Hello, last time on my revamp of the poisons collection I spoke about blue frogs today we’re jumping to red spiders. This may not be the best blog for any arachnophobes particularly if you’re Australian.
Today we’re going to be looking at the highly poisonous Redback Spider.
Female Redback Spider. Photo Credit – Toby Hudson
COMMON NAME: Redback Spider – red-striped spider – red-spot spider – jockey spider
SCIENTIFIC NAME: Latrodectus hasseltii
DIET: Carnivore – main sources of prey are insects, small lizards and other spiders
GROUP NAME: cluster or clutter
AVERAGE LIFE SPAN IN THE WILD:
HABITAT: Widespread across Australia, particularly common in Brisbane, Perth and Alice Springs. Often found in outside urban areas and webs are often built in sheds, outhouses and even in tyres. Webs are often in dry, dark and sheltered places.
SIZE: Females usually have a body length of about 10 millimetres (0.4 in), while the male is much smaller, being only 3–4 mm (0.12–0.16 in) long.
I will start off by saying that not all redback spider bites are venomous, if there web is disturbed they might start off by giving you a warning bit. Nevertheless if you think you’ve been bitten by a redback it is definitely best to go and get checked out.
However, venomous bites from redbacks can result in pain, swelling and redness spreading up the limb from the bite site. However 1 in 3 humans bitten will develop further symptoms called latrodectism. Symptoms typically include nausea, vomiting, abdominal or chest pain, agitation, headache, generalised sweating and hypertension. These can lead to other complications but these are rare. Nearly all the bites that end with these symptoms are from a female redback.
The majority of reported spider bites in Australia are attributed to redbacks, which are responsible for around 2,000 hospitalised bite cases each year. However, not a single death due to redback venom has been reported for 50 years, since the introduction of redback antivenom.
Photo credit: Natalie Saez
Males and females look quite different from each other. Males will often be smaller and have different colouring. They are normally light brown with white markings, but lack the distinctive red stripe that the females have. The red backs mating system is also rather perculiar, Natalie Saez from lifehacker put it perfectly:
During mating, not only does the female eat the male, but the male actually assists her in this process by flipping his body towards her so that he is closer to her mouthparts. Because the cannibalistic process is so slow, mating continues until the male succumbs to his injuries.
Hope you enjoyed this episode, I once had friends in Australia with these suckers living under their house!