Have you recently seen a black spider (Badumna insignis) in your garden that look like grey-house spider or Badumna longinqua but have white dots? 
So, you’re wondering how venomous is a black spider with white dots?
Well, most black spiders with white spots are jumping spider that aren’t venomous to humans. However, other similar species like the immature black widow are very poisonous. But this is just a faction of the 3,000 spider spices found in North America. Thus, you must know how to differentiate the spider species.
Details: How Venomous is a Black Spider with White Dots?
The Phidippus audax (Jumping Spider) with black and white spot or bands at the back of their abdomen are the most common jumping spiders but aren’t venomous. You’ll find them around the house and in your gardens or lawns.
1. Jumping Spider
As noted above, jumping spiders make the largest percentage of the black spiders that have black spots. However, the jumping spiders won’t be venomous to humans.
Jumping spiders are named due to their leaping after stalking their pray as they hunt for a suitable meal. You’ll notice that the arachnid has a fuzzy look.
The jumping spiders’ body is black but its spots vary with the species. However, the spiders have white spots on its back but also have white bands on their legs.
Related: Do Spiders Have Lungs?
2. Wolf Spider
Similar to the jumping spiders, on their appearance, are the Wolf spiders also have a body that is fuzzy dark with white spots or markings.
But the wolf spiders will mainly have shades of gray as opposed to white or stark black. They also are about 1 inch in body length (without the legs) and medium-sized.
Wolf spiders won’t be poisonous or generate any venom that may paralyze their prey including insects but not to humans. For humans, bites from wolf spider are painful and dangerous than bee stings.
Therefore, Wolf spiders bite must be taken care or treated by a professional medical officer or doctor – despite the bites not being venomous to humans.
3. Crab-like Spiny Orb Weaver
The Spiny Orb-Weaver bites aren’t venomous – and aren’t equally an aggressive spider species. In fact, these spiders won’t bite humans unless you’ve provoked in any way.
But when you look at the Spiny Orb-Weaver, you might not even notice that you’re facing a spider. First, you’ll notice its abdomens that are odd-shaped plus having spiny protrusions making it look like a crab.
Some Spiny Orb-Weavers will have their abdomens being black in color plus the white spots or white/ red markings or vice versa – but aren’t venomous to humans.
Related: Do Spiders Have Ears?
4. White-Backed Garden Spider
These white-backed garden species also have the white spots or markings on their black back.
But the spots might be yellow, cream or white appearing on a back that’s muted black as opposed to the black widow or deep black.
The spider’s legs will have yellow, white, or black banks while its abdomen is leaf or oval shaped. However, the white-backed garden spiders are excellent pest control agents.
5. Black Widow Spider
National Geographic state that black widows are highly venomous – infarct the most poisonous in North America. Compared to the rattlesnakes, bites from black widows are 15 times more venomous.
But black widows only bite if disturbed by humans or predators when resting. The immature and male black widow spiders come with white spots while the female is conspicuous shaped like a red hourglass.
The spots on this spider will run on its back and sides. Further, you’ll see, on its big abdomen, some cleanly outlined spots – while only females are very venomous.
Related: Do Spiders Have Hearts?
Black widow’s Venom
As noted above, Black widows are very venomous while only the females will threaten the life of human beings. But these spiders don’t major harm to humans – but this is different from the sick, very old, and very young.
The bites from these spiders feel and appear like the pin-prick with the pain spreading withing very few minutes in the human body. The pain from Black widows bites could last for about 8-12 hours as detailed by OSHA.
But the species of this Black widows will determine the effects which may include diaphragm paralysis, severe back pain,nausea, and muscle aches.
