Southern Hemisphere Clade Research Articles

Plastid genome data provide new insights into the dynamic evolution of the tribe Ampelopsideae (Vitaceae)

BackgroundAmpelopsideae J. Wen & Z.L. Nie is a small-sized tribe of Vitaceae Juss., including ca. 47 species from four genera showing a disjunct distribution worldwide across all the continents except Antarctica. There are numerous species from the tribe that are commonly used as medicinal plants with immune-modulating, antimicrobial, and anti-hypertensive properties. The tribe is usually recognized into three clades, i.e., Ampelopsis Michx., Nekemias Raf., and the Southern Hemisphere clade. However, the relationships of the three clades differ greatly between the nuclear and the plastid topologies. There has been limited exploration of the chloroplast phylogenetic relationships within Ampelopsideae, and studies on the chloroplast genome structure of this tribe are only available for a few individuals. In this study, we aimed to investigate the evolutionary characteristics of plastid genomes of the tribe, including their genome structure and evolutionary insights.ResultsWe sequenced, assembled, and annotated plastid genomes of 36 species from the tribe and related taxa in the family. Three main clades were recognized within Ampelopsideae, corresponding to Ampelopsis, Nekemias, and the Southern Hemisphere lineage, respectively, and all with 100% bootstrap supports. The genome sequences and content of the tribe are highly conserved. However, comparative analyses suggested that the plastomes of Nekemias demonstrate a contraction in the large single copy region and an expansion in the inverted repeat region, and possess a high number of forward and palindromic repeat sequences distinct from both Ampelopsis and the Southern Hemisphere taxa.ConclusionsOur results highlighted plastome variations in genome length, expansion or contraction of the inverted repeat region, codon usage bias, and repeat sequences, are corresponding to the three lineages of the tribe, which probably faced with different environmental selection pressures and evolutionary history. This study provides valuable insights into understanding the evolutionary patterns of plastid genomes within the Ampelopsideae of Vitaceae.

Molecular Phylogeny of Dermestidae (Coleoptera) Reveals the Polyphyletic Nature ofTrogodermaLatreille and the Taxonomic Placement of the Khapra BeetleTrogoderma granariumEverts

AbstractThe hide, larder, and carpet beetles (Coleoptera: Dermestidae) are a family of mainly scavenger beetles, with numerous species such as the khapra beetle (Trogoderma granarium Everts, 1898), the black carpet beetle [Attagenus unicolor (Brahm, 1791)] and the hide beetle (Dermestes maculatus De Geer, 1774) being widely recognized as serious economic pests of stored products and museum collections. A stable classification and reliable identification of genera and species of these pests and their 1,700 relatives are of great relevance for trade restrictions, biosecurity, pest management, forensics, and biodiversity surveys. In this study, we examined and sequenced mitochondrial genomes of 477 dermestid specimens, representing all subfamilies and 90% of the globally recognized tribes and subtribes. Our study provides the most comprehensive, taxonomically verified, and vouchered resource of mitochondrial reference sequences linked to specimen images and occurrence records of pests and their relatives, enabling eDNA surveys, metabarcoding and molecular species identification. It also reconstructs the phylogeny of Dermestidae based on molecular and morphological data for the first time, thereby providing robust phylogenetic hypotheses for a stable classification system from family to genus-level. Accordingly, a revised classification of Dermestidae with formal nomenclatural changes is proposed, recognizing six subfamilies: Orphilinae, Trinodinae, Trogoparvinae subfam. nov. (type genus TrogoparvusHáva, 2001), Dermestinae, Attageninae, and Megatominae. Trinodinae is recovered towards the base of Dermestidae with three tribes: Trinodini (=Trinoparvini syn. nov.), Thylodriini, and Trichelodini. Dermestinae is the only subfamily with adults lacking a median ocellus, and it includes the tribes Thorictini stat. nov. (that is downgraded from Thorictinae), Marioutini, and Dermestini. The endemic Australian genus Derbyana Lawrence and Ślipiński was recovered within Holarctic Dermestes Linnaeus. Attageninae is strongly supported and includes the monogeneric Adelaidiini and polygenic Attagenini. Former subgenera of Attagenus Latreille, i.e., Lanorus Mulsant and Rey (= Paranovelsis Casey syn. nov.), Telopes Redtenbacher and Aethriostoma Motschulsky, are elevated to generic level. The largest clade, Megatominae, is confirmed as monophyletic and is divided into three tribes: Anthrenini, Ctesiini, and Megatomini. Megatomini is divided into three subtribes: Megatomina, Orphinina subtribe nov. (type genus Orphinus Motschulsky), and Trogodermina. Within the economically important lineage Trogodermina, Trogoderma Latreille is delimited to contain only Holarctic species including the Khapra beetle T. granarium Everts, while a Southern Hemisphere clade is here recognized as Eurhopalus Solier in Gay, 1849 (= AnthrenocerusArrow, 1915; Myrmeanthrenus Armstrong, 1945; Neoanthrenus Armstrong, 1941; SodaliatomaHáva, 2013; Reesa Beal, 1967 syn. nov.). A revised classification of the extant genera of Dermestidae is also provided.

Phylogeny and Biogeography of Acaena (Rosaceae) and its Relatives: Evidence of Multiple Long-Distance Dispersal Events Across the Globe

Abstract— Acaena (Rosaceae) is the most complex and ecologically variable genus in Sanguisorbinae. Although it has been the subject of several taxonomic treatments, the largest phylogenetic analysis to date only sampled a small fraction of the total global diversity (five to seven out of 45 to 50 species). This study included most of the species to elucidate the phylogenetic relationships of Acaena and biogeographic patterns in Sanguisorbinae. Phylogenetic analyses of non-coding nuclear (ITS region) and chloroplast (trnL-F) DNA sequence markers using maximum likelihood and Bayesian analyses suggested that Acaena is a paraphyletic group with species of Margyricarpus and Tetraglochin nested within it. We identified strong support for eight subclades that are geographically or taxonomically structured. Nevertheless, the species-level relationships within subclades are still uncertain, which may be due to rapid diversification and lack of informative characters in the markers used. Sanguisorbinae, a primarily Southern Hemisphere clade, exhibits a classic Gondwana disjunct distribution. This current distribution is explained primarily by eight long-distance dispersal events. Our results suggested that Sanguisorbinae split into Cliffortia and Acaena around 13.6 mya. While Cliffortia diversified in southern South Africa, Acaena experienced several migration events in the Southern Hemisphere. Our estimation of the ancestral range suggested that Acaena likely originated in South Africa, followed by migration and subsequent diversification into southern South America. From there, the genus migrated to New Zealand, throughout the Andes, and to tropical areas in Central America, reaching as far north as California. Chile and New Zealand are the main sources of propagules for dispersal as well as the greatest diversity for the genus. The evolutionary relationships of species in Acaena combine a history of rapid diversifications, long-distance dispersals, and genetic variation within some taxa. Further research should be undertaken to clarify the infraspecific classification of A. magellanica.

Sex role similarity and sexual selection predict male and female song elaboration and dimorphism in fairy-wrens.

Historically, bird song complexity was thought to evolve primarily through sexual selection on males; yet, in many species, both sexes sing and selection pressure on both sexes may be broader. Previous research suggests competition for mates and resources during short, synchronous breeding seasons leads to more elaborate male songs at high, temperate latitudes. Furthermore, we expect male–female song structure and elaboration to be more similar at lower, tropical latitudes, where longer breeding seasons and year‐round territoriality yield similar social selection pressures in both sexes. However, studies seldom take both types of selective pressures and sexes into account. We examined song in both sexes in 15 populations of nine‐fairy‐wren species (Maluridae), a Southern Hemisphere clade with female song. We compared song elaboration (in both sexes) and sexual song dimorphism to latitude and life‐history variables tied to sexual and social selection pressures and sex roles. Our results suggest that song elaboration evolved in part due to sexual competition in males: male songs were longer than female songs in populations with low male survival and less male provisioning. Also, female songs evolved independently of male songs: female songs were slower paced than male songs, although only in less synchronously breeding populations. We also found male and female songs were more similar when parental care was more equal and when male survival was high, which provides strong evidence that sex role similarity correlates with male–female song similarity. Contrary to Northern Hemisphere latitudinal patterns, male and female songs were more similar at higher, temperate latitudes. These results suggest that selection on song can be sex specific, with male song elaboration favored in contexts with stronger sexual selection. At the same time, selection pressures associated with sex role similarity appear to favor sex role similarity in song structure.

The Evolutionary History of New Zealand Deschampsia Is Marked by Long-Distance Dispersal, Endemism, and Hybridization.

Simple SummaryThe evolution of the flora of New Zealand has been the subject of many debates, including trans-oceanic dispersal and vicariance. Deschampsia, which is a grass genus distributed in cold–temperate regions of both hemispheres, includes the cosmopolitan D. cespitosa and several endemic species in New Zealand. We applied Restriction Site Associated DNA sequencing, plastid genome, and morphological data to study the evolution of Deschampsia in New Zealand. Native New Zealand D. cespitosa was found in a northern hemisphere clade together with samples of Europe, Canada, Russia, China, Korea, whereas the three endemics were found in a southern hemisphere clade, together with D. antarctica of Argentina and Antarctica. We hypothesize that the endemics diverged from a common ancestor with D. cespitosa in the late Miocene or Pliocene. Hybridization between D. cespitosa and the endemic D. chapmanii was confirmed. Our study qualifies as a model of thorough analyses for a non-model group and provides evidence for the evolutionary history of this widespread genus in New Zealand.The contrasting evolutionary histories of endemic versus related cosmopolitan species provide avenues to understand the spatial drivers and limitations of biodiversity. Here, we investigated the evolutionary history of three New Zealand endemic Deschampsia species, and how they are related to cosmopolitan D. cespitosa. We used RADseq to test species delimitations, infer a dated species tree, and investigate gene flow patterns between the New Zealand endemics and the D. cespitosa populations of New Zealand, Australia and Korea. Whole plastid DNA analysis was performed on a larger worldwide sampling. Morphometrics of selected characters were applied to New Zealand sampling. Our RADseq review of over 55 Mbp showed the endemics as genetically well-defined from each other. Their last common ancestor with D. cespitosa lived during the last ten MY. The New Zealand D. cespitosa appears in a clade with Australian and Korean samples. Whole plastid DNA analysis revealed the endemics as members of a southern hemisphere clade, excluding the extant D. cespitosa of New Zealand. Both data provided strong evidence for hybridization between D. cespitosa and D. chapmanii. Our findings provide evidence for at least two migration events of the genus Deschampsia to New Zealand and hybridization between D. cespitosa and endemic taxa.

Phylogenetic relationships, origin and historical biogeography of the genus Sprattus (Clupeiformes: Clupeidae).

The genus Sprattus comprises five species of marine pelagic fishes distributed worldwide in antitropical, temperate waters. Their distribution suggests an ancient origin during a cold period of the earth’s history. In this study, we evaluated this hypothesis and corroborated the non-monophyly of the genus Sprattus, using a phylogenetic approach based on DNA sequences of five mitochondrial genome regions. Sprattus sprattus is more closely related to members of the genus Clupea than to other Sprattus species. We also investigated the historical biogeography of the genus, with the phylogenetic tree showing two well-supported clades corresponding to the species distribution in each hemisphere. Time-calibrated phylogenetic analyses showed that an ancient divergence between Northern and Southern Hemispheres occurred at 55.8 MYBP, followed by a diversification in the Oligocene epoch in the Northern Hemisphere clade (33.8 MYBP) and a more recent diversification in the Southern Hemisphere clade (34.2 MYBP). Historical biogeography analyses indicated that the most recent common ancestor (MRCA) likely inhabited the Atlantic Ocean in the Southern Hemisphere. These results suggest that the ancestral population of the MRCA diverged in two populations, one was dispersed to the Northern Hemisphere and the other across the Southern Hemisphere. Given that the Eocene was the warmest epoch since the Paleogene, the ancestral populations would have crossed the tropics through deeper cooler waters, as proposed by the isothermal submergence hypothesis. The non-monophyly confirmed for the genus Sprattus indicates that its systematics should be re-evaluated.

Crayfish bio-gastroliths from eastern Australia and the middle Cretaceous distribution of Parastacidae

AbstractFossil crayfish are typically rare, worldwide. In Australia, the strictly Southern Hemisphere clade Parastacidae, while ubiquitous in modern freshwater systems, is known only from sparse fossil occurrences from the Aptian–Albian of Victoria. We expand this record to the Cenomanian of northern New South Wales, where opalized bio-gastroliths (temporary calcium storage bodies found in the foregut of pre-moult crayfish) form a significant proportion of the fauna of the Griman Creek Formation. Crayfish bio-gastroliths are exceedingly rare in the fossil record but here form a remarkable supplementary record for crayfish, whose body and trace fossils are otherwise unknown from the Griman Creek Formation. The new specimens indicate that parastacid crayfish were widespread in eastern Australia by middle Cretaceous time, occupying a variety of freshwater ecosystems from the Australian–Antarctic rift valley in the south, to the near-coastal floodplains surrounding the epeiric Eromanga Sea further to the north.

Addressing the diversity of Xylodon raduloides complex through integrative taxonomy

In this study, the taxonomic diversity of the Xylodon raduloides species complex (Hymenochaetales, Basidiomycota) is examined. Specimens were studied using an integrative taxonomic approach that includes molecular phylogenetic and morphological analyses, and environmental niche comparisons. Four different species were found inside the Xylodon raduloides complex, with a biogeographic distribution pattern bound by geographic regions: Europe, North America, Patagonia, and Australia–New Zealand. Molecular, morphological, and environmental evidences delimit two lineages within this complex: a Northern Hemisphere clade with longer basidiospores and wider ranges in temperature and precipitation tolerance, and a Southern Hemisphere clade with smaller and more spherical basidiospores, and an isothermal and more humid climate preference. The integrative taxonomic approach used in this study demonstrates congruence between data sets and shows how morphological and environmental characteristics contribute to the differentiation of fungal species complexes. By combining various sources of taxonomic information, three new species are described: Xylodon laurentianus, X. novozelandicus, and X. patagonicus.

A new elasmosaurid (sauropterygia, plesiosauria) from the bearpaw shale (late cretaceous, maastrichtian) of montana demonstrates multiple evolutionary reductions of neck length within elasmosauridae

ABSTRACT Plesiosauria is a diverse clade of marine reptiles that have been studied since the early 19th century. However, phylogenetic relationships within the group have been contentious due to limited taxon sampling and a misunderstanding of how ontogeny and interspecific and intraspecific variation affect character states. This is particularly true for elasmosaurids, a Cretaceous clade of long-necked plesiosaurians. In 2010, a new, nearly complete skeleton, MOR 3072, was collected from the Late Cretaceous (Campanian–Maastrichtian) Bearpaw Shale of northeast Montana. The specimen provides detailed morphological information rarely observed within Elasmosauridae, including a complete skull, the anterior 23 cervical vertebrae, a partial dorsal and caudal vertebral column, incomplete pectoral and pelvic girdles, elements of both fore- and hind limbs, ribs, and gastralia. Being early Maastrichtian in age, MOR 3072 is the stratigraphically youngest elasmosaurid known from the Western Interior Seaway and is recognized as a new genus and species, Nakonanectes bradti. We present a description of Nakonanectes bradti and conduct an extended phylogenetic analysis of Elasmosauridae. N. bradti is found to be deeply nested within the clade of large-bodied, long-necked, Western Interior Styxosaurinae. However, MOR 3072 is one of the smallest adult elasmosaurids ever recovered (5.1–5.6 m) and exhibits a reduced neck length compared with other North American elasmosaurids, resulting from a reduction in both centrum length and number of cervical vertebrae (39–42 were originally present). These features are convergent with the Southern Hemisphere clade of short-necked Maastrichtian elasmosaurids, Aristonectinae, and demonstrate multiple origins of short-necked body proportions from longer-necked ancestors within Elasmosauridae. http://zoobank.org/urn:lsid:zoobank.org:pub:85731F4A-EA70-4C9A-B595-792EDBC096C0 SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: Serratos, D. J., P. Druckenmiller, and R. B. J. Benson. 2017. A new elasmosaurid (Sauropterygia, Plesiosauria) from the Bearpaw Shale (Late Cretaceous, Maastrichtian) of Montana demonstrates multiple evolutionary reductions of neck length within Elasmosauridae. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1278608.

Phylogeny of the hyper‐diverse rove beetle subtribe Philonthina with implications for classification of the tribe Staphylinini (Coleoptera: Staphylinidae)

AbstractWith 71 genera and over 2700 described species, Philonthina is the most speciose subtribe of rove beetle tribe Staphylinini and forms a major component of the largest remaining higher systematics challenge in Staphylinini, the ‘Staphylinini propria’ clade. A related systematics issue concerns the position of the genus Holisus (Hyptiomina), which was recovered within the Neotropical philonthine lineage in several recent analyses of morphology. With the aims of resolving the phylogeny of Philonthina and the position and, thus, validity of Hyptiomina, we performed phylogenetic analyses of the tribe Staphylinini based on molecular (six genes, 4471 bp) and morphological (113 characters) data including 138 taxa from all relevant lineages of Staphylinini. We found that ‘Staphylinini propria’ is a monophylum consisting of six lineages: current subtribes Anisolinina, Philonthina, Staphylinina and Xanthopygina; and two new subtribes, Algonina Schillhammer and Brunke and Philothalpina Chatzimanolis and Brunke. While the previously hypothesized Neotropical lineage of Philonthina was corroborated, Holisus was recovered as a separate subtribe, outside of Philonthina, within an informal ‘Southern Hemisphere clade’. Based on our analyses, we propose tentative new concepts of the polyphyletic genera Belonuchus and Philonthus. We propose the following taxonomic changes: synonymy of the subtribes Staphylinina Latreille (valid name) and Eucibdelina Sharp; resurrection of genera Barypalpus Cameron and Trapeziderus Motschulsky from synonymy with Rientis Sharp and Belonuchus Nordmann, respectively; transfer of 38 Belonuchus species, 16 Hesperus Fauvel species and one Philonthus Stephens species to Trapeziderus as new combinations; transfer of two Hesperus species to Eccoptolonthus Bernhauer as new combinations; transfer of one Belonuchus species to Paederomimus Sharp as a new combination; and transfer of Pridonius Blackwelder new status from its position as a subgenus of Quedius (subtribe Quediina) to Philonthina as a genus, and new combinations for its two described species.

A molecular investigation of the genus Ecklonia (Phaeophyceae, Laminariales) with special focus on the Southern Hemisphere.

Brown algae of the order Laminariales, commonly referred to as kelps, are the largest and most productive primary producers in the coastal inshore environment. The genus Ecklonia (Lessoniaceae, Phaeophyceae) consists of seven species with four species in the Northern Hemisphere and three in the Southern Hemisphere. It was recently transferred to the family Lessoniaceae based on phylogenetic analyses of nuclear and chloroplastic markers, though the type of the genus was not included and its relationship with allied genera Eckloniopsis and Eisenia remained unresolved. The present study is the first to produce a phylogeny focussed on the genus Ecklonia. It included sequences from nuclear, mitochondrial, and chloroplastic DNA, for most of the distribution range of the three current Southern Hemisphere species (Ecklonia radiata, Ecklonia maxima, and a sample of a putative Ecklonia brevipes specimen), sequences for East Asiatic species (Ecklonia cava, Ecklonia kurome, and Ecklonia stolonifera), as well as the closely related genera Eckloniopsis and Eisenia. Results confirmed E. radiata and E. maxima as two distinct species in South Africa, E. radiata as a single species throughout the Southern Hemisphere (in South Africa, Australia, and New Zealand) and East Asiatic species as a distinct lineage from the Southern Hemisphere clade. Results further pointed out a close sister relationship between Eckloniopsis radicosa and two Eisenia species (including the type species: Eisenia arborea) to the genus Ecklonia suggesting that the genera Eckloniopsis and Eisenia are superfluous.

Phylogeny of Hinterhubera Group and Related Genera (Hinterhuberinae: Astereae) Based on the nrDNA ITS and ETS Sequences

The phylogenetic relationships of six out of seven genera from the informal Hinterhubera group (Hinterhuberinae) and nine other subtribes in tribe Astereae primarily with Southern Hemisphere distributions were studied using internal and external transcribed spacer region nuclear DNA (ITS and ETS) sequence data. Bayesian and parsimony analyses were conducted on both datasets, independently and combined. Topologies resulting from the ITS and combined data sets were highly congruent, while the ETS based phylogenies were poorly resolved, probably because the characters are fewer and less informative. The monophyly of the Hinterhubera group was not confirmed, nor were the monophyly of the subtribes Podocominae, Lagenophorinae, Grangeinae, and Asterinae as delimited by Nesom and Robinson. Instead, our results suggest a closer relationship among the taxa from similar geographic areas. Within the Hinterhubera group, the monophyly of the genera has been confirmed. Westoniella was sister to Laennecia (Podocominae), while Hinterhubera was sister to Laestadia and Blakiella. The radiate Diplostephium and Guynesomia were disparately placed in the southern hemisphere clade and not related to the other radiate genera of Hinterhuberinae. Present analyses suggest that dioecy in Aztecaster and Baccharidinae evolved independently as hypothesized by Nesom. Archibaccharis (Baccharidinae) was sister to Plagiocheilus (Grangeinae). The analyses of ITS and ETS data, and Bayesian analysis of the combined dataset, resolved Baccharidinae as non monophyletic. Constraint analyses forcing a monophyletic Baccharidinae, with Plagiocheilus sister to Archibaccharis, did not reject monophyly of the subtribe.

Molecular evidence for long distance dispersal across the Southern Hemisphere in the Ganoderma applanatum-australe species complex ( Basidiomycota)

We examined phylogeographic relationships in the cosmopolitan polypore fungus Ganoderma applanatum and allies, and conservatively infer a possible age of origin for these fungi. Results indicate that it is very unlikely that members of this species complex diversified before the break-up of Gondwana from Laurasia ca 120 M years ago, and also before the final separation of the Gondwanan landmasses from each other that was achieved about 66 M years ago. An earliest possible age of origin of 30 M years was estimated from nucleotide substitution rates in the 18S rDNA gene. Phylogenetic reconstruction of a worldwide sampling of ITS rDNA sequences reveals at least eight distinct clades that are strongly correlated with the geographic origin of the strains, and also correspond to mating groups. These include one Southern Hemisphere clade, one Southern Hemisphere–Eastern Asia clade, two temperate Northern Hemisphere clades, three Asian clades, and one neotropical clade. Geographically distant collections from the Southern Hemisphere shared identical ITS haplotypes, and an ITS recombinant was noted. Nested clade analysis of a parsimony network among isolates of the Southern Hemisphere clade indicated restricted gene flow with isolation-by-distance among the New Zealand, Australia–Tasmania, Chile–Argentine, and South Africa populations, suggesting episodic events of long-distance dispersal within the Southern Hemisphere. This study indicates that dispersal bias plays a more important role than generally admitted to explain the Southern Hemisphere distribution of many taxa, at least for saprobic fungi.

Phylogenetic relationships within Luzula DC. and Juncus L. (Juncaceae): A comparison of phylogenetic signals of trnL-trnF intergenic spacer, trnL intron and rbcL plastome sequence data.

Juncus and Luzula are the largest, almost cosmopolitan, genera in the Juncaceae. Relationships within Juncus and Luzula and among other genera of Juncaceae (Distichia, Marsippospermum, Oxychloë, Patosia and Rostkovia) remain incompletely resolved. RbcL sequence data resolved a part of the supraspecific phylogeny, but many clades remain polytomic. For this reason, the non-coding cpDNA regions, trnL intron and trnL-trnF intergenic spacer, were sequenced. We intended to create hypotheses of relationships within Juncaceae and to test the classification of the sections, but a primary goal to this study was to assess the relationships within Juncus and Luzula and to test for monophyly of groups recognized from rbcL data (especially the monophyly of genus Luzula and the Southern Hemisphere Clade (SHC)). Furthermore, we tested the influence of different rooting and ingroup composition on the tree topology. The parsimony analyses revealed several well-supported lineages. The traditionally distinguished genus Luzula is monophyletic and Juncus is non-monophyletic. Two subgenera of Luzula (Pterodes and Luzula) are non-monophyletic, while subg. Marlenia forms a sister group to the whole Luzula clade (trnL-F data set). Within Juncus, both subgenus Juncus and subgenus Agathryon are non-monophyletic. SHC is clustered not only with the South African J. lomatophylus and J. capensis, but also together with members of the section Juncus, Caespitosi and Graminifolii. These sections form a well-separated sister group to the SHC. Within the genera Juncus and Luzula, monophyly is demonstrated for a number of groups (e.g., Juncus section Stygiopsis, Luzula section Luzula) but questioned for others (e.g., Juncus section Graminifolii). The unusual, separate positioning of Juncus trifidus and J. monanthos were clarified by trnL-trnF sequence data, but vary within the tree topology depending on outgroup selection and also due to LBA phenomenon.

Multiple origins of Southern Hemisphere Anemone (Ranunculaceae) based on plastid and nuclear sequence data

Using two molecular data sets, the plastid atpB-rbcL intergenic spacer region and the nuclear ribosomal internal transcribed spacer regions (ITS), the taxonomic affinities of two newly available Anemone species from the Southern Hemisphere were tested. From previous work based on morphology and geographic distribution, it was assumed that A. tenuicaulis from New Zealand was most closely related to the Tasmanian A. crassifolia, whereas the affinity of A. antucensis from Chile and Argentina was regarded as uncertain. Analyses of molecular sequence data from these and 18 other species of Anemone s.lat. (with Clematis as outgroup) result in trees largely congruent with past analyses based on morphology and plastid restriction site data. They strongly support A. richardsonii and A. canadensis (with boreal distributions in the Northern Hemisphere) as paraphyletic to a well supported Southern Hemisphere clade consisting of A. antucensis and A. tenuicaulis. This group of four species is part of an otherwise predominantly Northern Hemisphere assemblage (subgenus Anemonidium s.lat., chromosome base number x=7), including A. narcissiflora, A. obtusiloba, A. keiskeana and A. (=Hepatica) americana. All other austral species included in the present sampling, A. crassifolia (Tasmania), A. knowltonia (=Knowltonia capensis), and A. caffra (both South African), form a separate clade, sister to A. (=Pulsatilla) occidentalis and other Northern Hemisphere anemones (subgenus Anemone s.lat., x=8). Possible phytogeographical links of the Southern Hemisphere species are discussed.

Classification, Origin, and Diversification of the New Zealand Hebes (Scrophulariaceae)

The New Zealand hebes (Scrophulariaceae) are members of a large Southern Hemisphere clade nested within Veronica. Analysis of ITS and rbcL sequences suggests that the New Zealand species are derived from a single common ancestor that arrived via long-distance dispersal. After the establishment of this initial founder population in New Zealand, the hebes have undergone at least two major episodes of diversification, giving rise to six clades. The great degree of morphological diversity in the New Zealand hebes contrasts with a corresponding low level of sequence divergence. New Zealand was a source of new emigrants to other regions in the South Pacific that were preadapted to high mountains or forest margins. Our results suggest that two instances of long-distance dispersal from New Zealand to South America, at least one instance from New Zealand to Australia, and one instance from New Zealand to New Guinea have occurred relatively recently. Shorter hops to the Chatham Islands and the subantarctic islands are also supported by the sequence data.

Relationships of the Osmeroid Fishes and the Use of Reductive Characters in Phylogenetic Analysis

The phylogenetic relationships of the osmeroid fishes are examined in the context of character congruence. The Osmeroidei is monophyletic, and its sister taxon is the monophyletic Argentinoidei. The division of osmeroids into Northern and Southern Hemisphere groups is largely corroborated. Two problematic taxa, the neotenic Salangidae and the monotypic Lepidogalaxias salamandroides, are hypothesized to be members of the Southern Hemisphere clade, in which reductive evolution has been common