Millipede in the context of "Greenhouse"

Myriapods (from Ancient Greek μυρίος (muríos) 'countless' and πούς (poús) 'foot') are the members of subphylum Myriapoda, containing arthropods such as millipedes and centipedes. The group contains about 13,000 species, all of them terrestrial.

Although molecular evidence and similar fossils suggests a diversification in the Cambrian Period, the oldest known fossil record of myriapods dates between the Late Silurian and Early Devonian, with Pneumodesmus preserving the earliest known evidence of air-breathing on land. Other early myriapod fossil species around the similar time period include Kampecaris obanensis and Archidesmus sp. The phylogenetic classification of myriapods is still debated.

Reginald Innes Pocock, F.R.S. (4 March 1863 – 9 August 1947) was a British zoologist.

Pocock was born in Clifton, Bristol, the fourth son of Rev. Nicholas Pocock and Edith Prichard. He began showing interest in natural history at St. Edward's School, Oxford. He received tutoring in zoology from Sir Edward Poulton, and was allowed to explore comparative anatomy at the Oxford Museum. He studied biology and geology at University College, Bristol, under Conwy Lloyd Morgan and William Johnson Sollas. In 1885, he became an assistant at the Natural History Museum, and worked in the section of entomology for a year. He was put in charge of the collections of Arachnida and Myriapoda. He was also given the task of arranging the British bird collections, in the course of which he developed a lasting interest in ornithology. The 200 papers he published in his 18 years at the museum soon brought him recognition as an authority on Arachnida and Myriapoda; he described between 300 and 400 species of millipedes alone, and also described the scorpion genus Brachistosternus. In 1929, he proposed the family Nandiniidae, with the genus Nandinia as its sole member. He argued that it differs from the Aeluroidea by the structure and shape of its ear canal and mastoid part of the temporal bone.

The compound eyes of arthropods like insects, crustaceans and millipedes are composed of units called ommatidia (sg.: ommatidium). An ommatidium contains a cluster of photoreceptor cells surrounded by support cells and pigment cells. The outer part of the ommatidium is overlaid with a transparent cornea. Each ommatidium is innervated by one axon bundle (usually consisting of 6–9 axons, depending on the number of rhabdomeres) and provides the brain with one picture element. The brain forms an image from these independent picture elements. The number of ommatidia in the eye depends upon the type of arthropod and range from as low as five as in the Antarctic isopod Glyptonotus antarcticus, or a handful in the primitive Zygentoma, to around 30,000 in larger Anisoptera dragonflies and some Sphingidae moths.

The clade Mandibulata constitutes one of the major subdivisions of the phylum Arthropoda, alongside Chelicerata. Mandibulates include the crustaceans, myriapods (centipedes and millipedes, among others), and all true insects. The name "Mandibulata" refers to the mandibles, a modified pair of limbs used in food processing, the presence of which are characteristic of most members of the group.

The mandibulates are divided between the extant groups Myriapoda (millipedes and centipedes, among others) and Pancrustacea (including crustaceans and hexapods, the latter group containing insects). Molecular phylogenetic studies suggest that the living arthropods are related as shown in the cladogram below. Crustaceans do not form a monophyletic group as insects and other hexapods have evolved from within them.

Centipedes (from Neo-Latin centi-, "hundred", and Latin pes, pedis, "foot") are predatory arthropods belonging to the class Chilopoda (Ancient Greek χεῖλος, kheilos, "lip", and Neo-Latin suffix -poda, "foot", describing the forcipules) of the subphylum Myriapoda, an arthropod group which includes millipedes and other multi-legged animals. Centipedes are elongated segmented (metameric) animals with one pair of legs per body segment. All centipedes are venomous and can inflict painful stings, injecting their venom through pincer-like appendages known as forcipules or toxicognaths, which are actually modified legs instead of fangs. Despite the name, no species of centipede has exactly 100 legs; the number of pairs of legs is an odd number that ranges from 15 pairs to 191 pairs.

Centipedes are predominantly generalist carnivorous, hunting for a variety of prey items that can be overpowered. They have a wide geographical range, which can be found in terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist microhabitat because they lack the waxy cuticle of insects and arachnids, causing them to rapidly lose water. Accordingly, they avoid direct sunlight by staying under cover or by being active at night.

Kampecaris is an extinct genus comprising the Kampecarida, an enigmatic group of millipede-like arthropods, from the Silurian and early Devonian periods of Scotland and England. They are among the oldest known land-dwelling animals. They were small (20–30 millimetres (0.79–1.18 in) long), short-bodied animals with three recognizable sections: an oval head divided along the midline, ten limb-bearing segments forming a cylindrical trunk that tapered slightly towards the front, and a characteristic swollen tail formed by a modified segment that tapers at its rear into an "anal segment". The cuticle forming their exoskeletons was thick, heavily calcified, and composed of two layers.

The genus was named by David Page in 1856 for a "small phyllopod, or the larval stage of some larger crustacean" from Silurian deposits of Angus, Scotland (formerly Forfarshire), but it was not until 1882 that B. N. Peach recognized the affinities of this animal to millipedes and named the species K. forfarensis. Peach named another Silurian species, K. obanensis, from Old Red Sandstone deposits from the Scottish island of Kerrera in 1899; John Almond questioned the affinity of this species to Kampecaris in 1985, for several reasons including the presence of 14 segments behind the head. In 1951, B. B. Clarke described a Devonian species, K. dinmorensis, from Dinmore Hill, Herefordshire, England. Another Devonian species, K. tuberculata, was subsequently recognized as being closer to flat-backed millipedes in the group Archipolypoda, and renamed to Palaeodesmus.

Archidesmus is an extinct millipede genus from the Lower Devonian Old Red Sandstone of the United Kingdom. It is the only member of the taxonomic family Archidesmidae. Individuals were up to 5 cm (2.0 in) long, and had 60 to 80 body segments decorated with tubercles (bumps) on the upper surface, and most segments possessed wing-like keels (paranota) extending to the side. The type species Archidesmus macnicoli was described by British paleontologist Benjamin Peach in 1882. A second species, A. loganensis was also described by Peach but its status as a valid species- or even a myriapod- is debated.