Latrodectus geometricus, commonly called the brown widow spider, is one of the most common widow spiders that can be found in the United States. Its range is restricted to the warm Southern States ranging from California to Florida and South Carolina as well as Hawaii. It is not a native US species and has been brought in from Africa where it is called the button spider. Over the last years, the brown widow has spread greatly, especially in Southern California. In some areas, the spider has become so invasive that is has pushed the more dangerous native Western black widow out of its habitat.
Similar to the Northern black widow, the Western black widow and the Southern black widow, the brown widow’s bite transfers a strong venom that can cause strong symptoms. However, the brown widow is considerably less dangerous than its black widow relatives.
Brown Widow Description
Like all other North American widow spiders, the Brown Widow has a characteristic hourglass shape on its bottom. In contrast to the markings of its relatives, the hourglass shape of the brown widow is usually orange or light read instead of a dark red. Its legs are light brown with several black rings around it.
The back of the abdomen is adorned with several black, brown and red markings. These markings have led to its scientific species name L. geometricus.
A great way to identify a brown widow and to distinguish it from the similar looking, but harmless, Steatoda triangulosa cobweb spider is its egg sac. The egg sacs of the brown widow are spiky or tufty.
An adult female brown widow reaches a size of around 0.5 inches (13 mm). The total leg span can be up to 2 inches (50 mm). The male is generally slightly smaller than the female.
Like the other widow spiders, the brown widow spins erratic and tangled-looking webs. In many cases, the spider can be found hanging upside down in the center of the web. This reveals the hourglass shape on the bottom of its abdomen.
Brown Widow Bite
Most bites from brown widows occur when the spider feels that it is in danger and is trying to defend itself or its egg sac. Therefore, you should never touch the web of a widow with your hands. Generally, brown widow bites rarely occur, as the spider will rather run away from humans than attack them. As mentioned above, the bite of a brown widow is less severe than the bite of a black widow. The strong pain is usually limited to the direct area of the bite.
The spider doesn’t inject venom with every bite. However, if you have been bitten and you feel a strong pain, muscle cramps or nauseous, head to the nearest hospital immediately.
Range of the Brown Widow in the United States
The Brown Widow likes warm temperatures and can only be found in the Southern states of the USA. These are: Alabama, Arkansas, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, South Carolina, Tennessee and Texas.
Scientific Classification of Latrodectus geometricus
- Kingdom: Animalia
- Phylum: Arthropoda
- Subphylum: Chelicerata
- Class: Arachnida
- Order: Araneae
- Infraorder: Araneomorphae
- Family: Theridiidae
- Genus: Latrodectus
- Species: Latrodectus geometricus
Other common names
Other common names of the brown widow are brown button spider, house button spider, brown black widow, gray widow, geometric widow and geometric button spider.