Loxosceles spiders—commonly known as recluse spiders—are a group of venomous arachnids found in warm and dry environments across the world. While many people are familiar with the Brown Recluse, there are actually over 140 species in this genus, and several are known to cause medically significant bites.
In this guide, I’ll introduce 10 of the most well-known types of Loxosceles spiders, focusing on how to identify them, where they’re found, and what to know about their venom and behavior. Whether you’re curious or cautious, this list will help you recognize these reclusive spiders more confidently.
1. Loxosceles reclusa (Brown Recluse Spider)
Overview:
The Loxosceles reclusa, or Brown Recluse Spider, is one of the most well-known recluse species found in the central and southern parts of the United States. It’s often feared because its venom can damage human skin, though serious bites are rare.
Appearance
This spider is light to medium brown, often with a violin-shaped mark on its back. Its body is small compared to its legs, and it lacks strong patterns.
Identification
- Six eyes in three pairs (dyads)
- Violin-shaped marking on the cephalothorax
- Uniformly colored legs (no stripes or bands)
- Fine hairs but no spines on legs
- Body length around 6–20 mm
Habitat and Behavior
Brown recluses hide in dry, undisturbed places like basements, closets, shoes, and storage boxes. They are nocturnal hunters, feeding on small insects. Their webs are irregular and used only as shelter—not to catch prey.
Venom and Medical Concerns
While bites are rarely life-threatening, they can cause skin lesions or ulcers. The reaction varies—some heal quickly, while others may worsen without treatment. Always seek medical care if bitten.
2. Loxosceles laeta (Chilean Recluse Spider)
Overview:
The Loxosceles laeta, or Chilean Recluse, is considered the most dangerous recluse spider due to its potent venom. It is native to South America, especially Chile and Peru, but has also been found in parts of North America through accidental transport.
Appearance
This species is light brown to reddish-brown and slightly larger than the Brown Recluse. It also has a violin-shaped mark, but the body and legs are longer and more slender.
Identification
- Six eyes arranged in three pairs
- Darker violin marking than L. reclusa
- Body length up to 15 mm (larger than most Loxosceles)
- Legs noticeably longer
- Uniform leg color with fine hairs
Habitat and Behavior
They hide in dark, dry places indoors like closets, under furniture, or storage areas. Outdoors, they prefer woodpiles or sheds. They are active at night and non-aggressive but may bite when trapped.
Venom and Medical Concerns
Their venom contains a strong necrotic toxin that can cause deep skin ulcers, tissue death, and in rare cases, systemic reactions like fever, vomiting, or kidney failure. Medical care is highly recommended after a bite.
3. Loxosceles rufescens (Mediterranean Recluse Spider)
Overview:
The Loxosceles rufescens, known as the Mediterranean Recluse, is native to the Mediterranean region, including parts of Europe, North Africa, and the Middle East. It has spread globally through human activity and is often found in warmer climates.
Appearance
This spider is usually pale brown to grayish-brown, sometimes with a faint violin mark. It’s slightly smaller than the Brown Recluse and often goes unnoticed due to its shy, hidden lifestyle.
Identification
- Six eyes in three closely grouped pairs
- Faint or no visible violin marking
- Body length around 7–10 mm
- Smooth, pale-colored legs
- Small and less hairy than L. laeta
Habitat and Behavior
Often found in old buildings, basements, or rock walls, especially in dry, undisturbed areas. It avoids contact and hides well during the day. It spins loose webs in corners and cracks.
Venom and Medical Concerns
While its venom is less potent than L. laeta, it can still cause painful bites and skin reactions. Severe cases are rare, but bites should still be treated with caution and monitored for complications.
4. Loxosceles deserta (Desert Recluse Spider)
Overview:
The Loxosceles deserta, or Desert Recluse, is found in the southwestern United States, particularly in Arizona, California, and Nevada. It thrives in arid desert climates and is closely related to the Brown Recluse.
Appearance
It is light tan to yellowish-brown, with a pale violin marking. Compared to L. reclusa, it tends to be lighter in color and often mistaken for other small desert spiders.
Identification
- Six eyes arranged in three pairs
- Faint violin marking pointing toward abdomen
- Body length around 7–12 mm
- Long, uniformly pale legs
- Fine hairs on body, no strong spines
Habitat and Behavior
Prefers hot, dry areas, often found under rocks, logs, or desert debris. Indoors, it hides in dark corners, storage boxes, or behind furniture. It’s nocturnal and uses its web only as a retreat.
Venom and Medical Concerns
The venom can cause localized tissue damage, but severe necrosis is less common than with L. laeta. Most bites heal with basic care, but some may require medical attention.
5. Loxosceles arizonica (Arizona Recluse Spider)
Overview:
The Loxosceles arizonica is a lesser-known recluse spider found in Arizona and surrounding regions. It is native to desert and semi-arid areas and rarely seen inside homes.
Appearance
It has a yellowish-brown body and legs, often with a subtle violin mark on its back. It’s similar in size and shape to L. deserta, but slightly darker in tone.
Identification
- Six eyes in three pairs
- Subtle violin-shaped marking
- Body length 6–10 mm
- Smooth, yellow-brown legs
- Uniform body color, no distinct patterns
Habitat and Behavior
Lives mainly outdoors, under stones, bark, or desert shrubs. It does not commonly enter buildings. Active at night and hides well during the day.
Venom and Medical Concerns
Bites are rare and usually not severe. The venom is milder than in other Loxosceles species, but may still cause redness, swelling, or itching. Seek care if symptoms worsen.
6. Loxosceles devia
Overview:
Loxosceles devia is native to South America, especially found in Brazil and Argentina. It is less commonly known but still part of the recluse spider group, with venom that can affect human skin.
Appearance
It has a light to reddish-brown body, often with a very faint or no violin marking. Its legs are long and slender, and its body is slightly more elongated compared to other species.
Identification
- Six eyes grouped in three dyads
- Body length around 8–12 mm
- Pale legs with no bands
- Faint or absent violin mark
- Narrow, elongated body shape
Habitat and Behavior
Often found in forest edges, woodpiles, or rural structures. It builds simple web retreats and prefers quiet, hidden spots. It rarely comes indoors.
Venom and Medical Concerns
Bites are not commonly reported, but when they occur, symptoms may include itching, mild pain, or small ulcers. Severe reactions are rare, but it’s wise to monitor any bite closely.
7. Loxosceles gaucho
Overview:
Loxosceles gaucho is a well-documented species found in Brazil. It is one of the more aggressive South American Loxosceles species and has a potent venom capable of causing serious effects.
Appearance
It is typically brown to dark brown, with a distinct violin marking. It is similar in size to the Brown Recluse but with a darker, shinier look.
Identification
- Six eyes in three pairs
- Bold violin marking on cephalothorax
- Body size 8–13 mm
- Smooth legs with fine hairs
- Abdomen slightly darker than thorax
Habitat and Behavior
This spider prefers urban environments, hiding in houses, attics, or cluttered areas. It is more adaptable to human environments than many other species.
Venom and Medical Concerns
The venom can cause serious skin necrosis, and in some cases, systemic reactions such as fever or muscle pain. It is one of the more medically important species in South America. Seek immediate medical care after a suspected bite.
8. Loxosceles intermedia
Overview:
Loxosceles intermedia is one of the most clinically important recluse spiders in Brazil. It is well-studied due to its frequent contact with humans and the severity of its bites. Many medically reported bites in southern Brazil are linked to this species.
Appearance
It has a light to medium brown body, with a clearly visible violin-shaped marking. Its overall appearance is very similar to other Brazilian recluse spiders, making it hard to distinguish without close examination.
Identification
- Six eyes arranged in three pairs
- Pronounced violin marking on cephalothorax
- Body size around 7–12 mm
- Smooth, pale brown legs
- Slightly shiny body texture
Habitat and Behavior
Common in urban homes, especially in storage areas, clothing, and under furniture. It is nocturnal, reclusive, and builds loose web retreats. Frequently encountered by people due to its indoor habits.
Venom and Medical Concerns
Its venom is highly necrotic, often causing deep ulcers, skin death, and long healing times. Systemic effects like fever and vomiting may occur in severe cases. Medical help is strongly advised.
9. Loxosceles spinulosa
Overview:
Loxosceles spinulosa is a South American recluse spider found in parts of Argentina and Brazil. Though not as widely known as L. laeta or L. intermedia, it belongs to the same group and has similar venomous capabilities.
Appearance
It has a pale brown to orange-brown body, usually with a subtle violin marking. It’s small to medium-sized, with long, fine legs and a narrow body profile.
Identification
- Six eyes grouped in three dyads
- Faint or no visible violin shape
- Body length around 6–10 mm
- Thin, delicate legs with light hair
- Smooth, evenly colored body
Habitat and Behavior
Found in dry, protected outdoor spots such as under rocks, in woodpiles, or behind bark. Indoors, it may hide in rarely used rooms or storage spaces. It is nocturnal and reclusive.
Venom and Medical Concerns
Though less commonly involved in bites, it has necrotic venom and may cause mild to moderate skin damage. Bites should be treated seriously, and symptoms monitored closely.
10. Loxosceles similis
Overview:
Loxosceles similis is a lesser-known recluse spider species found in South America, especially in Brazil. As the name suggests, it is very similar in appearance and behavior to other Loxosceles species, especially Loxosceles laeta and Loxosceles intermedia.
Appearance
It has a light brown to reddish-brown color, with a faint violin mark on its back. It’s small and often overlooked due to its close resemblance to other recluse spiders.
Identification
- Six eyes in three pairs (dyads)
- Violin mark is present but less defined
- Body length around 7–10 mm
- Legs are long and uniformly colored
- Slim body with smooth surface
Habitat and Behavior
Found in secluded areas, such as cracks in walls, behind furniture, or storage spaces. It is nocturnal, avoids light, and does not build traditional webs—just retreat silk shelters.
Venom and Medical Concerns
Its venom is necrotic, though less aggressive than L. laeta. Bites may cause redness, swelling, or mild skin lesions, and should be treated with basic wound care and monitored for signs of worsening.
