Polydesmida

Polydesmida (from the Greek poly "many" and desmos "bond") is the largest order of millipedes, with more than 5,000 species, including all the millipedes reported to produce hydrogen cyanide (HCN). This order is also the most diverse of the millipede orders in terms of morphology. Millipedes in this order are found in all regions of the world other than Antarctica.

Polydesmida (from the Greek poly "many" and desmos "bond") is the largest order of millipedes, with more than 5,000 species, including all the millipedes reported to produce hydrogen cyanide (HCN). This order is also the most diverse of the millipede orders in terms of morphology. Millipedes in this order are found in all regions of the world other than Antarctica.

Description

Members of the order Polydesmida are also known as flat-backed millipedes, because on most species, each body segment has wide lateral keels known as paranota. These keels are produced by the posterior half (metazonite) of each body ring behind the collum. Polydesmids have no eyes, and vary in length from 1.4 to 134 mm. Many of the larger species show bright coloration patterns which warn predators of their toxic secretions. Adults usually have 20 segments, counting the collum as the first ring and the telson as the last ring. Juveniles have from 7 to 19 rings. In species with the usual 20 segments, adult females have 31 pairs of legs, but in adult males, the eighth leg pair (the first leg pair of the 7th ring) is modified into a single pair of gonopods, leaving only 30 pairs of walking legs.

Ecology

Polydesmids are very common in leaf litter, where they burrow by levering with the anterior end of the body. These millipedes feed on decaying vegetation. Some species are prey for funnel-web spiders.

References

External links

LucidCentral:Polydesmida External Anatomy of Polydesmida North American Polydesmida - BugGuide

Text derived from https://en.wikipedia.org/w/index.php?oldid=1354739055 under CC BY-SA 4.0; modifications have been made.