Data/hora: 08/06/2024 16:34:48

Provedor de dados: 	103	
País: 	Brazil	
Título: 	Reproductive plasticity of Hypostomus affinis (Siluriformes: Loricariidae) as a mechanism to adapt to a reservoir with poor habitat complexity	
Autores: 	Duarte,Silvana; Araújo,Francisco Gerson; Bazzoli,Nilo.	
Data: 	2011-10-01	
Ano: 	2011	
Palavras-chave: 	Brazil; Fish reproduction; Reproductive biology; Reservoirs; Tactics.	
Resumo: 	In this work we describe the gonad morphology and spawning season of Hypostomus affinis (Steindachner, 1877) in a tropical reservoir based on 55 males and 125 females. Our aim was to assess eventual adaptations in reproductive tactics developed by this riverine species inhabiting an oligotrophic reservoir with low habitat complexity, few rocks and few other preferred consolidated substrata. We described the stages of cells of reproductive lineage, gonadal development and some reproductive traits which were compared with information in the available literature. Cells from the spermatogenic lineage were spermatogonia, spermatocytes, spermatids and spermatozoa, and cells from the oocytarian lineage were primary oocytes, previtelogenic oocytes, cortical vesicle oocytes and yolk globules or vitellogenic. Five stages were described for the males/females according to the distribution of oocytes and spermatogenic lineage cells: resting; initial maturation; advanced maturation; partially spent/spawned; totally spent/spawn. Females outnumbered males and reached larger size. Synchronic ovary development in two groups was found with diameter of mature oocytes ranging from 2 to 3.35 mm. Indication of early maturation, a longer reproductive period and the production of smaller eggs in small clutches seems to be features of the reservoir population not found in riverine systems. Such changes in tactics may indicate a shift to an opportunistic strategy, helping the population to withstand environmental constraints and to succeed in this oligotrophic and poorly structured reservoir.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000500005	
Editor: 	Sociedade Brasileira de Zoologia	
Relação: 	10.1590/S1984-46702011000500005	
Formato: 	text/html	
Fonte: 	Zoologia (Curitiba)  v.28 n.5 2011	
Fonte: 	info:eu-repo/semantics/openAccess