Millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name derived from this feature. Each double-legged segment is a result of two single segments fused together. Most millipedes have very elongated cylindrical or flattened bodies with more than 20 segments, while pill millipedes are shorter and can roll into a tight ball. Although the name "millipede" derives from Latin for "thousand feet", no species was known to have 1,000 or more until the discovery in 2020 of Eumillipes persephone, which can have over 1,300 legs. There are approximately 12,000 named species classified into 16 orders and around 140 families, making Diplopoda the largest class of myriapods, an arthropod group which also includes centipedes and other multi-legged creatures.
Most millipedes are slow-moving detritivores, eating decaying leaves and other dead plant matter. Some eat fungi or drink plant fluids, and a small number are predatory. Millipedes are generally harmless to humans, although some can become household or garden pests. Millipedes can be an unwanted nuisance particularly in greenhouses where they can potentially cause severe damage to emergent seedlings. Most millipedes defend themselves with a variety of chemicals secreted from pores along the body, although the tiny bristle millipedes are covered with tufts of detachable bristles. Its primary defence mechanism is to curl into a tight coil, thereby protecting its legs and other vital delicate areas on the body behind a hard exoskeleton. Reproduction in most species is carried out by modified male legs called gonopods, which transfer packets of sperm to females.
First appearing in the Silurian period, millipedes are some of the oldest known land animals. Some members of prehistoric groups, such as Arthropleura, grew to over 2 m (6+1⁄2 ft); the largest modern species reach maximum lengths of 27 to 38 cm (10+1⁄2 to 15 in). The longest extant species is the giant African millipede (Archispirostreptus gigas).
Among myriapods, millipedes have traditionally been considered most closely related to the tiny pauropods, although some molecular studies challenge this relationship. Millipedes can be distinguished from the somewhat similar but only distantly related centipedes (class Chilopoda), which move rapidly, are venomous, carnivorous, and have only a single pair of legs on each body segment.
The scientific study of millipedes is known as diplopodology, and a scientist who studies them is called a diplopodologist.
The term "millipede" is widespread in popular and scientific literature, but among North American scientists, the term "milliped" (without the terminal e) is also used. Other vernacular names include "thousand-legger" or simply "diplopod". The science of millipede biology and taxonomy is called diplopodology: the study of diplopods.
Millipedes are among the first animals to have colonised land during the Silurian period. Early forms probably ate mosses and primitive vascular plants. There are two major groups of millipedes whose members are all extinct: the Archipolypoda ("ancient, many-legged ones") which contain the oldest known terrestrial animals, and Arthropleuridea, which contain the largest known land invertebrates. Earliest known fossils of millipedes are Kampecaris obanensis and Archidesmus sp. from 425 millions years ago in the late Silurian. Pneumodesmus newmani, once considered as the earliest member but later reconsidered that is from 414 million years ago in the early Devonian, was an archipolypodan known from 1 cm (1⁄2 in) long fragment and has clear evidence of spiracles (breathing holes) attesting to its air-breathing habits. During the Upper Carboniferous (340 to 280 million years ago), Arthropleura became the largest known land-dwelling invertebrate on record, reaching lengths of at least 2 m (6+1⁄2 ft). Millipedes also exhibit the earliest evidence of chemical defence, as some Devonian fossils have defensive gland openings called ozopores. Millipedes, centipedes, and other terrestrial arthropods attained very large sizes in comparison to modern species in the oxygen-rich environments of the Devonian and Carboniferous periods, and some could grow larger than one metre. As oxygen levels lowered through time, arthropods became smaller. @selyan1980
#millipede
#millipedes
#shorts
Most millipedes are slow-moving detritivores, eating decaying leaves and other dead plant matter. Some eat fungi or drink plant fluids, and a small number are predatory. Millipedes are generally harmless to humans, although some can become household or garden pests. Millipedes can be an unwanted nuisance particularly in greenhouses where they can potentially cause severe damage to emergent seedlings. Most millipedes defend themselves with a variety of chemicals secreted from pores along the body, although the tiny bristle millipedes are covered with tufts of detachable bristles. Its primary defence mechanism is to curl into a tight coil, thereby protecting its legs and other vital delicate areas on the body behind a hard exoskeleton. Reproduction in most species is carried out by modified male legs called gonopods, which transfer packets of sperm to females.
First appearing in the Silurian period, millipedes are some of the oldest known land animals. Some members of prehistoric groups, such as Arthropleura, grew to over 2 m (6+1⁄2 ft); the largest modern species reach maximum lengths of 27 to 38 cm (10+1⁄2 to 15 in). The longest extant species is the giant African millipede (Archispirostreptus gigas).
Among myriapods, millipedes have traditionally been considered most closely related to the tiny pauropods, although some molecular studies challenge this relationship. Millipedes can be distinguished from the somewhat similar but only distantly related centipedes (class Chilopoda), which move rapidly, are venomous, carnivorous, and have only a single pair of legs on each body segment.
The scientific study of millipedes is known as diplopodology, and a scientist who studies them is called a diplopodologist.
The term "millipede" is widespread in popular and scientific literature, but among North American scientists, the term "milliped" (without the terminal e) is also used. Other vernacular names include "thousand-legger" or simply "diplopod". The science of millipede biology and taxonomy is called diplopodology: the study of diplopods.
Millipedes are among the first animals to have colonised land during the Silurian period. Early forms probably ate mosses and primitive vascular plants. There are two major groups of millipedes whose members are all extinct: the Archipolypoda ("ancient, many-legged ones") which contain the oldest known terrestrial animals, and Arthropleuridea, which contain the largest known land invertebrates. Earliest known fossils of millipedes are Kampecaris obanensis and Archidesmus sp. from 425 millions years ago in the late Silurian. Pneumodesmus newmani, once considered as the earliest member but later reconsidered that is from 414 million years ago in the early Devonian, was an archipolypodan known from 1 cm (1⁄2 in) long fragment and has clear evidence of spiracles (breathing holes) attesting to its air-breathing habits. During the Upper Carboniferous (340 to 280 million years ago), Arthropleura became the largest known land-dwelling invertebrate on record, reaching lengths of at least 2 m (6+1⁄2 ft). Millipedes also exhibit the earliest evidence of chemical defence, as some Devonian fossils have defensive gland openings called ozopores. Millipedes, centipedes, and other terrestrial arthropods attained very large sizes in comparison to modern species in the oxygen-rich environments of the Devonian and Carboniferous periods, and some could grow larger than one metre. As oxygen levels lowered through time, arthropods became smaller. @selyan1980
#millipede
#millipedes
#shorts
- Catégories
- Chats de Race American Curl
- Mots-clés
- milliped, millipedes
Commentaires