Results 231 to 240 of about 3,600 (245)

Reproductive strategies and developmental aspects in mormyrid and gymnotiform fishes

Journal of Physiology-Paris, 2002
Comparative data on the reproduction in captivity and ontogenetic development of six of mormyrid species and seven gymnotiform species are reported. Mormyrid fishes: egg diameter ranged from 1.8 (Petroephalus soudanensis) to 3.0 mm (Hippopotamyrus pictus.
Frank, Kirschbaum, Christian, Schugardt
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A Study on Force Generated by Gymnotiform Undulating Fin

2018 15th International Conference on Ubiquitous Robots (UR), 2018
Underwater vehicles inspired by the motion of fish can generate a highly efficient force. This paper considers the gymnotiform undulating fin which imitates the motion of South American black ghost knifefish. The equations of the force generated by both continuous and discontinuous sine wave are established.
Van Hien Nguyen, Canh An Tien Pham, Van Dong Nguyen, Dae Hwan Kim, Tan Tien Nguyen   +4 more
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The South American Electric Fish Genus Platyurosternarchus (Gymnotiformes: Apteronotidae)

Copeia, 2009
Abstract The electric fish genus Platyurosternarchus, family Apteronotidae, is reviewed based on both external morphology and osteology. Synapomorphies for Platyurosternarchus are identified, the genus is diagnosed, and a key to the species is provided.
de Santana, Carlos David, Vari, Richard P.   +1 more
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Chromosomal characterization of two species of genus Steatogenys (Gymnotiformes: Rhamphichthyoidea: Steatogenini) from the Amazon basin: sex chromosomes and correlations with Gymnotiformes phylogeny

Reviews in Fish Biology and Fisheries, 2011
Gymnotiformes are an important component of the Neotropical ichthyofauna and they are known for their ability to generate and detect electrical discharges. Phylogenetic relationships of Gymnotiformes are still not well understood. However, the monophyly of the superfamily Rhamphichthyoidea is well accepted, despite the position of tribe Steatogenini ...
Cardoso, Adauto Lima, Pieczarka, Júlio César, Feldberg, Eliana, Milhomem, Susana Suely Rodrigues, Moreira-Almeida, Thiago, dos Santos Silva, Danillo, Silva, Patrícia Corrêa da, Nagamachi, Cleusa Yoshiko   +7 more
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Complex sex chromosome system in Eigenmannia sp. (Pisces, Gymnotiformes)

Genetica, 1984
Chromosomes of Eigenmannia sp. (7 males and 15 females) collected from the Tiete River in Botucatu (SP, Brazil) were examined from gill, kidney and testicular cells. The diploid chromosome number in males was 2n=31 and in females, 2n=32. In both sexes the number of chromosomal arms was 40.
Toledo, L. F. de Almeida, Foresti, H., Toledo Filho, S. de Almeida   +2 more
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Gymnotiform fish: an important component of Amazonian fioodplain fish communities

Journal of Fish Biology, 1996
Estimates of the density, biomass and species diversity of fish from floating meadow and flooded forest habitats suggest that gymnotiform fish constitute an important component of Amazonian flood plain fish faunas. Electric eels, Electrophorus electricus are unexpectedly abundant within Varzea forest.
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Study on Velocity Control of Gymnotiform Undulating Fin Module

2020
Inspired by the fish swimming motion of gymnotiform type, an undulating fin module has been developed in the effort to replace the traditional propulsion system of autonomous underwater vehicles. Base on the modelling of force generated in the undulating process of gymnotiform undulating fin module, the force has the non-linear relationship with ...
Van Hien Nguyen, Canh An Tien Pham, Van Dong Nguyen, Tan Tien Nguyen   +3 more
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Efferent projections of the posterior lateral line lobe in gymnotiform fish

Journal of Comparative Neurology, 1982
AbstractThe posterior lateral line lobe (PLLL) of gymnotoid fish has efferent projections to two midbrain regions: the nucleus praeeminentialis dorsalis (n.P.d.) and the torus semicircularis dorsalis (T.Sd.). Both ipsilateral and contralateral connections are present; the n.P.d. receives nearly equal input from both sides while the T.Sd.
L, Maler, E, Sas, C E, Carr, J, Matsubara   +3 more
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Spermatic cell characteristics in Gymnotiformes (Teleostei: Ostariophysi) and their phylogenetic meaning

Journal of Fish Biology, 2009
Spermatic characteristics were studied in representatives of the families Rhamphichthyidae, Sternopygidae and Apteronotidae, and compared with pre‐existent data from Gymnotidae and Hypopomidae. The spermatic characteristics found in Gymnotiformes were also compared with data from other Ostariophysi spermatic cells.
Franca, G. F., Oliveira, C., Quagio-Grassiotto, I.   +2 more
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Neurogenesis, cell death and regeneration in the adult gymnotiform brain

Journal of Experimental Biology, 1999
ABSTRACT Gymnotiform fish, like all teleosts examined thus far, are distinguished by their enormous potential for the production of new neurons in the adult brain. In Apteronotus leptorhynchus, on average 105 cells, corresponding to approximately 0.2 % of the total population of cells in the adult brain, are in S-phase within any period ...
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