distance analysis, limited to the barcode region of cox1, indicated high differentiation between the two populations of B. albipes sampled (one obtained from the type location), suggesting the likely presence of cryptic species within this taxon, and that the taxonomic status of this species should be revised. Analysis of cox1 sequences in B. antarctica highlighted a strong genetic structure between populations obtained from 12 locations along the Antarctic Peninsula and the South Shetland Islands archipelago, with a number of distinctive mtDNA lineages inhabiting geographically distinct areas. In particular, we found four different haplogroups constituting geographically close but genetically distinct populations, a pattern likely to have been encouraged by the brachyptery of the members of this genus. We suggest that the different genetic patterns shown by each haplogroup have probably been determined by historical dispersal and colonization events during the Pleistocene, and are consistent with their survival in refuges in situ during successive glacial maxima over this period. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106 , 258–274.     

A new species of <Emphasis Type="Italic">Pareledone</Emphasis> (Cephalopoda: Octopodidae) from Antarctic Peninsula Waters

During recent cruises aboard RV Polarstern in the Antarctic Peninsula region, a new species of benthic octopodid was discovered whose generic affinities based on morphological characteristics were uncertain. Molecular sequence analysis of six mitochondrial and nuclear genes allows this species to be placed with confidence within the genus Pareledone. The species is described herein and morphological diagnostic characters are provided for its identification.     

Is reproductive strategy a key factor in understanding the evolutionary history of Southern Ocean Asteroidea (Echinodermata)?

Life traits such as reproductive strategy can be determining factors of species evolutionary history and explain the resulting diversity patterns. This can be investigated using phylogeographic analyses of genetic units. In this work, the genetic structure of five asteroid genera with contrasting reproductive strategies (brooding: Diplasterias, Notasterias and Lysasterias versus broadcasting: Psilaster and Bathybiaster) was investigated in the Southern Ocean. Over 1,400 mtDNA cytochrome C oxidase subunit I (COI) sequences were analysed using five species delineation methods (ABGD, ASAP, mPTP, sGMYC and mGMYC), two phylogenetic reconstructions (ML and BA), and molecular clock calibrations, in order to examine the weight of reproductive strategy in the observed differences among phylogeographic patterns. We hypothesised that brooding species would show higher levels of genetic diversity and species richness along with a clearer geographic structuring than broadcasting species. In contrast, genetic diversity and species richness were not found to be significantly different between brooders and broadcasters, but broadcasters are less spatially structured than brooders supporting our initial hypothesis and suggesting more complex evolutionary histories associated to this reproductive strategy. Broadcasters' phylogeography can be explained by different scenarios including deep‐sea colonisation routes, bipolarity or cosmopolitanism, and sub‐Antarctic emergence for the genus Bathybiaster; Antarctic‐ New Zealand faunal exchanges across the Polar Front for the genus Psilaster. Brooders' phylogeography could support the previously formulated hypothesis of a past trans‐Antarctic seaway established between the Ross and the Weddell seas during the Plio‐Pleistocene. Our results also show, for the first time, that the Weddell Sea is populated by a mixed asteroid fauna originating from both the East and West Antarctic.     

Molecular phylogeny and morphological analysis resolve a long‐standing controversy over generic concepts in Ecdyonurinae mayflies (Ephemeroptera: Heptageniidae)

Heptageniidae is a species‐rich mayfly family (Ephemeroptera), whose taxonomy and phylogeny have been based almost exclusively on traditional morphological studies. Inconsistent use of diagnostic characters and the general lack of molecular studies have led to vague generic concepts, and the phylogenetic relationships among taxa in the family remain unclear. Afronurus Lestage is an Old World heptageniid genus of 66 species. The generic assignment of two species within this genus, A. kugleri Demoulin and A. zebratus (Hagen), has been the subject of much debate, because they share many apomorphic features that distinguish them from other congeners. We combined a thorough morphological study of all life stages of 28 representative heptageniid species with a molecular phylogenetic analysis of four mitochondrial and nuclear markers to resolve the generic position of A. kugleri and A. zebratus as well as the integrity of Afronurus and related genera. Our results confirm the monophyly of Afronurus and Electrogena and support the assignment of A. kugleri and A. zebratus to a newly described genus, Anapos Yanai & Sartori gen.n . We provide clear, diagnostic morphological characters for the genus and discuss the need for a thorough revision of generic concepts in the subfamily Ecdyonurinae. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:075E40C6-BAFE-4184-A2C2-E3BCFBC0BC15 .     

The new Arctic side-gilled sea slug genus <Emphasis Type="Italic">Boreoberthella</Emphasis> (Gastropoda,Opisthobranchia): Pleurobranchoidean systematics and evolution revisited

Most of the ca. 100 known pleurobranchoid side gilled sea slug species are confined to temperate and warm coastal waters worldwide. Exceptions were five enigmatic Antarctic and southern deep sea species. Herein the first Arctic deep water pleurobranchid, Boreoberthella augusta gen. et spec. nov., is anatomically described. To reveal the origin, relationships and phylogeography of Boreoberthella, a cladistic analysis of 24 pleurobranchoid taxa representing all genera and traditional higher groups was prepared. The morphological data set includes 72 characters; many of them, such as details of the copulatory apparatus, were explored for the first time. The monophyly of both Pleurobranchoidea and Pleurobranchaeidae is confirmed. In contrast to an earlier study, the southern Ocean deep-water species Tomthompsonia antarctica results as basal offshoot of the monophyletic though poorly supported Pleurobranchidae which show a secondary, internal shell. The traditional genus Berthella with worldwide temperate and tropical members may represent an evolutionary grade rather than a clade. The monotypic genera Parabathyberthella and Polictenidia are synonymized with Bathyberthella according to taxonomic and phylogenetic evidence. The basal pleurobranchaeid genus Pleurobranchella, together with Tomthompsonia, Bathyberthella, and Boreoberthella are discussed as potential relics of a cold-water related early nudipleuran radiation in Antarctica, with subsequent dispersal through the depths of the world oceans. The ancestor of Pleurobranchus species, the closest relatives of Boreoberthella, colonized coastal and warmer waters and radiated there.     

Phylogeny of Dendroctonus bark beetles (Coleoptera: Curculionidae: Scolytinae) inferred from morphological and molecular data

Bark beetles in the genus Dendroctonus may attack and kill several species of coniferous trees, some of them causing major economic losses in temperate forests throughout North and Central America. For this reason, they have been widely studied. However, various aspects of the taxonomy and evolutionary history of the group remain contentious. The genus has been subdivided in species groups according to morphological, biological, karyological or molecular attributes, but the evolutionary affinities among species and species groups within the genus remain uncertain. In this study, phylogenetic relationships among Dendroctonus species were reassessed through parsimony‐based cladistic analysis of morphological and DNA sequence data. Phylogenetic inference was based on 36 morphological characters and on mitochondrial DNA sequences of the cytochrome oxidase I (COI) gene. Analyses were carried out for each dataset, as well as for the combined data analysed simultaneously, under equal and implied weights. According to the combined analysis, the genus Dendroctonus is a monophyletic group defined by at least three synapomorphic characters and there are four main lineages of varied composition and diversity within the genus. Within these lineages, several monophyletic groups match, to some extent, species groups defined by previous authors, but certain groups proposed by those authors are polyphyletic or paraphyletic.     

Molecules,morphology and minute hooded beetles: a phylogenetic study with implications for the evolution and classification of Corylophidae (Coleoptera: Cucujoidea)

Eight genes (nuclear: 18S, 28S, H3, CAD; mitochondrial: 12S, 16S, COI, COII) and morphology were used to infer the evolutionary history of Corylophidae, some of the smallest free‐living insects. The study included 36 corylophid exemplars, representing approximately 60% of the known generic diversity of the family and 16 cucujoid outgroup taxa. Multiple partitioning strategies, molecular datasets, combined datasets and different taxon sampling regimes using maximum likelihood and mixed‐model Bayesian inference were utilized to analyse these data. Most results were highly concordant across analyses. There was strong agreement across (i) partitioning strategies, (ii) maximum likelihood and Bayesian inference analyses of the molecular data, and (iii) Bayesian inference of the molecular data alone and Bayesian inference of the combined morphological and molecular data when all terminal taxa were included. When a strict taxon sampling protocol was employed so that only single generic exemplars were included, deep relationships were affected in the resulting phylogenetic hypotheses. Under such narrow sampling strategies, deep phylogenetic relationships were also sensitive to the choice of generic exemplars. Although it is often challenging to obtain single representatives for many taxa in higher‐level phylogenetic analyses, these results indicate the importance of using denser taxon sampling approaches even at the specific level for genera included in such studies. Molecular data alone support Anamorphinae (Endomychidae) strongly as the sister group of Corylophidae. In combined data analyses, Coccinellidae is recovered as the sister group to Corylophidae. In all analyses, Corylophidae and the subfamily Corylophinae are recovered as monophyletic. The monophyly of Periptyctinae was untested, as only a single species was included. All included corylophine tribes were recovered as monophyletic with the exception of Aenigmaticini; Aenigmaticum Matthews forms the sister group to Orthoperus Stephens and Stanus?lipiński et al. is recovered as the sister group of Sericoderus Stephens. Stanus tasmanicus?lipiński et al. is transferred to a new genus, Pseudostanus Robertson, ?lipiński & McHugh gen.n. incertae sedis. We propose a new tribe, Stanini Robertson, ?lipiński & McHugh trib.n. for Stanus bowesteadi?lipiński et al. and a new concept of Aenigmaticini sensu.n. to include only the nominate genus. Anatomical transitions associated with corylophid miniaturization are highlighted. Key phenotypic modifications and elevated rates of substitution in nuclear rRNA genes are evident in a subgroup of Corylophinae that includes the most diminutive species. Other taxonomic and evolutionary implications are discussed in light of the results.     

Species delimitation in the Andean grasshopper genus Orotettix Ronderos & Carbonell (Orthoptera: Melanoplinae): an integrative approach combining morphological,molecular and biogeographical data

The reciprocal illumination nature of integrative taxonomy through hypothesis testing, corroboration and revision is a powerful tool for species delimitation as more than one source has to support the hypothesis of a new species. In this study, we applied an integrative taxonomy approach combining molecular and morphological data sets with distributional patterns to examine the level of differentiation between and within the grasshopper Orotettix species. Orotettix was described based on five valid species distributed in the Andes of Peru. In our study, initially a molecular‐based hypothesis was postulated and tested against morphological data and geographical patterns of distribution. Results from molecular and morphological analyses showed agreement among the species delimitation in Orotettix, and were also consistent with the geographical distribution. The analyses allowed us to delimit five new species for the genus ( O. lunatus sp. nov. , O . astreptos sp. nov. , O. colcaensis sp. nov. , O . paucartambensis sp. nov. and O . dichrous sp. nov. ) from the Eastern and Western Cordilleras of Peru. We also provide critical knowledge on the phylogenetic relationships and distribution of the genus and conduct a revision of Orotettix. © 2015 The Linnean Society of London