Black scabbardfish

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Black scabbardfish
Aphanopus carbo1.jpg

Black scabbardfish ( Aphanopus carbo )

Systematics
Perch relatives (Percomorphaceae)
Order : Scombriformes
Family : Hair tails (Trichiuridae)
Subfamily : Aphanopodinae
Genre : Aphanopus
Type : Black scabbardfish
Scientific name
Aphanopus carbo
Lowe , 1839

The black scabbard fish ( Aphanopus carbo ) from the hairtail family (Trichiuridae) looks similar to the snake mackerel from the closely related Gempylidae family - the most striking difference is that its caudal fin is fully developed, but almost tiny. This feature calls for a functional explanation (see below).

At the fish market in Funchal on Madeira , this species of Scombriformes had long been valued as a food fish until the British chaplain Richard Lowe brought it to the knowledge of science in 1839.

In the deep waters, the black scabbard fish is copper-colored. Only when caught does it get its familiar black color due to the rapid change in pressure. It is fished with rods with a line of 1500 m in length to which up to 50 auxiliary rods are attached. In their stomachs, in addition to small deep-sea fish, eels were found that were eaten on their spawning migration.

Appearance

This scabbard fish becomes a little over 1.5 m long; it is dark brown-silver with a purple sheen, but soon darkens on the market to the blackness in which it is known (as "espada") by gourmets. Its body is 11 to over 13 times longer than high, but very narrow, almost ribbon-shaped. The long, pointed head makes up about 16% of the total length. The large eyes “glow” in incident light, like a cat - a common phenomenon in animals that live in low-light environments. In front of the eyes there is only one nostril on each side, which is otherwise very rare in fish, but does not have to mean that the fish is microsmatic ( weak odor ). The fish has 97 to 100 vertebrae and a mouth with large fangs. When the mouth is closed, the maxillary is largely covered by suborbitalia. The mouth and gill cavities are pigmented black on the inside ( melanin - apparently so that bioluminescent light from digestive processes does not reveal the fish; see Coccorella !). Sideline developed normally; Scales are missing (the fish is therefore ripe for Jews ).

Fin formula : D XXXIV-XLI / 52-56, A II / 42-48, P 11-14. V has long been absent at sexual maturity, but is still present as a sting in larvae and young fish.

Scabbard fish on the cooling shelf

Occurrence

The scabbardfish live meso to bathy pelagic at a depth of 200 to 1700 m in the North Atlantic between Bermuda , Newfoundland , Labrador , Disko Island , Iceland , the Orkney Islands and Madeira as well as over several submarine mountains in between. It rises into the open water at night and sinks again in the morning. Another six very similar species, which have been delimited since Lowe, make the genus almost circumglobal. (Population studies see)

Behavior and meaning

Q. Bone has watched the scabbard fish acquire prey. It swims anguilliform (snaking like an eel - see  fins ); but as soon as he spots a prey, he goes over to ostraciiform swimming: the body becomes stiff, only the tail and the small caudal fin are moved and give the victim the impression that the approaching fish cannot be dangerous due to its apparently small size. Thus for instance Macrouriden , Moriden (moridae) and Alepocephaliden , but also Sepioidea (squid) and Peracariden overwhelmed.

Aphanopus reaches sexual maturity from a length of 80–85 cm. The maximum age is 12 years; Females predominate. The otherwise “solitary” fish spawns epipelagically in the warmer parts of the sea in winter. The eggs are scattered in the open water; the larvae feed on plankton and therefore live in transparent water layers. The fry then go over to the "predatory" way of life and begin their hunt and the like. a. on smaller fish.

The espadas or scabbardfishes are only fished specifically off Madeira and (locally) off Portugal and Spain (with traditional longlines ), but as they are also caught in the nets as bycatch , they are considered endangered.

Edible fish

Preparation with bananas

To this day, many tourists in Madeira know this fish as edible fish under the name Espada , the Portuguese word for "sword". The Latin name is derived from (Greek) ἀϕανής “invisible; unsafe ”, (here :) disappeared, lost, and πούς,“ foot ”, (here :) ventral fin, as well as (lat.) carbo “ coal ”.

The heavy metal pollution (including cadmium and lead) is so high that it is advisable to limit consumption.

literature

  • Arthur Holl, Werner Meinel: The olfactory organ of the deep-sea fish Aphanopus carbo (Percomorphi, Trichiuridae). In: Helgoland scientific marine studies. Vol. 18, No. 4, 1968, ISSN  0017-9957 , pp. 404-423, doi : 10.1007 / BF01611678 .
  • Hartmut Joppien: Comparative anatomical and functional analysis studies on the jaw and gill apparatus of the predatory bony fish Aphanopus and Merluccius. In: Zoological contributions. NF 16, 1970, ISSN  0044-5150 , pp. 264-385.
  • Izumi Nakamura, Nikolaj V. Parin: Snake mackerels and cutlassfishes of the world. An annotated and illustrated catalog of the Snake Mackerels, Snoeks, Escolars, Gemfishes, Sackfishes, Domine, Oilfish, Cutlassfishes, Scabbardfishes, Hairtails, and Frostfishes known to date (= FAO Species Catalog. Vol. 15 = FAO Fisheries Synopsis. No. 125 , Vol. 15). Food and Agriculture Organization of the United Nations, Rome 1993, ISBN 92-5-103124-X .

Web links

Commons : Black Scabbardfish  - Collection of images, videos and audio files

Single receipts

  1. Sergio Stefanni, Halvor Knutsen: Phylogeography and demographic history of the deep-sea fish Aphanopus carbo (Lowe, 1839) in the NE Atlantic: Vicariance followed by secondary contact or speciation? In: Molecular Phylogenetics and Evolution. Vol. 42, No. 1, 2007, ISSN  1055-7903 , pp. 38-46, doi : 10.1016 / j.ympev.2006.05.035 .
  2. Quentin Bone: On the Scabbard Fish Aphanopus Carbo. In: Journal of the Marine Biological Association of the United Kingdom. Vol. 51, No. 1, 1971, ISSN  0025-3154 , pp. 219-225, doi : 10.1017 / S0025315400006573 .
  3. José G. Pajuelo, José A. González, José I. Santana, José M. Lorenzo, Antonio García-Mederos, Víctor Tuset: Biological parameters of the bathyal fish black scabbardfish (Aphanopus carbo Lowe, 1839) off the Canary Islands, Central -east Atlantic. In: Fisheries Research. Vol. 92, No. 2/3, 2008, ISSN  0165-7836 , pp. 140-147, doi : 10.1016 / j.fishres.2007.12.022 .
  4. hence the unspecific name “frostfish”.
  5. Maria J. Bebianno, C. Santos, J. Canário, N. Gouveia, D. Sena-Carvalho, C. Vale: Hg and metallothionein-like proteins in the black scabbardfish Aphanopus carbo. In: Food and Chemical Toxicology. Vol. 45, No. 8, 2007, pp. 1443-1452, doi : 10.1016 / j.fct.2007.02.003 .