Pristigaster cayana Cuvier, 1829
Amazon hatchet herring
photo by FAO

Family:  Pristigasteridae (Pristigasterids)
Max. size:  14.5 cm SL (male/unsexed)
Environment:  pelagic
Distribution:  South America: Amazon drainage (from perhaps mouth of Rio Branco at Goiaçu, Rio Solimões, Rio Juruá and as far as the Río Ucayali in Peru). (There are possibly two species, judging from specimens in the Museu de Zoológia, Sao Paulo).
Diagnosis:  Dorsal spines (total): 0-0; Anal spines: 0-0; Anal soft rays: 45-54. Belly profile strongly convex (almost circular from throat to anus), 30 to 33 scutes. Lower jaw projecting, mouth directed almost vertically upward; no toothed hypo-maxillary bone between hind end of pre-maxilla and lower bulge of maxilla blade; eye large. Pectoral fins high on body; anal fin origin behind dorsal fin base; upper caudal fin lobe ending in a filament in larger fishes (Ref. 188).
Biology:  Occurs in rivers but perhaps entering slightly saline waters near the mouth of Amazon (but this part of its range is not well documented). Compared with the `flying' characoid fishes (e.g. Thoracocharax), the vertically aligned scute arms in Pristigaster and the rather small pectoral muscles show that flight by vibration of the pectoral fins is almost certainly impossible. This species having been caught along with Thoracocharax raises the question of mimicry.
IUCN Red List Status: Least Concern (LC); Date assessed: 06 March 2017 Ref. (119314)
Threat to humans:  harmless
Country info:   

Entered by: Binohlan, Crispina B. - 17.10.90
Modified by: Bailly, Nicolas - 16.07.13
Checked by: Binohlan, Crispina B. - 27.07.94

Source and more info: 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 Not for publication.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 sortiz, 10/02/17