scholarly journals Molecular Studies of New Zealand Fucales: Phylogeography, Phylogeny and Taxonomy in Carpophyllum and Cystophora (Phaeophyceae)

2021 ◽  
Author(s):  
◽  
Joe Buchanan

<p>Genetic variation in Carpophyllum Greville and Cystophora J. Agardh (Fucales, Phaeophyceae) was investigated at a variety of scales. An extensive survey of mitochondrial spacer variation in Carpophyllum maschalocarpum from 32 populations around New Zealand shows strong population differentiation at relatively small scales (50–100 kilometres), but also pathways of long distance dispersal that connect populations over much greater distances. In addition, historical climate change appears to have restricted C. maschalocarpum to the northern North Island during the last glacial maximum, with subsequent southward range expansion revealed by low genetic diversity in southern populations. These results are consistent with limited dispersal at the gamete and zygote stage, expected in fucalean algae, but with occasional long distance dispersal by detached floating thalli. The genetic signature suggests these two modes of dispersal are decoupled. Internal Transcribed Spacers sequences show little differentiation between C. maschalocarpum and C. angustifolium, and hybridisation was found in several populations where these species are broadly sympatric. In the Bay of Plenty the two species had different ITS ribotypes, but most C. angustifolium specimens had a mitochondrial spacer haplotype that clustered with C. maschalocarpum haplotypes. This indicates mitochondrial introgression from C. maschalocarpum into C. angustifolium. In Northland species were difficult to separate by morphology or molecular markers, and some populations appear to be comprised entirely of hybrids. Genetic distances between different species of Cystophora are very variable, and in some cases intra-species distances are similar to interspecies distances. This is problematic for DNA barcoding methods that rely on thresholds between inter-species and intra-species genetic distances. In some (but not all) cases, the absence of molecular differentiation can be attributed to oversplitting of Cystophora species by morphological methods, and I synonymise C. congesta with C. retroflexa, and C. distenta with C. scalaris. These studies exemplify the difficulties of delimiting species in brown algae: Morphology is often misleading or uninformative; genetic differentiation of species is very variable and often low; and species’ histories show complex patterns of isolation and secondary contact. I argue for an explicitly historical concept of species, with species’ history included in species descriptions.</p>

2021 ◽  
Author(s):  
◽  
Joe Buchanan

<p>Genetic variation in Carpophyllum Greville and Cystophora J. Agardh (Fucales, Phaeophyceae) was investigated at a variety of scales. An extensive survey of mitochondrial spacer variation in Carpophyllum maschalocarpum from 32 populations around New Zealand shows strong population differentiation at relatively small scales (50–100 kilometres), but also pathways of long distance dispersal that connect populations over much greater distances. In addition, historical climate change appears to have restricted C. maschalocarpum to the northern North Island during the last glacial maximum, with subsequent southward range expansion revealed by low genetic diversity in southern populations. These results are consistent with limited dispersal at the gamete and zygote stage, expected in fucalean algae, but with occasional long distance dispersal by detached floating thalli. The genetic signature suggests these two modes of dispersal are decoupled. Internal Transcribed Spacers sequences show little differentiation between C. maschalocarpum and C. angustifolium, and hybridisation was found in several populations where these species are broadly sympatric. In the Bay of Plenty the two species had different ITS ribotypes, but most C. angustifolium specimens had a mitochondrial spacer haplotype that clustered with C. maschalocarpum haplotypes. This indicates mitochondrial introgression from C. maschalocarpum into C. angustifolium. In Northland species were difficult to separate by morphology or molecular markers, and some populations appear to be comprised entirely of hybrids. Genetic distances between different species of Cystophora are very variable, and in some cases intra-species distances are similar to interspecies distances. This is problematic for DNA barcoding methods that rely on thresholds between inter-species and intra-species genetic distances. In some (but not all) cases, the absence of molecular differentiation can be attributed to oversplitting of Cystophora species by morphological methods, and I synonymise C. congesta with C. retroflexa, and C. distenta with C. scalaris. These studies exemplify the difficulties of delimiting species in brown algae: Morphology is often misleading or uninformative; genetic differentiation of species is very variable and often low; and species’ histories show complex patterns of isolation and secondary contact. I argue for an explicitly historical concept of species, with species’ history included in species descriptions.</p>


Author(s):  
E. Punithalingam

Abstract A description is provided for Scirrhia pini[Mycosphaerella pini]. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On pines including Pinus radiata and its hybrids, P. halepensis, P. canariensis, P. carbaea, P. ponderosa, P. nigra and others, Pseudotsuga menziesii (46, 2860), Larix decidua (49, 273). DISEASE: Dothistroma blight; red band. GEOGRAPHICAL DISTRIBUTION: North America (Canada, USA including Alaska), South America (Argentina, Brazil, Chile, Uruguay), Australasia and Oceania (New Zealand), Asia (Brunei, India, Japan), Africa (Ethiopia, Kenya, Malawi, Rhodesia, Swaziland, Tanzania, Uganda), Europe (Austria, France, Rumania, UK, USSR (Republic of Georgia), Yugoslavia) (CMI Map 419, ed. 2, 1970; record in CMI Herbarium). TRANSMISSION: By airborne conidia released and dispersed by a splash take-off mechanism for short distances. Long distance dispersal may be by transport of infected material, such as nursery stock and, under special conditions, clouds may carry sporal inoculum (43, 2100). Survival time of inoculum in the form of cast, infected foliage on the forest floor is limited to 2-6 months under moist conditions (50, 2003).


Zootaxa ◽  
2007 ◽  
Vol 1425 (1) ◽  
pp. 1-10 ◽  
Author(s):  
BRENT D. OPELL ◽  
ANDREA M. BERGER ◽  
SOPHIA M. BOUS ◽  
MICHAEL L. MANNING

Members of the genus Amaurobioides construct silk retreats in rock crevices of the marine spray zone, a harsh and unusual habitat for spiders. This study expands the distribution records of three morphological species of Amaurobioides found on the eastern and southern coasts of New Zealand’s South Island and uses mitochondrial DNA to examine their relationships and characterize their dispersal capabilities. Both 16S and ND1 sequences distinguish A. pletus found on the northeastern coast from a complex of two southern species comprised of A. maritimus from the mainland and A. picunus from Stewart Island. Neither 16S DNA nor ND1 protein separates these southern species. However, ND1 parsimony and likelihood analyses place 10 of 11 Stewart Island specimens in a clade of low support that nests deeply within A. maritimus. A nested haplotype analysis characterizes A. maritimus and A. picunus populations as having restricted gene flow/dispersal but with some long distance dispersal. Genetic distances between A. pletus and the A. maritimus-A. picunus complex indicate a Pliocene origin, whereas distances between A. maritimus and A. picunus suggest a Pleistocene divergence.


2011 ◽  
Vol 59 (3) ◽  
pp. 262 ◽  
Author(s):  
Gunnar Keppel ◽  
Peter Prentis ◽  
Ed Biffin ◽  
Paul Hodgskiss ◽  
Susana Tuisese ◽  
...  

We examined evolutionary relationships, hybridisation and genetic diversity in species of Dacrydium (Podocarpaceae) in Remote Oceania, where it is restricted to New Caledonia and Fiji. We used cpDNA sequence (trnL–trnF) data to construct a phylogeny and estimate taxon divergence by using a relaxed molecular clock approach. The phylogeny was verified using allozymes, which were also used to investigate genetic diversity of all species and the hybridisation dynamics of two endangered species, D. guillauminii and D. nidulum. Our results suggested that Dacrydium species in Remote Oceania form a monophyletic group that arose and diversified within the last 20 million years through long-distance dispersal and a range of speciation mechanisms. Whereas we detected no hybridisation between the Fijian species D. nausoriense and D. nidulum, we confirmed hybridisation between D. guillauminii and D. araucarioides in New Caledonia and determined introgression to be assymetric from the widespread D. araucarioides into the rare, restricted-range species D. guillauminii. In addition, D. guillauminii had lower genetic diversity than did the other species of Dacrydium studied, which had genetic diversity similar to that of other gymnosperms. Our results provided evidence for the recent and complex diversification of Dacrydium in Remote Oceania. In addition, low genetic diversity of and introgression from D. araucarioides, are of grave concern for the conservation of D. guillauminii.


2012 ◽  
Vol 44 (2) ◽  
pp. 189-246 ◽  
Author(s):  
Gintaras KANTVILAS

AbstractWith 30 species, Tasmania is a major area of species diversity in the genus Menegazzia. Seven of these are new to science: M. abscondita Kantvilas, known from Tasmania and New Zealand, and M. athrotaxidis Kantvilas, M. hypogymnioides Kantvilas, M. petraea Kantvilas, M. ramulicola Kantvilas, M. subtestacea Kantvilas and M. tarkinea Kantvilas, all endemic to Tasmania. An identification key, descriptions based exclusively on Tasmanian collections, and detailed discussion of distribution, ecology, chemical composition and inter-species relationships are provided. All literature records of Menegazzia species pertaining to Tasmania are accounted for. New synonyms include: Menegazzia prototypica P. James and Parmelia pertusa var. coskinodes F. Wilson [synonyms of M. myriotrema (Müll. Arg.) R. Sant.], M. fertilis P. James [a synonym of M. platytrema (Müll. Arg.) R. Sant.] and Parmelia pertusa var. montana F. Wilson (a synonym of M. subtestacea). Incorrectly recorded species that should be deleted from the Tasmanian census include M. castanea P. James & D. J. Galloway (present on Macquarie Island) and M. testacea P. James & D. J. Galloway (endemic to New Zealand). The South American species, M. sanguinascens (Räs.) R. Sant., is recorded in Australasia (Tasmania) for the first time, whereas the widespread south-eastern Australian M. norstictica P. James is recorded for Western Australia. Salient features of the genus are discussed, including morphology, anatomy and chemistry. The biogeography of the genus is explored briefly. Twelve species (40%) are endemic to Tasmania, a level of endemism unmatched by any other species-rich genus on the island. Twelve species are shared with mainland Australia, eleven are shared with New Zealand, and only four species are shared with southern South America, all of which are sorediate, suggesting they are products of long-distance dispersal.


2006 ◽  
Vol 84 (8) ◽  
pp. 1266-1281 ◽  
Author(s):  
Gabriel Bernardello ◽  
Gregory J. Anderson ◽  
Tod F. Stuessy ◽  
Daniel J. Crawford

We review the hypothesized origin and the methods of arrival of the angiosperm colonists to the Juan Fernandez Islands. We also summarize the dispersal capabilities of the current flora, including data on fruit type, fruit length, and dispersal unit length, correlating these features with dispersal and establishment. Most species originated from South America, followed by Pantropical, Australian, New Zealand, and Pacific colonizers. Sea and land birds were the most important initial long-distance dispersal agents. Most colonizing species are hermaphroditic flowered, and thus all dispersal methods are represented among them. Monoecious, andromonoecious and gynomonoecious, dioecious, and polygamous species were mainly carried by birds. Most wind- and bird-pollinated colonizing genera arrived with birds as did most annual herbs and species with bright-colored flowers. In the current flora, the majority of the species have dry fruits. In monoecious, andromonoecious and gynomonoecious, and dioecious species, achenes predominate. Fleshy fruits are limited to perennials. Most species have medium to small dispersal units, and generally, the larger the flower, the larger the fruit. Large- and medium-sized dispersal units are common in shrubs and trees. Abiotic dispersal is common in the current flora, which may reflect the ancestral dispersal capability of the colonizers, or adaptation to the absence of a fauna to disperse seeds and fruits. Anemochorous and autochorous species are mainly perennial and have medium to large, unisexual flowers. Anemochorous species have small dispersal units and dull-colored flowers, whereas large dispersal units and brightly colored flowers are frequent in autochorous species. Medium-sized dispersal units are represented in autochorous or ornithochorous species. The establishment and evolution of this flora was previously discussed to have occurred with very few pollination and (or) reproductive options. This study suggests that elements associated with dispersal are also analogously limited.


Zootaxa ◽  
2010 ◽  
Vol 2650 (1) ◽  
pp. 1
Author(s):  
MATTHEW J. COLLOFF

Three new species of oribatid mite belonging to the genus Crotonia are described: one from Lord Howe Island (C. gorgonia sp. nov.) and two (C. norfolkensis sp. nov. and C. utricularia sp. nov.) from Norfolk Island, South-west Pacific. Crotonia gorgonia sp. nov. belongs to the Capistrata species group which reaches its highest diversity in Australia but is absent from New Zealand. Crotonia norfolkensis sp. nov. is a member of the Cophinaria group, recorded from Australia, New Zealand and New Caledonia, but with closest morphological similarity to C. brachyrostrum (Hammer, 1966) from New Zealand. Crotonia utricularia sp. nov. belongs to the Unguifera group, which reaches its highest diversity in New Zealand, is absent from Australia, and is present on Vanuatu and the Marquesas. The distribution of members of the species-groups of Crotonia in the south-western Pacific indicates that the species from Lord Howe Island has affinities with species from Australia, while the species from Norfolk Island are both most similar to species from New Zealand, and represents further evidence of the capacity of Crotonia spp. for long-distance dispersal to oceanic islands.


2002 ◽  
Vol 50 (1) ◽  
pp. 127 ◽  
Author(s):  
Kitty Vijverberg ◽  
Louis Lie ◽  
Konrad Bachmann

The Australian and New Zealand Microseris is supposed to have evolved from one or a few diaspores after a unique event of long-distance dispersal from western North America. At present, the plant group includes two species, M. lanceolata (Walp.) Sch.-Bip. and M. scapigera (Forst.) Sch.-Bip., each with two morphologically and ecologically divergent ecotypes. In spite of this classification, the morphological variation within and among ecotypes is not entirely consistent, and molecular investigations show evidence for the, possibly recent, occurrence of hybridisations between plants of different ecotypes. The present study investigates the overall morphological similarities among 1–4 plants of each of 54 Australian and New Zealand Microseris populations. The aim of the study was to gain further insights into the delimitation of species and ecotypes, the placement of populations that could thus far not be assigned to an ecotype and the adaptive radiation of the plant group. The results confirm the previously defined ecotypes and assign all but two of the questionable populations to ecotypes. They show that a broad range of character states rather than a few 'diagnostic' ones are specific for the ecotypes. The data confirm our earlier conclusion from molecular results, indicating that ecotype characteristics are maintained or reestablished by selection or adaptation, after dispersal or hybridisation between ecotypes. Despite (incidental) genetic exchange among populations of different ecotypes, the process of adaptive radiation is progressing. The combined morphological and molecular results are not incongruent with the present species delimitation. However, they also may support the split up of M. scapigera into two species and other phylogenetic solutions.


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