Lennogaster chittagongensis
| Lennogaster chittagongensis | ||||||||||||
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| Lennogaster chittagongensis | ||||||||||||
| ( J.Stephenson , 1917) |
Lennogaster chittagongensis is a little bristle of the genus Lennogaster in the family Octochaetidae . The species was discovered in the Rangamati District in the Chittagong Division in southeastern Bangladesh , but is common in large parts of Myanmar and northern India .
description
The largely unpigmented body of Lennogaster chittagongensis has 79 to 138 segments, 121 segments according to the first description, the reddish or brownish clitellum extends from the 13th to the 17th segment. The body length is between 24 and 78 millimeters, with a diameter of one to, in the area of the clitellum, two millimeters. The prostomium extends with a tongue-shaped extension up to half of it into the peristomium . The digestive system does not have an appendix; there are large chewing stomachs in segments five and six . The segments 10 to 12 have vertically egg-shaped calcareous glands arranged in pairs, which open into pores in the side walls of the esophagus. The Typhlosolis is enlarged at the rear end. The last heart is in the 12th segment. In the 17th segment are two prostatic glands.
In segment 8 there are two semen bags (sperm counters) in which sperm has never been found. Therefore, it is assumed that Lennogaster chittagongensis be parthenogenetic increased. However, the eighth segment has copulatory bristles that are 0.22-0.30 mm long, eleven to fourteen micrometers in diameter. The testes are limited to the 10th segment, but there are seminal ducts in the 11th segment. The penial setae of segments 18 and 19 are S-shaped and have several transverse rows of fine teeth near the body. They are 0.5 to 0.64 millimeters in length and three to six micrometers in diameter at the base and two to three micrometers at the top. The ovaries are located in the 13th segment, and in the 14th segment there is a pair of large egg sacs. The eggs are unusually large for the size of the worms.
distribution
The type location is the Rangamati district ( 22 ° 36 ′ 0 ″ N , 92 ° 12 ′ 0 ″ E ) in the Chittagong Hill Tracts of the Chittagong Division in southeast Bangladesh . The species is widespread in Myanmar , especially in the center of the country. Its natural range seems to extend from there over the Chittagong Hill Tracts to the northeast Indian state of Tripura and possibly neighboring states. Finds from the Indian states of Himachal Pradesh , Jammu and Kashmir and West Bengal became known at the end of the 20th century . The specimens found there may have been introduced with plants or in some other way.
There is evidence of Lennogaster chittagongensis from plantations with rubber trees , various types of bamboo and tea , but also from nurseries, lawns, landfills or composting plants where the worms live ten to thirty centimeters deep. Compared to the sympatric exotic species, the species has a low tolerance to temperature, moisture, nutrient or acid content of the soil. It always makes up only a small part of the oligochaic fauna.
Systematics and taxonomy
Lennogaster chittagongensis is one of about half a dozen species of the genus Lennogaster Gates , 1939, which is distributed from Myanmar to Bangladesh to northern India. It belongs to the Octochaetidae family with about thirty other genera , which in turn belongs to the order of earthworms in the broader sense .
It was first described in 1917 by the British surgeon and zoologist John Stephenson from Government College in Lahore in the Records of the Indian Museum . Stephenson described several new species from recent additions to the Indian Museum's collection , including Eudichogaster chittagongensis . For the description, Stephenson had two copies that had been collected at the type location in July 1915. The type material is in the collection of the Indian Museum in Kolkata . The species name refers to the Chittagong Hill Tracts as the first site.
In 1939, as part of his revision of the genus Eudichogaster , the American zoologist Gordon E. Gates set up the new genus Lennogaster , in which he also included Lennogaster chittagongensis .
synonym
- Eudichogaster chittagongensis J.Stephenson , 1917
Individual evidence
- ^ A b c d John Stephenson: On a collection of Oligochaeta from various parts of India and further India . In: Records of the Indian Museum 1917, Volume 13, pp. 353-416, plates XVI-XVIII, here pp. 411-413, digitized .
- ^ A b c d Gordon E. Gates: Indian earthworms. VII. Contribution to a revision of the genus Eudichogaster . In: Records of the Indian Museum 1939, Volume 41, pp. 151-218, digitized .
- ^ A b c Gordon E. Gates: Burmese Earthworms: An Introduction to the Systematics and Biology of Megadrile Oligochaetes with Special Reference to Southeast Asia . In: Transactions of the American Philosophical Society 1972, Vol. 62, No. 7, pp. 1-326, doi: 10.2307 / 1006214 .
- ^ John Warren Reynolds: The earthworms of Bangladesh (Oligochaeta: Megascolecidae, Moniligastridae and Octochaetidae) . In: Megadrilogica 1994, Volume 5, No. 4, pp. 33-44, ISSN 0380-9633 .
- ^ KR Halder, S. Dhani and CK Mandal: On some earthworms present in unnamed collections of Zoological Survey of India . In: Records of the zoological Survey of India 2007, Volume 107, Part 3, pp. 79-93, digitized version (entire partial volume).
- ^ Sourabh Chakraborty and PS Chaudhuri: Earthworm Communities in the Bamboo Plantations of West Tripura (India) . In: Proceedings of the Zoological Society 2017, Volume 70, No. 2, pp. 105-118, doi: 10.1007 / s12595-015-0164-5 .
- ↑ PS Chaudhuri, Sabyasachi Nath and Rahul Paliwal: Earthworm population of rubber plantations (Hevea brasiliensis) in Tripura, India . In: Tropical Ecology 2008, Volume 49, No. 2, pp. 225-234, digitized .
- ^ PS Chaudhuri and Sourabh Chakraborty: Impact of five different species of bamboo plantations on earthworm communities in West Tripura (India) . In: Records of the zoological Survey of India 2019, Volume 119, No. 1, pp. 18–33, digitized .
- ↑ SKS Jamatia and PS Chaudhuri: Earthworm community structure under tea plantations (Camellia sinensis) of Tripura (India) . In: Tropical Ecology 2017, Volume 58, No. 1, pp. 105-113, digitized .
- ^ Gordon E. Gates: On Burmese earthworms of the Megascolecid subfamily Octochaetinae . In: Annals and Magazine of Natural History 1958, Series 13, Volume 1, No. 9, pp. 609-624, doi: 10.1080 / 00222935808650990 .