Flabellina affinis

from Wikipedia, the free encyclopedia
Flabellina affinis
Flabellina affinis

Flabellina affinis

Systematics
Superordinate : Heterobranchia
Order : Hind gill snails (Opisthobranchia)
Subordination : Nudibranchia (Nudibranchia)
Family : Flabellinidae
Genre : Flabellina
Type : Flabellina affinis
Scientific name
Flabellina affinis
( Gmelin , 1791)

Flabellina affinis , on German as Violette Fadenschnecke (although there are other types are called by that name) is a designated occurring in the Mediterranean marine slug of Nudibranchia .

Side view of Flabellina affinis
View from above

features

The body of Flabellina affinis is light purple in color. The tips of the cerata (dorsal threads) are also purple, but mostly darker in color than the body. Especially in the two lower thirds, the branches of the midgut gland shimmer orange-red. The Cerata are piston-shaped dorsal appendages, which contain the extensions of the midgut glands and are arranged symmetrically. In addition, respiratory function is ascribed to these processes. They are arranged in two longitudinal rows of eight groups each. The two feelers at the top of the head ( rhinophores ) have a ribbed surface, in contrast to the smooth Cerata. The rhinophores are about the same length as the mouth tentacles. Together with other characteristics, they serve as a distinguishing feature from the other Flabellina species. The rhinophores are primarily used for chemotaxis and flow sensitivity. The jaws consist of a short and strong purchase cortex, with a number of closely spaced and pointed cone-shaped teeth. The base of the Kaufortsatz has at least 5 rows of teeth.

distribution

The species is native to the entire Mediterranean . The distribution in the east Atlantic is from Spain over Portugal to Ghana , including the Canary Islands .

Reproduction and occurrence

The hermaphrodite snail can reproduce all year round and wraps its clutch around tree-like hydrozoic colonies of the genus Eudendrium . It is also found on these most frequently. The spawning lines are pink or light purple violet. The color of the eggs ranges from light pink, light purple to purple purple. The size of the eggs is 0.08 mm to 0.09 mm. The eggs are laid from March to October. At a water temperature of 20 ° Celsius, free-swimming Veligers hatch after 5 days. If the water temperature is around 16 ° Celsius, this happens after 8 days. They occur in water depths of over 50 m, most often in 20–30 m depth. Individuals of this species can grow up to 5 cm.

Kleptocnids

Nettle cells are only formed by representatives of the cnidarians ( Cnidaria ) tribe . Flabellina affinis feeds on hydroid colonies, possibly exclusively on Eudendrium species. Flabellina affinis only eats polyp heads . The nettle capsules of the prey are absorbed intact through the intestines and stored in the threads on the back and used to defend against predators.

Possible confusion

The purple coryphella ( Flabellina pedata ) is very similar to the Flabellina affinis in terms of size, shape and color. The main distinguishing feature is the white ends of the dorsal threads and their smooth rhinophores.

Aquaristics

The species is unsuitable for keeping in an aquarium due to the special housing requirements, particularly when it comes to food. There are also no animals offered in the trade or specifically bred.

literature

  • Louise Schmekel & Adolf Portmann: Opisthobranchia of the Mediterranean: Nudibranchia and Sacoglossa (Fauna e flora del Golfo di Napoli, 40). 410 S., Berlin, Springer Verlag 1982. Flabellina affinis : pp. 189-191 ( Google Books ). ISBN 3-540-11354-1
  • Bergbauer Humberg: What lives in the Mediterranean ?, Franckh-Kosmos Verlags-GmbH & Co.KG, Stuttgart 2009, ISBN 978-3-440-11736-1
  • Lawson Wood: Sea Fishes and Invertebrates of The Maltese Islands and The Mediterranean Sea, 2002
  • Helmut and Barbara Corneli: Diving Paradise Mediterranean, Stürtz Verlag, Würzburg 1993, ISBN 3-8003-0478-3

Web links

Commons : Flabellina affinis  - album with pictures, videos and audio files

Individual evidence

  1. ^ A b Louise Schmekel & Adolf Portmann (1982).
  2. http://www.marinespecies.org/aphia.php?p=taxdetails&id=139988
  3. Bergbauer Humberg: What lives in the Mediterranean? Franckh-Kosmos Verlags-GmbH & Co.KG, Stuttgart 2009, ISBN 978-3-440-11736-1
  4. http://www.meerwasser-lexikon.de/tiere/3231_Flabellina_affinis.htm