Gymnotus varzea Crampton, Thorsen & Albert, 2005
No Picture Available

 Family:  Gymnotidae (Naked-back knifefishes)
 Max. size:  28.5 cm TL (male/unsexed); max.weight: 65.0 g
 Environment:  benthopelagic
 Distribution:  South America: Amazon basin in Brazil and Peru.
 Diagnosis:  Dorsal spines (total): 0-0; Dorsal soft rays (total): 0-0; Anal soft rays: 230-310. Distinguished from its congeners endemic to the Amazon and Orinoco Basins and the Guyana Shield in having a color pattern of 16-22 oblique dark pigment bands with wavy and irregular margins in which the majority of bands at midbody form X-shaped patterns (resembling metaphase chromosomes) and in which the dark bands are about twice as broad as the pale interbands. Further differs from its congeners in having the following unique combination of characters: clear (unpigmented) patch at the caudal end of the anal-fin membrane in specimens 6.0-23.7 cm; and bands never divided to form band pairs (Ref. 55508).
 Biology:  Found in root mats of floating meadows in floodplains (Ref. 55508). Gulps atmospheric air into the hypervascularized posterior chamber of its gas bladder (Ref. 55508). Feeds on small aquatic invertebrates such as chironomid larvae, insect nymphs and microcrustaceans (Ref. 55508).
 IUCN Red List Status: Not Evaluated  (Ref. 96402)
 Threat to humans:  harmless
 Country info:   
 

 Entered by: Torres, Armi G. - 27.09.05

Source and more info: www.fishbase.org. For personal, classroom, and other internal use only. Not for publication.


Page created by Jen, 05.08.02, php script by kbanasihan 06/09/2010 ,  last modified by dsantos, 20/08/10