Class Diplopoda - Millipedes
Classification Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Myriapoda (Myriapods)
Class Diplopoda (Millipedes)
Other Common Names Millipeds Explanation of Names Diplopoda Blainville in Gervais 1844
'double-legged'
Numbers worldwide, >13,200 spp., 80,000 estimated (based on known degrees of endemism), arranged in 2 subclasses, 18 orders, and ~200 families (1); in our area, >900 described spp. in 217 genera of 52 families (of which 17 are endemic to NA, and 7 are non-native) but hundreds await description, particularly in the Glomeridae, Parajulidae, Atopetholidae, Cleidogonidae, Trichopetalidae, Striariidae, Polydesmidae, and Nearctodesmidae (2)(3)(4); 66 documented & ~100 estimated spp. in Canada (5)
Families represented in our area
Classification adapted from (3). Taxa not yet in the guide are marked (*), non-native taxa in brackets.
CLASS DIPLOPODA
Size 3‒320+ mm worldwide; the longest millipede of our fauna (Paeromopus paniculus) up to 160 mm Identification key to orders & families in (6)(7)
Two pairs of legs on all but the first three body segments (47‒375 leg pairs and 25‒189 body segments, not counting head and tail segment). Body flattened or cylindrical. In some groups, notably Polydesmida, body segments are laterally explanate. Pill Millipedes (Glomerida) are short-bodied, can roll into a ball, and look like pillbugs.
Sexing: adult males usually have modified legs ( gonopods). Most have 1‒2 pairs of gonopods on segment 7, but in the Glomerida they are on posterior segments, while Polyxenida lack gonopods altogether. Range worldwide and throughout NA Habitat Moist habitats under rocks, rotting logs, organic debris, etc. Food usually decaying plant material; a few spp. occasionally carnivorous. Some may feed on living plant tissue. Life Cycle Millipedes hatch with 3 pairs of legs, and add segments/legs as they molt; some live up to 7 years.
Remarks To protect themselves, millipedes coil or roll into a ball; many emit poisonous (e.g., cyanide-containing) or foul substances (e.g., benzoquinones) (8)
"Millipedes lack the structures to bite, pinch, or sting, and are harmless to humans, although the defensive secretions burn if they get into the eyes. Millipedes are non-toxic to humans and can be picked up by hand. Some secretions discolor the skin, with no lasting effects. Some large, cylindrical, tropical species squirt defensive secretions up to a half meter and can blind chickens and dogs." ‒Rowland Shelley See Also Centipedes have only one pair of legs per body segment, and the last pair of legs extends backwards behind the body; they can run fast and can bite. Millipedes are slow-moving and unable to bite. (9) Works Cited | 2. | Checklist of the millipeds of North and Middle America
Richard L. Hoffman. 1999. Virginia Museum of Natural History Special Publications. | |
| 5. | Myriapoda of Canada
Langor D.W., deWaard J.R., Snyder B.A. 2019. ZooKeys 819: 169-186. | |
| 9. | Spiders and Their Kin: A Golden Guide from St. Martin's Press
Herbert W. Levi, Lorna R. Levi, Nicholas Strekalovsky. 2001. St. Martin's Press. |  |
Contributed by Troy Bartlett on 16 February, 2004 - 12:32pm Additional contributions by Beatriz Moisset, Robin McLeod, Lynette Elliott, Christopher C Wirth, Chuck Entz, Mike Quinn, v belov, KenW, DerekHennen, Marci Hess, biosam, JBrown, Arturo SantosLast updated 8 December, 2023 - 8:47am |
