Thesis (Ph.D.)--Oregon, Dept. of Biology Vita Bibliography: l. 177-184

Desde a revisão taxonômica dos Ophidiasteridae por H. L. Clark (1921), em que 20 gêneros foram reconhecidos como válidos, vários novos gêneros e espécies foram incluídos nesta família, e os limites entre alguns deles se tornaram largamente arbitrários. Isso também se aplica a Narcissia Gray, 1840, cuja morfologia e taxonomia são, ainda hoje, muito malcompreendidas. Os principais objetivos desta pesquisa foram: revisar a taxonomia do gênero Narcissia ao longo de toda a sua área de distribuição, a partir de estudos morfológicos; redescrever e caracterizar, morfologicamente, Narcissia trigonaria Sladen, 1889 strictu senso; caracterizar, morfologicamente, N. canariensis (d\'Orbigny, 1839) e N. ahearnae Pawson, 2007, as duas espécies válidas mais semelhantes a N. trigonaria; rever a validade de N. trigonaria helenaeMortensen, 1933; rever a validade de N. gracilis malpeloensis Downey, 1975. Cercade 370 espécimes do gênero Narcissia foram analisados: dois indivíduos de N. ahearnae, 82 espécimes de N. canariensis, 44 de N. gracilis e 242 de N. trigonaria. O material que serviu de base para nossos estudos pertence às coleções de museus nacionais e estrangeiras. Aterminologia para estruturas morfológicas seguiu Clark (1921), Turner & Dearborn (1972),Clark e Downey (1992) e Gale (2011). As pedicelárias foram classificadas de acordo com Jangoux e Lambert (1988). Todas as estruturas morfológicas de importância taxonômica foram ilustradas. E, pela primeira vez, os caracteres internos deste grupo foram estudados, a partir de microscopia eletrônica e tomografia. Uma nova diagnose para o gênero Narcissia foi disponibilizada. Todas as espécies do gênero foram revisadas e morfologicamente redescritas. Narcissia trigonaria, descrita a partir de um juvenil, foi redescrita a partir de um exemplar adulto, proveniente da localidade tipo (Bahia). Narcissia ahearnae é considerada uma espécie válida, e N. canariensis e N. trigonaria entidades distintas. Narcissia trigonaria helenae foi colocada na sinonímia de N. trigonaria, e N. gracilis malpeloensis entrou para a sinonímia de N. gracilis. A classificação de Narcissia, dentro da Família Ophidiasteridae, foi contestada, a partir de caracteres morfológicos. Os dados obtidos neste trabalho são, de longe, os mais completos já adquiridos para o gênero Narcissia e, futuramente, podem servir de base para os estudos morfológicos de outros grupos da Classe Asteroidea. / Since the taxonomic revision of the Ophidiasteridae by H. L. Clark (1921), in which 20 genera were recognized as valid, several new genera and species were included in this family, and the boundaries between some of them became largely arbitrary. This also applies to Narcissia Gray,1840, whose morphology and taxonomy are still very poorly understood today. The main goals of this research were: review the taxonomy of the genus Narcissia, throughout its range of distribution, from morphological studies; redescribe and characterize, morphologically, N. trigonaria Sladen, 1889 str. s; characterize, morphologically, N. canariensis (d\'Orbigny, 1839) and N. ahearnae Pawson, 2007, the two valid species most similar to N. trigonaria; review the validity of N. trigonaria var. helenaeMortensen, 1933; review the validity of the N. gracilismalpeloensis Downey, 1975. About 370 specimens of the genus Narcissia were analyzed: two individuals of N. ahearnae, 82 specimens of N. canariensis, 44 of N. gracilis, and 242 of N. trigonaria. The material that has served as a basis for our studies belongs to the national and foreign collections. The terminology for morphological structures has followed Clark (1921), Turner & Dearborn (1972), Clark & Downey (1992) and Gale (2011). Pedicellariae were classified according to Jangoux & Lambert (1988). All morphological structures of taxonomic importance have been illustrated. And, for the first time, the internal characters of this group were studied, from electron microscopy and tomography. A new diagnosis for the genus Narcissia was constructed. All species of the genus were reviewed and morphologically redescribed. Narcissia trigonaria, described from a juvenile, was redescribed from an adult specimen, from the type locality (Bahia). Narcissia ahearnae is considered a valid species, and N. canariensis and N. trigonaria distinct entities. Narcissia trigonaria helenaewas placed in the synonymy of N. trigonaria, and N. gracilis malpeloensis into the synonymy of N. gracilis.The classification of Narcissia, within the Family Ophidiasteridae, was contested, frommorphological characters. The data set obtained in this work are, by far, the most complete already acquired within the genus Narcissia and, in the future, may serve as the basis for the morphological studies of other groups of the Asteroidea Class.

The causes of increasing outbreaks of Acanthaster planci on the Great Barrier Reef have been a point of hot debate in recent years. It is unknown whether the increased success is due to nutrient runoff, salinity levels, or a decrease in predation, among other possibilities. In this paper I argue that the primary influence on outbreak status is sea surface temperature. From existing literature, I demonstrate that sea surface temperature in the Great Barrier Reef has increased by 0.4°C per year over the past three decades. I attempt to tie this increase with an increase in frequency of A. planci outbreaks on a selection of reefs throughout the Great Barrier Reef region. Due to the development of A. planci, specifically the fact that it takes them between 2 and 3 years to reach full maturity, I examined the potential relationship between an outbreak and the sea surface temperature 1 and 2 years before the event. Through my exploration of the data and my subsequent data analysis, it is clear that there are no statistically significant results when comparing the three classifications of outbreak (active, incipient, and recovering) and not outbreaking populations with temperature at each of the three time relationships. However, when I considered the three stages of outbreak to be “affected” and those not outbreaking to be “unaffected”, I found a statistically significant relationship. This finding has important implications when looking at the temperature changes that have been predicted for the Great Barrier Reef region due to global climate change. If the water temperature continues to increase, A. planci will more often be living within their optimal temperature range and will be more successful, continue to have major outbreaks that devastate the reef ecosystem, and eventually destroy it all together.