Myriapoda (from Ancient Greek μυρίος (muríos) ‘ten thousand’, and πούς (poús) ‘foot’) is a subphylum of arthropods containing millipedes, centipedes, and their relatives; have many body segments, each segment bearing one or two pairs of legs (or in a few cases being legless). They are sometimes grouped with the hexapods.
Myriapods have in common a body structure characterized by the presence of a cephalic capsule (similar to that of hexapods in the number and arrangement of segments, and in the type of appendages) and an elongated trunk with numerous segments, each bearing a pair of legs (in the case of centipedes and two pairs in the case of millipedes). The different classes that make up this subphylum have significant differences, in fact some authors do not consider it a valid systematic grouping.
|Superclass||Myriapoda (Latreille, 1802)|
- Chilopoda (centipede)
- Diplopoda (millipede)
Fossil remains of myriapods date back to the Silurian (about 400 million years ago), but some molecular analyses suggest that this group of arthropods may have differentiated as early as the Cambrian (about 500 million years ago). Also from this period is a multi-segmented centipede-like animal called Xanthomyria spinosa, which may represent the oldest fossil record of a myriapod. Other myriapod-like organisms (Pseudoiulia cambriensis) have been found in even older strata (Lower Cambrian, 520 million years ago). During the Carboniferous (about 300 million years ago) myriapods developed enormously (Acantherpestes, Euphoberia) and even gave rise to giant forms over two meters long (Arthropleura), due to the high density of oxygen in the atmosphere.
The millipede Illacme plenipes is considered the myriapod with the most pairs of legs, in fact it has 750, the females longer than males reach 300 mm in length. These specimens live in California and were first found in 1926.
In August 2020 was discovered in Australia at a depth of sixty meters, the first millipede to have 1306 legs that is 653 pairs of limbs, 330 segments, a diameter of 0.95 millimeters and a length of 95.7 millimeters, this myriapod was named Eumillipes Persephone.