Spiders can live in the grass of your lawn, the leaves of your houseplant, the dark recesses of your garage, or the hidden places of your home. For many people, spiders may also live in their nightmares.
While arachnophobia - fear of spiders - may be based on some legitimate trauma of being bitten or walking into a spider web, some psychologists believe our aversion may be part of our genetic hard-wiring.
In Florida, the warm climate and lush vegetation makes the state a year-round paradise for spiders. There are 59 identifier spider species here and because there are so many kinds, it’s important to understand what spiders are, what they mean to the environment, which ones are beneficial and which can be potentially harmful.
What are Spiders?
Many people believe spiders to be a type of insects when they are actually a type of arthropod known as an arachnid. Where insects have three body parts, spiders have two. Where insects have six legs, spiders have eight. Spiders also differ from insects in their ability to extrude silk which they use for making webs and capturing prey.
All spiders are venomous, with the exception being a small family of tiny orb weavers. Venom is what spiders use to kill their prey, which is usually insects. Worldwide, spiders eat between 400 to 800 million metric tons of insect a year, making them one of the most effective natural pest control allies Floridians can have. And fortunately, the good spiders in the Sunshine State outnumber the bad.
Dangerous (Highly Venomous) Florida Spiders
There are two species of potentially dangerous spiders in Florida and both prefer sheltered, dimly lit places like basement corners, woodpiles, or debris piles. Victims are often unaware of their presence until they feel the spider’s bite, which is why it is always important to wear gloves when working in areas where they may be present.
Widow Spiders (Latrodectus):
Most people are aware that Florida is home to the Southern black widow spider, but what they may not know is that there are three other species of widow spiders here as well - the Northern widow, the brown widow, and the red widow.
With widows, it is the larger, colorful females that are potentially dangerous and the ones you’re most likely to see guarding their egg sacs. Black widows are most recognizable, being completely black save for the red hourglass design on the underside of their large abdomens. Both southern and northern black widows look similar. The brown widow can be grayish to tan rather than black, with a diagonal marking on the upper abdomen and a rust-colored hourglass on the underside of the abdomen. But the most distinctive feature of the brown widow is its egg sac, which is covered in spiky apertures. The red widow is the rarest of the Florida widow spiders, and is listed as a threatened species. The female has a reddish-orange head and legs and a black abdomen with an incomplete hourglass design on the underside.
Widows are the most venomous spiders in North America. Widow venom is a neurotoxin that affects the nervous system and causes severe pain and in some cases can be fatal. If you are bitten, seek immediate medical care.
Recluse Spiders (Loxosceles)
Florida is home to three species of recluse - the brown recluse, the Chilean recluse, and the Mediterranean recluse. While not a native species, recluse spiders have established themselves in the state, and all share the distinctive upside-down violin-shaped marking on the upper body which may be difficult to see since the spiders aren’t very big. Brown recluses range from drab sandy to dark brown while the Mediterranean recluse is brown. The Chilean recluse is light yellow to reddish-brown and is the largest of the three recluses, with legs longer than its body.
While usually not fatal, recluse bites can be painful and require medical attention. Recluse venom contains both a hemotoxin that causes excessive bleeding and a cytotoxin that may cause necrosis.
If you suspect you’ve been bitten by a black widow or brown recluse, call the Poison Control Center 24-hour hotline at 1-800-222-1222.
Beneficial (Non-Dangerous) Florida Spiders
Your lawn is probably home to multiple spider species that are not only perfectly safe but spend their days offering free pest control. Here are a few you may encounter.
Garden Spiders (Agriope):
Also known as the writing spider, this spider is known for its distinctive yellow and black markings and webs with a zig-zag design. Garden spiders are non-aggressive and large enough to eat cicadas, cockroaches, grasshoppers, and other insects that many Floridians would rather see less of.
Golden Silk spiders (Nephila):
The largest non-tarantula species of spider in the world, these impressive orb-weavers are sometimes called banana spiders because of their elongated thoraxes. For people who become terrified of walking into webs, be warned: these spiders build massive golden webs on trees and low shrubs, and it’s not uncommon to find multiple Nephila constructing webs in one yard. While their size also makes them intimidating, they are mild mannered and non-aggressive.
Huntsman Spider (Heroptoda):
At about six inches from leg to leg, the ground-dwelling huntsman spider is the largest of Florida arachnids.It doesn’t spin a web, but is an “active hunter” that catches and subdues its prey with its jaws. Because of its size, the huntsman may deliver a painful bite if picked up. However, it does not have a strong venom and is not an aggressive species.
Spiders Common to Florida Homes
Not all spiders prefer living outdoors. Homeowners should always be mindful to check garages or dark corners for widows and recluses. Here are some other spiders that may share your home without causing as much concern.
Jumping Spiders (Salticidae):
These tiny, fuzzy spiders can be found on the leaves of indoor houseplants, where they stalk and pounce on prey almost as big as they are. Jumping spiders are one of the few arachnids that have become popular photography models because their large eyes give their faces a distinctive, almost expressive appearance.
Golden Sac Spider (Cheircanthium):
These nocturnal hunters can more commonly be seen in the fall when they follow other insects into the warmth of your home. Golden sac spiders are small and beige to light yellow with a slight greenish tint. They built little silken tubes or sacs in which they hide during the day.
Domestic House Spider (Tegenaria):
These spiders that catch prey using funnel-shaped webs they build in the dark corners and crevices. They are a drab brown and can have a two-inch leg span. The legs are banded and there are tan markings on the abdomen.
Daddy Longlegs (Opiliones):
Sometimes called harvestmen, the Daddy Longlegs is an arachnid but not a true spider. Where spiders’ bodies consist of two segments, the Daddy Longlegs consists of a single segment and long, almost hairlike legs. They eat rotting vegetation and can be found in damp environments, like that neglected portion of your greenhouse you’ve been meaning to clean up. There is a myth that the venom of the Daddy Longlegs is extremely dangerous, but there’s no truth to it.
Living with Spiders In Florida
In most cases, humans and spiders can co-exist. However, it’s always a good idea to know exactly who your neighbors are, even if those neighbors have eight legs. There are many good online resources for identifying spiders in your area, and because different species occur in different parts of the state, resources like these can be especially helpful as you continue your education about which spiders are safe and which ones should be avoided.