Lots of legs

  yellow spotted millipede 

In my duckling days, fearsome centipedes longer than my duck were periodic threats that lurked beneath kitchen sinks and stones in the garden. Such multi-legged menaces are rare in high-rise Singapore but keen-eyed strollers can see loose platoons of black and yellow polydesmid millipedes (right) on neighbourhood sidewalks and the damp floors of wet markets every morning. Legions are stomped by passing feet, while heat and dessication consumes those unable to reach the shelter of cool earth. Also known as plated millipedes, polydesmids have fender-like expansions on their segments that in some species result in a prehistoric appearance. Somewhat less common but still a feature on parched pavements is the slow-moving red legged millipede (Trigoniulus lumbricinus) with its cylindrical body. When disturbed, both species may roll themselves up into diplopodic balls that simply result in brown round stains on the grey ground.

  millipede 

Members of the class Myriapoda, millipedes, centipedes and their allies make up a relatively small segment of the mighty phylum Arthropoda. Apart from the millipedes and centipedes, the group also includes two little-known subclasses: Pauropoda (500+ species) and Symphyla (175 species). Pauropods are minute (0.5-1.5 mm) inhabitants of moist soil and leaf litter, while symphylans (<1 cm) are tiny centipede-like creatures with long antennae. At the upper end of the scale are the giant Scolopendra centipedes that reach a foot long and deliver ferocious bites that cause great pain and fever. The largest species lives in South America but slightly smaller Scolopendrids can be found across Southeast Asia.

  millipede red 

The biggest millipede is Graphidostreptus gigas, an African species that grows to 11 inches. In Singapore, visitors to the nature reserves might spot a robust local species that gets to 8 inches. My duck found the specimen above on a tree trunk just above eye level where it appeared rather bothered and bewildered. Some millipedes exude toxic secretions to deter predators but Diplopods are by and large innocuous animals that like nothing better than to muck around in humus and bark in search of organic matter and fungi. No millipede is known to have a thousand legs though; the record holder is a 33 mm worm-like thing known only from a 0.8 square km reserve in California.

  millipede segments 

  millipede head with mites 

Some centipedes, especially the unhappily-named house centipedes (Scutigeridae), have legs that are undeniably icky and can reach hair-raising speeds of 40 cm per second. Most millipedes are slowpokes and although a few (such as the reddish specimen above – also found on a tree trunk) may look somewhat like centipedes, they are easily distinguished by their diplosegmentation. Essentially, this means that adjacent body somite, each bearing a pair of appendages, are fused into a segment with four legs. On this specimen, the segments look like the little threaded beadlets worn by fashionable lasses. In North America, a genus of bioluminescent millipedes produces a continuous neon-white glow that has been described as "resembling the starry sky on a dark night." Less appealing though are instances of parasitism, such as the little red mites that cling to this other specimen (also on a tree trunk – haven't they read the literature?), presumably enjoying a free ride on a juicy carriage. Or maybe it's trying to start a new trend of lugging live head accessories...

Non-online sources:
George C. McGavin, Insects, Spiders and other Terrestrial Arthropods. Dorling Kindersley 2000.
Colin Tudge, The Variety of Life. Oxford University Press 2000.
D.S. Hill et al, Insects of Hong Kong. Hong Kong University Press 1982.
A Guide to Urban Creatures. Singapore Science Centre 2002.

Comments

[Sarah]

Hi

Do you have any pictures of Graphidostreptus gigas?
We are trying to track some down for a big bugs book.

Thanks
Sarah