Feeding of Eigenmannia trilineata (Pisces, Sternopygidae) (Lopez & Castello, 1966), in the upper Paraná River floodplain, Brazil

Abstract

Studies were performed on various aspects related to the feeding of Eigenmannia trilineata in the upper Paraná River floodplain, from June 1993 to July 1994, at four places with different types of bottom and waters speed. A number of 279 fish had its stomachal contents analyzed by occurence and point methods in which it was applied on its frequencies the feeding index. Two hundred an sixty two specimens were utilized to the analysis of the feeding activity that it was based on frequency and middle degree of stomach repletion. For the morfological analyse utilized 12 individuals. It was verified fourteen items on species diet which it was found chiefly Chironomidae (Diptera) and detritus. Seasonal, area variations were verified in feeding activity and the participation of constituent items in diet. The results showed that the species presents nightly and benthophagous habits, with morfological characters of the carnivorous species.<br>Os estudos foram realizados sob vários aspectos relacionados à alimentação de Eigenmannia trilineata na planície de inundação do alto rio Paraná, de junho de 1993 a julho de 1994 em quatro locais com diferentes tipos de fundo e velocidade de águas. Um número de 279 peixes tiveram seus estômagos analisados pelos métodos de ocorrência e pontos sendo aplicado sobre suas frequências o índice alimentar. Duzentos e sessenta e dois indivíduos foram utilizados para a análise da atividade alimentar, a qual foi baseada sobre a freqüência e grau de repleção médio dos estômagos. Para a análise morfológica foram utilizados 12 indivíduos. Foi verificado 14 itens na dieta da espécie, encontrando-se principalmente Chironomidae (Diptera) e detritos. Variações sazonais e de área foram verificados na atividade alimentar e na participação dos itens constituintes da dieta. Os resultados mostraram que a espécie apresenta hábitos noturno e bentófago, com características morfológicas de espécies carnívoras

Análise do uso de microhabitat, distribuição espacial e dieta de Gymnorhamphichthys rondoni (Miranda-Ribeiro, 1920) (Rhamphichthyidae) em riachos de baixa ordem, Amazônia Ocidental

“…However, other food items besides benthic larvae were found in the diet of G. rondoni individuals, such as allochthonous items such as insect fragments, Hymenopterans, and other items such as arachnids and crustaceans. Similar results were found for other species of Gymnotiformes (PERETTI; ANDRIAN, 1999;GIORA et al, 2012;FERRIZ;IWASZKIW, 2014), which consumed prey of various nektobenthic and allochthonous origins. Also, remains of plants and algae were consumed at lower abundance and frequency.…”

“…Prey-speciic abundance was calculated with the equation %PAi = ∑n j=1 %Aij ni -1, where %Aij is the abundance (per number %PNi or volume %PVi) of prey i in stomach sample j and ni is the number of stomachs containing prey i. -PSIRI% is a modiication of the index of relative importance (IRI) (PINKAS et al, 1971).…”

Resource use by two electric fishes (Gymnotiformes) of the National Forest Saracá-Taquera, Oriximiná, Pará

“…Consumption of benthic prey was reported for several species of gymnotiforms (Winemiller, Adite, 1997;Peretti, Andrian, 1999;Giora et al, 2005;Luz-Agostinho et al, 2006;Rocha et al, 2009;Giora et al, 2012;Tesk et al, 2014), suggesting it is a pattern for this fish order (Giora et al, 2014). However, benthic prey was not the only food category consumed by G. rondoni and G. coropinae: both species consumed prey associated with macrophytes (e.g.…”

New species of glass knifefish genus Eigenmannia (Gymnotiformes: Sternopygidae) with comments on the morphology and function of the enlarged cephalic lateral‐line canals of Sternopygidae

“…Gasteropelecids, on the contrary, live just under the surface of the water and keep the top of head on the surface line – in this case is the widened supraorbital canal that is possibly being used to capture vibration caused by insects or other potential food particles that disturb the water surface. Available information on Eigenmannia behaviour show that this taxon is a bottom feeder that is most active during night‐time (Fortune et al ., 2019; Peretti & Andrian, 1999). It is a benthophagous invertivore taxon, with a diet composed of insect larvae, crustaceans and occasional autochthonous insects (Bichuette & Trajano, 2017; Giora et al ., 2005; Peretti & Andrian, 1999).…”

“…Available information on Eigenmannia behaviour show that this taxon is a bottom feeder that is most active during night‐time (Fortune et al ., 2019; Peretti & Andrian, 1999). It is a benthophagous invertivore taxon, with a diet composed of insect larvae, crustaceans and occasional autochthonous insects (Bichuette & Trajano, 2017; Giora et al ., 2005; Peretti & Andrian, 1999). Like the other taxa that have enlarged LL canals, it is possible that Eigenmannia uses its canals to detect food in its environment.…”