Millipede
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 Rusty millipede (Trigoniulus corallinus)
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Helminthomorpha |
Millipedes (Class Diplopoda, previously also known as Chilognatha) are very elongated arthropods with cylindrical bodies that have two pairs of legs for each one of their 20 to 100 or more body segments (except for the first segment behind the head which does not have any appendages at all, and the next few which only have one pair of legs). Each segment that has two pairs of legs is a result of two single segments fused together as one. This class contains around 10,000 species. The Giant African Millipede is the largest species of millipede. These animals are detritivores, slow and nonvenomous; unlike the somewhat similar and closely related centipedes (Class Chilopoda), which can be easily distinguished by their single pair of legs for each body segment. Most millipedes eat decaying leaves and other dead plant matter, moisturizing the food with secretions and then scraping it in with the jaws. However they can also be a minor garden pest, especially in greenhouses where they can cause severe damage to emergent seedlings. Signs of millipede damage include the stripping of the outer layers of a young plant stem and irregular damage to leaves and plant apices.
This class of arthropods is thought to be among the first animals to colonize land during the Silurian geologic period. These early forms probably ate mosses and primitive vascular plants.
Indeed, the very oldest known land animal, Pneumodesmus newmani, was a centimeter-long millipede.
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[edit] Characteristics
The millipede's most obvious feature is its large number of legs. In fact, its name is a compound word formed from the Latin roots milli ("thousand") and ped ("foot"). Despite their name, these creatures do not have a thousand legs, although the rare species Illacme plenipes have up to 750.[1] However, common species have between 80 and 400 legs.
Having very many short legs makes millipedes rather slow, but they are powerful burrowers. With their legs and body length moving in a wavelike pattern, they easily force their way underground head first. They also seem to have some engineering ability, reinforcing the tunnel by rearranging the particles around it.
The head contains a pair of sensory organs known as the Tömösváry organs. These are found just posterior and lateral to the antennae, and are shaped as small and oval rings at the base of the antennae. They are probably used to measure the humidity in the surroundings, and they may have some chemoreceptory abilities too.
Some millipede species may be amphibious.
[edit] Defense mechanisms
Due to their lack of speed and their inability to bite or sting, millipedes' primary defense mechanism is to curl into a tight coil—protecting their delicate legs inside an armored body exterior. Many species also emit poisonous liquid secretions or hydrogen cyanide gas through microscopic pores along the sides of their bodies as a secondary defense.[2][3][4] Some of these substances are caustic and can burn the exoskeleton of ants and other insect predators, and the skin and eyes of larger predators. Lemurs have been observed intentionally irritating millipedes in order to rub the chemicals on themselves to repel insect pests, and possibly to produce a psychoactive effect.
As far as humans are concerned, this chemical brew is fairly harmless, usually causing only minor effects on the skin, the main effect being discoloration, but other effects may also include pain, itching, local erythema, edema, blisters, eczema, and occasionally cracked skin.[3][5][6][7] Eye exposures to these secretions causes general eye irritation and potentially more severe effects such as conjunctivitis and keratitis.[8] First aid consists of flushing the area thoroughly with water, further treatment is aimed at relieving the local effects.
[edit] Millipedes as pets
Many millipedes are quite docile and may safely be kept as pets and handled without risk of injury. The Giant African Millipede-Archispirostreptus gigas is a common pet millipede. These can be found at pet stores for reasonable prices. Sometimes you can buy very similar millipedes under the name Lophostreptus rutilans but in most cases it is just Archispirostreptus gigas . With the proper caging and feeding, pet millipedes can live up to about 7 years and grow to be as long as 15 inches.
[edit] Gallery
 Pill Millipede, Western Ghats, India |
 Sri Lankan Giant Millipede |
 A number of millipedes - found under a rock |
 Small backyard millipede, Sydney, Australia |
 Giant African Millipede |
 Mating Giant Millipede |
[edit] References
- ^ See "Most leggy millipede rediscovered" BBC News, 8 June 2006
- ^ Blum & Woodring. 1962. Secretion of Benzaldehyde and Hydrogen Cyanide by the Millipede Pachydesmus crassicutis. Science 138:513.
- ^ a b Mason G, Thompson H, Fergin P, Anderson R (1994). "The burning millipede". Med J Aust 160: 718, 726.
- ^ Kuwahara Y, Omura H, Tanabe T (2002). "2-Nitroethenylbenzenes as natural products in millipede defense secretions". Naturwissenschaften 89 (7): 308-10. PMID 12216861.
- ^ Shpall S, Frieden I (1991). "Mahogany discoloration of the skin due to the defensive secretion of a millipede". Pediatr Dermatol 8 (1): 25-7. PMID 1862020.
- ^ Radford A (1976). "Giant millipede burns in Papua New Guinea". P N G Med J 18 (3): 138-41. PMID 1065155.
- ^ Radford A (1975). "Millipede burns in man.". Trop Geogr Med 27 (3): 279-87. PMID 1103388.
- ^ Hudson B, Parsons G. "Giant millipede 'burns' and the eye". Trans R Soc Trop Med Hyg 91 (2): 183-5. PMID 9196764.
[edit] See also
- Order Spirobolida - Narceus americanus
[edit] External links
- Photo gallery of millipedes.
- blue Polydesmid millipede - Picture taken in Veracruz, Mexico.
- American Millipede [1][2]- Photos of American Millipede
