SCIBERRAS, A. (2013) Fauna regarded as domestic pests in the Maltese islands - The Myriapods

The Myriapods

By Arnold Sciberras

As someone at home steps on a creature that instantly releases a foul smell, that present organism defiantly belongs to this group on which the article is about. Myriapoda is a group (subphylum) of arthropods( which also includes insects, arachnids and crustaceans) containing millipedes, centipedes, and others. The group has 13,000 species known, all of which are terrestrial (land dwellers). Although their name suggests they have myriad (10,000) legs, Myriapods range from having over 750 in some species to others having fewer than ten legs.

Myriapods have a single pair of antennae and, in most cases, simple eyes. The mouthparts lie on the underside of the head. A pair of mandibles lie inside the mouth. Myriapods breathe through spiracles (holes on the exterior that let air in) that connect to a tracheal system similar to that of insects. There is a long tubular heart that extends through much of the body, but usually few, if any, blood vessels.

During mating, male myriapods produce a packet of sperm, or spermatophore, which they must transfer to the female externally; this process is often complex and highly developed. The female lays eggs which hatch as much shortened versions of the adults, with only a few segments and as few as three pairs of legs. The young add additional segments and limbs as they repeatedly moult to reach the adult form.

Myriapods are most abundant in moist locations, where they fulfill an important role in breaking down decaying plant material, although a few live in grasslands, semi-arid habitats or even deserts. Most species like millipieds eat plant or decaying matter, with the exception of centipedes, which are chiefly nocturnal predators. Pauropodans and symphylans are small, sometimes microscopic animals that resemble centipedes superficially and live in soils. Millipedes differ from the other groups in having their body segments fused into pairs, giving the appearance that each segment bears two pairs of legs, while the other three groups have a single pair of legs on each body segment. Although not generally considered dangerous to humans, many myriapods produce noxious secretions which can cause temporary blistering and discolouration of the skin.

Centipedes make up the order Chilopoda. They are fast, predatory and venomous, hunting mostly at night. There are around 3,300 species .they can range from species not exceeding 12 mm to others which may exceed 30 cm. About 16 species have been recorded from the Maltese islands.. Common encounters can be with the following 3 species:

The Soil Centipede Himantharium gabrielis Xini Tal-Hamrija is quite a docile species and is restricted to soil environments. It is easily found in gardens and under pots. Very beneficial in controlling a number pest species.

The Yellow Banded Centipede Scolopendra cingulata Xini Isfar is one of the smallest members of the scolopendra family at approximately 10-15 cm. They are easily recognized by the alternating bands of black and yellow/gold.

The head of this centipede has a pair of antennae, jaw-like mandibles, and other mouth parts. Each segment has one pair of legs. The front segment has a pair of venomous claws (called maxillipedes) that are used for both defense and for capturing and paralyzing prey. The venom is less toxic than other scolopendrid centipedes, but still quite painful. they are still fast moving and can be aggressive so it's best just to look at these colorful creatures rather than try to handle them.They are mostly nocturnal and opportunistic carnivorous hunters, feeding on a broad variety of ground dwelling insects. Youngsters will eat crickets, or other small insects. Adults will consume almost any creature that is not larger that itself, including large crickets, other large insects, and even small lizards. Prefers out door environments but can be met with in urban areas .it is very beneficial in controlling pest species of other arthropods.

The House Centipide Scutigera coleoptrata Xini Ta`l-Indewwa is unfortunately a well considered pest locally. Originally endemic to the Mediterranean region, the species has spread to other parts of the world, where it usually lives in human homes. This species can live its entire life inside a building, usually the ground levels of homes. They are generally considered harmless to humans. Bites are not common, and the jaws of most house centipedes are not strong enough to penetrate human skin . the latter feed on spiders, bedbugs, termites, cockroaches, silverfish, ants, and other household arthropods. They administer venom through modified legs. These are not part of their mandibles, so strictly speaking they sting rather than bite. They are mostly nocturnal hunters. Despite their developed eyes they seem to rely mostly on their antennae when hunting. Their antennae are sensitive to both smells and tactile information. They use both their mandibles and their legs for holding prey. This way they can deal with several small insects at the same time. They avoid dangerous insects. They also adapted their feeding pattern to the hazard the prey might pose to them. For wasps, they retreat after applying the venom to give it time to take effect. When the centipede is in danger of becoming prey itself, it can detach any legs that have become trapped. They live anywhere from three to seven years, depending on the environment. They can start breeding in their third year. For mating the male and female circle around each other. They initiate contact with their antennae. The male deposits his sperm on the ground and the female then uses it to fertilize her eggs. Some report that the eggs are deposited in the ground and covered with plant matter. This species was observed providing parental care. The female lies on her side cradling her clutch of eggs, and later the larvae. This behavior was reported to proceed for several weeks. The female applies an antifungal secretion by mouthing the eggs. As its diet shows, it is a very beneficial species.


On the other hand most millipedes are slower than centipedes, and feed on leaf litter and detritus. They are distinguished by the fusion of each pair of body segments into a single unit, giving the appearance of having two pairs of legs per segment. Around 10,000 species have been described, which may represent less than a tenth of the true global millipede diversity .The name "millipede" is a compound word formed from the Latin roots milli ("thousand") and ped ("foot"). Despite their name, millipedes do not have 1,000 legs, although one rare species has up to 750. Common species have between 36 and 400 legs. Most millipedes eat decaying leaves and other dead plant matter, moisturising the food with secretions and then scraping it in with the jaws. However they can also be a minor garden pest, especially in greenhouses where they can cause severe damage to emergent seedlings. Signs of millipede damage include the stripping of the outer layers of a young plant stem and irregular damage to leaves and plant apices. Very few species are carnivores.

The millipede's most obvious feature is its large number of legs. Having very many short legs makes millipedes rather slow, but they are powerful burrowers. With their legs and body length moving in a wavelike pattern, they easily force their way underground head first. They also seem to have some engineering ability, reinforcing the tunnel by rearranging the particles around it. Their bodies have segmented sections which makes them move in a wave-like form.

The head of a millipede is typically rounded above and flattened below and bears large mandibles. The body is flattened or cylindrical, with a single chitinous( what their outer body is made of) plate above, one at each side, and two or three on the underside. In many millipedes, these plates are fused to varying degrees, sometimes forming a single cylindrical ring. The plates are typically hard, being impregnated with calcium salts

Unlike centipedes and other similar animals, each segment bears two pairs of legs, rather than just one. This is because each is actually formed by the fusion of two embryonic segments, and is therefore properly referred to as a "diplosegment," or double segment. The first few segments behind the head are not fused in this fashion, and the first segment is legless, while the second to fourth have one pair each. In some millipedes, the last few segments may also be legless. The head contains a pair of sensory organs known as the tomosvary organs. These are found just posterior and lateral to the antennae, and are shaped as small and oval rings at the base of the antennae. They are probably used to measure the humidity in the surroundings, and they may have some chemoreceptory abilities too. Millipede eyes consist of a number of simple flat lensed ocelli arranged in a group on the front/side of the head. Many species of millipedes, such as cave-dwelling millipedes, have secondarily lost their eyes.

Male millipedes can be differentiated from female millipedes by the presence of one or two pairs of legs modified into gonopods. These modified legs, which are usually on the seventh segment, are used to transfer sperm packets to the female during copulation. A few species are parthenogenetic, having few, if any, males.

Females lay between ten and three hundred eggs at a time, depending on species, fertilising them with the stored sperm as they do so. Many species simply deposit the eggs on moist soil or organic detritus, but some construct nests lined with dried faeces.

The young hatch after a few weeks, and typically have only three pairs of legs, followed by up to four legless segments. As they grow, they continually moult, adding further segments and legs as they do so. Some species moult within specially prepared chambers, which they may also use to wait out dry weather, and most species eat the shed exoskeleton after moulting. Millipedes live from one to more than ten years, depending on species.

Due to their lack of speed and their inability to bite or sting, millipedes' primary defense mechanism is to curl into a tight coil — protecting their delicate legs inside an armored body exterior. Many species also emit poisonous liquid secretions or hydrogen cyanide gas through microscopic pores along the sides of their bodies as a secondary defense. Some of these substances are caustic and can burn the exoskeleton of ants and other insect predators, and the skin and eyes of larger predators As far as humans are concerned, this chemical brew is fairly harmless, usually causing only minor effects on the skin, the main effect being discoloration.

Around 15 species of millipedes are known to occour locally. The most common home encounter is The Common Millipede Pachyiulus flavipes Hanex ta`L-Indewwa or Tad-Djar is found in most local establishments where high level of humidy persists. They can be handled, and are quite docile and slow moving. This species like most have two main modes of defense if they feel threatened: curling into a tight spiral exposing only the hard exoskeleton, and secretion of an irritating liquid from pores on their body.

For more info: http://arnoldsciberras.blogspot.com/ and www.fortpestcontrol.com