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1.
This is the first report of the growth in culture of Porphyra subtumens J. Agardh ex Laing (Bangiales, Rhodophyta), an obligate epiphyte of Durvillaea species and endemic to New Zealand waters. Archeospores, previously observed on field material, develop directly into the blade phase. Spores released from field collected blades form conchocelis. Conchospores develop into new blades, completing the life history in culture. Earlier reports of reproduction in P. subtumens gave conflicting accounts with some authors citing this species as having an asexual, monophasic life history with an unusual form of spore production, while others described spermatangia and carposporangia on the blade phase.  相似文献   

2.
A new species of Porphyra, Porphyra lilliputiana, is described for the New Zealand region. This species is very small ([5] 10–20 [35] mm) and is found growing epiphytically, epilithically and epizoically on upper inter-tidal shores of moderate exposure. Field-collected material of P. lilliputiana possessed archeosporangia, endosporangia, spermatangia and zygotosporangia. In culture, archeospores vi/ere released and germinated to form thalli. Endosporangia either developed directly into thalli or released endospores which individually formed thalli. Zygotospores developed into the concho-celis phase, which formed conchosporangia. Released conchospores formed thalli. This species is distinguished by its small size, arrangement of reproductive cells, occurrence of endosporangia, dentate margin and habitat.  相似文献   

3.
Analysis of nuclear small subunit ribosomal RNA gene (18S rDNA) sequence data from 123 samples of the red algal genus Bangia from mainland New Zealand has revealed diversity exceeding that reported for the genus from any other region in the world. Our study resolves two New Zealand Bangia taxa basal to the order Bangiales, and five clades of Bangia, four of which include New Zealand members. The basal taxa are separated from each other by 139 bp and differ from all other Bangia taxa in the New Zealand region by 103-163 bp over approximately 1750 bp 18S rDNA sequence data. Our results reveal a Bangia flora of previously unsuspected richness, and show that the simple morphology of these organisms obscures significant levels of genetic diversity. The presence of high diversity and retention of basal taxa in New Zealand Bangia raises the prospect that the southern hemisphere, and particularly eastern Gondwana, is not only a centre of diversity, but a centre of origin for the modern Bangiales.  相似文献   

4.
Commercial interest in harvesting wild stocks ofPorphyra and concern for this prized resource by the Maori community highlighted the need to investigate the impact of harvest method and timing onPorphyra beds. Harvesting trials were carried out at two locations near Kaikoura (South Island) and one in Wellington (southern North Island) between June 1987 and September 1987. At each of five sampling sites, ten replicate sets of four quadrats were used to test the effects of harvest method and timing on yield and regeneration. The method of harvest had a major effect on the extent of regeneration: in quadrats in which thePorphyra had been cut with basal portions left intact there were harvestable plants within two months, whereas in quadrats which were cleared of allPorphyra there was very little growth after the same period. Harvests in the latter half of thePorphyra growing season gave greater yields at all sites except Wellington. Several species ofPorphyra were found to exist at the Kaikoura sampling sites and a single, different, species at the Wellington site. There were site to site differences in the yields.  相似文献   

5.
The cell wall polysaccharides of two species of red algae, which are adapted to both freshwater and marine environments, were analysed to determine the effect of these widely different environments on their commercially important agarocolloids and to investigate the possible role of the cell wall in environmental adaptation. Cell wall polymers of freshwater isolates of Bangia atropurpurea (Roth) C. Agardh and cultured freshwater and marine Bostrychia moritziana (Sonder ex Kützing) J. Agardh were isolated and the polysaccharides chemically fractionated and characterized. Wall polysaccharides of freshwater B. atropurpurea were similar to those previously reported for marine isolates with repeating disac-charide units of agarose and porphyran predominant in the hot water extracts. In the insoluble residues, 3-iinked galactosyl and 4-linked mannosyl residues were predominant. Bostrychia moritziana wall polysaccharides included agarocolloids with various patterns of methyl ether substitution similar to those previously described for other Ceramiales. Differences in the position of methyl ether substituents were detected in the hot water extracts of the freshwater and marine specimens. Polymers of freshwater ß. moritziana cultures were composed of a complex mixture of repeating disaccharide units including 2′-O-methyl agarose, 6-O-methyI agarose and 2′-O-methyl porphyran. Polymers of marine isolates of ß. moritziana differ in that they contain only trace amounts of 2-O-methyl saccharides and increased amounts of 6-O-amethyl saccharides. The hot water insoluble residues of both freshwater and marine isolates of ß. moritziana contain a mixture of 3-linked galactosyl and 4-linked glucosyl residues. These results indicate that the adaptive response of B. moritziana to changing osmotic and ionic conditions may include changes in cell wall chemistry: notably, the pattern of methyl ether substitution.  相似文献   

6.
The New Zealand distributions of three species of Boeckella (Copepoda, Calanoida), B. triarticulata, B. dilatata and B. hamata are mapped. B. triarticulata is primarily a pond dweller but is also found in reservoirs and shallow lakes. B. dilatata is mainly found in the deeper glacial lakes and ponds in the central region of the South Island and B. hamata has a more widespread distribution in lakes and ponds in the South Island and lower half of the North Island. Differences in temperature optima, food requirements and dispersal ability among the three Boeckella species are related to vicariant events to explain their distribution in New Zealand.  相似文献   

7.
The genus Dudresnaya is reported for the first time in New Zealand waters. Samples were collected in Bay of Islands, northern New Zealand, on rhodolith beds and at the edge of a rocky reef, between ?5 and ?10 m depth. The species was identified by morphological and anatomical characters as Dudresnaya capricornica and its identity was confirmed by molecular sequence data. This species is characterized by terete radial branches, outer cortical cells cylindrical, presence of hexagonal crystals, lack of annulation and mucilage coat on auxiliary cell branches, oblique division of carpogonium and cystocarps no cleft. The rbcL phylogenetic analysis showed the genus Dudresnaya is strongly supported and sister to taxa in the family Dumontiaceae. This family is also closely related to the families Rhizophillidaceae and Kallymeniaceae. This is the first record of the family Dumontiaceae in New Zealand.  相似文献   

8.
Aim We test hypotheses regarding the origin of diversity and patterns of species richness in and around the New Zealand Southern Alps with 25 species of Chionochloa (Poaceae, Danthonioideae). Location New Zealand. Methods We inferred a well‐resolved and mostly robustly supported chloroplast phylogeny based on multiple DNA sequence markers (trnT–L–F, rpl16, trnD–psbM, atpB–rbcL, matK and ndhF), sampling 92% of the recognized species and 82% of the subspecific taxa. Nuclear ribosomal internal transcribed spacer sequences were also sampled, but proved uninformative. Biogeographic reconstruction and character optimization were done using both parsimony and likelihood approaches, and molecular dating used relaxed clock approaches. Results Most of the species diversity in Chionochloa stemmed from a common ancestor in the southern South Island with subsequent dispersal between areas. One clade of apparently cryptic taxa diversified within the central South Island ‘endemism gap’, persisting there throughout at least the latter half of the Pleistocene. Exclusively alpine and other habitat specialist species originated independently, the former relatively recently (between 7.6 Ma and the present). Main conclusions The phylogeny of Chionochloa and other published phylogenies of New Zealand plant groups demonstrate that the higher degree of endemism in the north and south of the New Zealand South Island relative to a central endemism gap cannot be explained by Alpine Fault displacement. Furthermore, our results suggest that if extinctions resulting from glaciations played a role in the origin of the central endemism gap, their impact was less than might be presumed on the basis of the distribution of taxa as they are currently defined. The diversification of Chionochloa and a number of New Zealand plant groups, such as Ranunculus, was contemporaneous with the initiation of the uplift of the Southern Alps. In contrast to patterns of diversifications within the alpine regions typical of the hyperdiverse Andes, exclusively alpine species in New Zealand arose independently from ancestors distributed in more lowland areas. Similarly, habitat specialists in Chionochloa arose independently from more generalist ancestors. Thus, although diversification in these groups may have been stimulated by mountain building and Pleistocene climatic oscillations, cladogenesis did not occur within the high alpine habitat itself.  相似文献   

9.
In this paper, we review cultural history, mariculture and taxonomic work to date for Porphyra sensu lato (bladed Bangiales) in China. The bladed Bangiales are a red seaweed group with high species biodiversity and economic value. In China, species occur along the length of the coast and are highly integrated into the country’s culture. Chinese people have used the bladed Bangiales as food and pharmaceuticals for about 1700 years with many references to these seaweeds in ancient books. The mariculture of bladed Bangiales in China also has a long history and an industry has been established based on some species, notably Pyropia yezoensis. The scientific study of the taxonomy of the bladed Bangiales in China began in the late 1920s and to date, based on morphological identification, 25 species and five varieties have been recorded for China, of which 12 species are considered to be endemic to the country. The majority of species have distribution data showing evidence of possible changes due to increasing water temperatures along the coast. The global biodiversity of the bladed Bangiales has been revealed using molecular approaches. This points to the need for molecular taxonomy of Chinese material to document species diversity and distribution, particularly as it includes the wild stocks for seaweed cultivation and because coastal habitats are increasingly impacted by the increasing human population and an expanding mariculture industry. There is a considerable body of literature on the bladed Bangiales in China, but much of it is Chinese and in obscure publications, so we review it here for the benefit of readers worldwide.  相似文献   

10.
Foliose species of the Bangiales (Porphyra sensu lato) have a long history of study in the N Atlantic, but there are still regions, especially in the northern parts of the N Atlantic that need more attention. A molecular study using rbcL and cox1 sequences was undertaken to assess the diversity of foliose Bangiales species in Iceland and the Faroe Islands. Herbarium collections from the intertidal and subtidal of Iceland (summer and winter) and the Faroe Islands (all seasons) revealed a total of 13 species (11 common to both areas), which were referred to four of the genera recognized in a recent two-gene global phylogeny. Boreophyllum birdiae, Porphyra dioica, P. linearis, P. purpurea, P. umbilicalis, Pyropialeucosticta’ A, Pyropia njordii Mols-Mortensen, J. Brodie & Neefus, sp. nov., Wildemania amplissima and W. miniata were common to both areas, while Pyropia thulaea and Wildemania abyssicola (Kjellman) A. Mols-Mortensen & J. Brodie, comb. nov. (=Porphyra abyssicola Kjellman) were reported from Iceland but not from the Faroe Islands; Porphyra sp. FO and Pyropia elongata were reported from the Faroe Islands but not from Iceland. Boreophyllum birdiae is reported for the first time for Iceland and Porphyra sp. FO is reported for the first time for the Faroe Islands. Pyropia njordii is described from the Faroe Islands and is also recorded for Iceland, Greenland, New England, USA and Nova Scotia, Canada. A total of 25 foliose Bangiales species are now reported from the N Atlantic and these results demonstrate the importance of investigating as many areas as possible to reach a more complete understanding of species diversity and distribution.  相似文献   

11.
Aim To report analyses and propose hypotheses of adaptive radiation that explain distributional patterns of the alpine genus Pachycladon Hook.f. – a morphologically diverse genus from New Zealand closely related to Arabidopsis thaliana. Location South Island, New Zealand. Methods Morphological and nrDNA ITS sequence phylogenies were generated for Pachycladon. An analysis is presented of species distributional patterns and attributes. Results Phylogenetic analyses of morphological characters and nrDNA ITS sequence data were found to be congruent in supporting three New Zealand clades for Pachycladon. Monophyletic groups identified within the genus are geographically distinct and are associated with different geological parent materials. Distribution maps, latitude and altitude range, and data on geological parent material are presented for the nine named and one unnamed species of Pachycladon from New Zealand. Main conclusions (a) Panbiogeographic hypotheses accounting for the origin and present‐day distribution of Pachycladon in New Zealand are not supported.
(b) Species diversity and distributions of Pachycladon are explained by a Late Tertiary–Quaternary adaptive radiation associated with increasing specialization to geological substrates. Pachycladon cheesemanii Heenan & A.D.Mitch. is morphologically similar to the closest overseas relatives. It is a geological generalist and has wide latitudinal and altitudinal ranges, and we suggest it resembles the ancestral form of the genus in New Zealand. Pachycladon novae‐zelandiae (Hook.f.) Hook.f. and P. wallii (Carse) Heenan & A.D.Mitch. are a southern South Island group that predominantly occurs on Haast Schist, are polycarpic, have lobed leaves, and lateral inflorescences. Pachycladon enysii (Cheeseman) Heenan & A.D.Mitch., P. fastigiata (Hook.f.) Heenan & A.D.Mitch., and P. stellata (Allan) Heenan & A.D.Mitch. are restricted to greywacke in the eastern South Island, and are facultatively monocarpic, have serrate leaves, and stout terminal inflorescenes.
(c) Present distributions of Pachycladon species may relate to Pleistocene climate change. Pachycladon enysii reaches the highest altitude of New Zealand species of Pachycladon and is most common in the Southern Alps in Canterbury. We propose that this species survived on nunataks at the height of the last glaciation. In contrast, P. fastigiata grows at a lower altitude and is absent from the high mountains of the Southern Alps. We suggest it was extirpated from this area during the last glaciation.  相似文献   

12.
New Zealand taxa from the Orthopteran family Anostostomatidae have been shown to consist of three broad groups, Hemiandrus (ground weta), Anisoura/Motuweta (tusked weta) and Hemideina-Deinacrida (tree-giant weta). The family is also present in Australia and New Caledonia, the nearest large land masses to New Zealand. All genera are endemic to their respective countries except Hemiandrus that occurs in New Zealand and Australia. We used nuclear and mitochondrial DNA sequence data to study within genera and among species-level genetic diversity within New Zealand and to examine phylogenetic relationships of taxa in Australasia. We found the Anostostomatidae to be monophyletic within Ensifera, and justifiably distinguished from the Stenopelmatidae among which they were formerly placed. However, the New Zealand Anostostomatidae are not monophyletic with respect to Australian and New Caledonian species in our analyses. Two of the New Zealand groups have closer allies in Australia and one in New Caledonia. We carried out maximum-likelihood and Bayesian analyses to reveal several well supported subgroupings. Our analysis included the most extensive sampling to date of Hemiandrus species and indicate that Australian and New Zealand Hemiandrus are not monophyletic. We used molecular dating approaches to test the plausibility of alternative biogeographic hypotheses for the origin of the New Zealand anostostomatid fauna and found support for divergence of the main clades at, or shortly after, Gondwanan break-up, and dispersal across the Tasman much more recently.  相似文献   

13.
Five new species of Crotonia from New Zealand ( C. cervicorna, C. cupulata, C. longibulbula, C. tuberculata and C. reticulata ) are described as new, and two species ( C. cophinana (Michael 1908) and C. caudatis (Hammer 1966)) are redescribed. Five species groups of the genus are characterized and a key to the adequately described species of the world is presented.  相似文献   

14.
Greenland is a continental island in the northern part of the North Atlantic where the foliose Bangiales flora is poorly known. It is an important area for the study of algal biogeography because of the region’s glacial history, in which Greenland has been alternately exposed to or isolated from the North Pacific via the Bering Strait. A molecular study using 3′ rbcL + 5′ rbcL–S sequences was undertaken to assess the diversity of foliose Bangiales on the west coast of Greenland and rbcL sequences were used to study the Greenland flora in a larger phylogenetic and floristic context. New and historic collections document seven species in four genera from the west coast of Greenland. All species had a close link to North Pacific species, being either conspecific with them or North Atlantic–North Pacific vicariant counterparts.  相似文献   

15.
Kaiwhekea katiki gen. et sp. nov. represents the first described cryptoclidid plesiosaurian from New Zealand. It is one of the largest cryptoclidids known, at a length of over 6.5 m, and represents the third reported genus of austral Late Cretaceous cryptoclidids. Kaiwhekea katiki is from siltstones of the Katiki Formation, upper Haumurian Stage (Cenomanian–Maastrichtian; c. 69–70 Ma) of coastal Otago, South Island, New Zealand. In the Late Cretaceous, the locality lay close to the polar circle. The holotype and only known specimen is an articulated skeleton with skull, preserved mostly as natural molds, but which lacks the forelimbs and pectoral girdle. The skull is relatively large and possesses several distinct characters, including a substantial, deep, jugal. There are about 43 upper and 42 lower teeth in each jaw quadrant; all are homodont, slim, and slightly recurved, lacking prominent ornament. Kaiwhekea probably took single soft-bodied prey. Based on cranial structure, it clearly belongs with the Cryptoclididae, but is not certainly close to the southern Late Cretaceous cryptoclidids Morturneria (Seymour Island, Antarctica) and Aristonectes (Chile, Argentina).  相似文献   

16.
Aim Biogeographers have long been intrigued by New Zealand’s biota due to its unique combination of typical ‘continental’ and ‘island’ characteristics. The New Zealand plateau rifted from the former supercontinent Gondwana c. 80 Ma, and has been isolated from other land masses ever since. Therefore, the flora and fauna of New Zealand include lineages that are Gondwanan in origin, but also include a very large number of endemics. In this study, we analyse the evolutionary relationships of three genera of mite harvestmen (Arachnida, Opiliones, Cyphophthalmi) endemic to New Zealand, both to each other and to their temperate Gondwanan relatives found in Australia, Chile, Sri Lanka and South Africa. Location New Zealand (North Island, South Island and Stewart Island). Methods A total of 94 specimens of the family Pettalidae in the suborder Cyphophthalmi were studied, representing 31 species and subspecies belonging to three endemic genera from New Zealand (Aoraki, Neopurcellia and Rakaia) plus six other members of the family from Chile, South Africa, Sri Lanka and Australia. The phylogeny of these taxa was constructed using morphological and molecular data from five nuclear and mitochondrial genes (18S rRNA, 28S rRNA, 16S rRNA, cytochrome c oxidase subunit I and histone H3, totalling c. 5 kb), which were analysed using dynamic as well as static homology under a variety of optimality criteria. Results The results showed that each of the three New Zealand cyphophthalmid genera is monophyletic, and occupies a distinct geographical region within the archipelago, grossly corresponding to palaeogeographical regions. All three genera of New Zealand mite harvestmen fall within the family Pettalidae with a classic temperate Gondwanan distribution, but they do not render any other genera paraphyletic. Main conclusions Our study shows that New Zealand’s three genera of mite harvestmen are unequivocally related to other members of the temperate Gondwanan family Pettalidae. Monophyly of each genus contradicts the idea of recent dispersal to New Zealand. Within New Zealand, striking biogeographical patterns are apparent in this group of short‐range endemics, particularly in the South Island. These patterns are interpreted in the light of New Zealand’s turbulent geological history and present‐day patterns of forest cover.  相似文献   

17.
We have assessed the utility of a single-copy nuclear locus and mitochondrial DNA (mtDNA) in a phylogeographic study of the New Zealand stick insect Niveaphasma annulata (Hutton). We amplified sequences from the mitochondrial cytochrome oxidase subunit I (COI) gene and the single-copy nuclear gene elongation factor-1α (EF1α) from 97 individuals. Allelic phase at the EF1α locus was determined using Denaturing Gradient Gel Electrophoresis. Phylogenetic analyses showed broad congruence between the geographic distribution of three major COI clades and EF1α alleles, which suggested that the phylogenetic patterns reflect population history rather than lineage sorting. However, the geographic boundaries of these clades were not always in exact agreement between the two loci. Our data indicate that Niveaphasma annulata was most likely separated into a number of refugia during Pleistocene glacial advances. Subsequent to glacial retreat these refugial populations have expanded and now form a number of zones of secondary contact. We contrast these patterns with those observed from other New Zealand taxa. Our study offers compelling evidence for the use of nuclear genes alongside mtDNA for future phylogeographic studies.  相似文献   

18.
Aim The New Zealand avifauna includes lineages that lack close relatives elsewhere and have low diversity, characteristics sometimes ascribed to long geographic isolation. However, extinction at the population and species levels could yield the same pattern. A prominent example is the ecologically important pigeon genus Hemiphaga. In this study, we examined the population structure and phylogeography of Hemiphaga across islands in the region. Location New Zealand, Chatham Islands and Norfolk Island. Methods Mitochondrial DNA was sequenced for all species of the genus Hemiphaga. Sixty‐seven individuals from mainland New Zealand (Hemiphaga novaeseelandiae novaeseelandiae), six of the Chatham Islands sister species (Hemiphaga chathamensis), and three of the extinct Norfolk Island subspecies (Hemiphaga novaeseelandiae spadicea) were included in this study. Novel D‐loop and cytochrome b primers were designed to amplify DNA from museum samples. Additionally, five other mitochondrial genes were used to examine placement of the phylogenetic root. Results Analyses of mitochondrial DNA sequences revealed three Hemiphaga clades, consistent with the allopatric populations of recognized (sub)species on oceanic islands. Of the 23 D‐loop haplotypes among 67 New Zealand pigeons (Hemiphaga n. novaeseelandiae), 19 haplotypes were singletons and one haplotype was common and widespread. Population genetic diversity was shallow within and between New Zealand populations, indicating range expansion with high inter‐population exchange. Tentative rooting of the Hemiphaga clade with cyt b data indicates exchange between mainland New Zealand and the Chatham Islands prior to colonization of Norfolk Island. We found low genetic divergence between populations on New Zealand, the Chatham Islands and Norfolk Island, but deep phylogenetic divergence from the closest living relatives of Hemiphaga. Main conclusions The data are consistent with the hypothesis of population reduction during the Pleistocene and subsequent expansion from forest refugia. Observed mobility of Hemiphaga when feeding helps explain the shallow diversity among populations on islands separated by many hundreds of kilometres of ocean. Together with comparison of distribution patterns observed among birds of the New Zealand region, these data suggest that endemicity might represent not long occupancy of an area, but descent from geologically recent colonizations. We consider the role of lineage pruning in creating the impression of old endemicity.  相似文献   

19.
Abstract The amphibian fauna of New Zealand consists of three native species (Leiopelma spp.), and three Litoria species introduced from Australia in the last 140 years. We conducted a molecular phylogeographical study that aimed to identify the Australian origins of two species, Litoria aurea and Litoria raniformis. We used partial sequences of the mitochondrial cytochrome oxidase I (cox1) gene from 59 specimens sampled from across the range of both species to identify the probable source populations for the New Zealand introductions, and to describe the current genetic diversity among New Zealand Litoria populations. Our genetic data suggest that L. aurea was introduced into the North Island of New Zealand from two regions in Australia, once from the northern part of coastal New South Wales and once from the southern part of coastal New South Wales. Our data indicate that L. raniformis introductions originated from the Melbourne region of southern Victoria and once established in the South Island of New Zealand, the species subsequently spread throughout both islands. In addition, we found a distinct haplotype in L. raniformis from Tasmania that strongly suggests, contrary to earlier reports, that this species was not introduced into New Zealand from Tasmania. Finally, we identified two very distinctive mitochondrial lineages of L. raniformis within the mainland Australia distribution, which may be previously unrecognized species.  相似文献   

20.
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