Bathylaco nigricans
| Bathylaco nigricans | ||||||||||||
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Bathylaco nigricans |
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| Scientific name | ||||||||||||
| Bathylaco nigricans | ||||||||||||
| Goode & Bean , 1896 |
Bathylaco nigricans is a deep sea fish that occurs circumglobal in all warmer oceans.
features
Bathylaco nigricans becomes a maximum of 34 cm long and is black to dark brown in color, with the head, whose length is 24.5 to 32.5% of the standard length, is sometimes even darker. The head is scaly, round in cross section and ends in a blunt snout. The well-developed eyes are located on the front half of the head above the upper jaw. Their diameter is 3.8 to 10% of the standard length, the ratio changes with growth. The horizontal diameter is slightly larger than the vertical. The anterior nostrils are round, the posterior curved. The gill cover bones are very thin and soft. Bathylaco nigricans has relatively large cycloid scales . The dorsal fin begins just behind the middle of the body, the anal fin under the back of the dorsal fin. In both fins, the first two rays are significantly shorter than the others. The pelvic fins sit under the front end of the dorsal fin, the small pectoral fins set deep, a little in front of an imaginary vertical line at the end of the gill cover. The sideline largely follows the side midlines of the body. The skeleton is only slightly ossified, which is typical for deep-sea fish. A swim bladder and light organs are missing.
- Fin formula : Dorsal : 0 / 17-22; Anal : 0 / 11-12; Pectorals : 6-11; Ventral : 6-9; Caudal : 10 + 9 main rays.
- Scale formula : SL 45–48; QR 11-12.
- Vertebra : 41-42.
- Branchiostegal rays : 9-10.
- Gill trap rays on the first gill arches 11–17.
- Pyloric tubes 6–12.
Way of life
Bathylaco nigricans lives close to the coast in the tropical and subtropical regions of all oceans, meso - and bathypelagically at depths of 450 to 4400 meters, mostly between 1750 and 2200 meters. Because of the well-developed eyes, the large gap in the mouth, the numerous pointed teeth and the small gill-trap rays, one can assume that Bathylaco nigricans is a fast swimming predatory fish. Bathylaco nigricans is probably oviparous , hermaphroditism was not found. The larvae are pelagic .
The black scabbard fish ( Aphanopus carbo ) is one of the predators of Bathylaco nigricans .
literature
- Jørgen G. Nielsen & Verner Larsen: Synopsis of the Bathylaconidae (Pisces, Isospondyli) with a new eastern Pacific species. Galathea rept. 9: 221-238, pls. 13-15. PDF
Web links
- Bathylaco nigricans on Fishbase.org (English)