The gonads of Aegla platensis Schmitt (Decapoda, Anomura, Aeglidae): a macroscopic and histological perspective

Abstract

 Abstract Sokolowicz, C.C., López-Greco, L.S., Gonçalves, R.S. and Bond-Buckup, G. 2007. The gonads of Aegla platensis Schmitt (Decapoda, Anomura, Aeglidae): a macroscopic and histological perspective. -Acta Zoologica (Stockholm) 88 : 71-79The aim of this study is to characterize the gonads of Aegla platensis , relating aspects of colour and size of ovaries, testes and vasa deferentia (VD) to histological observations. The ovaries are H-shaped, extending from behind the stomach and ending at the 1st or 2nd abdominal somite. The male has a pair of testes from which the VD issue and extend over the pereon. For males and females, macroscopic categories of gonad development are defined. Stages of the male gonad are defined as types 1, 2 and 3. Type 1 includes the less developed gonads, and type 3 includes extremely developed testes and completely differentiated VD. The ovaries are classified into four stages according to their colour: I (white), II ( yellow), III (orange) and IV (red), beginning with the least developed gonads. The number and size of oogonia and oocytes depend on the stage of the ovary and coincide with the different degrees of development as indicated by ovary colour. In males, the presence or absence of spermatozoa in the testes and VD is determined only for the more developed gonads. Neither spermathecae (female) nor spermatophores (male) were found. The lack of spermatophore in the present species is a rare characteristic among the anomurans.

Mating behavior of Aegla platensis (Crustacea, Anomura, Aeglidae) under laboratory conditions

“…According to Sokolowicz et al (2007), this is a mass of unbound spermatozoa produced along the vas deferens of males and transferred to females during copulation. However, the transfer of these spermatozoa was not directly observed.…”

“…In Brazil, it occurs in the southwest of Santa Catarina state, and in all of Rio Grande do Sul state, except for its northeastern region (Bond-Buckup 2003). This species is a good experimental model for field and laboratory studies, and several aspects of its natural history have already been studied, including growth pattern , population ecology , embryology (Lizardo-Daudt and Bond-Buckup 2003), physiology and diet (Bueno and Bond-Buckup 2004;Ferreira et al 2005;Oliveira et al 2007), and morphology (Sokolowicz et al 2006;Sokolowicz et al 2007). …”

“…This procedure was repeated daily. The criterion used for ovaria classification was modified from Sokolowicz et al (2007). According to this color criterion, females with white and orange ovaria were classified as immature, and those with red ovaria were classified as mature.…”

Maturidade sexual morfológica de Aegla platensis (Crustacea, Decapoda, Anomura) no Lajeado Bonito, norte do estado do Rio Grande do Sul, Brasil

“…Considerando-se que a análise da maturidade sexual está associada à biologia reprodutiva dos organismos, percebe-se que, embora alguns aspectos da reprodução dos eglídeos venham sendo estudados ultimamente (TUDGE & SCHELTINGA, 2002;SOKOLOWICZ et al, 2006;SOKOLOWICZ et al, 2007) armadilhas confeccionadas com garrafa pet contendo isca de fígado bovino como atrativo aos animais. As referidas armadilhas (n=16) foram colocadas antes do anoitecer, em locais propícios para a presença de eglídeos, como a presença de substrato para refúgio, e revisadas na manhã do dia seguinte.…”

Histological Validation of Morphochromatically-Defined Gonadal Maturation Stages of Green Abalone (Haliotis fulgens) Philippi,1845 and Pink Abalone (Haliotis corrugata) Wood, 1828

“…The color of the gonad changes as cells mature inside it, thus allowing the recognition of different stages based on macroscopic features. This sort of descriptions have been successfully used in fish species such as Clarias ngamensis Castelnau 1861 and C. gariepinus Burchell, 1822 (Mokae et al, 2013), in which macroscopic gonad characteristics have been used to recognize males; in crustaceans such as Parastacus defossus Faxon, 1898 (Noro et al, 2008) and Aegla platensis Schmitt, 1942(Sokolowicz et al, 2007, in which the gonad maturation process has been described in terms of changes in the histological characteristics and coloration of the gonad; and in other mollusks such as the giant squid Dosidicus gigas d 'Orbigny, 1835(Diáz-Uribe et al, 2006, in which cell morphometry has been used to differentiate between gonad maturation stages by comparison with external features, and gastropods such as Strombus gigas Linnaeus, 1758, in which various macroscopic and histological features have been described for different maturation stages (Aldana Aranda et al, 2003). Najmudeen & Victor even considered macroscopic features such as gonad color and percent coverage in the conical appendage, for the study of Haliotis varia Linnaeus, 1758.…”