Spotted leafworm
| Spotted leafworm | ||||||||||||
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Phyllodoce maculata (right). A monograph of the British marine annelids , 1908. |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Phyllodoce maculata | ||||||||||||
| ( Linnaeus , 1767) |
The spotted leaf worm or spotted rowing worm ( Phyllodoce maculata ) is a marine annelid from the family of Phyllodocidae within the class of polychaete (Polychaeta) in the Arctic and northern Atlantic Ocean is widespread.
features
Phyllodoce maculata has a slender body up to 10 cm long with around 250 segments , which gradually decreases in width in the rear half of the body. The prostomium is long and has a more triangular shape. The eyes are medium in size. The proboscis has in its proximal section 12 - 6 on each side - longitudinal rows of 6 to 8, rarely 9 papillae, in the distal section 6 rows of more or less protruding nodules. The end ring has 16 to 18 papillae. The 1st segment cannot be seen from above and has two tentacles - cirrus - that extend to the 5th or 6th segment. The dorsal tentacle cirrus of the 2nd segment extends to about the 8th segment, the ventral tentacle cirrus to about the 5th segment. The dorsal tentacle cirrus of the 3rd segment extend approximately to the 7th or 8th segment. Aciculae are found in all tentacle cirrus except on the 1st segment. Bristles are present from the 3rd segment. The dorsal cirrus of the middle segments are rectangular, the lobes of the parapodia are rounded. The ventral cirrus is oval and longer than the lobes of the parapodia. The cirrus pygidium is five times as long as it is wide.
The prostomium has no noticeable dark pigmentation, and the 1st segment, which is only visible from below, is unpigmented. The second segment is also unpigmented dorsally or slightly pigmented on the posterior margin. The 3rd and 4th segments have a dark pigment that forms noticeable bands across the back. The tentacle cirrus often have subdistal dark spots. The areas of the back that appear to be segmented within each segment are also darkly spotted from the 5th segment. There are further pigmentations dorso-laterally on each segment, on the cirrus carriers of the dorsal cirrus and in the middle of the dorsal cirrus. There is a yellow pigment on the posterior portion of the prostomium and between the dorsal patches, especially behind. The eyes are dark reddish brown. In preserved animals, the dark pigmentation is usually well preserved, while the yellow disappears.
distribution and habitat
Phyllodoce maculata is common in the Arctic , the northern Atlantic Ocean , the English Channel , the North Sea , the Skagerrak , Kattegat , the Oresund and the western Baltic Sea . Due to their great similarity, especially with Phyllodoce mucosa , a reliable determination and therefore the delimitation of the distribution area is difficult.
habitat
Phyllodoce maculata lives on rocky ground, gravel and sand from the seashore to a depth of 400 m.
Development cycle
Phyllodoce maculata is sexually separated and forms swarms on the surface of the seabed when mating, with several males swarming around a female without changing shape. The egg cells are fertilized in the open sea. The green, gelatinous egg clutches are attached to stones or other hard substrate. The larvae develop through two free-floating Trochophora - and two Metatrochophora stadiums before leaving to sink down and crawling worms metamorphose .
Food and protection from enemies
Phyllodoce maculata feeds on the meat of dead animals such as dead molluscs, crabs and polychaetes as a scavenger , but also hunts living prey as a predator such as polychaetes, cordworms and barnacles . The polychaete grabs the prey with its evertable pharynx and devours it as a whole, as there are no jaws or teeth. Phyllodoce maculata protects itself against predators with a foul-tasting slime.
literature
- Gesa Hartmann-Schröder (1996): Annelida, Borstenwürmer, Polychaeta. Tierwelt Deutschlands 58, pp. 1–648, here p. 102, Phyllodoce .
- John D. Fish, Susan Fish: A Student's Guide to the Seashore . Cambridge University Press, Cambridge 2011. 540 pages. Phyllodoce maculata (Linnaeus) , p. 166.
Web links
- Phyllodoce maculata spotted leafworm , marine water lexicon
- MJ de Kluijver et al .: Phyllodoce maculata (Linnaeus, 1767). Macrobenthos of the North Sea - Polychaeta, Marine Species Identification Portal
- Phyllodoce maculata . AG Benthic Organisms, Warnemünde.