A couple of summers ago, we had a mimosa tree that came up in our back yard. It was a little too close to the house for my taste. I was afraid that the roots would mess up our patio or grow into the concrete walls of our basement, but my wife wanted to keep it... It has now grown almost as tall as our house. I didn’t realize how messy those trees are! For the past month, our patio and everything on it has been completely covered in sticky sap, and oh how the turntables have turned! While my wife is complaining about the constant mess, I am outside taking pictures of all the bugs it has brought in.

The ladybugs have taken a special liking to our messy mimosa. At any one time, you could go out and find the entire life cycle represented in that single tree. I thought it would be interesting to take a closer look into the lives of these helpful creatures, and I will be sharing what I have learned about them.

Today, we take a look at:

The Adult Ladybug

Ladybugs are insects from the genus Coleoptera. Their family (Coccinellidae) consists of 360 genera containing about 5,000 species worldwide, 500 of which can be found in the United States.

While ladybugs are classified as omnivores (they may subsist on raisins or other dried fruit), they really love to eat aphids. The general term “aphid” refers to any of the 1,000+ species within the family Aphididae. Almost all are small sap sucking insects that can collect in droves on plants, sometimes causing major damage, including the spread of plant viruses. It is estimated that a single ladybug can eat up to 5,000 aphids in a lifetime. For this reason, attempts have been made to introduce non-native ladybug species like the seven-spotted ladybug into the US. In fact, several attempts at this were made between the 1950s and 1970s. While those attempts failed, the species was still able to find its way over and now can be found nationwide.

I’m pretty sure that all of my ladybugs have been drawn to our mimosa tree because of the aphids. As you can see in the image below, it is covered with them! The sap brings aphids, and aphids bring ladybugs. If the supply of aphids begins to run low, the adult ladybugs will fly to where food is more plentiful.

The Aphids Are Plentiful

Ladybug Or Ladybeetle?

Ladybugs belong to the order Coleoptera. It is the largest order in the entire animal kingdom, containing almost 390,000 different species - all of them beetles! So, what makes a ladybug a beetle? Like other beetles, ladybugs have a thick outer shell that covers their wings. That thick outer shell is actually a modified forewing. You know how most insects have two pairs of wings (imagine a butterfly)? In the ladybug, the front wings have hardened to form protective wing covers called elytra over their flying wings. Beetles, including ladybugs, also have mouthparts that are made for chewing. Almost all true bugs have mouthparts designed for piercing and sucking. Finally, the life cycle of a beetle goes through a larval form that looks nothing like the adult. True bugs go through immature stages called instars, but the instar at least vaguely looks like the adult form. If you’ve ever been digging in the soil and came across a grub worm, that was the larva of some type of beetle. Ladybugs go through a larva stage of development that some have described as a tiny, alligator-like form. I’m not going to talk very much about them in this post, because I have an entire detailed article planned for that.

Identifying Ladybug Species

It is common knowledge that different ladybug species can be identified by the number of spots on their elytra. Many species’ names even imply the same. Take the seven-spotted ladybug and the nine-spotted ladybug for example. But, if there’s one thing that my science background has taught me about common knowledge, it’s that it is commonly wrong! The seven-spotted ladybug usually has seven spots, but it can vary anywhere from zero all the way up to nine, making it easy to confuse with the nine-spotted variety. Furthermore, nine-spotted ladybugs may be spotless, making them hard to distinguish from other spotless species. Boy! My head is spinning.

So, it’s obvious that we need to look at other characteristics besides just spots when trying to identify ladybug species. But, what should we look at? For many species, color patterns on the head are good indicators. For example, both the seven-spotted and the nine-spotted ladybugs have oval-shaped bodies that kind of taper off at the back end. However, you can easily differentiate between the two by looking at the coloration on their head. The seven-spotted ladybug has a mostly black head with two large white spots where we would imagine the eyes to be. On the nine-spotted, those two white spots are connected by a white line, almost like it is wearing some cool sunglasses. The multicolored asian ladybug, as the name implies, comes in several different color varieties, and it can have anywhere from 0 - 19 spots. It is best distinguished from both of the other species we’ve mentioned by looking at its body shape. With a little bit of experience, its large, plump, and rounded body can easily be distinguished from the oval-shaped body of the seven and nine-spotted bodies. Based on these characteristics, I am fairly certain that most of the ladybugs around my house are multicolored asian ladybeetles (Harmonia axyridis).

Are Ladybugs Dangerous

Back in 2015, a photo of a dog with a wad of ladybugs imbedded in the roof of its mouth started making the internet rounds. Amid the immediate cries of “photoshopped!”, a few vets and other people in the know began to confirm the validity of the picture and warn of the harm that the ladybugs could cause. A slight panic ensued, with some referring to them as vampires. It is true that ladybugs can bite - I recall being bitten once or twice as a kid. In fact, at least one experiment performed by a Cornell University student showed a propensity for ladybugs to sip a little human blood if the opportunity arises. But, this was just an example of opportunistic feeding; they weren’t out to satiate some wicked bloodlust! And, the dog with the infested mouth kinda brought it on itself by trying to eat a bunch of the things. The fact is, any type of ladybug related injuries are pretty rare. Sure, the bite hurts, but it’s nothing more than a pinch. They do not possess any type of venom or allergen that would cause itching or swelling. They do, however, have the ability to release the yellow, bitter flavored hemolymph from their leg joints as a defense mechanism. In some species like H. axyridis, the culprit in dog-mouth infestation case, the hemolymph contains alkaloid chemicals that may cause burning and irritation. That is what caused the burning ulcerated spots to form.

Again, I remember playing with ladybugs as a child, and they would often leave behind their yellow bloody residue, though I didn’t know what it was at the time. I haven’t pestered a ladybug enough for it to exude it’s defensive chemicals in quite a long time, but we bought some vetiver essential oil about a year ago to see if it would help with our son’s ADHD. Maybe I am mistaken, but as soon as I smelled it, it reminded me of that yellow stuff the ladybugs would leave on my hand as a kid. I do remember for fact that I never experienced any type of irritation or inflammation from it. Overall, it seems that ladybugs are pretty harmless under most circumstances. Just don’t try to eat them!

Not All Ladybugs Are Girls

Some people assume that ladybugs are ladybugs because all of them are female. I guess they assume that reproduction occurs by parthogenesis or something. However, ladybugs did not get their common moniker because they possess any particular feminine traits. They are actually named after the Virgin Mary. Legend has it that farmers during the Middle Ages were having a horrible time with pests that were eating their crops, so they prayed to the Virgin Mary for an answer. Shortly after, a swarm of red beetles arrived and devoured the problem insects. They believed that the red color of the beetle’s shell represented the red cloak of the Virgin Mother, so they began calling them The Beetles Of Our Lady, which has understandably been shortened over time to ladybeetle or ladybug. So, there are both male and female ladybugs, and they do reproduce sexually. In fact, that is one of the few ways to easily tell males and females apart.

Mating Ladybugs

During mating, the male will grasp and hold on to the elytra of the female. Copulation may take up to 2 hours, but the female can store the male’s sperm for up to 3 months before laying her eggs. She will usually lay them in groups of 10 - 40 on the underside of a leaf to keep it protected from rain. I was able to capture some video of a ladybug while she laid her eggs. It was very neat to watch as she neatly place each egg into the bundle. Without even looking, she was able to position her body so that the next egg fit perfectly. If you would like to see the process for yourself, check out the video below. Keep in mind that this process played out over about 20 minutes. There were times where she would sit completely still for several minutes between laying eggs, so I have edited the video for time.

Ladybug Laying Some Eggs

This female laid a total of 19 eggs before flying away. As you can see in the video, it is an exhausting process. It took her several attempts to fly away. Adult ladybugs will usually live for about a year. In that time, a female may lay up to 1000 eggs! But, we’ll talk more about them next time.