Reproduction  by  Alex Crain

The mating season for the millipede H. haydeniana occurs in the spring. During the mating season the male and female millipede come towards each other head on, where they meet and then raise their anterior ends.  Next they climb up each other’s ventral side and a female millipede receives sperm from the male, which is stored in the seminal receptacles located in the vulvae. (Blower 1985) Both the female and the male’s reproductive openings are located on the third body segment, just behind the second pair of legs. The female’s is surrounded by two different plates, one of which covers the opening. (Branson 1997) The H. haydeniana male does what is called direct sperm transfer, where the sperm is placed directly into the female opening. This transfer is made possible through the use of special intromittent organs known as gonopods. (Blower 1985)

. yellow spotted millipede

Figure 1. two H. haydeniana during mating season

All millipedes are oviparous, which means that they lay eggs. The most common place for a H. haydeniana millipede to lay her eggs is under a rotten log. There have been some cases among millipedes where the male millipede participates in the act of egg-guarding, standing guard while the eggs are developing. (Requena et al. 2009). Millipedes lay somewhere between 30 and 300 eggs each breeding season. The young hatch after three or more weeks of incubation, sometime during the late spring. (Branson 1997) Reproducing can be quite taxing on the female, according to a study done at the Kansas Academy of Science. It was shown that in some species the more often a female reproduces the shorter her life span. Individual females collected in April mated about 5 times each compared to individuals who were collected in March, who only mated an average of 1.75 each. April individuals lived about a month, whereas March individuals lived over 4. ( Youngsteadt 2009)

 fallen log

Figure 2. A fallen log as an ideal spot for a female to lay her eggs

The eggs then hatch into an immobile pupoid, which then molts into an instar. At the instar stage, the millipede has four developed rings (segments) and three pairs of legs between the rings. Behind the mobile rings are two to three immobile rings which are then followed by the telson or posterior-most segment of the body, like a tail. By the next molt the immobile rings will all have pairs of legs. (Blower 1985)

millipede anterior anatomy

Figure 3. The general anterior anatomy of a millipede

Within millipedes there are three types of anamorphosis or a change to a higher form. The first type being euanamorphosis, where each molt is accompanied by the addition of a new ring, even after the millipede has reached sexual maturity. The second type is called teloanamorphosis, where the addition of rings stops at a certain stage and the molting stops. Finally the third type is known as hemianamorphosis where the addition of new rings continues until a certain stage, however molting continues. (Blower et al. 1993) H. haydeniana exhibits the second type of anamorphosis or teloanamorphosis, their molting stops after they have reached sexual maturity. (Blower 1985) 

References in Order of Appearance:

Blower, J.G. 1985. Millipedes: Keys and Notes for the Identification of the Especies. The Bath Press, Avon, UK.

Branson, B. A. 1997. Legions of legs. World & I 12: 170.

Requena, S.R. et al. 2009. Efficiency of uniparental male and female care against egg predators in two closely related syntopic harvestmen. Animal Behavior 78:1169-1176


Youngsteadt, N.W. 2009. Laboratory Observations on the Natural History of Pseudopolydesmus pinetorum (Diplopoda, Poydesmida, Polydesmidae) with Emphasis on Reproduction and Growth. Transactions of the Kansas Academy of Science 112: 67-76.

 Blower, J.G., Dohle W. and Enghoff H. 1993. Anamorphosis in millipedes (Diplopoda)- the present state of knowledge with some developmental and phylogenetic considerations. Zoological Journal of the Linnean Society 109: 103-234

Photos References in Order of Appearance:

Wikimedia Commons 2011.<> Accessed 6 December 2013.

Wikimedia Commons 2009.<> Accessed 6 December 2013.

Wikimedia Commons 2013.<> Accessed 6 December 2013.