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Taxonomy, biogeography and ecology of Andean tardigrades at different spatial scalesRamsay, Balbina January 2018 (has links)
Micrometazoans are animals smaller than 2 mm. Their biogeography is poorly understood, and tardigrades provide a tractable phylum for exploring distribution patterns at a variety of scales. Polylepis forest habitat offers considerable advantages for making tardigrade comparisons across a wide range of scales in the Andes. This thesis aims to improve identifications of tardigrades with a character matrix approach, to assess the relative importance of habitat and bryophyte host on tardigrades, to describe the fine-scale spatial structure of tardigrade assemblages, and to estimate the sampling effort required for a reliable estimate of tardigrade diversity within Polylepis forest. Samples of bryophytes and lichens were collected from Polylepis forest and neighbouring habitats, and the tardigrades extracted and identified, mostly to operational taxonomic units. Some new species were discovered during the course of this work; one is described here. Abundance, diversity and composition of tardigrade samples were compared quantitatively. The thesis presents the first example of a character matrix for a tardigrade genus, bringing together information for the genus Isohypsibius from many different sources and describing suites of characters for each species. It will facilitate identification within the genus in future. Tardigrade assemblage data were highly variable within the samples, with empty samples dominating one study. Analysis of one forest site indicated that at least 50 samples would be needed to characterise the tardigrade diversity there. Although both were important, habitat-scale effects were more influential on tardigrade abundance, diversity and composition than host-scale effects. In both cases, microenvironmental and resource filters are the likely mechanisms driving these differences. Based on the results, recommendations are made for expanding such research into broader geographical scales: standardising sample volume, replicate sampling across hosts on the forest floor, recognising the importance of habitat-scale effects when selecting study sites, and the development of character matrices for tardigrade genera.
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Phylogeny and taxonomy of the complex thalloid liverwort family Cleveaceae caversRubasinghe, Sumudu Chandima Kumari January 2011 (has links)
Liverworts (Phylum Marchantiophyta) form the earliest diverging lineage of extant land plants and hold a key position in the evolutionary history of land plants. The family Cleveaceae, first defined in 1881 by Leitgeb by its complex thallus anatomy and star-shaped epidermal pores with strongly thickened radial walls, is now included within Marchantiopsida (Complex Thalloid Liverworts). The family is widely distributed in warm temperate to arctic regions throughout the Northern Hemisphere, but very rare in South America and absent from Australia and New Zealand. Since Cleveaceae was described, the number and names of genera and species recognized within the family have changed many times, with three genera currently accepted: Athalamia (12 to 15 species), Sauteria (2 to 5 species) and Peltolepis (1 or 2 species). However, no robust phylogenetic frame work or taxonomic monographs of the family have previously been undertaken and the species diversity within the genera remains uncertain. The study presents the first robust phylogenetic framework for the family, based on three chloroplast genes (psbA, rpoC1 and rps4) and one nuclear ribosomal region (26S) sequenced for 54 ingroup accessions representing a substantial part of the geographic range of the family (except South America) and a large part of its morphological diversity. Samples sequenced include the type species of the three currently accepted genera as well as those of previously synonymised genera; Clevea, Spathysia, Gollaniella and Sauchia. The current circumscription and relationships of the genera were tested using Maximum Parsimony, Bayesian and Likelihood inferences. Cleveaceae was strongly supported as monophyletic with four main lineages resolved within the family, two corresponding to Peltolepis and Sauteria and two composing a polyphyletic Athalamia. The latter is therefore divided into a more narrowly defined Athalamia and a fourth genus, for which Clevea is the earliest published name. Inferred evolutions of twelve morphological characters, that are useful or have been used in classifications of Cleveaceae, were reconstructed using maximum parsimony and maximum likelihood methods. The misleading influence of homoplasy on past morphological classifications and phylogenies is discussed. The study also presents the first worldwide taxonomic revision of Cleveaceae based on around 2300 specimens studied, including all available type specimens. The monographic work is based on morphological and anatomical characters reviewed using dissecting, compound and scanning electron microscopes including both herbarium and fresh material collected on field excursions during the study. Ventral scale morphology, position and aggregation of androecia and shape of receptacle were found to be valuable characters in generic and species delimitation. The traditional definition of genera of Cleveaceae based mainly on two characters (carpocephalum stalk position and anatomy) was rejected. A total of seven species were recognized from 25 formerly described names including one new necessary combination: Clevea hyalina (Sommerf.) Lindb., C. spathysii (Lindenb.) Müll. Frib., C. pusilla (Steph.) Rubasinghe & D.G.Long comb. nov., Athalamia pinguis Falc., Sauteria alpina (Nees) Nees, S. spongiosa (Kashyap) S.Hatt., and Peltolepis quadrata (Saut.) Müll. Frib. Nine excluded and doubtful species are listed along with reasons for their exclusion. Generic and species keys are presented based on vegetative, reproductive and spore morphological characters. For each genus and species, descriptions, illustrations, and distribution maps are given along with ecological, taxonomic and nomenclatural notes.
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Taxonomic studies in CyperaceaeOteng-Yeboah, Alfred Apau January 1972 (has links)
Part I deals with the supra-specific classification of the subfamily Cyperoideae (excluding the tribe Rhynchosporeae) on a world-wide basis. It involves a broad survey of comparative exomorphic and endomorphic characters, with an analysis and synthesis of all available information from the literature. Many microscopic features of the leaf, culm, glume; hypogynous perianth bristle, stamen, style, stigma and fruit have been examined, many of them for the first time. Most of these features, together with the already known characters commonly used in the classification of genera in the subfamily Cyperoideae, have been employed to form the basis of the supra-specific classification presented here. The two large Linnaean genera, viz: Scirpus and Cyperus, have been split into a number of small, natural genera. Four distinct taxa, previously included in Scirpus a.l., are for the first time accorded generic status, though formal generic names have not been given to 3 of these. These 3 unnamed genera have been temporarily called Genera A, B and C. Cyperus, in the restricted sense used here, is found still to be partly unnatural, but further studies are needed before attempting to change its circumscription. Of the 47 genera adopted in this work, 25 are monotypic and/or geographically restricted; the rest being widely distributed. The maximum concentration of species and genera is found to occur in the tropics. Formal taxonomic treatments have been given to all the 47 genera in the conclusion, except for those genera which were not personally investigated; for the latter only keys for their identification and appropriate literature references have been given. An informal tribal and subtribal grouping has been proposed to accommodate the narrower, more natural genera adopted, since the limits of the traditional tribes Cypereae and Scirpeae no longer stand. New nomenclatural combinations, as well as the list of species and citation of voucher specimens studied anatomically, have been given in Appendices. Part II deals with the revision of the entire subfamily Cyperoideae as it is represented in the area covered by the Flora of Turkey (Davis 1965-). 47 species representing 21 genera are found in this area. This number includes taxa either seen by me or accepted from reliable records in the literature. Descriptions, synonymy, habitats, specimen citations on a grid basis, notes on the variability of Turkish species, and a key for their identification have been included in this account. Two new taxa have been discovered, for which English diagnoses have been given. Finally, an attempt has been made to explain some of the apparent disjunctions in the distribution of certain species in Turkey.
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BIODIVERSITY OF THE PARASITE FAUNA OF THE RODENT GENERA ZYZOMYS THOMAS, 1909 AND PSEUDOMYS GRAY, 1832 FROM NORTHERN AUSTRALIA.Weaver, Haylee Jade, haylee.weaver@anu.edu.au January 2008 (has links)
This study of the parasite fauna of five Australian rodents (Muridae:
Hydromyinae: Conilurini) was undertaken to increase the knowledge of
Australian parasite biodiversity.
Trapping for Zyzomys argurus (Thomas, 1889), Pseudomys delicatulus (Gould,
1842), P. desertor Troughton, 1932, P. gracilicaudatus (Gould, 1845) and P.
hermannsburgensis (Waite, 1896) (Rodentia: Muridae) was carried out at 16
locations in Queensland between 2004 to 2006. A total of 51 rats were captured
and examined for parasites. In addition, 119 rats, from collections in the
Queensland Museum and the University of Sydney, were examined. Finally, 57
samples of parasites collected from the above hosts and deposited at the
Australian National Wildlife Collection (CSIRO) were identified.
From these five rodent species, 15 species of ectoparasites and 17 species of
endoparasites were recorded. Fifteen new host records and 14 new locality
records were found. The ectoparasites comprised four species of Laelaps Koch,
1836 (Parasitiformes: Laelapidae), four species of chiggers (Acariformes:
Trombiculidae), two species of fleas (Siphonaptera: Pulicidae, Pygiospyllidae)
and two species of ticks (Parasitiformes: Ixodidae). Three new species of lice
(Anoplura: Hoplopleuridae) were discovered.
The 17 endoparasites, all helminths, comprised fourteen species of nematode and
three species of cestode. There were 11 species of oxyurids (Nematoda:
Oxyuridae, Heteroxynematidae), including 10 new species of Syphacia, two
species of Odilia (Nematoda: Heligmonellidae), and one species of
Nippostrongylus (Nematoda: Heligmonellidae). Three species of cestodes
(Cestoda: Anoplocephalidae, Taeniidae, Davaineidae) were collected. There
were no trematodes or acanthocephalans found in any of the rodents examined.
No protistan parasites were found in tissue and blood samples taken from the
rodents.
The mean species diversity of parasites for each host rodent species was
consistently low, with values of Simpsons Reciprocal Index ranging from 1.00
1.53. Possible factors contributing to this low diversity include habitat
preferences, dietary ecology and social structure. There was no significant
relationship found between host body weight and abundance of ectoparasites, or
host body weight and species richness of helminths. The index of discrepancy
(D) was used to evaluate the distribution of parasite species across host
populations. Most parasites were found to have aggregated distributions within
the host populations. The exception to this was two of the four species of laelapid
mite, with values <5, indicating that they were common across host populations.
The phylogenetic relationships of the Syphacia species occurring in the
Australian bioregion were investigated using morphological characters.
Relatively low resolution of the trees produced indicated that there may be a high
degree of similarity between species. Two main clades were identified- a clade of
genera of Syphaciini from Borneo was shown to be basal to the clade of species
of Syphacia examined. Within the clade of the genus Syphacia, the new species
identified in this study formed a single cluster on trees. There was no evidence,
however, for strict coevolution of these worms and their hosts.
Overall, the research presented here adds considerable knowledge to the previous
paucity of information of the parasites of Australian native rodent species. This
was achieved by contributing new host records, locality records and identifying
and describing several new species. The relationships between conilurin rodents
and their parasites suggests that coevolution plays a large part in the speciation of
parasites, and that minimal host switching has occurred in the helminths of the
conilurins of northern Australia.
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Taxonomic study of Myrmarachne (Araneae: Salticidae) from TaiwanHuang, Jiun-Nan 07 September 2004 (has links)
Based on the taxonomic system of Platnick in 2004, a total of 11 species of Myrmarachne are recognized from Taiwan. There are 4 species described as new species: M. exilisata sp. nov., M. lanyuensis sp. nov., M. luteopalpis sp. nov., and M. laticorseleta sp. nov., and 3 new records to Taiwan: M. annamita Zabka., 1985, M. edwardsi Berry, Beatty and Proszynski, 1996 and M. kiboschensis Lessert, 1925. And the species published in the past from Taiwan are recovered and redescribed in this study, namely, Myrmarachne formosana (Saito, 1933), Myrmarachne formosicola Strand, 1910 and Myrmarachne inermichelis Bösenberg and Strand, 1906 and Myrmarachne magna (Saito, 1933), and female of Myrmarachne formosana (Saito, 1933) and Myrmarachne formosicola Strand, 1910 are described and illustrated first time. Type specimen of M. formosicola Strand, 1910 was re-examined. We treat Pyroderes formosanus Matsumura, 1911 as a doubtful species. A taxonomic key of Myrmarachne from Taiwan, diagnoses, descriptions, quantitative character values, illustrations, locality records, and distribution maps are presented for the 11 recognized species.
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Handling Unexpected Workflow Exceptions: A Case-Based Reasoning ApproachLiang, Ching-Jing 19 July 2000 (has links)
Workflow management is more and more popular and its technologies are becoming more and more mature. However, an important feature that is essential to many business process are left unsolved ¡V namely the unexpected exception handling. Not only does unexpected exceptions degrade the performance of WFMS, it also reflects the defects of workflow design. Our research proposes a framework that uses case-based reasoning to find exception handling rules from historical exception instances. These exception handling rules can help both improving exception handling performance and enabling workflow evolution.
Our framework includes an exception taxonomy, an exception case base, and a set of exception naïve models. When an exception occurs, it is classified into a particular category according to the exception taxonomy. Within the category a number of attributes are compared and a naïve model that best represents the incoming exception is identified. It is then adapt to the current environment for an appropriate handling approach. We discuss in the thesis how to discover naïve models from a set of exception instances. A case is finally studied to demonstrate the feasibility of our framework and address the issues of some subtle considerations.
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A Study on Leaf Morphology of Melastomataceae in TaiwanHsiao, Ping-min 30 July 2008 (has links)
ABSTRACT
A comparative morphological study on the leaf of Melastomataceae was made for 21 species of 11 genera in Taiwan. The morphological characters studied include leaf venation, trichome, epidermal cell, anticlinal wall, stomatal type and crystal type. The results are given as follows. Two types of venation are recognized, i.e. pinnate and palmate venations. The leaves of all species showed their palmate venation except for those of Memecylon lanceolatum. Seven types of trichrome could be observed in the studied species, which consist of peltate scales, bladder-like glandular hairs, multiseriate unbranched hairs, multiseriate unbranched glandular hairs, short-stalked glandular hairs, armed hairs and stellate with glandular hairs. All of species have short-stalked glandular hairs occurred on the leaves of all species except Memecylon lanceolatum which has no trichrome at all. In addition, bladder-like glandular hairs on upper epidermis of leaves in Medillia and on both epidermis of leaves in Blastus. The epidermal cells of the leaf surfaces are polygonal or irregular in shapes, and the anticlinal walls are straight, arched, repand and sinuous. There are five types of stomata, which are composed of anomocytic type, diacytic type, paracytic type, polocytic type and staurocytic type. Only Melastoma kudoi and Osbeckia chinensis have stomata at upper epidermis. Two kinds of crytals appeared, i. e. styloids and druses. However, the occurrence of crystal is unstable specifically and generically, which implies that it is invaluable for specific and generic delineation. Additionally, druses could be found epiphytic on multiseriate unbranched hairs of the genera Melastoma and Osbeckia. According to this study, the features of leaf venation, trichrome, epidermis cell, anticlinal wall and stomatal type could provide evidence for taxonomy of this family.
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Morphological And Pathogenic Analyses Of Varieties Of Waitea Circinata And Their Rhizoctonia Anamorphsde la Cerda, Karla Adriana 19 September 2011 (has links)
The species complex, Waitea circinata (WC) has been currently divided into five cultural types: var. circinata, var. oryzae, var. zeae, var. agrostis, and var. prodigus. These divisions are currently based on differences in their sclerotial morphology which have been supported by differences in their internal transcribed spacer region. Physiological differences such as optimal growth temperature, and morphological and pathogenic analyses as well as molecular biological techniques, were used to examine a broad WC collection coming from different geographic regions, and different susceptible hosts. The pathogenic examination showed that WC varieties are not host specific and can successfully infect both turfgrasses and cereals. Phylogenetic trees based on Neighbor-joining (NJ) and Maximum likelihood (ML) methods for three genomic regions (ITS, beta-tubulin, IGS1) showed support for only three of the five WC cultural types that have been described, namely Waitea circinata var. circinata, var. oryzae and var. zeae." / Waitea circinata varieties were characterized using molecular, morphological, physiological and pathological techniques. / Ontario Turfgrass Research Foundation, CONACYT (Ministry of Science from Mexico)
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Systematics of the Archiborborinae (Diptera: Sphaeroceridae)Kits, Joel 29 September 2011 (has links)
The Archiborborinae comprise a diverse clade of flies in the family Sphaeroceridae. This thesis presents the first phylogenetic analysis and a thorough taxonomic revision of the subfamily. The phylogenetic revision includes morphological data from all species, and molecular data from a subset of 21 ingroup species. Although the group here treated as the Archiborborinae has been traditionally treated as a tribe within the subfamily Copromyzinae, analysis of morphological, molecular, and combined datasets supports the monophyly of the Archiborborinae and shows that the Archiborborinae and Copromyzinae are not sister taxa. The Copromyzinae are more closely related to the Sphaerocerinae and possibly to the enigmatic genus Pycnopota than they are to the Archiborborinae. The elevation of the clade to subfamily rank is supported on the basis of this evidence. Basal relationships within the Archiborborinae are difficult to resolve, but the phylogenetic evidence generally supports a division of the subfamily into the following 8 genera: Antrops Enderlein 1909, Penola Richards 1941, Frutillaria Richards 1961, Boreantrops gen. nov., Coloantrops gen. nov., Maculantrops gen. nov., Photantrops gen. nov., and Poecilantrops gen. nov. The genus Archiborborus, until recently a paraphyletic assemblage including most of the described species in the subfamily, is treated as a junior synonym of Antrops (syn. nov.) All genera are described and a generic key is provided. A total of 122 species, including 25 previously described and 89 new, are fully described and illustrated; another 8 new species are diagnosed but not formally named.
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Life history and population dynamics of the crangonid shrimps Crangon crangon and Philocheras trispinsus on Port Erin Bay, Isle of ManOh, Chul-Woong January 1999 (has links)
No description available.
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