What About the Ones Without Spots?
There are more than 4500 species of insects that are broadly called ladybugs. There are myths about the danger they may pose to humans.
In reality, though, most ladybugs are beneficial to us, and contrary to popular belief, they are not overly poisonous or harmful to humans. Read on!
Do Ladybugs Bite Humans?
Ladybugs do not usually bite humans, but they may do so if they face either drought or a paucity of their regular food source (aphids), caused them to start biting humans to hydrate themselves and find food.
Such behavior was spotted during at least two time periods – 1976 and 2013 – in the US.
Are Ladybugs Poisonous, or Otherwise Harmful, to Humans?
Ladybugs are not generally poisonous to humans. However, their bites can cause a painful bump at times, due to fungal infections that enter the human body from their saliva.
Additionally, some people have allergic reactions to them, which may include rhinoconjunctivitis – a painful infection caused through touching a ladybug and rubbing one’s eye afterwards.
Other potential effects could include asthma, pruritus, urticaria, angioedema, and anaphylaxis. The source of allergens is the same as the chemicals that produce a noxious odor if you happen to squash a ladybug.
For example, consider one of the most common species found in the US – the Asian Ladybug (Harmonica axyridis), also called the Asian Harlequin Lady Beetle. H. axyridis as a species can be distinguished from other commonly found ladybugs by the M-shaped black marking on their otherwise white head sections.
Asian Harlequin Beetle Compared to a Ladybug
It may be important to know the distinction between normal ladybugs and Asian Beetles, for two reasons – they are more of a pest than the average ladybug.
They have the disconcerting habit of swirling about in large numbers near our homes, especially during late Fall. However, Asian Beetles are not poisonous across the entire species.
The toxicity of a ladybug relates to their “blood” and saliva. While their mandibles are too small to cause significant damage when they bite people, there are fungi in their saliva, as mentioned above.
Plus, several alkaloid toxins are present in the hemolymph (the fluid within the ladybug) of species such as the H. axyridis. The main alkaloid, which is 2-isopropyl-3-methoxypyrazine, is also found in other insects, but in smaller quantities than in the Asian Ladybug.
These chemicals are vital for the defense and communication functions of H. axyridis and are also responsible for the noxious odor produced when the ladybug bleeds and the yellowish-red stain it leaves at the spot where it was crushed.
Are Ladybugs Poisonous, or Otherwise Harmful, to Pets?
Pets, especially dogs, are known to eat ladybugs at times.
If the ladybug happens to possess a significant amount of toxin in its hemolymph, your pet may experience something akin to a chemical burn when it crushes the insect in its mouth, which then releases chemicals that interact with the tender surfaces of the dog’s tongue and GI tract.
If your dog appears drowsy, or starts to vomit and/or displays signs of discomfort, a visit to the vet may be prudent. Another affliction may be for a dog to be unable to empty its bowels, but this is likely not due to toxins but the hard shell of the bug, which causes impaction if they cannot digest it.
Means by Which Ladybugs Protect Themselves
The bright colors sported by different ladybugs often serve as a warning to other predators to not consider them as food – this is especially true of bright red and orange, as well as shiny black.
This common trick of nature, often present in otherwise harmless insects, delivers the message is that the bug may be poisonous, foul tasting or otherwise impossible to digest.
Another method that ladybugs utilize, especially if they possess adequate quantities of the toxic chemicals that emit a noxious odor, is “reflex bleeding”.
This often involves the bug curling up into a small “turtle-like” ball and oozing some yellow and foul-smelling hemolymph from its legs. The noxious smell emanated, combined with the apparent look of death, is meant to ward off would be predators.
Is the Color Important?
The color of the ladybug can in fact be correlated with toxicity. The chemicals ladybugs produce could be connected to an abundance of carotenoids in their shell.
Examples of this are the Asian Harlequin ladybug mentioned above, or the Seven-spot Ladybug, Coccinella septempunctata.
The red or orange coloring in the Asian Harlequin or Seven Spotted Ladybugs, as shown in the photos above, is correlated with potential toxin concentration in their shells.
Are Orange Ladybugs Poisonous?
Orange-tinted ladybugs, such as the Asian or Seven-Spotted Beetles mentioned above, have a high concentration of the alkaloid toxins and can hence induce allergies in humans if they come into contact with their bodily fluids.
Are Black Ladybugs Poisonous?
Black ladybugs, especially the ones with small red spots such as the Pine Ladybugs (Exochomus quadripustulatus), are one of the most toxic varieties
Black Pine Ladybug
Ladybug specimen like the one shown above are more likely to cause a strong allergic reaction in those who are allergic to the toxic chemicals contained in their hemolymph.
Are Red, Yellow or Brown Ladybugs Poisonous?
Red ladybugs are often more aggressive, and capable of defending themselves. However, they tend not to be less toxic than orange or black colored ladybugs.
Yellow may or may not be the permanent color in a ladybug, since several species may sport yellow coloration at a younger stage in their lifecycle. Regardless, yellow ladybugs do not tend to be poisonous.
Brown ladybugs, such as the Lark ladybugs, are among the least toxic variety.
Are Ladybugs Without Spots Poisonous?
There are no hard and fast rules in terms of which ladybugs have spots and which not.
Naturalists feel that spots in a ladybug develop in order to ward off danger from predators, so there are many species which may sport specimens without spots.
For example, while H. axyridis normally show spots, they may not always do so. An example is shown below – the species can be determined given the size and markings on its head.
Asian Lady Beetle without Spots
Since the pigmentation of the exoskeleton is correlated with the potential toxin that the ladybug has, it follows that ladybugs without spots are not likely to be more, or less, poisonous than other types of ladybugs.
In general, the rule of orange and black ladybugs being more toxic than the rest still holds.
So, What’s the Worst That Could Happen?
Ladybugs are typically beneficial to us and are rarely harmful in terms of being toxic. However, you should be cautious if you experience symptoms.
As an example of how bad things can get, unexpectedly, consider the case of Reza Rezamund, a professional bodybuilder who developed severe sepsis from a ladybug bite and almost died in November 2016.
We should never ignore a ladybug bite if we exhibit unusual symptoms. Go see your doctor before something bad happens!
If you want to learn more about various insects, then checkout our site categories, we have a bunch of articles there that are totally worth reading:
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All the best
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