LOS ANGELES - You might have thought you'd just been blessed with good fortune when you noticed that friendly little ladybug land on your shoulder.
The fact is that it may not be a ladybug at all and it's definitely not your friend.
It could be a Multicolored Asian Lady Beetle, and the bad news is: It bites.
There is, however, a method for spotting the subtle the difference between them and their friendly, harmless counterpart the native ladybug, referred to as ladybird beetles in Europe.
The difficulty comes in the comparison: Multicolored Asian Lady Beetles are nearly identical to native ladybugs to the naked eye. In fact, there are actually 5,000 different species of these insects all with different appetites, according to National Geographic.
While the native ladybug is generally harmless to humans, the Multicolored Asian Lady Beetle truly has an appetite for destruction.
Native to Asia, the insect was imported and released as early as 1916 in an attempt to control certain insect pests, according to the U.S. Department of Agriculture.
While beneficial in some regards, this beetle is somewhat of a mixed blessing. "It's tendency to overwinter in homes and other buildings, sometimes in large numbers, may make them a nuisance to many persons," says the USDA.
According to Penn State College of Agricultural Sciences, these critters will likely bite and have a yellowish defensive chemical that leaves a foul-smelling odor behind. According to the university, some people have reported experiencing an allergic reaction to these defensive excretions.
So how do you spot the difference? Multicolored Asian Lady Beetles are a little bit larger than your common ladybug. Their big giveaway, however, is the giant black "M" design in the center of their head.
If you face an infestation at your home, your first instinct might be to sweep or vacuum the insects, but that could actually agitate them, causing them to release their noxious yellow chemical.
The USDA recommends finding and sealing any openings to your house as a way of preemptively dealing with these invasive critters.
"Lady Beetles that enter wall spaces in the fall may remain there, without entering living areas, until they depart in spring to search for food. But some may become active on warm days in late winter or early spring and move into living areas," says the USDA.