Six-Eyed Sand Spider — spider of medium-sized deserts and other sandy places in southern Africa. It is a member of the araneomorph spider family, and close relatives of this spider are sometimes found in both Africa and South America. His closest relatives — recluse spiders that are found all over the world.
Origin of the species and description
Photo: Six Eyed Sand Spider
The six-eyed sand spider is also known as the six-eyed crab spider due to its flattened stance and laterid legs. It is believed that the poison from the bite of these spiders — the most dangerous among all spiders. Six Eyed Sand Spider — it is a living fossil that predated the drift of Gondwanaland about 100 million years ago and is also found in South America. There are 6 species distributed in the Western Cape, Namibia and the Northern Province.
They are found:
- in the sand;
- on sand dunes;
- under rocks and rock ledges;
- in close proximity to ant pits.
Video: Six-Eyed Sand Spider
The six-eyed sand spider from the Northern Cape and Namibia is arguably the deadliest spider in the world. Luckily, due to its habitat, it is rare and doesn’t seem to want to bite. However, this spider should not be handled as there is no effective treatment for its venom.
Fun fact: The scientific name for the family of the six-eyed sand spider — Sicarius, which means “murderer” and “sica” — curved dagger.
The genus to which the six-eyed sand spider belongs was first created in 1878 by Friedrich Karsch as Hexomma, with the single species Hexomma hahni. However, by 1879 Karsh realized that the name was already in use in 1877 for a species of cleaner, so he published the replacement name Hexophthalma.
In 1893, Eugène Simon transferred Hexophthalma hahni to the genus Sicarius and Hexophthalma fell into disuse until a phylogenetic study in 2017 showed that the African species of Sicarius, including the six-eyed sand spider, were different and revived the genus Hexophthalma for them. Two new species were added to the genus in 2018, and one previously accepted species, Hexophthalma testacea, is synonymous with the six-eyed sand spider. Species are expected to increase with further research.
Appearance and Features
Photo: What a six-eyed sand spider looks like
The six-eyed sand spider has 6 eyes arranged in 3 dyads, which are widely spaced in a curved row. The cuticle is leathery with curved setae and is usually burgundy or yellow in color. The six-eyed sand spider is covered in fine hairs called chaetae (coarse hair, bristle, bristle-like process, or body part) that serve to hold sand particles. This provides effective camouflage even when the spider is not buried.
The six-eyed sand spider has a body length of up to 15 millimeters, and a paw width of about 50 millimeters. Most species are reddish brown or yellow in color without any distinct patterns. Six-eyed sand spiders often camouflage themselves with grains of sand sandwiched between body hairs to blend in with the background of their particular habitat. Six-eyed sand spiders are shy and secretive, but they will bite if accidentally contacted.
Fun fact: Six-eyed sand spiders can live up to 15 years, four times as long as the average spider.
These free-living spiders — terrestrial animals and have a uniform yellowish brown overall color. Six-eyed sand spiders appear dusty sandy and take on the color of the ground they live in.
Where does the six-eyed sand spider live?
Photo: Six-eyed sand spider in Africa
Based on evolutionary data, relatives of the six-eyed sand spiders are believed to have originated in western Gondwana, which is one of two supercontinents that existed about 500 million years ago. Since they colonized this land a long time ago, these spiders are sometimes referred to as “living fossils”. The current distribution of the family of these spiders is mainly in Africa and Latin America. This divergence is thought to have occurred when the supercontinents separated approximately 100 million years ago, separating Africa from the Americas.
The six-eyed sand spider can be found in the sandy regions of South and Central America. This spider lives in the desert and hunts in ambush. Unlike most hunters who wait in ambush for prey, the six-eyed sand spider does not burrow. Instead, it hides right under the surface of the sand. It has venom that is potentially lethal, can harm the heart, kidneys, liver, and arteries, and cause flesh to rot.
These spiders don’t make webs, but instead lie half in sand, waiting for prey to pass by. They are widely distributed, but are more common in dry areas. The six-eyed sand spider has a poor sense of direction, unlike other spider species.
Now you know where the six-eyed sand spider is found. Let’s see what it eats.
What does the six-eyed sand spider eat?
Photo: Six-eyed sand spider in nature
The six-eyed sand spider does not wander in search of prey, it simply waits until an insect or scorpion passes. When he does this, he grabs the prey with his front legs, kills it with poison and eats it. Six-eyed sand spiders do not need to be fed very often, and adult spiders can live for a very long time without food and water.
The six-eyed sand spider catches its prey by hiding under the sand. It lifts its body, digs a hole, falls into it, and then covers itself with sand using its front paws. He catches prey with his front paws when the victim runs across the hidden spider. If a six-eyed sand spider is detected, it will become covered in fine sand particles that adhere to the cuticle, acting as effective camouflage.
This spider’s main food items are insects and scorpions, and they can wait up to a year to eat their prey because once they bite their prey, they are instantly immobilized. They feed on passing insects, quickly emerging from the sand when disturbed. During self-absorption, soil particles can adhere to specialized hairs that cover the bodies of spiders, changing their natural coloration to that of the environment.
While some predators have to deal with the challenge of finding and capturing their prey, this spider allows the prey to approach it. Living modestly and sedentary, the spider camouflages itself by burrowing and sticking to sand particles and will wait until any prey gets too close. As soon as the prey is in sight, the spider emerges from the sand and bites the prey, immediately injecting deadly poison into it. The insect is immobilized immediately and death occurs within seconds.
The necrotic effects of the venom of the six-eyed sand spider are caused by the sphingomyelinase D family of proteins present in the venom of all spiders of this genus. In this respect, the genus resembles hermits. However, most species have been little studied, and the detailed effects of their venom on humans and other vertebrates are unknown.
Character and Lifestyle Features
Photo: Six Eyed Sand Spiders
Fortunately, this spider, like the recluse spider, is very shy. However, studies have shown that this spider venom is the most poisonous of all spiders. There is some question as to the danger this spider poses. Although it is very shy and unlikely to bite humans, there are few (if any) recorded human poisonings by this species.
However, studies have shown that the poison is particularly potent, with a powerful hemolytic effect (rupture of red blood cells and release of hemoglobin into the surrounding fluid) and necrotic effect (accidental death of cells and living tissue), causing blood to leak from vessels and tissue destruction.
The bite of the six-eyed sand spider causes many problems, including:
- leakage of blood vessels;
- blood thinning;
- tissue damage.
Unlike dangerous neurotoxic spiders, there is currently no antidote for this spider’s bite, leading many to suspect that this spider’s bite can be fatal. There were no confirmed human bites, there were only two suspected cases. However, in one of these cases, the victim lost an arm due to massive necrosis, and in another, the victim died from severe bleeding, similar to the effects of a rattlesnake bite.
Fun fact: The six-eyed sand spider rarely comes into contact with humans, and even when it does, it usually never bites. Also, like most spiders, it doesn’t always inject venom with every bite, and even then it doesn’t necessarily inject large amounts.
Thus docile behavior and natural the history of six-eyed sand spiders has resulted in very few recorded bites, so the symptoms of their bites in humans are poorly understood.
Social Structure and Reproduction
Photo: Six Eyed Sand Spider
Six-eyed sand spiders reproduce by laying eggs in silken bundles called egg sacs. Spiders often use elaborate mating rituals (especially in visually advanced jumping spiders) to allow the male to get close enough to inseminate the female without eliciting a predatory response. Assuming mating start signals are exchanged correctly, the male spider must make a well-timed departure after mating in order to escape before the female eats it.
Like all spiders, the six-eyed sand spider is capable of producing silk from its abdominal glands. This is commonly used to create webs such as spiders that are seen every day. The six-eyed sand spider does not make webs, however, it does use this unique ability to make silk bundles called egg sacs to surround its eggs.
Fun fact: An egg sac is made up of many sand particles , which are glued together with the help of silk obtained by the spider. Each of these egg sacs can hold many young.
These spiders spend a surprisingly large part of their lives in close association with sand, so it makes sense that they end up in a world mostly submerged in it. Because these spiders hide under the sand for most of their days, when the male approaches the female to mate, he does so slowly so as not to cause a fight or flight response from the female spider.
Natural enemies of six-eyed sand spiders
Photo: What a six-eyed sand spider looks like
Six-eyed sand spiders have no natural enemies. They themselves are enemies for those who try to approach them. All members of the genus to which it belongs are capable of producing sphingomyelinase D or related proteins. It is a potent tissue-destroying agent unique to the spider family, which is otherwise found only in a few pathogenic bacteria.
The venom of many Sicariidae species is highly necrotic in effect, capable of causing damage (open wounds). Wounds take a long time to heal and may require skin grafting. If these open wounds become infected, it can lead to serious consequences. Rarely, the poison is carried by the bloodstream to the internal organs, causing systemic effects. Like their close relatives, the recluse spiders, the venom of the six-eyed sand spider — powerful cytotoxin. This poison is both hemolytic and necrotic, meaning it causes blood vessels to leak and flesh to break down.
Most people bitten by a six-eyed sand spider simply got too close to its hiding place. There are ways to try to reduce the spider’s damage, but there is no specific antidote available. To avoid damage, it’s best to avoid this spider entirely, which shouldn’t be that difficult for most people when considering its habitat.
Population and Species Status
Photo: Six Eyed Sand Spider
Over 38,000 species of six-eyed spiders have been identified, however, due to their great ability to hide, it is believed that there are about 200,000 species. The natural habitat of the six-eyed sand spider is rapidly expanding due to the reluctance of the spider to go far from home. Based on data collected by examining the various exoskeletons that these spiders hid throughout their lives, individuals remain in the same place for most, if not all, of their lives.
Another reason for this is that their dispersal methods do not include the bloat that other spider species exhibit. The habitat of the six-eyed sand spider usually consists of shallow caves, crevices and between natural ruins. They are most common in shallow sand patches due to their ability to bury themselves and stick to sand particles.
The family Sicariidae contains the well-known and dangerous loxosceles species. The other two genera of the family, Sicarius and Hexophthalma (six-eyed sand spiders) have exclusively cytotoxic venom, although they live in sandy deserts and rarely come into contact with humans.
The six-eyed sand spider is a medium-sized spider that can be found in deserts and other sandy places in southern Africa with close relatives found in both Africa and South America. The six-eyed sand spider is a cousin of the recluse spiders found throughout the world. The bites of this spider rarely threaten humans, but have been experimentally shown to be fatal to rabbits within 5-12 hours.
