On the species of Gymnorhamphichthys Ellis, 1912, translucent sand‐dwelling Gymnotid fishes from South America (Pisces, Cypriniformes, Gymnotoidei)

@article{Nijssen1976OnTS,
  title={On the species of Gymnorhamphichthys Ellis, 1912, translucent sand‐dwelling Gymnotid fishes from South America (Pisces, Cypriniformes, Gymnotoidei)},
  author={H. M. C. Nijssen and Isa{\"a}c J. H. Isbr{\"u}cker and Jacques G{\'e}ry},
  journal={Studies on Neotropical Fauna and Environment},
  year={1976},
  volume={11},
  pages={37-63}
}
Summary Gymnorhamphichthys hypostomus and Gymnorhamphichthys rondoni are species with considerable variation in the length of the snout and in the position of the anal pore. A total of three hundred and thirty specimens were examined, including the holotype and 9 paratypes of Gymnorhamphichthys hypostomus Ellis, 1912, the single holotype of Urumara rondoni A. de Miranda Ribeiro, 1920, and the holotype and 20 paratypes of Gymnorhamphichthys hypostomus petiti Gery & Vu, 1964. A total of 205… 
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References

SHOWING 1-3 OF 3 REFERENCES
Food of Central Amazonian fishes. Contribution to the nutrient-ecology of Amazonian rain-forest-streams
The material studied was collected in the Brazilian Arnazon region some years ago. In 19ô5 Dr. E.-J. Fr.rß,ru of Plön, at the behest of sioli, caught the fishes. The primary aim of ór. Fittkau's