That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information

Among the world’s 10,000 or so millipede species we find a number of common as well as extremely specialized creatures, many of which make interesting terrarium subjects. The commonly available giant African millipede (Achispirospreptus gigas) is, at nearly 11 inches long, a very impressive beast that may reach 10 years of age and reproduce in captivity.  A number of other species appear in the trade from time to time as well…while the largest hail from the tropics, several millipedes native to the USA, such as Narceus americanus, are also quite large, and some are brilliantly colored.

The following information applies mainly to the African giant millipede, but also holds true for many of the other large African and Southeast Asian species that enter the trade.

A Simple but Effective Feeding Technique

Judging from the questions I’ve received from millipede enthusiasts over the years, a poor diet is the main reason that these creatures sometimes fail to thrive in captivity.

One trick that I have found particularly useful is to add a handful of a reptile calcium supplement, such as Reptocal to the substrate in a millipede terrarium.  Millipedes consume a good deal of leaf litter and, in some cases, rotting wood, and will ingest calcium mixed into the litter as well.  They seem to require quite a bit of calcium, especially when molting and forming a new exoskeleton, so I powder their other food with it also.

Leaf Litter and Wood

In order to provide as much dietary variety as possible, I always keep millipedes in a substrate comprised of at least 50% leaf litter (oak, ash and other native species) and well-rotted (soft and crumbly) wood collected locally.  This is replaced periodically as the millipedes tunnel through and consume the nutrients therein.

The balance of the substrate consists of coconut husk  and top soil.  Millipedes need to burrow, especially when laying eggs and molting, so keep at least 4-6 inches of substrate available to them.  A layer of gravel at the terrarium’s bottom will assist in drainage.

Dietary Variety

As we know little about the actual nutritional needs of any millipedes, I strive to provide as much variety as possible.  This seems a useful technique, as I’ve been able to breed several tropical and native species over the years, and have kept individual millipedes for over a decade.  Please check out Part II of this article for salad recipes and other foods that have served me well over the years when keeping millipedes.

Further Reading

Please see my article Millipede Emergency for a unique twist to millipede keeping.

Having been chased by a Kodiak bear, confronted by an escaped king cobra and otherwise molested by scores of formidable animals, I felt relatively secure in accepting responsibility for a group of arboreal South American millipedes entrusted to me by colleague about to travel abroad. A primatologist, she had observed capuchin monkeys to rub millipedes over their bodies, and was investigating the situation (I, on the other hand, have always been far more interested in millipedes than monkeys!).

Deadly Millipedes?

A week after her departure, another coworker phoned me at 4 AM, frantically speaking in the rapid fire Spanish typical of her native Venezuela…and which I have great difficulty in grasping at 4 PM, much less 4 AM! Eventually I learned that 3 elderly millipede researchers had passed away recently, and that preliminary evidence indicated that cyanide poisoning, courtesy of the millipedes’ defensive chemicals, was suspected. I was warned against handling the millipedes (which I had been doing for weeks!) or putting them near my face (which I do not do with any creature).

The deaths turned out to be coincidental and unrelated to millipedes, but the incident led to a good deal of research into the defensive chemicals produced by these popular terrarium pets. It seems that millipede toxins are a very unique and complicated group of compounds.

Exploiting Millipede Toxins

Interestingly, a number of species of frogs and monkeys harness these chemical weapons for their own use. Although lagging behind such creatures by a few million years, humans are also getting into the act, and we may soon be putting millipede secretions to medicinal use.

An Amazing Coincidence!!!

The incident I related above, concerning myself and the millipedes, transpired approximately 8-10 years ago. I’m not sure why I decided to write about it today, but I’ve had millipede articles on my mind for some time, and thought this would make a nice introduction to the topic.

After writing this article I searched for a reference to add, for those readers who wished to learn more. You can imagine my shock when I discovered that today’s NY Times (28 June 2009) carries an article about the very same monkeys, people and millipedes involved in my story!!!

To read the entire article, please go to http://www.nytimes.com/2000/12/05/science/05MONK.html?pagewanted=print.

Next time I’ll explore the nature of these defensive weapons and the uses that monkeys, frogs and people are finding for them. Following that we’ll take a look at keeping and breeding millipedes in captivity.

Image referenced from Wikipedia and originally posted by Prashanthns.

Note: Please see Part I and Part 2 for further information on the captive care and natural history of this insect.

Social Grouping

The orange-spotted roach is sexually dimorphic – males have full wings (but rarely if ever fly), while females have only wing-stubs.  A ratio of 1 male per 3-5 females is ideal…excess males should be preferentially used as food for your collection.  Maintaining the roaches at this ratio will provide for a great deal of social interaction (please see Part I, Captive Habitat) and increased reproduction.

Males attempt to bluff intruders onto their territories by rising up on their legs and fluttering the wings.  If this fails, a shoving match will ensue, with the loser retreating intact (well, except for his pride!).

Captive Longevity

The life cycle is 18 months to 2 years…but this is not well documented.  Please keep notes and pass along anything new you might learn.

Reproduction

Fertilization is internal, via a sperm packet deposited by the male.  Females produce the typical roach oothecum, or egg case, but retain it internally for a gestation period of approximately 1 month.

The young, 20-30 in number, are born alive and reach sexual maturity in 3-4 months (this varies with temperature and stocking levels).

Miscellaneous

The reduced wing size in female orange-spotted roaches (and similar species) is attributed to paedomorphosis, or the retention of juvenile characteristics, rather than to wing growth inhibition.

Flight muscle is, metabolically, one of the most active of animal tissues, and very “expensive” to support.  It is theorized that the resources put into maintaining the flight muscles may, in roaches, take away from reproductive potential.  In other words, female roaches are, in essence, “trading” flight for the ability to produce additional eggs.  Males of some species are though to retain the power of flight so as to be able to cover more ground when searching for mates.

A description of the journal Cockroach Studies, along with photos of long-winged and wingless species, is posted at:

http://www.nhm.ac.uk/about-us/news/2006/may/news_8129.html

Image referenced from Wikipedia, here.

Note:  Please see my article Product Review: Gel Based Water Sources for House Crickets for additional information on cricket-keeping.

According to studies carried out at the Bronx Zoo, house crickets, Acheta domestica, should be allowed to feed for at least 48 hours before themselves being offered to captive reptiles and amphibians as a dietary item.  This time period allows the crickets to absorb nutrients that will, ideally, offset their naturally poor ratio of calcium to phosphorus (which should, in most situations, be 2:1).

Feeding Crickets

Chick laying mash, trout chow and baby cereal can all be fed to crickets, but none are formulated specifically for these insects, and each has disadvantages.  When feeding crickets in public collections or at home, I now rely exclusively upon commercial cricket foods.  The following products are all very well-accepted by these perpetually hungry little beasts, and the nutritional profiles of the diets (including calcium content) are based on the latest available research:

Ziegler Monster High Calcium Cricket Food

Orange Cube Cricket Food

R-Zilla Gutload Cricket Supplement

Dietary Supplements

As has always been my practice, I add a bit of Tetra-Min Flake Fish Food to the commercial cricket foods.  Both are consumed ravenously, and the wide variety of ingredients in the flakes helps assure that the crickets are receiving a healthful diet.

In addition, I add to their diets the powdery residue left at the bottom of oatmeal, wheat germ, nut and whole grain cereal containers.  Oranges, yams, kale, carrots and other fruits and vegetables should also be provided on occasion, but only in amounts that are consumed quickly, lest mold develop.

Click: The Orange Spotted Roach: an Interesting Pet and Valuable Food for Reptiles, Amphibians, Invertebrates, Birds and Fishes – Part 1, to read the first part of this article.

Substrate

When keeping large colonies as a food source for other animals, the roaches should be well-supplied with cardboard egg crate, paper towel/toilet paper rolls or crumpled sheets of cardboard upon which to climb.  The bottom of the enclosure should be kept bare…substrate will complicate cleaning, encourage mold and make it difficult to locate small roaches.

At cleaning time, the cardboard, to which most of the roaches will cling, can be removed while the enclosure is washed (use hot water and bleach or table salt) and dried.  The cardboard should be replaced from time to time as well.

Fecal material from the bottom of the enclosure, and old cardboard, should be frozen before being discarded to prevent un-noticed nymphs from establishing feral colonies.

If you are keeping smaller numbers of roaches as pets, you may wish to set up a naturalistic terrarium.  R Zilla Alfalfa Bedding or Coconut Husk may be used as a substrate.  Stock your terrarium with rocks, driftwood, and plastic reptile shelters…males will establish territories around and under such structures.  In such a set-up you should be able to observe them competing for females (see below), and will be privy to other interesting behaviors not easily seen in a crowded colony situation.

Be sure to remove nymphs from time to time, as territoriality seems to break down under crowded conditions, and there will consequently then be less for you to observe.

Treated in this manner, as you might any other unusual pet, orange-spotted roaches will provide you with many surprises.  We still have a great deal to learn about these insects…observant keepers stand a good chance of learning something new.

Water

I use R-Zilla Cricket Calcium Drink Supplement as the sole water source for all roach species.  This and similar gel-based products eliminates the need for providing fruit as a water source, which can mold and cause health problems (a small amount of fruit added to the diet is a good idea) and supplies additional calcium to the insects.

Feeding

Jurassi-Diet or R-Zilla Cricket Food should be used as the basis of the diet.  Both are readily accepted, and help to improve the roaches’ calcium: phosphorous ratio (in the event they are to be used as pet food).

Orange spotted roaches accept a wide variety of foods…but this should not trick us into thinking that they can survive on whatever is at hand.  They should be provided a balanced diet, both for their health and that of the animals to which they may be fed.

To the basic diet of commercial cricket food I always add tropical fish food flakes (I have found such to be useful with all roach species, crickets, millipedes and many other invertebrates), powdered baby food, and a bit of wheat germ. They should also be fed fruits and vegetables once or twice weekly.

An interesting article on cockroach diversity and evolution (London Museum of Natural History) is posted at:

http://blattodea-culture-group.org/content/cockroaches-amazing-diversity

Image referenced from Wikipedia Commons, here.