Bulimulus tenuissimus (d'Orbigny, 1835) is a land snail of parasitological importance with a poorly understood biology. The goal of this laboratory study was to determine development and reproductive patterns in B. tenuissimus. Recently hatched individuals in seven groups of 10 were maintained in the laboratory for two years. To test for self-fertilization, 73 additional individuals were isolated. After 180 days the isolated snails showed no signs of reproduction. Subsequently, 30 of these snails were paired to test fertility. We noted the date and time of egg-laying, the number of eggs produced, the number of egg-layings per individual, the incubation period and hatch success. This species shows indeterminate growth. Individuals that were maintained with others, as compared to isolated individuals, laid eggs sooner, laid more eggs and had a greater hatching success. This species can self-fertilize, however, with lower reproductive success. Bulimulus tenuissimus has a well-defined reproductive period that is apparently characteristic for this species.

RESUMO.O conhecimento dos aspectos biológicos e morfológicos dos moluscos terrestres é importante para o desenvolvimento de medidas de controle de pragas e de estratégias de conservação de espécies. O presente trabalho teve como objetivo caracterizar os padrões de biologia e conquiliomorfometria de Dysopeas muibum Marcus & Marcus, 1968 e verificar o efeito do isolamento sobre seu ciclo de vida e a morfometria da concha, em condições de laboratório. Foi realizado o acompanhamento do crescimento da concha, da liberação de filhotes e da mortalidade de 80 moluscos, dos quais 40 foram mantidos isolados e 40 agrupados (10 moluscos por grupo) em condições naturais de temperatura, umidade relativa e fotoperíodo, desde o nascimento até 180 dias de vida, quando então foram aferidas as medidas da concha. Os moluscos foram criados em terrários plásticos vedados com tecido de algodão e elástico, tendo como substrato terra vegetal esterilizada e alimentados com ração para frangos enriquecida com carbonato de cálcio. Foi verificado que os indivíduos possuem a concha pequena, alongada e são capazes de se reproduzir por autofecundação. Possuem crescimento indeterminado, iteroparidade, baixa mortalidade antes e após a maturidade sexual e a fecundidade aumenta de acordo com o tamanho corporal. O isolamento atuou na fecundidade, embora não tenha influenciado o crescimento, o alcance da maturidade sexual, a relação crescimento-reprodução, a mortalidade e a conquiliomorfometria. PALAVRAS-CHAVE.Reprodução, Gastropoda, morfometria, concha.ABSTRACT. Life cycle of Dysopeas muibum (Mollusca, Subulinidae) in laboratory: effect of isolation on biological and conquiliomorphometric patterns. The knowledge of biological and morphological characteristics of terrestrial molluscs is important for the development of pest control measures and strategies for the conservation of species. This study aimed to characterize the patterns of biology and conquiliomorphometrics of Dysopeas muibum Marcus & Marcus, 1968 and check the effect of isolation on its life cycle and morphometric of the shell, under laboratory conditions. We conducted monitoring growth of the shell, release of puppies and mortality of 80 molluscs, of which 40 were kept isolated and 40 grouped (10 molluscs per group) in natural conditions of temperature, relative humidity and photoperiod, from birth to 180 days of life, when the measures of the shell were taken. The molluscs were reared in plastic terrariums sealed with cotton fabric and elastic, containing plant soil sterile, and fed with food to broilers enriched with calcium carbonate. It was found that the species has small and elongated shell, and is able to reproduce by self-fertilization. It has indeterminate growth, iteroparity, low mortality before and after sexual maturity and fecundity increases with body size. The isolation acted on fertility, although it has not influenced the growth, reach sexual maturity, growthreproduction relation, mortality and conquiliomorfometrics.