Ahnelt and Keckeis, 1994



Citation


Ahnelt, H. and Keckeis, H. (1994) Breeding tubercles and spawning behavior in Chondrostoma nasus (Teleostei: Cyprinidae): a correlation?. Ichthyol. Explor. Freshwaters, pp. 321-330

Associated characteristics


Species Development state Trait Primary Data Secondary Data
Chondrostoma nasus Spawning conditions Mating system The spawning act, in which several males are involved, lasts only a few seconds. After releasing the eggs, the females swim a short distance upstream, then drift back with the current to their former position. This procedure is apparently repeated several times until all eggs are shed. No category
Chondrostoma nasus Spawning conditions Spawning substrate Over gravel Lithophils
Chondrostoma nasus Spawning conditions Spawning temperature When water reach 8-12°C 10.0 °C
Chondrostoma nasus Spawning conditions Spawning water type Sites with swift current Flowing or turbulent water
Chondrostoma nasus Spawning conditions Spawning depth Spawn in shallow water (20-50 cm) 35.0 m
Chondrostoma nasus Female Female sexual dimorphism Females in Fischa River. In smaller females (348 mm SL), the tubercles on the head run forward in a single row from about the dorsal margin of the anterior part of the operculum above the eye to the nasal opening. Larger specimens (370-409 mm SL) have larger breeding tubercles which additionally occur on the dorsal part of the operculum and on the dorsal part of the head. Females in Danube. Females exceeding 396 mm SL may also bear a few tubercles on the snout Present
Chondrostoma nasus Male Male sexual dimorphism Tubercles occur on the head, nearly the entire body, and on all fins. In males exceeding 350 mm SL, even the anterior side of the snout is covered Absent
Chondrostoma nasus Spawning conditions Spawning migration distance Migrate 4 km upstream to the spawning ground 4.0 km
Chondrostoma nasus Spawning conditions Spawning migration period Each year the specimens enter the river from the Danube in the mid-to late March. The spawning migration of the males starts two to three weeks earlier than the males ['March']
Chondrostoma nasus Spawning conditions Spawning season March-April ['April', 'March']
Chondrostoma nasus Female Length at sexual maturity 6 females sampled 348-406 SL in April in River Fischa. 6 females sampled 275-409 mm SL in April in River Danube 377.0 cm
Chondrostoma nasus Male Length at sexual maturity 6 Males sampled 289-397 SL in April in River Fischa. 8 males sampled 312-380 mm SL in April in River Danube 343.0 cm