Habitat and Geography by  S u n i t a  N a n d i h a l l i

H. haydeniana is found to live in the Pacific Northwest region of the United States. This includes Oregon, Washington, northern California, and Vancouver Island. The type locality (or the area where this species was first identified) of H. haydeniana was Oregon, U.S.A. (Chamberlin & Hoffman 1958).

Pacific Northwest
Figure 1. Organisms like H. haydeniana are found in the Pacific Northwest region of North America.

Since millipedes feed on dead plant material and fragments of organic matter (Hopkin & Reed 1992) litter layer in mature conifer forests with Douglas-fir is H. haydeniana’s habitat of choice. (Acorn & Sheldon 2001). Adults are found in the upper layer, immature stages deeper in the litter. However, the leaf litter in the Pacific Northwest consists of a lot more than just pine trees. Ash, Sycamore, Aspen, Birch, Cedar, Cherry, Chestnut, Cypress, Dogwood, Fir, Elm, Oak, Maple, Spruce, and Redwood are just a few more common trees that grow in this area and that H. haydeniana has fed on as well. (Jensen et al.  2011).   

It has been shown in numerous cases that millipedes are better for plant growth and, in turn, ecosystems altogether, than even worms. This is because H. haydeniana excretes decomposed organic matter in the form of fecal pellets. (Thakur et al. 2011).  It was found that higher values of Nitrogen, Phosphorous, Potassium, Magnesium, and Calcium (necessary nutrients in order for plants to produce enzymes and nucleic acids) were observed in millipede compost as opposed to worm compost or ordinary soil. Since millipede feces are so high in nutrients, it is not uncommon for them to partake in coprophagy or the eating of one’s own feces in order to gain extra nutrients that you previously didn’t during the first full cycle of digestion.

Although the chemical defenses of H. haydeniana are able to keep most predators at bay, one specific beetle is specialized in consuming H. haydeniana. P. laevissimus also lives in California, Oregon, and Washington and feeds on millipedes like H. haydeniana. (Denton 1997).

Some other organisms that live in the Pacific Northwest Region of the United States include T. longiglossus, D. maculata, H. thysbe, C. felis, and V. vinifera.

Figure 2. The Bald-faced hornet, D. maculata, is another arthropod that lives in the Pacific Northwest

References in Order of Appearance:

Chamberlin, R.V. and Hoffman, R.L. 1958. Checklist of the millipedes of North America. United States Government Printing Office, Washington, D.C., U.S.A.

Hopkin, S.P. and Read, H.J. 1992. The biology of millipedes. Oxford University Press, New York, U.S.A.

Acorn, J. and Sheldon, I. 2001. Bugs of Washington and Oregon. Lone Pine Publishing, Edmonton, Canada.

Jensen, E., Zahler, D., Patterson, B., & Littlefield, B. 2011. Common trees of the pacific northwest. Oregon State University. <URL: http://oregonstate.edu/trees/name_common.html> Accessed 9 November 2013.

Thakur, P.C.,  Apurva, P., and Sinha, S.K. 2011. Comparative study of characteristics of biocompost produced by millipedes and earthworms. Advances in Applied Science Research 2: 94-98.

Denton, M. 1997. Promecognathus laevissimus dejean 1829. The Evergreen State College. <URL: http://academic.evergreen.edu/projects/evergreenBiota/kingdom/animalia/phylum/arthropoda/class/insecta/order/coleoptera/family/carabidae/
GENERA/PROMECOGNATHUS/P_laevissimus.HTM > Accessed 9 November 2013.

Photo References in Order of Appearance:

Wikimedia Commons 2012. <http://commons.wikimedia.org/wiki/File:Pacific_northwest-relief.png> Accessed 19 November 2013.

Wikimedia Commons 2012. <http://commons.wikimedia.org/wiki/File:July_31,_2012_-_Bald-faced_Hornet_on_Red_Flower.jpg> Accessed 5 December 2013.