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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Origin and biogeography of New Zealand Craspedia (Compositae: Gnaphalieae)

Ford, Kerry January 2004 (has links)
Craspedia (Compositae: Gnaphalieae) is a genus of 23 species found only in Australia and New Zealand. New Zealand species of Craspedia have confusing and continuous character variation, with boundaries between species often indistinct and relationships difficult to elucidate. Taxonomic treatments in the genus so far have been regionally based, with the result that species between New Zealand and Australia have not been adequately compared. Phylogenetic analyses of ITS, ETS and psbA-trnH non-coding spacers show that New Zealand Craspedia is a monophyletic group nested within Australian Craspedia. This is consistent with a jump-dispersal event from Australia to New Zealand across the Tasman Sea. The New Zealand lineage is identified as sister to one of two Australian lineages, which consists of mainly subalpine and alpine species found on the main divide of south eastern Australia and in Tasmania. An estimate of when New Zealand Craspedia diverged, using ITS substitution rates from other mainland/island disjunctions in Compositae, gave an approximate date of between 650,000 and 325,000 years ago. This is consistent with the New Zealand fossil pollen record, and with other molecular studies, in suggesting that the Pleistocene, a period of mountain building and climate change, has been an important factor in the evolution of the New Zealand herbaceous flora. The two Australian lineages have not previously been recognised based on morphology and it is suggested they represent two independent species radiations into the Australian alpine zone. Although the New Zealand clade is only partly resolved, the phylogenetic analyses of ITS and ETS indicate that some relationships are incongruent with those previously suggested by morphology and current species boundaries.
32

O gênero Sida L. (Malvaceae) no estado de Pernambuco, Brasil / The genus Sida L. (Malvaceae) in Pernambuco State, Brazil

BRANDÃO NETO, José Lourenço Soares 14 February 2014 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-06-21T13:26:54Z No. of bitstreams: 1 Jose Lourenco Soares Brandao Neto.pdf: 3937851 bytes, checksum: 6e8aeda8151916253486904a2082c37e (MD5) / Made available in DSpace on 2016-06-21T13:26:54Z (GMT). No. of bitstreams: 1 Jose Lourenco Soares Brandao Neto.pdf: 3937851 bytes, checksum: 6e8aeda8151916253486904a2082c37e (MD5) Previous issue date: 2014-02-14 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Several taxa of subfamily Malvoideae, Malvaceae, presents complex classification problem. Sida L. is inserted in Malvea tribe, comprising about 200 species cosmopolitan and pantropical, whose biodiversity centres are the African and American continents, composed of twelve sections currently accepted. In Brazil, are found approximately 90 species. This paper aims to develop a taxonomic study of the genus Sida L. occurring in Pernambuco, seeking, through the variability characters interpretation, clarify their limits interspecific more complex. For production data, samples were collected in several municipalities and phytogeographic regions of the state, as well as periodic reviews of collected and herborized specimens, especially those of Pernambuco, and consultations with photographs of type collections from herbaria national and international complemented by research literature and protologues. About 25 species were referred to Pernambuco. From further studies, were found about sixteen species of the genus to the state: Sida acuta Burm.f., S. angustissima A.St.-Hil., S. brittonii León, S.cerradoensis Krapov., S. ciliaris L., S. cordifolia L., S. galheirensis Ulbr., S. glomerata Cav., S. jussieana DC, S. linifolia Cav., S. planicaulis Cav., S.rhombifolia L., S. setosa Mart. ex Colla, S. spinosa L., S.ulei Ulbr. and S. urens L. Identification key are supplied, as well as descriptions, distribution maps, comments on relationships and geographic distribution and species`s illustrations of morphological characters most relevant to species delimitation. / ários táxons da subfamília Malvoideae, Malvaceae, apresentam complexos problemas de classificação infragenérica. Sida L. está inserido na tribo Malvea, compreendendo cerca de 200 espécies cosmopolitas e pantropicais, cujos centros de biodiversidade são os continentes africanos e americano, composto por doze seções atualmente aceitas. Para o Brasil são encontradas aproximadamente 90 espécies. Este trabalho objetivou a elaboração de estudo taxonômico do gênero Sida L. ocorrente no Estado de Pernambuco, buscando, através da interpretação da variabilidade de seus caracteres, esclarecer seus limites interespecíficos mais complexos. Para a fomentação dos dados, foram realizadas coletas ao longo de boa parte dos municípios e regiões fitogeográficas do estado, bem como análises periódicas aos espécimes coletados e herborizados, sobretudo aqueles de Pernambuco, e consultas a imagens de coleções tipo provenientes de herbários nacionais e internacionais, complementada por pesquisa em literatura especializada e protólogos. Cerca de 25 espécies eram referidas para Pernambuco. A partir de estudos mais aprofundados, foram encontradas dezesseis espécies do gênero para o estado: Sida acuta Burm.f., S. angustissima A.St.-Hil., S. brittonii León, S.cerradoensis Krapov., S. ciliaris L., S. cordifolia L., S. galheirensis Ulbr., S. glomerata Cav., S. jussieana DC, S. linifolia Cav., S. planicaulis Cav., S.rhombifolia L., S. setosa Mart. ex Colla, S. spinosa L., S.ulei Ulbr. e S. urens L. São apresentadas chave de identificação para as espécies, comentários e mapas sobre sua distribuição geográfica e afinidades, bem como ilustrações morfológicas dos caracteres mais relevantes para a delimitação das espécies.
33

Revisão taxonômica e análise cladística do gênero Odontopeltis Pocock, 1894 (Diplopoda, Polydesmida, Chelodesmidae) / Taxonomic review and cladistic analysis of the genus Odontopeltis Pocock, 1894 (Diplopoda; Polydesmida; Chelodesmidae)

João Paulo Peixoto Pena Barbosa 27 June 2011 (has links)
Uma análise cladística baseada em parcimônia é utilizada para testar o monofiletismo do gênero Odontopeltis e suas relações com outras espécies de gêneros anteriormente relacionados. A matriz de dados compreende 15 terminais e 47 caracteres. A análise cladística com pesagem implícita de caracteres de concavidade igual a 2,012 resultou em uma árvore mais parcimoniosa com 99 passos (IC = 58; IR = 73). As seguintes sinapomorfias sustentam o clado Odontopeltis e são propostas como diagnoses para o gênero: (1) Formato do órgão de Tömösvary sub-oval; (2) borda do ozóporo simples; (3) dobras retrolaterais no acropódito; e (4) presença de um par de macro-cerdas delimitando o fim da região pré-femoral e o início da região femoral, no gonopódio. Para padronização das descrições de genitália, foi analisada toda a terminologia do gonopódio dos machos da família Chelodesmidae. O gonopódio dos machos é, então, formado por peças cujas homologias às peças das pernas é incerta: coxa, cânula, região pré-femoral, processo pré-femoral, região femoral e solenômero. Para o gênero Odontopeltis é proposta uma terminologia da genitália à parte, devido às modificações no gonopódio. O gênero é composto por 13 espécies, sendo oito espécies válidas e cinco insertis sedis, sendo elas: Odontopeltis conspersus, O. anchisteus, O. clarazianus, O. giganteus, O. sp. nov. 1, O. sp. nov. 2, O. sp. nov. 3 e O. sp. nov. 4, e as espécies insertis sedis são: O. próxima, O. gracilipes, O. decoloratus, O. borellii e O. balzanii. A tribo Macrocoxodesmini se mostrou parafilética e, portanto, foi desmembrada. A tribo Telonychopodini se manteve monofilética e o gênero Odontopeltis de fato não pertence a esta tribo. / A cladistic analysis based on parsimony is used to test the monophyly of the genus Odontopeltis and its relationship with related genera. The data matrix comprises 15 terminal taxa and 47 characters. The implied weighted analysis, with concavity 2,012, resulted in a 99 steps most parsimonious tree (CI = 58; RI = 73). The following sinapomorphies supports the clade Odontopeltis and are proposed as diagnosis characters for the genus: (1) Tömösvary organ sub-oval shaped; (2) ozopores edge simple; (3) retrolateral rims on acropodite; and (4) presence of macrobristles delimiting the end of the prefemoral region and the beginning of the femoral region, on the gonopods. To standardize the genitalia description, the terminology for the gonopods of the family Chelodesmidae was reviewed. Then, the male gonopods are composed by: coxae, cannula, prefemoral region, prefemoral process, femoral region and solenomere. There is no attempt to relate the homology of legs pieces with gonopod pieces. It\'s proposed a terminology for the gonopods of the genus Odontopeltis due to the modifications on the gonopods. The genus comprises 13 species, where eight are valid species and five are insertis sedis: Odontopeltis conspersus, O. anchisteus, O. clarazianus, O. giganteus, O. sp. nov. 1, O. sp. nov. 2, O. sp. nov. 3 and O. sp. nov. 4, and the insertis sedis species are: O. proxima, O. gracilipes, O. decoloratus, O. borellii and O. balzanii. The Macrocoxodesmini tribe showed as a paraphyletic group and, therefore, was dissolved. The Telonychopodini tribe is monophyletic and the genus Odontopeltis, indeed, do not belong to this tribe.
34

O gênero Hypolepis Bernh. (Dennstaedtiaceae) na América do Sul / The genus Hypolepis Bernh.(Dennstaedtiaceae) in South America

Pedro Bond Schwartsburd 16 April 2012 (has links)
Hypolepis Bernh. é um gênero sub-cosmopolita com ca. 80 táxons, e com pouquíssimos estudos taxonômicos. O presente trabalho trata da revisão taxonômica das espécies ocorrentes na América do Sul, incluindo a Ilha de Cocos (Costa Rica). O mesmo se desenvolveu, principalmente, através do estudo morfológico dos tipos nomenclaturais e de exsicatas oriundas de herbários europeus, sul-americanos e de um neo-zeolandês. Algumas espécies também foram estudadas em campo. Para a América do Sul (incl. Cocos) são aqui reconhecidas 27 espécies, e um total de 31 táxons (espécies, subespécies e variedades). Destas, 11 representam novidades nomenclaturais: H. acantha Schwartsb., H. bogotensis var. glabra H. Karst. ex Schwartsb. & J. Prado, H. flexuosa var. zimmerae Schwartsb. & J. Prado, H. galapagensis Schwartsb. & J. Prado, H. Krameri Schwartsb. et al., H. Paulistana Schwartsb. & J. Prado, H. Pedropaloensis Schwartsb. & J. Prado, H. Rugosula subsp. poeppigiana (Mett.) Schwartsb. & J. Prado, H. Rugosula subsp. pradoana Schwartsb., H. Stolonifera var. nebularis Schwartsb., e H. Trinationalis Schwartsb. Grande parte dos táxons foram re-circunscritos, especialmente H. Flexuosa Sodiro var. flexuosa, H. Mitis Kunze ex Kuhn, H. Poeppigii (Kunze) R.A. Rodr., H. Repens (L.) C. Presl, H. Rigescens (Kunze ex Mart.) T. Moore, e H. Stolonifera Fée var. stolonifera. Foram reconhecidos oito padrões biogeográficos para os táxons: \"neotropical\", \"circum-caribenho\", \"circum-amazônico\", \"Monte Roraima\", \"andino\", \"ilhas\", \"sul-brasileiro\", e \"austral\". Altitudes mínimas e máximas parecem ser fortes fatores limitantes de distribuição. O tratamento taxonômico apresenta chaves de identificação, sinonímias, tipificações, descrição dos táxons, mapas de distribuição, ilustrações, material examinado, e comentários taxonômicos e/ou nomenclaturais. Em adição, são apresentadas breves discussões morfológicas, ecológicas, biogeográficas, de conceitos específicos e infra-específicos de alguns táxons, e de grupos informais de espécies; além de pranchas com secções anatômicas de quatro espécies. / Hypolepis Bernh. is a sub-cosmopolitan genus with ca. 80 taxa, and with few taxonomic studies. The present work deals with the taxonomic revision of the South American species, including the Cocos Island (Costa Rica). It has been based, mainly, on the morphological study of nomenclatural types and exsiccates from European, South American, and New Zealand herbaria. Some species were also studied in nature. For South America (incl. Cocos Island), 27 species are here recognized, and a total of 31 taxa (species, subspecies, and varieties). Among these, 11 represent nomenclatural novelties: H. acanthi Schwartsb., H. bogotensis var. glabra H. Karst. ex Schwartsb. & J. Prado, H. flexuosa var. zimmerae Schwartsb. & J. Prado, H. galapagensis Schwartsb. & J. Prado, H. Krameri Schwartsb. et al., H. Paulistana Schwartsb. & J. Prado, H. Pedropaloensis Schwartsb. & J. Prado, H. Rugosula subsp. poeppigiana (Mett.) Schwartsb. & J. Prado, H. Rugosula subsp. pradoana Schwartsb., H. Stolonifera var. nebularis Schwartsb., and H. Trinationalis Schwartsb. Most taxa were re-circunscribed, especially H. Flexuosa Sodiro var. flexuosa, H. Mitis Kunze ex Kuhn, H. Poeppigii (Kunze) R.A. Rodr., H. Repens (L.) C. Presl, H. Rigescens (Kunze ex Mart.) T. Moore, and H. Stolonifera Fée var. stolonifera. Eight bio-geographical patterns were recognized: \"Neotropical\", \"circum-Caribbean\", \"circum-Amazonian\", \"Mount Roraima\", \"Andean\", \"islanders\", \"southern Brazilian\", and \"Austral\". Minimum and maximum elevations seem to be strong limiting factors of distribution. The taxonomic treatment presents keys to taxa, synonymies, typifications, taxa description, distribution maps, illustrations, studied material, and taxonomic and/or nomenclatural comments. In addition, it is presented short discussions about morphology, ecology, bio-geography, specific/infra-specific concepts of some taxa, and informal groups of species; also, plates with anatomical sections of four species.
35

When Ground Beetles Fly: A Taxonomic Review of the Arboreal, Myrmecophilous Neotropical Genus, Homopterus (Coleoptera: Carabidae: Paussinae) with a new Species Description, Species Diagnoses, and Insights into Species Distributions

Hoover, Angela Marie, Hoover, Angela Marie January 2016 (has links)
A review of the species groups of the Neotropical myrmecophilous genus Homopterus Westwood is presented based on the first molecular phylogenetic analysis of the genus and morphological study of 260 specimens. Two new species groups, the H. subcordatus group and the H. filiko group are erected based on the results of the molecular phylogenetic analysis and morphological analysis. The genus consists of one species known only from Dominican amber, H. hispanolienses Nagel, and thirteen extant species, one of which is described as new: Homopterus filiko n.sp. from Peru. An illustrated dichotomous identification key to species, diagnoses of the species groups and updated distribution maps are provided. The potential of several of the species groups to harbor additional cryptic diversity is discussed.
36

Review of South African genera of the family hexabothriidae price, 1942, parasites of chondrichthyan fishes

Vaughan, David Brendan January 2009 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / The oligonchoinean monogenean family Hexabothriidae Price, 1942 currently consists of approximately 60 valid species, representing 15 genera. Hexabothriids are gill parasites of chondrichthyan fishes (sharks, rays and chimaeras). Some hexabothriid species have been reported as problematic in public aquaria, directly responsible for host pathology and subsequent host mortalities. However, without information on specific hexabothriid species and their host associations, accurate captive management of hexabothriids in public aquaria is hindered. Hexabothriid taxonomy is in a state of confusion. The historic taxonomic restoration of the priority of Hexabothrium sees the beginning of the taxonomic uncertainty of the hexabothriids, and is continued into the present literature particularly among lower-level taxa in Hexabothriidae. In addition, there is currently no consensus for a single accepted morphometric protocol for the discrimination of hexabothriid taxa, which leads to unnecessary ambiguity of character variable nomenclature, measurement and interpretation. A call for stability in the nomenclature and morphometric discrimination of species is therefore proposed. A novel morphometric protocol is tested for the sclerotised haptoral armature, supported by the proteolytic digestion of structures for optimal representation. Character variables, subjected to univariate and multivariate analyses were systematically accepted or rejected based on their potential to discriminating species of Callorhynchocotyle Suriano and Incorvaia, 1986. The hexabothriid genera Callorhynchocotyle and Branchotenthes, represented by South African taxa, are reviewed, using these variables. Four Callorhynchocotyle species and 2 Branchotenthes species are redescribed with the inclusion of some new voucher specimens.
37

Taxonomic Analysis of Marine Actinomycetic Isolates

Haesly, Doran John 08 1900 (has links)
Though this current study was initiated independently and was not a test laboratory for the taxonomic sub-committee's evaluative program, the problem outlined in this treatise was also designed in an effort to test certain characteristics of the actinomycetes of both a biochemical and morphological nature. This problem employed methods that might absolve or establish certain criteria for taxonomic use in the group of actinomycetes.
38

Assessing species richness patterns and conservation threats (due to overharvesting and climate change) in South African Cycads, with emphasis on a population of Encephalartos tranvenosus Stapf and Burt Davy from the Soutpansberg Mountain, Limpopo Province

Bamigboye, Samuel Oloruntoba 18 May 2018 (has links)
PhD (Botany) / Department of Botany / Cycads are regarded as the oldest living seed plants on earth and they have existed for about 300 million years. Ever since the awareness of the existence of this plant group, they have been facing high extinction risk. Currently they are referred to as the most threatened plant group in the world. Many ecological and anthropological forces are promoting extinction crisis of this taxonomic group. Africa is one of the centres of diversity of this plant group with 70% of the total number of the taxa in this group in Africa found in South Africa. Also South Africa is one of the global hotspots for cycads and it contains the third largest number of cycads after Australia and Mexico. Studies have revealed that there have been high threats and extinction risks among the cycad taxa in South Africa. The Soutpansberg Mountain is a major biodiversity hotspot in Limpopo Province in South Africa with high level of flora and fauna taxa. About 3000 vascular plants species are represented on this mountain. Biodiversity on this mountain has been under threat in recent times and there is need to investigate how cycads are facing risk on this mountain. The main focus of this study is to look at the extinction pattern in South African cycads and cycads endemic to Soupandberg Mountain in Limpopo Province in South Africa. v The first objective evaluated all African cycads over a decade using IUCN red list. Data from IUCN 2014 version was used to calculate the percentages of African cycads in each IUCN categories. The results were compared with those presented by Donaldson 2003. They showed that there have been significant decline and increase in extinction of African cycads over this period. It was also discovered that majority of this extinction crisis were trending in South Africa. The second objective used the IUCN red list to evaluate extinction pattern in South African cycads. The percentages of IUCN threat categories of South African cycads was calculated using IUCN red list. ArcGIS was used to construct distribution map for threatened and extinct South African cycads. The study revealed that the proportion of historically Extinct and Critically Endangered cycads is higher in Limpopo, KwaZulu-Natal and Mpumalanga than the rest of the provinces in South Africa. The third objective of this research investigated extinction pattern of Encephalartos transvenosus Stapf & Burtt Davy (Modjadji cycad) on Soutpansberg Mountain. Indigenous knowledge and population ecology approaches were used to determine current threats Modjadji cycads are facing on Soutpansberg Mountain. The results showed that anthropogenic activities have caused a substantial decline of one important unprotected population of this species on Soutpansberg Mountain. / NRF
39

Systematics of subtribe Anthosperminae and the generic affinities of Anthospermum L. and Nenax Gaertn. (Rubiaceae: Anthospermeae)

Nemando, Rangani January 2021 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / The last taxonomic treatment of the subtribe Anthosperminae Benth. (Rubiaceae, Rubioideae, Anthospermeae) was in 1986 by Puff., nevertheless, few attempts have been made to resolve the phylogeny and the inter- and infrageneric relationships within the subtribe. The genera Anthospermum L. (39 species) and Nenax Gaertn. (11 species) are considered the most difficult groups to distinguish. Anthospermum species are widely distributed in Sub-Saharan Africa and Madagascar with the highest concentration of taxa in southern Africa, while Nenax species are restricted to southern Africa, in the south-western Cape Floristic Region. The two genera share common morphological and anatomical characters such as the growth form, presence of hairs on the stem, leaf arrangement, presence of petioles, flowers formation, dehiscence and presence of carpophore in fruits. currently combination of characters, woody shrub, needle-like leaves, few-flowered inflorescence and dioecy are considered unique in Nenax. The most recent phylogenetic analysis based on molecular data indicated insights into generic relationships within the two genera and the subtribe Anthosperminae. The present study focussed on expanding the phylogenetic analysis of Anthospermum, Nenax and other genera within the subtribe, as well as assessing the value of selected morphological and anatomical characters for re-assesing generic circumscriptions. Phylogenetic relationships were analysed using Maximum Parsimony, Maximum Likelihood and Bayesian inference, and a Maximum Clade Credibility tree was produced. These analyses were based on both nuclear (ITS, ETS) and plastid (trnL-f, rps16, rpl32) datasets.
40

New Asian and Nearctic Hypechiniscus species (Heterotardigrada: Echiniscidae) signalize a pseudocryptic horn of plenty

Gasiorek, Piotr, Oczkowski, Artur, Blagden, Brian, Kristensen, Reinhardt M., Bartels, Paul J., Nelson, Diane R., Suzuki, Atsushi C., Michalczyk, Łukasz 01 July 2021 (has links)
The cosmopolitan echiniscid genus Hypechiniscus contains exclusively rare species. In this contribution, by combining statistical morphometry and molecular phylogeny, we present qualitative and quantitative aspects of Hypechiniscus diversity, which remained hidden under the two purportedly cosmopolitan species: H. gladiator and H. exarmatus. A neotype is designated for H. gladiator from Creag Meagaidh (Scotland), and an informal re-description is provided for H. exarmatus based on animals from Creag Meagaidh and the Isle of Skye (Inner Hebrides). Subspecies/forms of H. gladiator are suppressed due to the high developmental variability of the cirrus dorsalis. At the same time, four species of the genus are described: H. daedalus sp. nov. from Roan Mountain and the Great Smoky Mountains (Southern Appalachian Mountains, USA), H. flavus sp. nov. and H. geminus sp. nov. from the Yatsugatake Mountains (Honshu, Japan), and H. cataractus sp. nov. from the Malay Archipelago (Borneo and the Moluccas). Dorsal and ventral sculpturing, together with morphometric traits, are shown to be the key characters that allow for the phenotypic discrimination of species within the genus. Furthermore, the morphology of Hypechiniscus is discussed and compared to that of the most similar genera, Pseudechiniscus and Stellariscus. Finally, a diagnostic key to all recognized Hypechiniscus species is provided.

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