You may have spotted these creepy crawlies in damp areas around your garden or found your pathways invaded with a colony of millipedes after rain and wondered where they all came from!
Millipedes are beneficial to the recycling of dead plant material in gardens, and while they aren’t harmful to humans, they are certainly considered a pest, appearing unexpectedly at your home or business, causing damage to flooring and upholstery.
While we haven’t taken the time to count their individual legs, experts have confirmed that although the name millipede literally refers to one thousand feet – ‘milli’ meaning one thousand and ‘pede’ meaning foot – millipedes do not have a thousand little legs!
Millipedes are not insects; they are actually considered myriapoda, a category which translates in Ancient Greek to “ten thousand foot.”
In Australia, we host many known species of millipedes, some of which are native to our country, but many of which are not.
One of the most notorious species of millipede to invade Australia is the Portuguese millipede, which has steadily increased in numbers over time.
Portuguese millipedes are found across the expanse of southern Australia, from Perth across to Melbourne and up to southern Queensland. They can generally be found in grassland, suburban gardens and woodlands, where they can hide under leaf littler, mulch and gardens covered with low-lying plants.
As the name suggests, Portuguese millipedes (Ommatoiulus moreletii) aren’t native to Australia; in fact, the first Portuguese millipedes weren’t found in Western Australia until 1986.
These myriapoda, which are native to Portugal and southwest Europe, were first spotted in Port Lincoln, South Australia in 1953, likely to have been introduced via ships docking from overseas. Other ports along 20th century shipping routes also experienced the arrival of Portuguese millipedes during this era.
Millipedes are related to centipedes and thus share some similarities in their appearance. However, millipedes feature some considerably noticeable differences, including more legs per section of body and a more rounded appearance.
The size and colour of millipedes may vary depending on species; however, mature Portuguese millipedes are black and can be between 20-45mm long! Native millipedes have a slightly bumpier look when compared to their invasive Portuguese millipede counterparts
From afar, millipedes look like they have more legs than centipedes; upon closer inspection, this can be confirmed by identifying the appearance of at least two pairs of legs per body segment.
When disturbed, Portuguese millipedes will do one of two things:
When threatened, Portuguese millipedes may also release a pungent, yellow secretion made of organic chemicals known as quinones, as a defence, which is designed to discourage their predators.
The noticeable physical differences between millipedes and centipedes are the centipedes flatter appearance, with only one pair of legs per body section. This means that centipedes have far less legs than millipedes.
Centipedes also tend to move much faster and also produce a nasty bite with their pincer-like appendages that can inject venom into their victim’s wound. Although a centipede bite can be painful to the victim, the bite is rarely fatal.
Portuguese millipedes stay hidden in the soil during the hot, dry Australian summers, often emerging in autumn when the weather is a little damper, as well as in spring when the temperatures begin to increase.
You will normally find Portuguese millipedes outdoors in damp areas, feeding on plant matter such as leaf litter, damp wood, mosses and even vegetables. They are recyclers, consuming and breaking down nutrients before returning the nutrients back to the soil.
Portuguese millipedes are known to congregate in large numbers, which explains the seemingly mass invasion of them after there is a shower or rainy period.
After periods of drought and after the first rains, you may find that some Portuguese millipedes have crept into your home. If you’ve woken to an invasion of Portuguese millipedes in your home – what should you do?
Portuguese millipedes are nocturnal, conducting their activity at night and they are attracted to light, which may lead to them entering homes and businesses. Thanks to their defence mechanism – the pungent yellow secretion – they can stain and cause damage to upholstery and carpets.
However, the millipedes won’t last long inside your home; when they are outside of their natural habitat and without the access to their usual food, the millipedes will likely only last two to three days before they die.
If Portuguese millipedes have invaded your home en masse, the first step is to call the professionals at The Pest Guys.
Portuguese millipedes, particularly the adult males, are interesting creatures. Adult males are known as periodomorphic, meaning that the males can come in two alternating forms: non-sexual males and sexual males.
The sexual males can be found from late summer to spring, with a special segment of their bodies that is designed for mating with the females. When the males moult, they lose their gonopods (modified mating legs), making them unable to mate again until they reach their sexual form again the next year!
Mature female Portuguese millipedes will make a small hole in the soil a few centimetres under the surface where they will lay about 200-250 small white eggs. These eggs are yellowish-white in colour and are only the size of a pinhead!
From these small eggs hatches into a pupoid, which is a legless, immobile millipede. This stage is only brief, before the pupoid grows into a juvenile millipede.
Juvenile millipedes have only three to four pairs of legs and are light brown and striped in colour; as they develop, the millipedes grow more body segments and legs until they reach full adult size.
It takes around two years for juveniles to develop into mature, breeding adult millipedes.
You can take control of millipede invasions around your home by removing leaf litter around the perimeter of your home that the millipedes may feed on, turning off external lights that may attract millipedes and putting in physical barriers to stop the millipedes from getting into the crevices under your home.
However, the most important step to combat your millipede problem is to call a pest control company with experience in millipede control – like The Pest Guys.
Contact The Pest Guys today for trustworthy, efficient services from Perth’s top pest control company.