Data/hora: 11/06/2024 14:45:48

Provedor de dados: | 83
País: | Brazil
Título: | Phenotypic plasticity associated to environmental hypoxia in the neotropical serrasalmid Piaractus mesopotamicus (Holmberg, 1887) (Characiformes: Serrasalmidae)
Autores: | Fernández-Osuna,María Alejandra; Scarabotti,Pablo Augusto.
Data: | 2016-01-01
Ano: | 2016
Palavras-chave: | Aquatic surface respiration; Characiformes; Dermal lip protuberances; Reaction norm; River floodplains.
Resumo: | ABSTRACT Many South American characid fishes develop reversible dermal protuberances in the jaws to optimize aquatic surface respiration (ASR) during hypoxia. To date, basic aspects of this adaptation remain unknown, mainly due to the scarcity of experimental studies. In laboratory experiments, we determined time necessary for the complete formation and reversion of these structures in Piaractus mesopotamicus , and studied comparatively behavioral, morphological, and respiratory responses along gradients of dissolved oxygen (DO) concentration. Morphological changes during hypoxia consisted in dermal protuberances of lower lip, anterior border of maxillary and distal border of opercular valve, increasing the known number of structures modified. These structures developed completely in less than 6 hours and reversed in less than 3 hours. Most of observed traits showed a logistic response curve with threshold DO values between 0.90 and 2.70 mgL-1. Respiratory frequency and opercular valve development showed similar threshold values above the level of tolerance of DO, whereas ASR and dermal protuberances of the jaws showed threshold values below this level. This observation supports the functional link between these groups of behavioral and morphological traits. This study demonstrates that this species is able to modify reversibly portions of the respiratory system to optimize responses to hypoxia.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000200210
Editor: | Sociedade Brasileira de Ictiologia
Relação: | 10.1590/1982-0224-20150187
Formato: | text/html
Fonte: | Neotropical Ichthyology  v.14 n.2 2016
Fonte: | info:eu-repo/semantics/openAccess