flat-backed millipedes

(order Polydesmida)

Overview  •  Description  •  Distribution  •  Taxonomy

Overview

Polydesmida (flat-backed millipedes) is the largest order of millipedes. It occurs on every continent worldwide except Antarctica and Greenland. There are about 3,500 species that have been described and more than that yet to be described. They are found in almost all habitats in leaf litter, under the bark of rotting logs, under rocks, and on living trees. They feed on decaying vegetation or the leaves and shoots of live plants. When threatened they exude irritants from pores along the sides of their body.
 
flat-backed millipede (order Polydesmida)
 
 
Description

Flat-backed millipedes are named for flattened, wing-like extensions (paranota) on the sides of each body segment on most species. Many also appear flattened when viewed from the side. However, some are cylindrical and have reduced paranota or no paranota. All are blind and lack eyes. Mature adults are ⅛″ to 5″ (3 to 130 mm) long. They have 19 or 20 body rings. There is no dorsal groove. On the male, the front pair of legs on the seventh ring are modified as reproductive structures (gonopods), while the hind pair are normal walking legs.

Distribution

Distribution Map

  

Sources

7, 29, 30, 82.
6/20/2025    
     

Occurrence

 
Taxonomy

Subphylum

Myriapoda (myriapods)

Class

Diplopoda (millipedes)

Subclass

Chilognatha

Infraclass

Helminthomorpha (worm-like millipedes)

Subterclass

Eugnatha

Superorder

Merocheta
   

Subordinate Taxa

Suborder Dalodesmidea

Suborder Leptodesmidea

Suborder Paradoxosomatidea (provisionally accepted suborder)

Suborder Polydesmidea

Suborder Strongylosomatidea

   

Synonyms

 
   

Common Names

flat-backed millipedes

 

 

 

 

 

 

 

 

 

 

 

 

 

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MinnesotaSeasons.com Photos

Flat-backed millipede on cowpie
flat-backed millipede (order Polydesmida)   flat-backed millipede (order Polydesmida)
     
flat-backed millipede (order Polydesmida)    

 

Camera

 

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slideshow

 

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Other Videos

Polydesmida
Paul Mosquera
About

May 8, 2016

 

Camcorder

 

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MinnesotaSeasons.com Sightings

Northern Tallgrass Prairie NWR, Rengstorf Unit

 

 

Binoculars

 

Created: 9/26/2020

Last Updated:

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