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Systematics of the Onychoteuthidae Gray, 1847 (Cephalopoda: Oegopsida)Bolstad, Kathrin S. Unknown Date (has links)
Squids in the family Onychoteuthidae Gray, 1847 have been reported from every ocean but the Arctic, are taken frequently in deep-sea fisheries by catch, and are ecologically important in the diets of many marine predators including cetaceans, pinnipeds, sharks, and seabirds. However, the diversity and systematic of the family have remained poorly understood. Of the 60+ nominal species, 12–14 have generally been accepted in recent studies. Challenges to clarity include insufficient species descriptions, original descriptions published in eight languages and often based solely on early life stages, non-designation or subsequent loss of type material, and the existence of several unresolved species complexes. In light of the general systematic disarray of the Onychoteuthidae, a global revision of the family follows, based on ~1500 specimens examined from 19 repositories. Type material has been examined wherever possible; for some species, photographs of type specimens, original illustrations, and/or the original descriptions have provided the only information available. It has not been possible to fully disambiguate taxa in some cases (e.g. Gen. nov. 2), given the limited material and information available, but for all species treated in this revision (25 out of 26 species; no material was available for Kondakovia nigmatullini), descriptions and illustrations are provided to a consistent standard that will enable their reidentification. External and internal morphological characters and states are described for sub adult to adult stages of most species, with external characters reported through ontogeny as permitted by available material. Historically important characters are treated (general external morphology, body proportions, tentacle clubs, photophores, gladius, lower beak, radula), augmented by several more recently recognised characters (palatine teeth, detailed morphology of the tentacular hooks in adults, tentacular suckers in paralarvae, chromatophore patterns). The systematic value of both historical and new morphological characters at the generic and species levels are discussed; at all ontogenetic stages, tentacular club and hook morphology are considered the most valuable characters, although body proportions and gladius also prove useful. Partial disambiguation of the Onychoteuthis banksii complex has been possible in the Pacific and Atlantic Oceans, resulting in the resurrection of Onychoteuthis bergii Lichtenstein, 1818 and Onychoteuthis aequimanus Gabb, 1868, the description of two new species, Onychoteuthis lacrima and Onychoteuthis prolata (in press), and the expansion of one species’ recognised distribution (Onychoteuthis compacta) to include the Atlantic Ocean. The genus Moroteuthis Verrill, 1881 is considered a junior synonym of Onykia Lesueur, 1821, in accordance with the findings of several earlier authors. However, morphological differences in the species ‘Moroteuthis’ ingens necessitate the resurrection of the subgenus Moroteuthopsis Pfeffer, 1908b, with all other Onykia species placed into a new subgenus, Onykia (Onykia). Sexual dimorphism is reported in the beaks of Onykia (Moroteuthopsis) ingens (new comb.), and revised sex-specific equations are given for estimating this species’ biomass based on LRL. Morphological and historical genetic data suggest a more distant relationship between Onykia and the species ‘Moroteuthis’ knipovitchi Filippova, 1972 than was suggested by earlier classifications. This species is therefore considered to represent an undescribed genus, herein referred to as Gen. Nov. 1, which cannot be more fully diagnosed and described at present due to limited material. The generic position of ‘Onykia’ rancureli (Okutani, 1981) is also uncertain; it may be allied to Walvisteuthis virilis Nesis & Nikitina, 1986 (family Walvisteuthidae Nesis & Nikitina, 1986), but confirmation is impossible without examining type material of W. virilis. A second new genus, Gen. Nov. 2, is therefore described for ‘Onykia’ rancureli and several morphological variants reported from the Pacific and Atlantic Oceans. Given that the majority of available onychoteuthid material was collected after 1950, resulting in the descriptions of over half of the generally accepted genera and species since 1960, ongoing collection programmes are necessary to further resolve onychoteuthid systematic.
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Exploring evolutionary patterns and processes : a case study using the Mesozoic bivalve BuchiaGrey, Melissa 05 1900 (has links)
The fossil record is the only direct source of data for studying modes (patterns) and rates of morphological change over geologic time periods. Determining modes is critical for understanding macroevolutionary processes, but just how modes can vary within a taxon, and why, have hitherto been largely understudied. To address this, I examined patterns of morphological change in the shell of the Mesozoic marine bivalve genus Buchia over its geographic and temporal range. Buchia was chosen as a test subject because it is abundant, well-preserved across a variety of facies,
and is widely distributed across the Northern Hemisphere where the likelihood of
multiple lineages is low. While the focus of this thesis is on evolutionary patterns, it
is also necessary to address issues of taxonomy and geographical variation, making
this research applicable to a wide-variety of fields.
Previous to this study there was no protocol for measuring buchiid valves, nor was
the genus studied in a quantitative manner. Throughout this research I used ten
morphological characters to describe shell shape and size. Multivariate methods
(principle component and canonical variate analyses) were employed to discriminate
between species of Buchia and examine how morphological characters change through time and space within the genus. Evolutionary patterns were delineated using two well-established programs that discriminate between multiple modes of evolution. Overall, nearly 2000 specimens from eight geographical locations around the world were studied for this thesis.
I found the genus Buchia was a useful tool for evolutionary studies as it can be
studied quantitatively in space and time. Specically I have found that buchiid species can be delineated using morphometrics; the genus is restricted to the Northern Hemisphere; while the environment significantly affects morphology, there is no
evidence of a latitudinal gradient; diversity and disparity within Buchia are not correlated; most evolutionary modes conformed to random walks or stasis; and modes and rates vary across the geographical range of the genus. Overall, I have found that the environment plays an important role in shaping both morphology and modes.
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Taxonomy and epidemiology of the genus arcobacterCollado González, Luis Roberto 29 January 2010 (has links)
El género Arcobacter incluye especies capaces de producir patología gastrointestinal en humanos y aborto, diarrea y mastitis en ganado. Sin embargo se desconoce su prevalencia en el agua y no existen métodos que permitan la identificación de sus 9 especies. En esta tesis hemos desarrollado un protocolo (16S rDNA-RFLP) capaz de diferenciar la mayoría de las especies. Además, demostramos que la presencia de Arcobacter en aguas se correlaciona con la contaminación fecal y que tiene una elevada prevalencia y diversidad genética en el río Llobregat. Sin embargo, estos microorganismos nunca fueron detectadas en al agua potable, lo que demuestra que el tratamiento de potabilización del agua del río es efectivo para su eliminación. Comprobamos que Arcobacter presentan una elevada prevalencia tanto en diferentes tipos de carnes como en mariscos. Finalmente, se han descubierto y descrito 4 especies nuevas para el género: Arcobacter mytili, Arcobacter valdiviensis, Arcobacter defluvii y Arcobacter molluscorum. / The genus Arcobacter includes species associated with human and animal diseases. However, its prevalence in water is unknown and so far do not exist methods able to differentiate the nine accepted species. In this thesis we have developed a molecular identification method (16S rDNA-RFLP) that enables the differentiation of most of species. In addition, we have demonstrated that the presence of Arcobacter in environmental waters correlates with high level of faecal pollution. Theses microorganisms showed a high prevalence in the Llobregat River and a high genetic diversity. However, these microorganisms were never detected from drinking water, which demonstrate that the treatment of the river water is effective for its elimination. Additionally, have been demonstrated the high prevalence of Arcobacter in several types of meat and shellfish. Finally, 4 new species have been discovered and described: Arcobacter mytili, Arcobacter valdiviensis, Arcobacter defluvii y Arcobacter molluscorum.
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A Taxonomic and Distributional Study of Seagrass in TaiwanKo, Chih-jen 06 September 2004 (has links)
Ten species of seagrasses are recognized in Taiwan and adjacent islands. They are, namely, Halophila beccarii Aschers., Halophila decipiens Ostenf., Halophila ovalis (R. Br.) Hook. f., Thalassia hemprichii (Solms) Aschers., Cymodocea rotundata Ehrenb. & Hempr. ex Aschers., Cymodocea serrulata (R. Br.) Aschers. & Magnus, Syringodium isoetifolium (Aschers.) Dandy, Halodule pinifolia (Miki) den Hartog, Halodule uninervis (Forssk.) Aschers. and Nanozostera japonica (Ascherson & Graebner) Toml. & Posl. The detail morphological charactors of these speices are descripted for the first time, and can be the basis of further research. These species are mainly distributed in the west coast of Taiwan, Hengchun peninsula, the Green Island, the Orchid Island, Hsiaoliuchiu, the Pescadores Islands, Quemoy and the Pratas Island, the habitats can be categorized as 4 types, which are muddy to sandy tidal flat, coral platform, wave-cut platform and fine-muddy seabed. The relation between types of habitat and occurrence is also discussed.
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A Taxonomic Study of Liparis L. C. Rich. (Orchidaceae) of TaiwanYang, Chih-Kai 31 July 2006 (has links)
The genus Liparis in Taiwan was taxonomically revised based on morphological,
phytogeographical and ecological evidences. Pseudobulb articulation, leaf number, lip and column are the most valuable characters for the classification within the genus in Taiwan. The morphology of leaf epidermis and seed coat also provide useful information in subgenus or section level. Geographically, eleven species are distributed in Machilus-Castanopsis zone, in which the species L. somai Hayata, L. campylostalix Rchb. f., L. wrayi Hook. f., and L. henryi Rolfe have strict distributional range. According to cladistic analysis, the result reveals that Liparis is a paraphyletic group rather than a monophyletic group. As a result of above studies, twenty-two taxa, including one variety and two uncertain species, are recongnized. L. japonica (Miq.) Maxim. and L. cespitosa (Thouars) Lindl. are synonyms of L. elongata Fukuy. and L. laurisilvatica Fukuy., respectively. L. kawakamii Hayata and L. derchiensis Ying are instead conspecific to L. nakaharai Hayata. and L. japonica (Miq.) Maxim. L. amabilis Fukuy. and L. hensoaensis Kudo. are treated as uncertain species due to insufficiency of evidence.
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A taxonomic student on Dioscorea L. (Dioscoreacea) of Taiwan.Liao, Chun-Kuei 12 June 2000 (has links)
Abstract
This thesis is to study habit, tuber, stem, leaf, flower and fruit morphology, phytogeography, and phenology in Dioscorea. Finally, concerns are given to the infrgeneric taxonomy.
Plants of Dioscorea in Taiwan are scandent vine; underground tuber or rhizome cylindrical, pyriform or spherical; steme terete or quadrangular in cross-section, ridged, or winged, green or violet, pubscent or glabrous or prickly; aerial tuber axilly or absent. Leaves alternate or opposite, simple or palmately- compound; simple leaves cordate or ovate-triangular, 3-9 nerved; leaflets of palmately-compound leaves lanceolate or ovate, nerves pinnately; 3-9 nerved; veinlets reticulate; petioles twisted and dilated at base. Flowers usually dioecious, arranged in axillay panicles, racemes, or spikes; male flowers solitary or fasciled on rachis, perianths 6, 2-whorled, tepals mostly similar, stamens 6, sometimes the inner 3 sterile, filaments attached to base of perianths, anthers 2 celled, longitudinally dehiscent, pistillodium rudimentary, present or absent; pistillate flowers solitary on rachis, perianths similar to the staminate, with 0, 3 or 6 staminodia; ovary inferior, trigonous, 3-celled, ovules 2 in each cell; stigmas 3, 2-lobed at apex. Fruit capsulate, tripterous. Seed 2 in each cell, with membranous wing. Flowering period is from April to September. Mostly fruiting from July to November. Most species of the genus in Taiwan are widely spreading in the island. Among the species in Taiwan, two endemic.
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Revision on Scolopendromorpha (Chilopoda) from TaiwanChao, Jui-Lung 02 September 2002 (has links)
Between 1991 and 2002 three hundred and sixteen specimens of scolopendromorphs were collected from 100 sites in Taiwan. In total, 16 species (subspecies) of 5 genera, Scolopendra, Rhysida, Otostigmus, Cryptops, Scolopocryptops (formerly Otocryptops) were found. Three species are new by record to Taiwan, i.e., Scolopocryptops capillipedatus (Takakuwa, 1938), Scolopocryptops melanostomus melanostomus Newport, 1845 and Cryptops japonicus Takakuwa, 1934. A revisionary status, Scolopendra multidens Newport, 1844, formerly regarded as a subspecies of Scolopendra subspinipes by Kraepelin in 1903, is now a valid species, distinguished by the presence of genital appendages in males, margined tergites, and the presence of a tarsal spine on 20th leg. A new status, Scolopendra subspinipes japonica L. Koch 1878 maybe a subspecies or a geographic variation of Scolopendra multidens Newport, 1844, because they only differ in the color of head capsule and sternital paramedian sutures. But it must be demonstrated further. In the case of Scolopendra subspinipes mutilans, it may be a young S. subspinipes subspinipes, because they only differ in the color of head capsule and body size. Five previously recorded species and 2 subspecies were, however, not found on the island during this study. Based on body measurements, it is proposed that Rhysida longipes brevicornis Takakuwa, 1932 = Rhysida longipes longipes (Newport, 1845), Rhysida nuda brevicornuta Wang, 1951 = Rhysida immarginata immarginata (Porat, 1876), and Otostigmus insularis Hasse, 1887 = Otostigmus malayanus Chamberlin, 1914 = Otostigmus scaber Porat, 1876. We did not find any specimens resembling the description of Otostigmus multispinosus Takakuwa, 1937. It could have been misidentified, as the presence of a very similar species Otostigmus aculeatus Haase, 1887 on the island.
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A Taxonomic Study of Athyrium in TaiwanLiu, Yea-chen 18 August 2008 (has links)
The genus Athyrium composed by 220 species in the world, mainly distributed in the Asia temperate regions. According to the observations of the morphological characters, this study revised the taxonomy and recognized 24 species and 2 varieties in Taiwan. The infrageneric scheme also due to morphology, these Taiwanese species were placed into 5 sections: Sect. Polystichoides, Sect. Echinoathyrium, Sect. Strigoathyrium, Sect. Atkinsonii and Sect. Niponica.
Basing on the public DNA sequences data (trnL-F and rbcL), including to this study providing, the molecular phylogeny analysis was state in this study. The Maximum Parsimony and Bayesian inference were used in each fragment: trnL-F region length 846 bp, 72 OTUs in 41 species 8 varieties; rbcL 1188 bp, 70 OTUs in 42 species 6 varieties, and combined data: 42 OTUs in 38 species 4 varieties. The phylograms contributed by each datasets are support the infrageneric scheme provided in this study, 5 sections occuring in Taiwan and 2 other sections (Sect. Athyrium and Sect. Yokoscentia) are monophyletic.
Herein, the key to the species of the Taiwanese Athyrium, science names, descriptions, voucher specimens and notes of each taxa are provided.
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Biosystematics of the Phacelia ranunculacea complex (Hydrophyllaceae)Sewell, Matthew. January 2003 (has links)
Thesis (M.S.)--Miami University, Dept. of Botany, 2003. / Title from first page of PDF document. Document formatted into pages; contains v, 53 p. : ill. Includes bibliographical references (p. 24-26).
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Exploring evolutionary patterns and processes : a case study using the Mesozoic bivalve BuchiaGrey, Melissa 05 1900 (has links)
The fossil record is the only direct source of data for studying modes (patterns) and rates of morphological change over geologic time periods. Determining modes is critical for understanding macroevolutionary processes, but just how modes can vary within a taxon, and why, have hitherto been largely understudied. To address this, I examined patterns of morphological change in the shell of the Mesozoic marine bivalve genus Buchia over its geographic and temporal range. Buchia was chosen as a test subject because it is abundant, well-preserved across a variety of facies,
and is widely distributed across the Northern Hemisphere where the likelihood of
multiple lineages is low. While the focus of this thesis is on evolutionary patterns, it
is also necessary to address issues of taxonomy and geographical variation, making
this research applicable to a wide-variety of fields.
Previous to this study there was no protocol for measuring buchiid valves, nor was
the genus studied in a quantitative manner. Throughout this research I used ten
morphological characters to describe shell shape and size. Multivariate methods
(principle component and canonical variate analyses) were employed to discriminate
between species of Buchia and examine how morphological characters change through time and space within the genus. Evolutionary patterns were delineated using two well-established programs that discriminate between multiple modes of evolution. Overall, nearly 2000 specimens from eight geographical locations around the world were studied for this thesis.
I found the genus Buchia was a useful tool for evolutionary studies as it can be
studied quantitatively in space and time. Specically I have found that buchiid species can be delineated using morphometrics; the genus is restricted to the Northern Hemisphere; while the environment significantly affects morphology, there is no
evidence of a latitudinal gradient; diversity and disparity within Buchia are not correlated; most evolutionary modes conformed to random walks or stasis; and modes and rates vary across the geographical range of the genus. Overall, I have found that the environment plays an important role in shaping both morphology and modes.
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