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Clements M.A.,Center for Australian National Biodiversity Research | Tupac Otero J.,National University of Colombia | Miller J.T.,Center for Australian National Biodiversity Research
Australian Journal of Botany | Year: 2011

A study to evaluate the relationships in subtribe Pterostylidinae (Cranichideae: Orchidaceae) was undertaken using DNA sequences from the nuclear ribosomal ITS region (256 taxa) and plastid matK (subset of 37 taxa). Parsimony analysis of nuclear, plastid and combined datasets revealed that there is strong support for the monophyly of Pterostylidinae, and three major groups therein. Clades AC contain nine, possibly 10, identifiable groups supported by morphological synapomorphies. Clade A comprises the following two major, strongly supported groups that correlate with morphological synapomorphies: (1) Speculantha (including Petrorchis) and (2) Linguella and Eremorchis, sister to an unresolved polytomy containing Taurantha, a paraphyletic Crangonorchis and polyphyletic Diplodium. There is no support for continued recognition of Taurantha, Crangonorchis, Linguella and Eremorchis, all of which are embedded within the broader, strongly supported, monophyletic Diplodium. Clade B represents true Pterostylis. Clade C contains the morphologically disparate Bunochilus, Hymenochilus, Oligochaetochilus, Pharochilum, Plumatichilos, Stamnorchis and Urochilus (including Ranorchis) in a partially resolved tree. There is strong molecular and morphological synapomorphic internal support for the recognition of these taxa as genera. Our results revealed that none of the presently proposed classification systems for Pterostylidinae truly accounts for the underlying phylogenetic signal. A streamlined classification system, therefore, seems warranted, although further research based on a larger plastid DNA dataset is required to elucidate relationships in Clade C. © 2011 CSIRO.


Clements M.A.,Center for Australian National Biodiversity Research | Howard C.G.,Center for Australian National Biodiversity Research | Miller J.T.,Center for Australian National Biodiversity Research
American journal of botany | Year: 2015

PREMISE OF THE STUDY: The classification of the primarily Australasian group of orchids Caladenia and allied genera (Caladeniinae: Diurideae) containing 71 federally listed threatened species has proven controversial. Analyzing these species using genetic material will provide a sound basis for their classification and the capacity to ensure accurate conservation measures can be implemented.METHODS: We present a multigene analysis based on nuclear ribosomal ITS and five plastid regions from 54 species representing all major taxonomic groups within Caladeniinae.KEY RESULTS: In our combined analysis, apart from Leptoceras and Praecoxanthus, all Caladenia ingroup taxa form a strongly supported clade that is also supported by morphological synapomorphies (parallel leaf venation; leaf solitary, lanceolate, covered with glandular or eglandular trichomes). Characters and character states historically used to delimit taxa were revealed to be homoplasious and therefore do not support recognition of Arachnorchis, Cyanicula, Drakonorchis, Ericksonella, Jonesiopsis, Petalochilus, Pheladenia, and Stegostyla as previously proposed. Glossodia and Elythranthera are shown to be a specialist group embedded within Caladenia.CONCLUSIONS: Based on our results, none of the current systems of classification of the subtribe is satisfactory. Instead our results point to Lindley's 1840 interpretation of Caladenia, but including Glossodia and Elythranthera, as being the most accurate reflection of the group. Accordingly, a renewed reclassification of Caladeniinae is proposed as well as several new combinations. © 2015 Botanical Society of America, Inc.


Cargill D.C.,Center for Australian National Biodiversity Research | Cargill D.C.,Khan Research Laboratories
Phytotaxa | Year: 2016

The hornwort genus Notothylas is newly recorded for Australia. Detailed descriptions, illustrations and a key to the two known species, N. orbicularis and N. javanica are provided. A peculiar phenomenon involving presentation of the sporophyte on the ventral (rather than the dorsal) surface of the gametophyte, known only in Australian populations of Notothylas, is reported and discussed. © 2016 Magnolia Press.


Barrett R.L.,Center for Australian National Biodiversity Research | Henwood M.J.,University of Sydney
Telopea | Year: 2015

Astrotricha hamptonii F.Muell. (Araliaceae) is essentially restricted to the Hamersley Range in the Pilbara region of Western Australia where it grows on cliffs in rock fissures, and on scree slopes. This distinctive plant almost always grows in association with iron ore deposits on banded ironstone formations. Recognisable from the air, this species was used by prospector and pastralist, Lang Hancock's prospecting partner, Ken McCamey, to accurately map the distribution of many of the richest iron ore deposits in the Hamersley Range. This paper provides the first detailed taxonomic description of this species to be published in English. A summary of its use for bioprospecting is provided. © 2015 Royal Botanic Gardens and Domain Trust.


Christine Cargill D.,Center for Australian National Biodiversity Research | Christine Cargill D.,Khan Research Laboratories | Milne J.,Royal Botanic Gardens
Polish Botanical Journal | Year: 2013

A new genus Austroriella Cargill and Milne and species Austroriella salta Milne and Cargill within the family Riellaceae is described. Known only from the type location at the margins of a saline lake in Western Australia it is the first record and description of a terrestrial species within this typically aquatic family. Female plants are typical of the family with a single reduced wing bearing a row of archegonia; male plants are not typical and are naviculate in form enclosing several rows of enclosed antheridia not unlike the males of Sphaerocarpos. Unlike Sphaerocarpos this species does bear oil bodies. Differences and affinities are also outlined briefly with closely related genera within the order Sphaerocarpales.


Barrett L.G.,CSIRO | Encinas-Viso F.,Center for Australian National Biodiversity Research | Burdon J.J.,CSIRO | Thrall P.H.,CSIRO
Frontiers in Plant Science | Year: 2015

Properties encompassed by host-pathogen interaction networks have potential to give valuable insight into the evolution of specialization and coevolutionary dynamics in host-pathogen interactions. However, network approaches have been rarely utilized in previous studies of host and pathogen phenotypic variation. Here we applied quantitative analyses to eight networks derived from spatially and temporally segregated host (Linum marginale) and pathogen (Melampsora lini) populations. First, we found that resistance strategies are highly variable within and among networks, corresponding to a spectrum of specialist and generalist resistance types being maintained within all networks. At the individual level, specialization was strongly linked to partial resistance, such that partial resistance was effective against a greater number of pathogens compared to full resistance. Second, we found that all networks were significantly nested. There was little support for the hypothesis that temporal evolutionary dynamics may lead to the development of nestedness in host-pathogen infection networks. Rather, the common patterns observed in terms of nestedness suggests a universal driver (or multiple drivers) that may be independent of spatial and temporal structure. Third, we found that resistance networks were significantly modular in two spatial networks, clearly reflecting spatial and ecological structure within one of the networks. We conclude that (1) overall patterns of specialization in the networks we studied mirror evolutionary trade-offs with the strength of resistance; (2) that specific network architecture can emerge under different evolutionary scenarios; and (3) network approaches offer great utility as a tool for probing the evolutionary and ecological genetics of host-pathogen interactions. © 2015 Barrett, Encinas-Viso, Burdon and Thrall.


PubMed | Leiden University and Center for Australian National Biodiversity Research
Type: | Journal: PhytoKeys | Year: 2015

In 2013, an unidentified species of Dendrochilum appeared in cultivation under the commercial trade name Big Pink. Using sequences of the nuclear ribosomal ITS1-5.8S-ITS2 region and of the plastid matK and ycf1 genes, we examined the phylogenetic relationships between Big Pink and six other species of the phenetically defined Dendrochilum subgen. Platyclinis sect. Eurybrachium. Separate and combined analyses (using Bayesian, Maximum Likelihood and Parsimony inference) showed consistent placement of the unidentified species within a statistically well supported clade. Furthermore, the multi-copy nrITS marker showed clear distinct peaks. Thus, we found no evidence that Big Pink could be a hybrid. Against this background, and further supported by species-specific mutations in (at least) nrITS and ycf1, we formally describe Big Pink as a new species under the name Dendrochilum hampelii. Morphologically, it is most similar to Dendrochilum propinquum, but it differs in a number of characters. Of the two cultivated individuals available for our study, one was of unrecorded provenance. The other allegedly originated from the Philippines. Observations of the species occurring in the wild in the Philippines in the northern provinces of Bukidnon and Misamis Oriental on the island of Mindanao confirmed this.


PubMed | Center for Australian National Biodiversity Research and CSIRO
Type: | Journal: Frontiers in plant science | Year: 2015

Properties encompassed by host-pathogen interaction networks have potential to give valuable insight into the evolution of specialization and coevolutionary dynamics in host-pathogen interactions. However, network approaches have been rarely utilized in previous studies of host and pathogen phenotypic variation. Here we applied quantitative analyses to eight networks derived from spatially and temporally segregated host (Linum marginale) and pathogen (Melampsora lini) populations. First, we found that resistance strategies are highly variable within and among networks, corresponding to a spectrum of specialist and generalist resistance types being maintained within all networks. At the individual level, specialization was strongly linked to partial resistance, such that partial resistance was effective against a greater number of pathogens compared to full resistance. Second, we found that all networks were significantly nested. There was little support for the hypothesis that temporal evolutionary dynamics may lead to the development of nestedness in host-pathogen infection networks. Rather, the common patterns observed in terms of nestedness suggests a universal driver (or multiple drivers) that may be independent of spatial and temporal structure. Third, we found that resistance networks were significantly modular in two spatial networks, clearly reflecting spatial and ecological structure within one of the networks. We conclude that (1) overall patterns of specialization in the networks we studied mirror evolutionary trade-offs with the strength of resistance; (2) that specific network architecture can emerge under different evolutionary scenarios; and (3) network approaches offer great utility as a tool for probing the evolutionary and ecological genetics of host-pathogen interactions.


PubMed | Australian National University and Center for Australian National Biodiversity Research
Type: Journal Article | Journal: Molecular ecology | Year: 2016

Species delimitation has seen a paradigm shift as increasing accessibility of genomic-scale data enables separation of lineages with convergent morphological traits and the merging of recently diverged ecotypes that have distinguishing characteristics. We inferred the process of lineage formation among Australian species in the widespread and highly variable genus Pelargonium by combining phylogenomic and population genomic analyses along with breeding system studies and character analysis. Phylogenomic analysis and population genetic clustering supported seven of the eight currently described species but provided little evidence for differences in genetic structure within the most widely distributed group that containing P.australe. In contrast, morphometric analysis detected three deep lineages within Australian Pelargonium; with P.australe consisting of five previously unrecognized entities occupying separate geographic ranges. The genomic approach enabled elucidation of parallel evolution in some traits formerly used to delineate species, as well as identification of ecotypic morphological differentiation within recognized species. Highly variable morphology and trait convergence each contribute to the discordance between phylogenomic relationships and morphological taxonomy. Data suggest that genetic divergence among species within the Australian Pelargonium may result from allopatric speciation while morphological differentiation within and among species may be more strongly driven by environmental differences.


PubMed | Center for Australian National Biodiversity Research
Type: Journal Article | Journal: American journal of botany | Year: 2015

The classification of the primarily Australasian group of orchids Caladenia and allied genera (Caladeniinae: Diurideae) containing 71 federally listed threatened species has proven controversial. Analyzing these species using genetic material will provide a sound basis for their classification and the capacity to ensure accurate conservation measures can be implemented.We present a multigene analysis based on nuclear ribosomal ITS and five plastid regions from 54 species representing all major taxonomic groups within Caladeniinae.In our combined analysis, apart from Leptoceras and Praecoxanthus, all Caladenia ingroup taxa form a strongly supported clade that is also supported by morphological synapomorphies (parallel leaf venation; leaf solitary, lanceolate, covered with glandular or eglandular trichomes). Characters and character states historically used to delimit taxa were revealed to be homoplasious and therefore do not support recognition of Arachnorchis, Cyanicula, Drakonorchis, Ericksonella, Jonesiopsis, Petalochilus, Pheladenia, and Stegostyla as previously proposed. Glossodia and Elythranthera are shown to be a specialist group embedded within Caladenia.Based on our results, none of the current systems of classification of the subtribe is satisfactory. Instead our results point to Lindleys 1840 interpretation of Caladenia, but including Glossodia and Elythranthera, as being the most accurate reflection of the group. Accordingly, a renewed reclassification of Caladeniinae is proposed as well as several new combinations.

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