>
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
البيئة
; المياه العذبة قاعية التغذية و المعيشة. Tropical
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)
الحجم / وزن / العمر
Maturity: Lm ? range ? - ? cm
Max length : 18.0 cm SL ذكر/ مختلط الجنس; (Ref. 87956)
وصف مختصر
مفاتيح التعريف | الوصف الخارجي | قياسات المظهر الخارجي
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).
Life cycle and mating behavior
Maturities | التكاثر | Spawnings | Egg(s) | Fecundities | Larvae
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)
استخدامات بشرية
أدوات
تقارير خاصة
Download XML
مصادر علي الأنترنت
Estimates based on models
Phylogenetic diversity index (Ref.
82804): PD
50 = 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).
مستوى غذائي (Ref.
69278): 3.2 ±0.4 se; based on size and trophs of closest relatives
Fishing Vulnerability (Ref.
59153): Low vulnerability (12 of 100).
