Description of the newly-hatched juvenile of Aegla paulensis (Decapoda, Anomura, Aeglidae)

Abstract

The postembryonic development of Aegla paulensis is epimorphic (= direct), in which the hatching form is a juvenile that morphologically resembles the adult. Hatching is asynchronous, taking 3-5 days for all juveniles from a single brood to hatch. This paper provides a complete description of the external morphology of the newly-hatched juvenile of A. paulensis as analyzed through light microscopy (LM) and scanning electron microscopy (SEM). One of the striking features observed in the newly-hatched juvenile of A. paulensis was the presence of four pairs of rudimentary pleopods, a trait never described before in early juveniles of Aegla. Additional novelties include three unique types of setae and two types of pore sensilla.

Description of the newly-hatched juvenile of Aegla perobae (Crustacea: Decapoda: Aeglidae)

“…Ovigerous females carrying eggs in the final embryonic developmental stage [see Bueno & Shimizu (2008) for egg development categories] were sampled at the type-locality (22°31'26.6"S, 047°56'37.6" W) in July 2008 and in July 2010, and transported to and maintained alive at the University of São Paulo according to procedures and techniques described by Francisco et al (2007) and Moraes & Bueno (2013). Females were checked daily for newly-hatched juveniles in the brooding chamber.…”

“…Approximately 130 newly-hatched juveniles were obtained from eight ovigerous females and fixed by graded ethanol series (7.5%-15%-30%, 10 minutes each step) and stored in 50% ethanol solution. Carapace length (CL) was measured from the posterior border of the orbital sinus to the midposterior border of the cephalothorax; carapace width (CW) was measured as the largest transverse distance (Francisco et al 2007;Moraes & Bueno 2013).…”

“…The hatching form is an epibenthic juvenile that very much resembles the adult in general morphology (Francisco et al 2007;Moraes & Bueno 2013).…”

“…Seventy-five species of Aegla have been described so far, and complete descriptions and illustrations of newly-hatched juveniles are available for six species from Brazil only: Aegla prado Schmitt 1942, A. violacea BondBuckup & Buckup 1994, A. platensis Schmitt 1942, A. franca Schmitt 1942, A. schmitti Hobbs III 1979, and A. paulensis (Bond-Buckup et al 1996Bond-Buckup et al 1999;Francisco et al 2007;Teodósio & Masunari 2007;Moraes & Bueno 2013). Furthermore, morphological descriptions of newlyhatched juveniles of A. ligulata Bond- Buckup 1994 andA.…”

Revisão taxonômica e análise cladística de Aegla Leach, 1820 (Crustacea, Anomura, Aeglidae) com ocorrência nas bacias hidrográficas do Alto Paraná e do Alto Uruguai

“…Além disso, estudos morfológicos dos indivíduos imaturos também têm sido realizados, porém, descrições completas do jovem recém-eclodido estão disponíveis somente para sete espécies: Aegla prado Schmitt, 1942, A. violacea Bond-Buckup & Buckup, 1994, A. platensis Schmitt, 1942, A. franca Schmitt, 1942, A. schmitti Hobbs III, 1979, A. paulensis Schmitt, 1942e A. perobae Hebling & Rodrigues, 1977(BondBuckup et al, 1996Bueno & Bond-Buckup, 1996;Bond-Buckup et al, 1999;Francisco et al, 2007;Teodósio & Masunari, 2007;Moraes & Bueno, 2013;Moraes & Bueno, 2015). Além desses trabalhos, também existem descrições dos jovens de A.…”