Myxobdella annandalei

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Myxobdella annandalei
A, B: Nose gel (Dinobdella ferox), C, D: Myxobdella annandalei [1]

A, B:  Nose gel  ( Dinobdella ferox ), C, D:  Myxobdella annandalei

Systematics
Subclass : Bristle flukes (Euhirudinea)
Order : Trunkless leeches (Arhynchobdellida)
Subordination : Pine rule (Hirudiniformes)
Family : Praobdellidae
Genre : Myxobdella
Type : Myxobdella annandalei
Scientific name
Myxobdella annandalei
Oka , 1917

Myxobdella annandalei is the name of a kind in the fresh water of live leeches from the order of Kieferegel , who as endoparasite in the airways in mammals as well as human blood drawn. It is common in large parts of Asia .

features

Myxobdella annandalei reaches body lengths of around 5.5 cm and body widths of around 2.2 cm. A preserved specimen 5.2 cm long was - in the area of ​​the 22nd segment - up to 2.2 cm wide and up to 1.1 cm thick, in the throat area 3.5 mm wide, at the male genital opening 1.05 cm wide and 4 mm thick with the male genital opening 9 mm from the front end and the rear suction cup 1.65 cm in diameter. While the front end of the leech is slender and slightly flattened, the dorsally irregularly folded front suction cup is of medium size (between that of the blood-sucking nasal fluke and predatory horse leech ) and has a very flexible edge fold, while the central furrow is weakly developed or absent. Characteristic of the species is a small rounded papilla, which protrudes from the swollen mouth sail, the back wall of the front suction cup, into its cavity and at its tip bears the very small, three-part or triangular mouth opening. The segmentation of the leech can also be seen externally in adult specimens, as the furrows between the segments are deeper than between the outer ringlets within a segment. The segments of the middle body section do not have 5 outer ringlets continuously, as some furrows are very shallow or completely absent. The leech has a pale gray color and can be more or less densely drawn with black or blackish spots.

The eyes of the leech, which sit in five pairs of eyes on the 2nd to 6th segment, are small and therefore difficult to see. The very small, soft jaws are set in two rows (distichodont) with a few, each only 3 to 4 rudimentary teeth. The storage stomach (goiter) has a pair of well-developed blind sacs per segment, with the last, the postcaeca, being significantly elongated. Between the male genital opening in the 11th segment and the female in the 12th segment of the hermaphrodite animals there are 5 ringlets. The vagina has a blind sac. The clitellum is easily recognizable in larger animals through the hardened body walls with their thickened glandular layer and extends over 15 ringlets from the 10th to the 13th segment.

Distribution, habitat and way of life

Myxobdella annandalei is common in standing inland waters from India to China . It attacks the nasal cavities of humans and a wide variety of mammals, including domestic cattle and domestic dogs .

Life cycle

Myxobdella annandalei is, like all girdle worms, a hermaphrodite . Mating, in which two leeches mate each other, takes place in a body of water, for which the parasites have to leave their host. With the help of the clitellum, both partners form a cocoon and lay their eggs in it. Finished little leeches hatch out of the cocoon, waiting for the opportunity for a thirsty mammal to come and dip its nose into the water to become the host of this parasite.

Systematics

The Japanese zoologist Asajiro Oka chose the genus name Myxobdella "Schleim-Egel" ( ancient Greek μύξα mýxa "Schleim" and βδέλλα bdélla " Egel ") when he was describing the genus and the species at the same time . The specific epithet annandalei refers to the Scottish zoologist Thomas Nelson Annandale (1876-1924), who was in particular an entomologist and herpetologist , but also described the leech species Erpobdella concolor in an article in 1913 in an article on the fauna of the Sea of ​​Galilee .

literature

Individual evidence

  1. ↑ Anna J. Phillips, Renzo Arauco-Brown, Alejandro Oceguera-Figueroa, Gloria P. Gomez, María Beltrán, Yi-Te Lai, Mark E. Siddall (2010): Tyrannobdella rex n. Gen. N. Sp. and the evolutionary origins of mucosal leech infestations. PLoS One 5 (4), e10057. doi: 10.1371 / journal.pone.0010057 .