Recruitment periods of Tagelus divisus (SPENGLER, 1794) (Bivalvia; Psammobiidae) in the Paranaguá estuarine complex – PR.

Abstract

Tagelus divisus (SPENGLER, 1794) is a Psamobiidae bivalve of commercial value that inhabits shallow waters, buried in a sandy or sandy-muddy substratum. The present study analyzed the spatio-temporal distribution in an intertidal environment and some aspects of the population dynamics (recruitment) of that species in the Bay of Paranaguá (PR), for which two study places were established: St. I close to the access bars and St. II, in the medium section of the system, in which systematic collections were made, between abril/96 and outubro/97. Larger abundance of individuals was observed (juvenile) (p <0,05) in the more intern section of the estuary (St. II), of waters with mean salinity of 26 and of larger anthropic infl uence and, in the two places, preferential distribution in the higher tide levels, close to the Spartina belt. Larger recruitment rates were evidenced in the autumn and in the spring, following a reproductive pattern observed for several species of bivalve in the area.

Biometric Relationships and Evaluation of the Density of Tagelus angulatus Gray, 1847 (Mollusca, Solecurtidae) on the West African Coasts in Three Villages of the Community Protected Area of Urok, Guinea-Bissau

“…The overall average density for the three localities is 16.63±14.22 ind./m². This result is close to that of [21] on Tagelus divisus in Brazil, which found an average of 19.1±16.1 ind./m2 in the median area of the estuarine complex of Paranaguá. However, the density values for Tagelus divisus found by [22] in Biscayne Bay, Florida are different from those found in this study.…”

Aspectos reprodutivos de mexilhões (Bivalvia, Mollusca) no complexo estuarino de Paranaguá, Paraná, Brasil

“…CRUZ e VILALOBOS (1993 descreve o início da maturação sexual de em animais com valores acima de 18 mm da maior dimensão (descrito como comprimento) em populações da M. guyanensis na Costa Rica. Esta mesma espécie possui início de maturação sexual com valores acima de 21 mm da maior dimensão (descrito como comprimento) no sudeste do Brasil (PERREIRA et al, 2003;2007 SPLENGER, 1794(CHRISTO et al, 2012; para Anomalocardia brasiliana GMELIN,1791(BOEHS et al, 2008FERREIRA-JR et al, 2015). Segundo BOEHS et al (2008) Uma menor repleção das gônadas (associada à desova) foi observada durante os meses com temperaturas mais elevadas do ano para ambas as espécies.…”