Spiders are arthropods that belong to the class Arachnida and order Araneae. Spiders are grouped into various genera. These genera include species such as funnel-web spiders, orb-weaver spiders, sac spiders, wolf spiders, and hunting spiders. Some of the most frightening spiders are tarantulas in the Theraphosidae family.
Before looking at pictures of spiders and how to identify them correctly, there are a few important facts to know about spiders.
All spider species are called arachnids because they belong to the class of animals called Arachnida. This large group of leggy animals also includes mites, ticks, and scorpions. One of the identifying features of all spider arachnoids is that they have 8 legs and no antennae.
This means that spiders are not classified as insects. Although spiders and insects are arthropods, insects only have 6 legs and are in the class Insecta. Another difference when identifying spiders is that they have 2 body parts whereas insects have 3 body parts.
Because spiders are invertebrates, they don’t have bones but have an exoskeleton. This is a type of external skeleton that covers, supports, and protects spiders, ants, wasps, bees, roaches and even lobsters!
Also, although many people refer to spiders as bugs, they are not classed as bugs. In fact, not all insects are bugs because they don’t have a mouth that sucks juices. However, most people refer to any type of house pests such as spiders, ticks, mites, and flies as bugs.
Types of Spiders
Let’s look in more detail at the identifying features of the most common species of spiders that you are likely to find at home or in your garden.
While there are big fat black species of spiders such as tarantulas, mouse spider, or trapdoor spiders, this list looks at the most common spiders you will find in and around your home.
Wolf Spider Facts
Wolf spiders are a subclass of arachnid belonging to the family Lycosidae. There are thousands of spider species that are classed as ‘wolf spiders.’ The bodies of these hairy 8-legged creatures grow up to 1.38” (35 mm).
Wolf spiders bite when they are threatened. However, their bite is similar to a bee’s sting and may cause itching, swelling, and mild pain.
A type of brown spider with beige markings and quite hairy. In relation to other species of spiders, wolf spiders have large eyes and excellent vision.
You can identify wolf spiders by their distinctive eye pattern. First, you will notice two large eyes in the front of their head. Under those two eyes are a row of four smaller eyes. Wolf spiders also have two more eyes on the top of their head at either side
Brown Recluse Spider Facts
One of the most dangerous arachnids to find in your home is the brown recluse spider (Loxosceles reclusa) from the family Sicariidae. Like with other species of recluse spiders, a bite from one of these brown arachnids can require medical attention.
American House Spiders
One of the most common house spiders is the American house spider (Parasteatoda tepidariorum). These brown or tan harmless spiders usually create messy cobwebs to catch their prey.
Found throughout North America, these common spiders are generally found in basements, in attics, behind doors, and in the corners of window frames. The legs of the American house spider are often yellow/orange with dark rings.
Black Widow Spiders
Black widow spider is the common name for spiders in the Latrodectus genus belonging to the family Theridiidae. These black spiders with red dots are some of the most venomous house spiders in North America. Another poisonous species in the genus is the brown widow spider.
Other species include the European black widows (Latrodectus tredecimguttatus), Australian redback black widows (Latrodectus hasseltii), and South African button spiders.
Although the female black spiders can inflict a nasty bite, the bites rarely cause serious complications. Some common effects of a black widow bite are pain, swelling, and cramping. Species of black widow only bite when trapped and threatened.
Huntsman spiders (family: Sparassidae) are appropriately named because of their speed and agility when looking for prey. Some of the larger species are called ‘wood spiders’ or ‘giant crab spider.’
Sparassidae species can attack and bite humans to defend themselves. Because they tend to lurk in sheds, garages, and under rocks in gardens, an unsuspecting person may disturb one and get a nasty bite.
Although some class the hobo spider as an aggressive house spider, they only attack and bite if their young are threatened.
These are quite small spiders. Females can grow up to 0.39” (10 mm) excluding legs; males reach half this size at most.
Because all spiders that spin orb (circular) shaped webs are classed as orb-weavers, orb spiders are difficult to categorize as they include many species. Some are oval-shaped with a black and white body and dark red spike-like shapes. Other species can have black bodies with yellow and white markings. Or, an orb-waver spider could have a large globular colorful body with a small head.
Harmless spiders that spin intricate webs on flowers, trees, and near electric lights to catch insects.
Spiders in the family Salticidae are called jumping spiders because they jump when moving or hunting. The large eyes on the front of their body mean they also have great eyesight, something rare among other types of spiders.
Jumping spiders can also be very tiny. Some of the smallest species only measure 0.04” (1 mm) and larger ones are an inch (2.5 cm) long.
One of the most common species of sac spiders is the ‘yellow sac spider’ (Cheiracanthium inclusum and Cheiracanthium mildei). These running spiders are a yellowish-green color and can bite when provoked. The most common reasons for being bitten are disturbing them while working in the garden or if one gets trapped in clothing.
Sac spiders are a garden spider in warm weather and will invade houses in fall as they search for a warmer environment.
Cellar Spiders (Daddy Long-Legs)
Long-bodied cellar spiders (Pholcus phalangioides) belong to the family Pholcidae. These spiders also have some of the longest legs of any spider in relation to their body. Their long thin spindly legs can be as long as 6 times their body length.
Although these spiders carry venom, they are completely harmless to humans. In fact, they are classed as a beneficial spider because they consume a large number of pests such as flies, mosquitoes, and other flying nuisances. They also kill dangerous spiders such as hobo spiders and redback spiders.
Cellar spiders get their name from the fact they like to live in dark places. You will often find them in garages, on ceilings, in cellars, and in caves. Other names for them include daddy long-legs and skull spiders – this is because their cephalothorax looks like a skull.
Small oval-shaped bodies that are light tan or beige and long skinny legs make this spider species easy to identify.
Grass spiders are a species of spider belonging to the family Agelenidae. They are a medium sized brown garden spider with striped markings along the length of its body. When trying to identify this spider, you will notice distinct bands around its legs.
If you find the brown spider scurrying around grass, it is probably a grass spider. It is rare to spot these harmless brown spiders indoors.
Female grass spiders range in length from 0.39″-0.78″ (10-20 millimeters), while males are slightly smaller.
Facts about Golden Silk Spiders
Also called golden silk orb-weavers, these arachnids from the subfamily Nephilinae spin some of the most beautiful webs. Other names for this fascinating spider include ‘banana spider’ and ‘giant wood spider.’
Golden silk spiders are also very colorful spiders that range in color from red to greenish-yellow. Many species also have white markings or spots on their cephalothorax. Another unique fact about this spider species is that they spin yellow-colored webs.
To identify these interesting spiders, look for their long orange or dark tan shaped body with white spots.