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1.
Polysiphonia sensu lato comprises approximately 200 species, which are currently assigned to several different genera. To date, one of these genera, namely, Polysiphonia, has been reported to have 17 species. Here, we describe for the first time P. freshwateri sp. nov. and P. koreana sp. nov. from Uljin and Ulleung Island, Korea, based on morphological and molecular evidence. Polysiphonia freshwateri sp. nov. and P. koreana sp. nov. are characterized by having the typical Polysiphonia features. Polysiphonia freshwateri sp. nov. is further characterized by having abundant trichoblasts, conspicuous scar cells, and tetrasporangia arranged in spiral series. Polysiphonia koreana sp. nov. is further characterized by having very scarce scar cells placed between two pericentral cells, from which cicatrigenous branches arise. The results of our rbcL sequence analyses support the taxonomic placement of P. freshwateri sp. nov. and P. koreana sp. nov. within Polysiphonia.  相似文献   

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Caloglossa species are widely distributed in mangroves and salt marshes around the world and their life history patterns are being investigated in laboratory culture. In Australia all isolates of C. monosticha, C. postiae and C. ogasawaraensis have Polysiphonia‐type (P‐type) sexual life histories. Among the 70 C. leprieurii isolates from Australia and New Zealand P‐type sexual reproduction also is dominant. However, ten isolates of C. leprieurii from the Spencer Gulf and the Gulf of St. Vincent in South Australia give rise to successive tetrasporphyte generations without gametophytes. Moreover, one isolate from Queensland is asexual. Only one South Australia isolate, obtained from Lake Alexandrina at the mouth of the Murray River, is sexual. South Australia and Pacific Mexico are two regions in which asexual reproduction is dominant. In another mangrove dwelling red alga Bostrychia moritiziana (Rhodomelaceae) non‐sexual reproduction also is frequent in Australia, New Caledonia and Bali (Indonesia). This asexual reproductive pattern of tetrasporophytic recycling appears to have arisen independently among individual populations of various red algal species in different regions. Investigations are underway on the molecular phylogeny of the Caloglossa leprieurii isolates.  相似文献   

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The life history of an isolate of Polysiphonia denudata (Dillw.) Kütz. from Texas is shown by means of cultural studies to be of the Polysiphonia-type (a sequence of gametophytic, carposporophytic and tetrasporophytic phases in which the former and latter are morphologically similar). The effects of light intensity and temperature on the isolate have been investigated by a cross-gradient culture apparatus; a series of incubators was used to investigate the effects of variations in daylength on the growth and reproduction of the species. Seasonal observations were conducted on growth and reproduction of the species in nature and an attempt is made to explain the observed distribution of the species on the basis of the cultural study.  相似文献   

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Sequence data generated during a Canadian barcode survey (COI-5P) of the tribes Polysiphonieae and Streblocladieae, a large and taxonomically challenging group of red algae, revealed significant taxonomic confusion and hidden species diversity. Polysiphonia pacifica Hollenberg, P. paniculata Montagne, P. stricta (Dillwyn) Greville and Vertebrata fucoides (Hudson) Kuntze were all complexes of two or more genetically distinct yet overlooked species. One variety of P. pacifica was elevated to the rank of species as P. determinata (Hollenberg) Savoie & Saunders, stat. nov. Several new additions to the Canadian flora were recorded including P. kapraunii Stuercke & Freshwater and P. morrowii Harvey. Subsequent multi-gene (COI-5P, LSU and rbcL) phylogenetic analyses confirmed that the genus Polysiphonia Greville was polyphyletic, and currently assigned species resolved with many other genera. Polysiphonia sensu stricto was restricted to a group of species that formed a monophyletic lineage with the type, Polysiphonia stricta. Carradoriella P.C.Silva was resurrected based on the South African species Carradoriella virgata (C.Agardh) P.C.Silva. Species previously attributed to Polysiphonia were transferred to Carradoriella, Leptosiphonia and Vertebrata as well as to three new genera described here: Acanthosiphonia gen. nov., based on A. echinata (Harvey) comb. nov.; Eutrichosiphonia gen. nov. for E. confusa (Hollenberg) comb. nov. and E. sabulosia (B.Kim & M.S.Kim) comb. nov.; and Kapraunia gen. nov., which includes K. schneideri (Stuercke & Freshwater) comb. nov. and three additional species.  相似文献   

6.
The 22 species of the genus Micrambe Thomson known from South Africa are analyzed and revised. Micrambe danielssoni sp. nov is described. Following a detailed study of the type material in different entomological collections, the status of two taxa is revised and two new synonymies are proposed: Micrambe kolbei Grouvelle 1908, syn. nov. for Micrambe minuta Grouvelle 1908, and Micrambe similis Bruce 1957, syn. nov. for Micrambe peringueyi Grouvelle 1908. A lectotypus is designated for one taxon: Micrambe capensis (Redtenbacher 1867). A key to all the species occurring in South Africa is presented.  相似文献   

7.
We describe two new species of the nematomorph genus Acutogordius, A. sulawensis from Sulawesi and A. protectus from Madagascar. For comparative reasons, the other known species are briefly described and discussed. The genus Acutogordius now comprises nine species regarded as valid. They are distributed on the entire southern hemisphere, from South and Central America over Africa and South‐east Asia to Australia. The three male specimens of Acutogordius protectus differ in the shape of a cuticular structure, the postcloacal crescent, which has implications for the potential of this character as a taxonomic tool.  相似文献   

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The genus Skidmorella Johnson, previously known only from the South Pacific islands, is discovered in Japan. The type species, Skidmorella magnifica Johnson, is confirmed from Japan as the first record of the species other than the type locality. In addition, two new species, Skidmorella amamiana sp. nov. and Skidmorella quadrisulucia sp. nov., are described from the Ryukyus, Japan. Phylogenetic relationships of the genus Skidmorella and its allies are discussed on the basis of their morphological characters.  相似文献   

10.
R.J. Kluge  A.J. Gordon 《BioControl》2004,49(3):341-355
The hakea bud weevil, Dicomada rufa (Curculionidae), is a promising candidate for the biological control of the weed Hakea sericea (Proteaceae) in South Africa. Because D. rufa could not be successfully cultured on potted plants in quarantine, most of theconventional methods for host range determination were not suitable. A type of open-field testing method, the fixed plot survey method, was developed to show that D. rufa is host specific to H. sericea. The trial was conducted in three 1–2 ha plots at three localities in New SouthWales, Australia, involving 41 test plantspecies. This result was combined with otherconventional considerations to apply for therelease of D. rufa in South Africa. Theseincluded a multiple choice feeding trial inquarantine in South Africa, during which 10test species from seven genera of South AfricanProteaceae were not accepted for feeding. AllSouth African Proteaceae, except Brabejumstellatifolium, are phylogenetically distinctfrom H. sericea. Also, there are norecords of D. rufa interacting withcommercially important plants in Australia,including commercially cultivated South AfricanProteaceae. Dicomada rufa adult andlarval feeding destroys buds, flowers, smallfruits and succulent shoots. It is expectedthat this damage will supplement that of thetwo seed-feeding biological control agentsalready established in South Africa and furtherreduce the reproductive potential of the weed,particularly that of young plants regeneratingafter fires. Without compromising safety, thefixed plot survey method may also contribute toreducing the time and cost normally associatedwith conventional host specificity testing.  相似文献   

11.
Artemisia pattersonii and A. scopulorum are closely related species of alpine sages endemic to the Rocky Mountains. The species are compared morphologically, ecologically and especially karyologically. Artemisia pattersonii has a chromosome number of n = 7, 2n = 14, which is presently unique in the genus. The karyotype of A. pattersonii is contrasted to its nearest putative relative, A. scopulorum (n = 9, 2n = 18), in order to determine if A. pattersonii might be derived from A. scopulorum through aneuploid reduction; however, the cytological evidence is inconclusive. Possibly these two species are not as closely related as believed previous'y and the nearest relatives of each might occur in north-central Asia.  相似文献   

12.
We used a molecular phylogenetic approach to investigate species delimitations and diversification in the mussel drills of the Ocinebrina edwardsii complex by means of a combination of nuclear (internal transcribed spacer 2, ITS2) and mitochondrial [cytochrome oxidase subunit I (COI) and 16S] sequences. Our sample included 243 specimens ascribed to seven currently accepted species from 51 sites. Five of the samples were from either the type locality of a nominal species or a close nearby locality (O. edwardsii from Corsica, O. carmelae and O. piantonii from the Kerkennah Islands, O. hispidula from the Gulf of Gabès and O. leukos from the Canary Islands), one from the inferred original locality (O. ingloria from Venice Lagoon), and specimens assigned in the recent literature to O. nicolai. We used a combination of distance‐ and tree‐based species delimitation methods to identify Molecular Operational Taxonomic Units (MOTUs) to compare with the a priori species identifications. The consensus tree obtained by BEAST on the COI alignment allows the recognition of several distinct clades supported by the three species delimitation methods employed. The eight‐MOTUs scenario, shared by the Automatic Barcode Gap Discovery (ABGD) and Generalized Mixed Yule‐Coalescent (GMYC) methods, comprises the following major clades: clade A contains the south Tunisian species Ocinebrina piantonii Cecalupo, Buzzurro & Mariani from which the sympatric taxon O. carmelae Cecalupo, Buzzurro & Mariani (new synonym) cannot be separated; clades B and C bring together all populations from the Aegean Sea and some from the Ionian Sea, respectively; clade D groups, on the one hand, the south Tunisian samples morphologically assigned to O. hispidula Pallary and, on the other, Atlantic and Alboran Sea samples (including the Canarian taxon O. leukos Houart); clade E includes a sample from the type locality of O. edwardsii and several samples from the Tyrrhenian Sea; clades F and G correspond to a few samples from the Venice Lagoon and the Tyrrhenian Sea, respectively; clade H groups the bulk of samples from the Adriatic Sea, including samples from the Venice Lagoon morphologically identified as Ocinebrina ingloria (Crosse), and some from the Ionian Sea. No final conclusions could be reached to reconcile the currently recognized morphological taxa with the clades suggested by the COI data. The geographical structure proposed by the mitochondrial markers is similar to that found in other marine invertebrates and partially corresponds to the species defined by shell characters. We propose here a framework for the revision of the Ocinebrina edwardsii species complex, suggesting a geographical pattern for the diversification of this group in the studied area. © 2013 The Linnean Society of London  相似文献   

13.
We have undertaken a comprehensive, molecular‐assisted alpha‐taxonomic examination of the rhodophyte family Liagoraceae sensu lato, a group that has not previously been targeted for molecular studies in the western Atlantic. Sequence data from three molecular markers indicate that in Bermuda alone there are 10 species in nine different genera. These include the addition of three genera to the flora — Hommersandiophycus, Trichogloeopsis, and Yamadaella. Liagora pectinata, a species with a type locality in Bermuda, is phylogenetically allied with Indo‐Pacific species of Hommersandiophycus, and the species historically reported as L. ceranoides for the islands is morphologically and genetically distinct from that taxon, and is herein described as L. nesophila sp. nov. Molecular sequence data have also uncovered the Indo‐Pacific L. mannarensis in Bermuda, a long‐distance new western Atlantic record. DNA sequences of Trichogloeopsis pedicellata from the type locality (Bahamas) match with local specimens demonstrating its presence in Bermuda. We described Yamadaella grassyi sp. nov. from Bermuda, a species phylogenetically and morphologically distinct from the generitype, Y. caenomyce of the Indo‐Pacific. Our data also indicated a single species each of Ganonema, Gloiocallis, Helminthocladia, Titanophycus, and Trichogloea in the flora.  相似文献   

14.
Acacia saligna is a species complex that has become invasive in a number of countries worldwide where it has caused substantial environmental and economic impacts. Understanding genetic and other factors contributing to its success may allow managers to limit future invasions of closely related species. We used three molecular markers to compare the introduced range (South Africa) to the native range (Western Australia). Nuclear markers showed that invasive populations are divergent from native populations and most closely related to a cultivated population in Western Australia. We also found incongruence between nuclear and chloroplast data that, together with the long history of cultivation of the species, suggest that introgressive hybridization (coupled with chloroplast capture) may have occurred within A. saligna. While we could not definitively prove introgression, the genetic distance between cultivated and native A. saligna populations was comparable to known interspecific divergences among other Acacia species. Therefore, cultivation, multiple large‐scale introductions and possibly introgressive hybridization have rapidly given rise to the divergent genetic entity present in South Africa. This may explain the known global variation in invasiveness and inaccuracy of native bioclimatic models in predicting potential distributions.  相似文献   

15.
A new family of Laniatores, Gerdesiidae fam. nov., is proposed based on molecular and morphological evidence. Data also indicate that this new family is the sister family of Tricommatidae. Gerdesiidae fam. nov. has a disjunct distribution, occurring in northern South America (Peru, Brazilian Amazon) and at a spot in south‐eastern Brazil (Minas Gerais State). The new family is composed of two genera: Gerdesius Roewer, 1952 (type genus) and G onycranaus gen. nov. (type species G onycranaus androgynus sp. nov. ). We propose the synonymy of Huralvioides H. Soares, 1970 with Gerdesius Roewer, 1952 based on molecular and morphological evidence. Three new species are described: G erdesius mapinguari sp. nov. (type locality: Brazil, Amazonas, Manaus, Reserva Km 41); G onycranaus androgynus sp. nov. (type locality: Brazil, Minas Gerais, Conceição do Mato Dentro); and an obligate cave‐dwelling species, G onycranaus pluto sp. nov. (type locality: Brazil, Minas Gerais, Morro do Pilar). © 2015 The Linnean Society of London  相似文献   

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The fern genus Cyrtomium (Dryopteridaceae) in Africa and Madagascar is reviewed. Until now, a single Cyrtomium species ascribed to either C. caryotideum or C. micropterum (the latter often considered to be a variety of the former) was recognized for the region. This study shows that three Cyrtomium species occur in the region. One, C. falcatum, is not native to the African or Madagascan region, but has become naturalized in various parts of South Africa and Réunion. Two, formerly considered as a single taxon and confused with C. caryotideum and Indian forms thereof, are described as new – C. luctuosum from Madagascar, East, West and South Africa and C. pseudocaryotideum from South Africa. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 449–465.  相似文献   

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Phylogenetic analysis of noncoding trnL plastid DNA sequences and morphological data for 43 species of Zygophylloideae, representing most of the morphological and geographical variation in the subfamily, indicates that the currently recognised genera Augea (monotypic, southern Africa), Tetraena (monotypic, China), and Fagonia (c. 30 species, widespread), are embedded in Zygophyllum (c. 150 species, widespread). A generic classification based on six monophyletic and morphologically distinctive entities is proposed: Roepera with c. 60 species in Australia and southern Africa, Zygophyllum with c. 50 species in Asia, Tetraena with c. 40 species in Africa and Asia, Augea with a single species in southern Africa, Melocarpum with two species in the Horn of Africa region, and Fagonia with c. 30 species in both the Old and the New World. Scanning electron microscopy studies of testa structure provided important characters for the delimitation of some genera. New combinations (61) are made in Roepera, a resurrected genus originally described from Australia, one new name is proposed in Zygophyllum, 35 new combinations are made in Tetraena, and two new combinations are made in Melocarpum (previously Zygophyllum sect. Melocarpum).  相似文献   

20.
Albuca tenuifolia Baker was described and illustrated in 1872 from South African material sent by Peter MacOwan to William Wilson Saunders in England, without a precise locality. Since then this species has been cited in later works although with many uncertainties. In addition, no type has been designated for this taxon. After field work in the Great Escarpment in South Africa, some populations of A. tenuifolia have been rediscovered growing in rocky places at high altitude. Data on morphology, ecology, and distribution are reported, and a lectotype and epitype are designated to fix the use of the name. Affinities with other species are also discussed.  相似文献   

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