Crescimento de Aegla manuinflata (Decapoda, Anomura, Aeglidae) em ambiente natural

Abstract

ABSTRACT. Growth of Aegla manuinflata (Decapoda, Anomura, Aeglidae) in natural environment. The aim of this work was to evaluate the growth of Aegla manuinflata Bond-Buckup & Santos, 2009 in natural environment. Samplings were monthly performed, from April/2006 to May/2007, in a tributary of Ibicuí-Mirim River, which belongs to the Uruguay River basin, at São Pedro do Sul municipality, state of Rio Grande do Sul, Brazil. Traps and dip nets were used to collect the animals. The specimens were sexed and had their cephalothoracic length (CL) measured, using a digital caliper with 0.01 mm precision. The growth was evaluated using the von Bertalanffy model. The growth curves in length (mm), for the data obtained through the modal progression, are described by the equations: Ct = 28.00 [1 -e -0.0047(t+10.63) ] for males and Ct = 25.16 [1 -e -0.0051(t+17.65) ] for females. The maximum estimated age for males was three years and for females was two years and six months. -e -0,0047(t+10,63) ] e Ct = 25,16 [1 -e -0,0051(t+17,65) ], respectivamente. Os machos atingem tamanhos maiores que as fêmeas. A longevidade foi estimada em três anos para os machos e dois anos e meio para as fêmeas. PALAVRAS-CHAVE.Modelo de von Bertalanffy, estimativa de tempo de vida, recrutamento.

Allometric growth, sexual maturity and reproductive cycle of Aegla castro (Decapoda: Anomura: Aeglidae) from Itatinga, state of São Paulo, southeastern Brazil

“…Conversely, the time at which the size at onset of morphometric maturity is attained may vary among species. In accordance to the somatic growth pattern data compiled by Silva-Gonçalves et al (2009), Cohen et al (2011 and Trevisan and Santos (2011), complemented by results obtained by Chiquetto-Machado et al (2016), species found in lower latitude locations (<25º) tend to grow more slowly and, thus, are expected to take longer to attain morphometric maturity than those found in higher latitude regions.…”

Shape and size variations of Aegla uruguayana (Anomura, Aeglidae) under laboratory conditions: A geometric morphometric approach to the growth

“…Our growth study during the molt and intermolt periods differ from traditional methods both in controlled conditions and the natural environment (renzulli & collins, 2000;steVens, 2012;gonçAlVes et al, 2009;treVisAn & sAntos, 2011), which have allowed an integral identification of growth.…”

“…The majority of these studies used modal analysis rather than focusing on the individual growth of each organism (VAz-ferreirA et al, 1945;bAhAmonde & lóPez, 1961;lóPez, 1965;bueno et al, 2000;sWiech-Ayoub & mAsunAri, 2001;noro & bucKuP, 2003;boss et al, 2006;silVA-cAstiglioni et al, 2006;gonçAlVes et al, 2009;treVisAn & sAntos, 2011). While these studies can provide relative growth rates for portions of the population (by sex or maturity), they cannot provide size increments or the intermoult period for individuals (steVens, 2012).…”

Reproduction, growth and longevity of the endemic South American crabAegla marginata(Decapoda: Anomura: Aeglidae)

“…In terms of longevity, females tend to live slightly longer than males, except for A. manuinflata (Trevisan & Santos 2011). The values of CL ∞ , k, t 0 and longevity found for males and females of A. marginata are similar, probably because decapod crustaceans tend to have more eggs that are smaller (Vogt 2013).…”

“…However, in most species, males are slightly larger than females, except for A. platensis (Bueno & Bond-Buckup 2000), where females are larger than males. In A. platensis, Bueno and Bond-Buckup (2000) propose that growth difference occurs because few larger males were caught and in A. manuinflata, Trevisan and Santos (2011) related the difference in longevity to a higher female mortality rate during the incubation period.…”