Awls

from Wikipedia, the free encyclopedia
Awls
Thyca ectoconcha sucks on Linckia multifora

Thyca ectoconcha sucks on Linckia multifora

Systematics
Superordinate : Caenogastropoda
Order : Sorbeoconcha
Subordination : Hypsogastropoda
Partial order : Littorinimorpha
Superfamily : Vanicoroidea
Family : Awls
Scientific name
Eulimidae
Philippi , 1853
Parasitic snails, perhaps Melanella sp., On a young Holothuria verrucosa
Stilifer linckiae parasitizes in Linckia multifora with gall formation, Réunion
Housing of Melanella candida

The awl snails ( Eulimidae ) are a species-rich family of very small to small, exclusively marine snails , which are distributed worldwide. They live as ectoparasites , less often than endoparasites , almost exclusively on or in echinoderms .

features

The right-hand winding, elongated conical or spindle-shaped housing of the Eulimidae have a smooth, very shiny surface and a drawn-out thread with numerous flat, flat-sided circumferences. The egg-shaped housing mouth has an unconnected mouth seam. The spindle is not toothed. For most species, the casing is no longer than 5 mm, for some species up to 14 mm.

The mostly colorless housings are translucent in the living animal and when fresh, so that one can see the inner structures of the house and the animal. When looking at the thread, you can see inner boundaries of the perimeter, so-called false seams. To see the actual seams, light reflected on the surface is required. The same applies to the appearance of the weakly pronounced sculpture: growth stripes and spiraling lines.

The horny operculum has only a few turns.

The snails have long, slender, cylindrical antennae and a long, extendable proboscis , which they bore into their host animals. There is no radula (hence the older names Aglossa and Gymnoglossa). The front of the foot is provided with a large anterior mucous gland. In less strongly derived Eulimidae, the foot is long and slender with a well-developed propodium . Many species of the family have a collar-like protuberance around their mouth, the pseudopallium ( pseudopallium ), which in some endoparasitic snails can cover the entire shell.

The morphology of the screw varies in this family very greatly depending on the host animal, which is usually a type of sea cucumbers , sea urchins , starfish and brittle stars is. The snail is usually permanently anchored to its host through its snout or proboscis.

The snails are separate sexes with internal fertilization. Many representatives of the family show a pronounced sexual dimorphism, in which the males are a tenth to 0.7 times the size of the females. In most cases, the eggs hatch Veliger larvae, which go through a longer phase than zooplankton and feed on plankton. However, there are also species with direct development, in which the embryos are fed with yolk and ready-made snails hatch from the egg capsules. Both types of development occur in the genus Melanella .

Occurrence, distribution and species examples with host animals

The Eulimidae are common in all tropical, subtropical, temperate, arctic and Antarctic seas. They live in shallow water as well as in great depths up to the abyssal .

In the North Sea lives among other Eulima bilineata that of brittle stars ( Ophiothrix fragilis , Ophiactis ballistic , Ophiopholis aculeata sucks). Another Ectoparasite of brittle stars in the Mediterranean and eastern Atlantic Ocean to the British Isles spread Eulima glabra . The on the Galapagos Islands living Eulima encopicola parasitized on Sand Dollar Encope micropora . The snails of the genus Echineulima live on sea urchins , the order Reunion living Echineulima eburnea to Heterocentrotus trigonarius . Curveulima shop landi is again at the bottom of the Indo-Pacific frequent nodular rolling starfish ( Protoreaster nodosus to find). Representatives of the genus Parvioris live exclusively on starfish , while snails of the genus Melanella parasitize on sea ​​cucumbers , such as Melanella lubrica and Melanella alba , which also live in the North Sea - the latter on Neopentadactyla mixta , among others - and Melanella polita, which is common in the Mediterranean and Eastern Atlantic, on various holothurias . In the genus Vitreolina , parasitism occurs in sea urchins as well as brittle stars and sea cucumbers. Vitreolina philippi , which can also be found in the German Bight and the Baltic Sea , seems to prefer the stone sea urchin ( Paracentrotus lividus ) in the Mediterranean , but it can also be found on the beach sea ​​urchin ( Psammechinus miliaris ). The snails of the genera Thyca and Stilifer attack starfish, the former as ectoparasites and the latter as partially endoparasites. The comet star ( Linckia multifora ) of the Indo-Pacific is attacked by three common parasites from the Eulimidae family: While Thyca ectoconcha and Thyca crystallina sit on the underside of the starfish on the skin and pierce it as an ectoparasite with their proboscis, Stilifer linckiae penetrates completely Starfish and live as an endoparasite protected in an arm under the skin, which swells into a bile, whereby the snail still has access to the outside water through an opening. In the sun star-like starfish Heliaster cumingi, the snail Stilifer astericola parasitizes in a similar way . The Echiuroidicola cicatricosa found in Malaysia , which parasitizes the hedgehog worm Ochetostoma erythrogrammon, is an exception with regard to the host animal within the Eulimidae .

Entirely to an internal parasitic adapted lifestyle Entoconcha mirabilis , in the Klettenholothurie Oestergrenia digitata in Mediterranean living. Only the young can still be recognized as a snail, whereas the adult female has the shape of a simple tube. The biology of this snail was first studied by Johannes Peter Müller and then Albert Baur in the 19th century . The snails of the genera Entocolax and Enteroxenos , which also live in sea cucumbers, such as Entocolax ludwigii , which parasitizes the sea cucumber species Myriotrochus rinkii , are similarly adapted to life as an endoparasite . Also quite endoparasitic, but in starfish, are the snails of the genus Asterophila with the species Asterophila japonica , which is common in the western Pacific and is found in various species of starfish, including Leptychaster anomalus and Ctenodiscus crispatus .

Systematics

According to Bouchet and Rocroi (2005), the Eulimidae family and the Aclididae GO Sars family formed the superfamily Eulimoidea in 1878 . The Eulimidae family has several hundred species in around 101 genera.

The family Entoconchidae Keferstein 1864, in which the genera Entoconcha and Entocolax are summarized by some authors , is a synonym of Eulimidae according to Bouchet.

literature

  • Stephan Clessin: The family of the Eulimidae. Systematic Conchylia Cabinet. Verlag von Bauer & Raspe, Nuremberg 1902.
  • Michel Jangoux (1981): Diseases of Echinodermata. 11. Agents metazoans (Mesozoa to Bryozoa) (PDF; 4.1 MB) . Diseases of Aquatic Organisms 2, pp. 205-234. Eulimidae : pp. 218-228.
  • Anders Warén: A Generic Revision of the Family Eulimidae (Gastropoda, Prosobranchia). Journal of Molluscan Studies 49 (Supplement 13), pp. 1-96, 1983, here pp. 76-80. doi: 10.1093 / mollus / 49.Supplement_13.1
  • Enzo Campani: Eulimidae Mediterranee (PDF; 1.5 MB) . Documenti del Gruppo Malacologico Livornese, 2001 (Italian).
  • Enzo Campani: La Famiglia Eulimidae in Mediterraneo (PDF; 4.0 MB) . Documenti del Gruppo Malacologico Livornese, 1999 (Italian).
  • John W. Tunnell, Jean Andrews, Noe C Barrera, Fabio Moretzsohn: Encyclopedia of Texas Seashells: Identification, Ecology, Distribution, and History . Texas A&M University Press, College Station (Texas) 2010. 512 pp. Eulimidae : p. 196.
  • Alastair Graham, Alastair Graham (FRS): Molluscs: Prosobranch and Pyramidellid Gastropods. Keys and Notes for the Identification of the Species . Linnean Society, London 1988. Eulimidae H. & A. Adams, 1853 : p. 516.
  • Philippe Bouchet & Jean-Pierre Rocroi: Part 2. Working classification of the Gastropoda . Malacologia, 47: 239-283, Ann Arbor 2005 ISSN  0076-2997
  • Winston Ponder & David Lindberg, Towards a phylogeny of gastropod molluscs; an analysis using morphological characters . Zoological Journal of the Linnean Society, 119: 83-265, London 1997 ISSN  0024-4082
  • Frank Riedel: Origin and evolution of the "higher" Caenogastropoda . Berliner Geoscientific Abhandlungen, Series E, Volume 32, Berlin 2000, 240 pages, ISBN 3-89582-077-6 .

Web links

Commons : Eulimidae  - Collection of images, videos and audio files

Individual evidence

  1. ↑ Ivan O. Nekhaev (2011): Two species of parasitic molluscs new for Russian seas (PDF; 1.0 MB) . Ruthenica 21 (1), pp. 69-72.
  2. ↑ Heinke Schultz, Shirtingen (2005), p. 5.
  3. ↑ Heinke Schultz, Shirtingen (2005): Interactions between mollusks and sea urchins (PDF; 3.7 MB), p. 4.
  4. ^ Shell Encyclopedia :: List View - Curveulima shoplandi
  5. ↑ Danilo Scuderi, Francesco Criscione (2011): New ecological and taxonomical data on some Ptenoglossa (Mollusca, Caenogastropoda) from the Gulf of Catania (Ionian Sea) (PDF; 4.8 MB) . Biodiversity Journal, 2 (1), pp. 35-48.
  6. ↑ Constantine Mifsud (1990): Vitreolina philippi (Ponzi, de Rayneval & van den Heck, 1854) found living on the echinoid Paracentrotus lividus (Lamarck) in infralittoral Maltese waters. Bolletino Malacologico 26, pp. 165-168.
  7. ^ A. Bertrand: Four specimens living on the dorsal face of a Psammechinus miliaris (PLS Müller, 1771), seen at low tide, among rocks, Saint-Jean-de-Luz, Iparraide, SW France.
  8. ^ Thomas WM Cameron: Parasites and Parasitism . Wiley, New York 1956. pp. 199-201.
  9. ↑ a b D. R. Khanna: Biology Of Mollusca . Discovery Publishing House, Delhi 2004. 19. Parasitism . Pp. 300-304. ISBN 8171418988 .
  10. ↑ Anders Warén: Revision of the Genera Thyca, Stilifer, Scalenostoma, Mucronalia and Echineulima (Mollusca, Prosobranchia, Eulimidae). Zoologica Scripta 9, 1980, pp. 187-210.
  11. ^ Philip Henry Gosse (1854). Natural history - Mollusca . P. 192. Here Stylifer astericola and Asterias Solaris : According to Christopher Mah (2009), WoRMS is Asterias solaris Carpenter, 1856 synonym of Heliaster cumingi (Gray, 1840) ; This is not about the homonym Asterias solaris Schreber , 1793, which, according to Christopher Mah (2017), WoRMS, is a synonym of Acanthaster planci (Linnaeus, 1758).
  12. ↑ Anders Waren (1980): Descriptions of New Taxa of Eulimidae (Mollusca, Prosobranchia), with Notes on Some Previously Described Genera . Zoologica Scripta 9, pp. 283-306.
  13. ↑ in Baur : Synapta digitata Montagu, 1815 , according to G. Paulay (2012), World Register of Marine Species : Oestergrenia digitata (Montagu, 1815)
  14. ^ Alfred Brehm : Brehms Thierleben . General customer of the animal kingdom. Great edition . Volume 10. Bibliographical Institute, Leipzig / Vienna 1893. Holothuria snail tube . Pp. 406-410 .
  15. ↑ T. Sasaki, K. Muro, M. Komatsu: Anatomy and ecology of the shell-less endoparasitic gastropod Asterophila japonica Randall and Heath, 1912 (Mollusca: Eulimidae). In: Zoological science. Volume 24, Number 7, July 2007, pp. 700-713, doi : 10.2108 / zsj.24.700 , PMID 17824778 .
  16. ^ World Register of Marine Species , Eulimidae Philippi, 1853
  17. ↑ Andreas Altnöder, Jens Michael Bohn, Ina-Maria Rückert, Enrico Schwabe (2007): The presumed shelled juvenile of the parasitic gastropod Entocolax schiemenzii Voigt, 1901 and its holothurian host Chiridota pisanii Ludwig, 1886 (Gastropoda, Entoconchidae - Holothuroidea), Chiridotidae ( Memento of the original from January 30, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 781 kB) . Spixiana 30 (2), pp. 187-199.  @1@ 2Template: Webachiv / IABot / www.fundacionhuinay.cl
  18. ↑ World Register of Marine Species , Entoconchidae Keferstein, 1864