Reproduction of the flatfish Achirus lineatus (Pleuronectiformes: Achiridae) in Paranaguá Bay, state of Paraná, a subtropical region of Brazil

Abstract

ABSTRACT. The present study characterizes the oogenesis and the ovarian maturation scale, and determines the reproductive period, type of spawning, recruitment period, and population variations in the reproductive process of the flatfish Achirus lineatus (Linnaeus, 1758). Specimens were sampled on a monthly basis in the shallow near shore area of the Paranaguá Bay, state of Paraná, Brazil, from March 2006 to February 2007. The specimens collected were measured for morphometric data (total length and total weight) and their gonads were exposed for macroscopic evaluation. The gonads were subsequently removed, weighed and processed for microscopic analyses. Six phases of the ovarian follicle development were defined, as well as five ovarian development stages. Growth patterns differed between the sexes: negative allometry for females and positive allometry for males. Based on the seasonal assessments of the distribution of individual GSI values, the distribution of stages of gonadal development, individual body size, sex ratio, the ratio of juveniles to adults, and histological examination of the ovaries, reproduction was found to occur in the spring (spawning in batches), and recruitment in the autumn. These results show that A. lineatus is an estuarine-resident species that uses the study area for reproduction and recruitment, providing an argument in favor of the need to conserve the estuarine environment in order to preserve stocks. KEY WORDS. Oogenesis; maturity scale; reproductive period; type of spawning; sex ratio.

Two record-sized Pacific Lined Soles Achirus mazatlanus (Pleuronectiformes: Achiridae), from the Eastern Pacific

“…Other species of Achirus are usually medium-sized; Achirus lineatus has a maximum total length of 230 mm (Oliveira & Fávaro, 2010) and Achirus klunzingeri a maximum total length of 300 mm (Krupp, 1995).…”

Reproductive biology of the flatfish Etropus crossotus (Pleuronectiformes: Paralichthyidae) in the Paranaguá Estuarine Complex, Paraná State, subtropical region of Brazil

“…During the months before the reproductive period, there is an accumulation of tissue necessary to endure the reproductive cycle (Abelha & Goulart, 2008). The allocation of energetic resources to the allometric growth was negative for females and positive for males (Oliveira & Fávaro, 2010).…”

“…Some species of Brazilian coastal flatfishes have added to the knowledge about reproductive biology (Chaves & Vendel, 1997;Dias et al, 2005;Oliveira & Fávaro, 2010), food ecology (Chaves & Serenato, 1998;Lunardon-Branco & Branco, 2003;Guedes et al, 2004;Guedes & Araujo, 2008) and population composition. Even so, little is known about the autoecological parameters of most of the species that occur in Brazil.…”

Estrutura da assembleia ictioplanctônica em dois estuários tropicais de Pernambuco (Brasil), sujeitos a diferentes condições hidrológicas

“…Larvas de espécies consideradas residentes em estuários, a exemplo de representantes de Engraulidae, Clupeidae, Gobiidae, Gerreidae e Achiridae, são geralmente as mais freqüentes e abundantes em relação àquelas que desovam no mar (Barletta-Bergan et al, 2002). Além disso, Engraulidae e Clupeidae apresentam desova contínua e elevada fecundidade (Bonecker et al, 2007;Oliveira & Fávaro, 2010), resultando em elevada densidade larval ao longo do ano.…”