Aotearoa New Zealand has plenty of giant animals. Giant parrots, snails, eagles, moa – and there are more out there lurking in the undergrowth. One of those is the giant centipede (Cormocephalus rubriceps).
Some sources say these many-legged giants grow to 16cm in length. Other sources say a whopping 25cm. However, sadly (or gladly?), you’re unlikely to see a full-sized centipede in all its gargantuan glory.
Pressures from predators
Although they are predators themselves, birds, rats and hedgehogs prey on centipedes.
Because of rat predation, full-sized individuals are now found only on rat-free islands, as mainland centipedes fall victim to predators before they reach their maximum size.
They are most abundant on predator free islands off the coast of the North Island, such as the Three Kings Islands. On an entomology expedition in 1970, researchers were so bothered by nighttime centipede visits that they spread tinfoil around their sleeping bags. Rattling feet on the foil alerted them to the arrival of the giant critters.
Big and bitey
Known as hara or hura to Māori, the giant centipede shelters under or in logs and amongst leaves on the ground, and it’s carnivorous, crushing and piercing prey with its fearsome jaws, or mandibles.
Its bite probably won’t do any lasting harm to humans, but it really hurts.
The centipede’s venom claws are an impressive and unique feature of centipedes. These large, robust, pincer-like appendages – known as forcipules are located on the first segment following the head and are actually modified legs, which function as jaws. They are jointed, open and close in a horizontal plane and end in sharp claws.
Centipedes use their forcipules to capture and inject venom into their prey. The ducts of venom glands open near the tips of the claws. The forcipules occur in all centipedes but not in any other arthropods.
A centipede doesn’t have 100 legs
Despite their name, no centipede species has exactly 100 legs. Oddly, in most cases, females have more legs than males.
New Zealand’s giant centipede belongs to the Scolopendromorpha order. Most of them, especially the soil dwellers, are much smaller and don’t get any bigger than 5 cm. One thing common to all Scolopendromorpha is that they always have twenty-one pairs of legs, which are all different lengths.
Behind the head, the body consists of 15 or more segments, each bearing a single pair of legs. Each pair of legs is slightly longer than the one in front of it, ensuring they don’t overlap and reducing the chance they will collide while moving swiftly. In extreme cases, the last pair of legs may be twice as long as the first pair.
Centipedes can regenerate lost appendages – the regenerating appendage slowly develops with each subsequent moult, although a perfect appendage is regenerated only if the injury had occurred at an early stage in development; otherwise the regenerated appendage is deformed and stunted.
Built for life in the dark and wet
Worldwide, 8,000 different species of centipedes are thought to exist, of which 3,000 have been described. New Zealand’s centipede fauna is distinctly southern (Gondwanan) and includes at least 35 species. Several genera are endemic – found only in Aotearoa.
They occur in a variety of habitats, but all share one key requirement: a moist microhabitat. Centipedes lack the waxy cuticle of insects and spiders. This means they lose water quickly, so centipedes live in soil and leaf litter, under stones and dead wood, and inside logs.
Centipedes are among the largest land invertebrate predators, but they are often blind. Many centipede species lack eyes completely, but some have a variable number of ocelli, which are sometimes clustered to form true compound eyes. However, these eyes can only discern light and dark and have no true vision.
In some species, the first pair of legs at the head end of the centipede acts as sense organs similar to antennae, but unlike the antennae of most other animals, the centipede’s point backwards.
Mum guards her babies
Female giant centipedes are caring mothers. The female lays an egg mass in a cavity excavated in the soil. She stays in the cavity, coiled around the eggs, until they hatch. The newborn centipedes resemble miniature adults and have the adult number of legs, although the reproductive parts are not developed. Growth and development are through a series of moults.
Each stage of development lasts for several months, and in cold climates a centipede can take 2-3 years to reach maturity. Adult centipedes continue to moult, further increasing in size. Many die after their first breeding season, but many continue to live and moult for several more years.
Not all New Zealand’s centipedes belong to the Scolopendromorpha order.
The New Zealand Craterostigmus is a medium-sized (up to 5 cm), greenish-brown centipede, with a large, elongate, red-brown head. The forcipules are massive and clearly visible from above, framing the head.
Craterostigmus occurs in forest habitats on the South Island, where it is quite common, but little is known about this centipede’s biology in New Zealand.
So who knows what fascinating centipede weirdness is yet to be discovered…
