You can sponsor this page

Gymnorhamphichthys britskii Carvalho, Ramos & Albert, 2011

Drop Knifefish
Upload your photos and videos
Google image
Image of Gymnorhamphichthys britskii (Drop Knifefish)
No image available for this species;
drawing shows typical species in Rhamphichthyidae.

Classification / Names Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa

Teleostei (teleosts) > Gymnotiformes (Knifefishes) > Rhamphichthyidae (Sand knifefishes)
Etymology: Gymnorhamphichthys: Greek, gymnos = naked + Greek. Rhamphos = beak, bill + Greek, ichthys = fish (Ref. 45335).

Environment: milieu / climate zone / depth range / distribution range Ecology

Freshwater; benthopelagic. Tropical

Distribution Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri

South America: Paraguay. Gymnorhamphichthys britskii is known from tributaries of the Rio de La Plata system. It is known from the upper and lower Paraguay (Neris et al., 2010) basins in Paraguay and Brazil, and the lower Parana´ basin in Paraguay, Brazil, and Argentina (no records from Uruguay basin). The presence of this species in the Upper Parana was likely caused by the formation of the Itaipu reservoir, which allowed dispersal into upstream portions of the Parana through the former Sete Quedas waterfalls (Ref. 87956)

Size / Weight / Age

Maturity: Lm ?  range ? - ? cm
Max length : 18.0 cm SL male/unsexed; (Ref. 87956)

Short description Identification keys | Morphology | Morphometrics

This species is distinguished from its congeners except G. hypostomus in having 5-16 (usually 9-13) large dark saddle-shaped pigment bars over the dorsal midline, extending between the nape and a vertical with the end of the anal fin, and sometimes reaching to or slightly below the lateral line; differs from G. hypostomus in having 141-172 (vs. 178-211) anal-fin rays; a shorter snout, preorbital distance 48.1-60.3% of head length (mean 54.6%) (vs. 58.3-68.6%, mean 63.9%); a larger eye, with diameter 5.7-9.0% of head length (mean 7.0%) (vs. 3.3-5.9%, mean 4.3%); a longer distance from tip of snout to posterior nares, 17.1-22.0% of head length (mean19.2%) (vs. 11.2-17.1%, mean 13.8%); 7 (vs. 9-13) displaced hemal spines; and 64-69 (vs. 71-75) vertebrae to end of anal fin (Ref. 87956).

Biology     Glossary (e.g. epibenthic)

Life cycle and mating behavior Maturities | Reproduction | Spawnings | Egg(s) | Fecundities | Larvae

Main reference Upload your references | References | Coordinator : Campos-da-Paz, Ricardo | Collaborators

Carvalho, T.P., Ramos, C.S. and J.S. Albert, 2011. A new species of Gymnorhamphichthys (Gymnotiformes: Rhamphichthyidae) from the Paraná-Paraguay Basin. Copeia 2011(3):400-406. (Ref. 87956)

IUCN Red List Status (Ref. 130435)

  Least Concern (LC) ; Date assessed: 18 November 2020

CITES

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

  Harmless





Human uses

FAO - Publication: search | FishSource |

More information

Trophic ecology
Food items
Diet compositions
Food consumptions
Food rations
Predators
Ecology
Ecology
Population dynamics
Growths
Max. ages / sizes
Length-weight rel.
Length-length rel.
Length-frequencies
Mass conversions
Recruitments
Abundances
Life cycle
Reproduction
Maturities
Fecundities
Spawnings
Spawning aggregations
Egg(s)
Egg developments
Larvae
Larval dynamics
Distribution
Countries
FAO areas
Ecosystems
Occurrences
Introductions
BRUVS - Videos
Anatomy
Gill areas
Brains
Otoliths
Physiology
Body compositions
Nutrients
Oxygen consumptions
Swimming type
Swimming speeds
Visual pigment(s)
Fish sounds
Diseases / Parasites
Toxicities (LC50s)
Genetics
Genetics
Electrophoreses
Heritabilities
Human related
Aquaculture systems
Aquaculture profiles
Strains
Ciguatera cases
Stamps, coins, misc.
Outreach
Collaborators
Taxonomy
Common names
Synonyms
Morphology
Morphometrics
Pictures
References
References

Tools

Special reports

Download XML

Internet sources

AFORO (otoliths) | Aquatic Commons | BHL | Cloffa | BOLDSystems | Websites from users | Check FishWatcher | CISTI | Catalog of Fishes: genus, species | DiscoverLife | ECOTOX | FAO - Publication: search | Faunafri | Fishipedia | Fishtrace | GenBank: genome, nucleotide | GloBI | Google Books | Google Scholar | Google | IGFA World Record | MitoFish | Otolith Atlas of Taiwan Fishes | PubMed | Reef Life Survey | Socotra Atlas | Tree of Life | Wikipedia: Go, Search | World Records Freshwater Fishing | Zoobank | Zoological Record

Estimates based on models

Phylogenetic diversity index (Ref. 82804):  PD50 = 0.5156   [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01000 (0.00244 - 0.04107), b=3.04 (2.81 - 3.27), in cm total length, based on all LWR estimates for this body shape (Ref. 93245).
Trophic level (Ref. 69278):  3.2   ±0.4 se; based on size and trophs of closest relatives
Fishing Vulnerability (Ref. 59153):  Low vulnerability (12 of 100).