Dermatoxys veligera
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Male end of the body with alae, excretion porus and some papillae, ventral, scale 0.5 mm |
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| Dermatoxys veligera | ||||||||||||
| ( Rudolphi , 1819) |
Dermatoxys veligera is a nematode worm , the parasitic in the cecum of rabbit lives.
description
The body of adult worms is whitish and thread-shaped, the head has a slightly larger diameter than the following body section. The cuticle has transverse stripes that are about 5 micrometers apart in the middle of the body. The distances increase towards the ends of the body. The oral cavity has three lips, each with three papillae. At its rear end there are two ventrally and one dorsally one tooth. The esophagus consists of an anterior muscular and a posterior glandular section and ends in an eyeball without teeth. A nerve ring surrounds it about a third of its length. The excretion pore is small and occasionally barely visible. It is located almost at the end of the body and is surrounded on both sides by a pronounced papilla, behind the excretion pore there are another large and eight small papillae. The total number of eleven papillae is of taxonomic importance in distinguishing it from other species of the genus Dermatoxys .
Male worms are eight to 11.5 millimeters long and have a maximum diameter of about 435 micrometers, their tail is short and blunt. On the abdomen side there are ten to 17 transverse grooves in the middle of their body. The bursa copulatrix is formed by two elongated, wide, sail-like alae about 1.5 millimeters long, which are folded in towards the abdomen and meet at the conical end of the body. The spicules are very small and only weakly with a length of 85 microns chitinized . There is no gubernacle.
Female worms are 16 to 17 millimeters long with a maximum diameter of about 600 micrometers, about one sixth of the length is the tail. Your vulva is inconspicuous and is six to seven millimeters from the front end. An fallopian tube runs from it to just behind the excretion pore to the rear, where the two amphidelphic uteri are located. The thick-shelled eggs are longitudinally oval with a length of 110 millimeters and a diameter of 50 millimeters. They are slightly flattened on one side in the longitudinal direction.
The fourth instar larvae have a total of four strong hooks on the cuticle at the anterior end dorsolaterally and ventrolaterally , which are lost when molting into the adult nematode. Apart from that, their structure corresponds to that of adult worms.
distribution
Dermatoxys veligera occurs as an intestinal parasite of wild rabbits in much of the United States and from South America to Brazil. The parasite has been found in wild rabbits on the Iberian Peninsula and in desert hares and the Tolai hare in Asia . In Algeria it was found in a subspecies of the Kaphase ( Lepus capensis schlumbergeri ). Even domestic rabbits can act as hosts. Reports of finds in pigeons , notably the Alaskan pika , have been shown to misidentify the parasite. Two proofs of Dermatoxys veligera the Fleckenziesel were the only previous in a kind of squirrel (Sciuridae).
The prevalence is usually low and fluctuates between less than one percent and 60 percent depending on factors that have not been investigated in more detail. In this context, geographical, topographical or climatic differences between habitats were mentioned.
Way of life
Dermatoxys veligera lives parasitically in the appendix of rabbits (Leporidae), very rarely also in the small intestine. Adult specimens live freely in the lumen of the appendix, where they do not cause any symptoms even with severe infestation. A host's individual parasite load can exceed 100 worms. The fourth larval stage anchors itself with its hooks on the wall of the appendix and penetrates through the mucous membrane with the front end. In the places where the larvae sit, the tissue is necrotized by the larvae in a form of external digestion and opened up for their nutrition. Small ulcers may appear in these areas.
The life cycle corresponds to that of the pinworm . The males die after mating, the females leave the host's intestine through the anus to lay eggs . The infectious eggs, in which the first larval stage is already formed, are ingested orally by the shedder itself or by other hosts.
Systematics
Initial description
The first description of Dermatoxys veligera was carried out by the German physician and naturalist Karl Rudolphi in his 1819 in Berlin on Latin published work Synopsis entozoorum .
Rudolphi described the species under the name Ascaris veligera . Its description was based on worms from the intestines of Tapetis , which had been collected by the naturalists Ignaz von Olfers and Johann Natterer at the beginning of the Austrian expedition to Brazil .
etymology
The species name veligera is a combination of the Latin term velum (German: sail ) with the suffix -iger , derived from gerere (German: to carry ) , it means to carry a sail or to carry a sail and refers to the broad alae that form the bursa copulatrix .
Synonymy
Ascaris veligera Rudolphi , 1819: the extensive genus Ascaris wasdivided into numerous generaby Friedrich Anton Schneider in his monograph on nematodes in1866, including the monotypical Dermatoxys Schneider , 1866. This resulted in the combination Dermatoxys veligera , which is still valid today.
literature
- Karl Asmund Rudolphi: Synopsis entozoorum cui accedunt mantissa duplex et indices locupletissimi , August Rücker, Berlin 1819, p. 656, digitized (first description in Latin).
Web links
Individual evidence
- ↑ a b c d e Maurice C. Hall: Nematode parasites of mammals of the orders Rodentia, Lagomorpha, and Hyracoidea . In: Proceedings of the United States National Museum , 1916, Volume 50, pp. 1–258, here pp. 99–102, doi : 10.5479 / si.00963801.50-2131.1 .
- ↑ a b c d Anton Schneider : Monograph of the nematodes . Georg Reimer, Berlin 1866, pp. 123–124, panels XII and XXIV, digitized .
- ↑ F. Simón Vicente: On Dermatoxys hispaniensis n.sp. (Nematoda: Oxyuridea), from Oryctolagus cuniculus and Lepus timidus of Spain . In: Journal of Helminthology 1969, Volume 43, No. 3-4, pp. 417-426, doi : 10.1017 / S0022149X00004983 .
- ↑ a b c Stacy Pritt, Kimberley Cohen, and Heather Sedlacek: Parasitic Diseases . In: Mark A. Suckow, Karla A. Stevens and Ronald P. Wilson (Eds.): The Laboratory Rabbit, Guinea Pig, Hamster, and Other Rodents . Academic Press, New York 2012, ISBN 978-0-12-380920-9 , pp. 415-446, here p. 438, doi : 10.1016 / B978-0-12-380920-9.00015-8 .
- ↑ Gerard Dikmans: An Interesting Larval Stage of Dermatoxys veligera . In: Transactions of the American Microscopical Society 1931, Volume 50, No. 4, pp. 364-365, doi : 10.2307 / 3222077 .
- ^ A b Rudolph Wetzel : On the Biology of the Fourth-Stage Larva of Dermatoxys veligera (Rudolph 1819) Schneider 1866, an Oxyurid Parasitic in the Hare . In: Journal of Parasitology 1931, Volume 18, No. 1, pp. 40-43, doi : 10.2307 / 3271742 .
- ^ Arnold B. Erickson: The Snowshoe Hare a New Host of Dermatoxys veligera and Nematodirus leporis . In: Journal of Parasitology 1940, Volume 26, No. 5, p. 433, doi : 10.2307 / 3272487 .
- ^ Arnold B. Erickson: Helminth Parasites of Rabbits of the Genus Sylvilagus . In: Journal of Wildlife Management 1947, Volume 11, No. 3, pp. 255-263, doi : 10.2307 / 3796284 .
- ↑ a b c Karl Asmund Rudolphi: Synopsis entozoorum cui accedunt mantissa duplex et indices locupletissimi , August Rücker, Berlin 1819, p. 656, digitized .
- ↑ Pilar R. Foronda et al .: Helminths of the Wild Rabbit (Oryctolagus cuniculus) in Macaronesia . In: Journal of Parasitology 2003, Vol. 89, No. 5, pp. 952-957, doi : 10.1645 / GE-3048 .
- ↑ David S. Tinnin, Sumiya Ganzorig and Scott Lyell Gardner: Helminths of Small Mammals (Erinaceomorpha, Soricomorpha, Chiroptera, Rodentia, and Lagomorpha) of Mongolia . Special Publications Museum of Texas Tech University Number 59. Museum of Texas Tech University, Lubbock, Texas 2011, ISBN 978-1-929330-23-2 , digitized .
- ^ Léon Gaston Seurat: Sur l'existence en Algérie, du Dermatoxys veligera (Rud.) Et sur les affinités du genre Dermatoxys . In: Comptes rendus des séances de la Société de biologie et de ses filiales 1915, Volume 67, pp. 75–79, digitized .
- ↑ Eric P. Hoberg, Patricia A. Pilitt and Kurt E. Galbreath: Why Museums Matter: A Tale of Pinworms (Oxyuroidea: Heteroxynematidae) Among Pikas (Ochotona princeps and O. collaris) in the American West . In: Journal of Parasitology 2009, Volume 95, No. 2, pp. 490-501, doi : 10.1645 / GE-1823.1 .
- ↑ John E. Ubelaker et al .: Helminth Parasites of the Spotted Ground Squirrel, Xerospermophilus (syn. Spermophilus) spilosoma (Bennett, 1833) Helgen, Cole, Helgen, and Wilson, 2009, from Central New Mexico, USA In: Comparative Parasitology 2010, Volume 77, No. 2, pp. 178-182, doi : 10.1654 / 4398.1 .
- ^ Arnold B. Erickson: Helminth Infections in Relation to Population Fluctuations in Snowshoe Hares . In: Journal of Wildlife Management 1944, Volume 8, No. 2, pp. 134-153, doi : 10.2307 / 3796446 .
- ^ Gary S. Pfaffenberger and Viviana B. Valencia: Helminths of Sympatric Black-tailed Jack Rabbits (Lepus californicus) and Desert Cottontails (Sylvilagus audubonii) from the High Plains of Eastern New Mexico . In: Journal of Wildlife Diseases 1988, Volume 24, No. 2, pp. 375-377, doi : 10.7589 / 0090-3558-24.2.375 .
- ^ Charles L. Andrews, William R. Davidson, and Ernest E. Provost: Endoparasites of selected populations of cottontail rabbits (Sylvilagus floridanus) in the southeastern United States . In: Journal of Wildlife Diseases 1980, Volume 16, No. 3, pp. 395-401, doi : 10.7589 / 0090-3558-16.3.395 .
- ↑ Heinz Mehlhorn (Ed.): Encyclopedia of Parasitology , Fourth Edition. Springer, Berlin and Heidelberg 2016, p. 671 (Lemma Dermatoxys species ), doi : 10.1007 / 978-3-662-43978-4 .
- ↑ Trenton R. Schoeb et al .: Parasites of Rabbits . In: David G. Baker (Ed.): Flynn's parasites of laboratory animals . Second edition. Blackwell, Ames, Iowa 2007, pp. 451-499, here p. 486, ISBN 978-0-8138-1202-1 .
- ^ Alois Walde : Latin etymological dictionary , second revised edition. Carl Winter, Heidelberg 1910, Lemmata velum and gero , digitized .