The gametogenic cycle and life history of Nicolea uspiana (Polychaeta: Terebellidae) on the south-east coast of Brazil

Autor(es)

Senna Garraffoni, Andre Rinaldo ^[1] ; Yokoyama, Leonardo Querobim ^[2] ; Zacagnini Amaral, Antonia Cecilia ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Biol, Dept Biol Anim, BR-13083970 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Oceanog, Dept Oceanog Biol, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Marine Biological Association of the United Kingdom; v. 94, n. 5, p. 925-933, AUG 2014.
• Citações Web of Science: 0

Resumo

The gametogenic cycle and life history of Nicolea uspiana (Nogueira, 2003) (Polychaeta: Terebellidae) was studied by taking monthly samples over a 13 month period. Each month, 10 females were sorted; 50 oocytes were removed from the coelom of each specimen, and the maximum diameter was determined. Additionally, 10 males were sorted and 100 gametes were randomly selected from each specimen to evaluate their shape and maturation stage. This species is gonochoric and exhibits slight external sexual dimorphism (in the shape of the nephridial papillae). The sex-ratio of N. uspiana was 2.4 male for each female. The initial gametic stages of both sexes are produced in special structures called nephromixia. Oogenesis is extra-ovarian, and the germ cells are clumped and surrounded by follicle cells. These cells are ovulated into the coelomic fluid, and yolk synthesis occurs in this cavity. The maximum diameter of oocytes measured, 225 mm, showed that these eggs fall into the size-range for lecithotrophy. Furthermore, N. uspiana is an iteroparous species, as the mature individuals can breed several times during their lifetime. Male gonads release germ cells early in development, and sperm maturation also occurs in the coelomic fluid. The male gametes consist of flattened plaques of germ cells attached on their anterior part by a cytophore assuming a rosette-like appearance. Following maturation of the male cells, the spermatids produce arrays of stiffly vibratile tails, assuming a morula shape. The reproductive patterns and life history of the terebellids are also discussed. (AU)

• Processo FAPESP: 05/59809-7 - Estudo comparativo da morfologia e ultraestrutura dos espermatozóides, reprodução e desenvolvimento de Paraeupolymnia uspiana e duas espécies de Streblosoma como base para o entendimento da evolução da história de vida em Terebellidae (Annelida: Polychaeta)
• Beneficiário: André Rinaldo Senna Garraffoni
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado