The genus Ancilla Lamarck, 1799, contains 34 valid species and subspecies; 41 names previously applied to the group are reduced to 23, and 11 new species described (Kilburn, 1977, 1980, 1981). A provisional subgeneric classification is proposed. Subgenus Hesperancilla Kilburn, 1981, is established for the Brazilian A. matthewsi Burch & Burch, 1967, and Javancilla Kilburn, 1981, for the Eocene A. boettgeri Martin, 1914. Inadequate data on its type species prevents definition of subgenus. Ancilla s.s. at this stage, but Recent Indo-Pacific taxa are provisionally divided into (a) subgenus Sparellina P. Fischer, 1883, with an autapomorphic pectinate rachidian and (b) subgenera sparella Gray, 1857, and Chilotygma H. &. A. , Adams, 1853, with synplesiomorphic tricuspidate rachidians. The phylogeny and biogeography of the genus are discussed. The subfamily Ancillinae is reclassified, and a tentative cladogram proposed. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1981.

Submitted by Alberto Vieira (martins_vieira@ibest.com.br) on 2018-01-18T20:12:45Z No. of bitstreams: 1 543160.pdf: 5752993 bytes, checksum: fb44c0ac5d4e363215881e09350d98fc (MD5) / Made available in DSpace on 2018-01-18T20:12:45Z (GMT). No. of bitstreams: 1 543160.pdf: 5752993 bytes, checksum: fb44c0ac5d4e363215881e09350d98fc (MD5) Previous issue date: 2001 / CAPES / FAPERJ / Amostragens mensais foram realizadas entre junho/1998 e agosto/2000 na praia da Restinga da Marambaia, RJ com o intuito de estudar a biologia populacional e a produção secundária de Olivancillaria vesica vesica (Mollusca: Gastropoda: Olividae). Os animais foram coletados manualmente em dois transectos e tiveram o comprimento e a largura de suas conchas medidos em campo. O crescimento e a mortalidade foram estimados através de métodos computacionais baseados nos dados de frequência de comprimentos contidos no programa FISAT. A longevidade foi estimada pela equação invertida de von Bertalanffy considerando como tmax 95% do comprimento assintótico. Os métodos de Hynes e Crisp 3A foram utilizados para o cálculo da produção secundária. Picos populacionais foram observadas durante o inverno (setembro/1998 e 1999) e outono (junho/2000). Os parâmetros estimados indicam crescimento com moderada oscilação sazonal onde as menores taxas de crescimento ocorreram no final do verão (1º ano) e primavera (2° ano). A longevidade variou entre 4,28 e 4,99 anos. As estimativas de produção secundária variaram entre 0,142 e 0,213 g PSLC m-2 ano-1 . A proporção sexual foi de 1,18 para os machos. Foi observado a ocorrência do fenômeno de masculinização das fêmeas (Imposex) nessa espécie. / Monthly samples were carried out between June 1998 and August 2000 in Restinga da Marambaia beach, RJ with the purpose of study the population biology and secondary production of Olivancillaria vesica vesica (Mollusca: Gastropoda: Olividae). Specimens were handmade collected in two transects and the lenght and width of your shells were measured in the field. Growth and mortality was estimated using computer based methods of lenght-frequency data contained in FISAT package. Life span was estimated by inverse von Bertalanffy growth equation considering tmax as the 95% of the asymptotic lenght. Hynes and Crisp 3A methods were utilized for the calculation of secondary production. Highest population densities were observed during winter (September 1998 and 1999) and autumn (June 2000). Parameters estimated indicate moderated seasonal oscillations in growth with the slowest growth rates occuring in late summer (1st year) and spring (2nd year). Life span varied between 4.28 and 4.99 years. Secondary production estimatives varied between 0.142 and 0.213g AFDW m-2 year -1 . The sex ratio was 1.18 for males. Occurence of imposex in females of this species was observed.