Hello again! Hopefully I'm back to posting somewhat regularly! It's still very much too cold to see much of anything outside up here right now but I just got another confirmation on iNaturalist which brings my count of lady beetles to 3!
You've probably heard of the members of Coccinellidae referred to as lady bugs. Entomologists now use ladybird beetle/lady beetle now to avoid confusion with true bugs which lady beetles are not.
I wanted to take a minute to talk about the name because there was a surprising amount of information on it.
Coccinellidae is derived from the Latin word coccineus meaning scarlet. The lady in both lady beetle (USA) and ladybird (Britain) refers to mother Mary. As such, in Britain they became known as "Our Lady's Birds". Mary was often depicted wearing a red cloak in early art and the seven spots of the species Coccinella septempunctata (the most common in Europe) were meant to represent her seven joys and seven sorrows. That was the most information I've read on a name since starting this blog, interesting!
As you know if you've come across one, they are oval beetles with a domed back and flat belly. Many species have coloration that warn predators that they taste bad (conspicuous aposematic) such as red with black spots or stripes. Some species have stripes or checkered patterns!
Note: Pictured above is the American Three-Banded Lady Beetle (Coccinella trifasciata perplexa). It's the only one I've seen personally that had bands instead of spots!
Spots vary in size, shape, and number. As mentioned above coloration is usually a warning but some species use it for camouflage or even to regulate heat. Furthermore, several species may have polymorphism and change color between seasons! I was astounded that there was so much to learn about a beetle that I see all the time in the warm months.
Adult females tend to be a little larger than the males. All have large compound eyes and clubbed antennae with seven to eleven segments. I'm just recently learning how many types of insects can be identified by how many segments their antennae have! They also have powerful mandibles which have pairs of "teeth" that face each other.
Another intriguing thing about them is the way they defend themselves. A 2015 study of five ladybird species found that their color honestly signalled their toxicity which means they weren't just pretending, their warning is pretty trustworthy! They also found that species that stand out from their environment more were the ones that were usually the more toxic.
How are they toxic? Turns out their blood contain a bunch of chemicals and alkaloids that make them toxic and stinky. Coccinellids can produce at least 50 types of alkaloids! You won't have to tell me twice not to take a bite of one of these little ladies.
They also do something I've never heard of before: reflex bleeding. Before they're even harmed they exude drops from their knee joints that give predators a sneak peek of their toxic and bitter fluids. This is really important for their pupa which cannot move but helpful for all stages.
Note: This is a pupa of the Asian Lady Beetle (Harmonia axyridis).
Did you know that Coccinellidae are found on every continent except Antarctica? There are more than 6,000 described species and are found in many different habitats. They can live both on the ground and in trees. Some specialize on certain plants depending on their diet. Some even live in extreme environments like high mountains, deserts, and cold regions.
I never knew such small creatures migrated but they sure can! Depending on the conditions where they live, they migrate long distances to hibernation and breeding sites. They even have been thought to be drawn to recognizable landmarks! Temperate species hibernate or undergo a period of suspended development over the winter while tropical species are dormant during the dry season. If a location is too crowded some will leave but they stay as long as there are enough prey species to feed on.
Most coccinellid species are carnivorous predators. They usually eat aphids and scale insects but other species are known to eat plants and fungi!
Note: Pictured above is the Twenty-spotted Lady Beetle (Psyllobora vigintimaculata). It is not a predator. Instead, it eats powdery mildew on crops like pumpkin and zucchini.
Aphid-eaters tend to be more generalist in nature because of their insatiable appetite. They can also multiply quickly and switch to other prey when their aphids become scarce. Predators of scale insects on the other hand tend to be less voracious and are slower breeders and take their time with development.
One thing that predators of aphids have to worry about that predators of scale insects don't are ants! Ants tend to use aphids for their honeydew, kind of like how we use cows for milk, so the ants protect them and dispose of coccinellid eggs near their nests.
Speaking of eggs, many predatory species lay their eggs near colonies of prey so their babies have a food source when they emerge. Eggs tend to be bright yellow and close together. The number of eggs is dependent on species and ranges anywhere from tens to thousands in their lifetimes.
After the larvae hatch they immediately start eating, that includes their siblings that haven't hatched yet! Some species combat this by laying infertile eggs with the fertile ones in hopes that those will get eaten instead.
Note: I'm unsure of the species of this one but it is definitely a lady beetle larvae. Seek seems to think it's Harmonia so I really wouldn't be surprised if it was the Asian Lady Beetle (Harmonia axyridis) as there are many in my area.
Coccinellids are promiscuous breeders which means they reproduce in the spring and summer in temperate regions and during the wet season in tropical regions. In some species females seem to choose their partners based on size and color preferences. Did you know insects can get sexually transmitted infections? I didn't! Apparently the coccinellids are so promiscuous that they are often infected, yikes!
There are apparently many uses for coccinellids going all the way back to 1814 in England in pest control! Because of this, many species have been introduced outside their normal range and are considered beneficial insects! Scale insect-eating coccinellids have been more successful than aphid predators. Out of 155 deliberate introductions for aphid control in the year 2000, only one was deemed to be "substantially successful". This abysmal score is because they're so fast breeding, eat so much, and easily switch prey which makes them hard to control.
Unfortunately they are also pests. Some species are known to swarm into buildings from nearby fields and forests. Once in the summer of 1976 in the UK, after an unusually long period of hot and dry weather, an increase in aphid population was followed by a "plague" of the native Coccinella septempunctata. There were many reports of people being bitten as the elusive aphids began to dwindle. A not so fun fact also tells us that as few as 1.3 to 1.5 coccinellids per 2.2lbs of grapes can affect wine quality.
There are many threats to coccinellids today: climate change, agriculture, urbanization, and invasive species.
Note: This is the Asian Lady Beetle (Harmonia axyridis) and it's invasive where I live in North America. They outcompete the native species and eat their eggs to the point that if you see a lady beetle, it's probably one of these.
Their biodiversity will be affected by rising temperatures and heat fluctuations. Climate change might also lead to smaller larvae and require more energy, metabolic needs, and interspecies predation as prey are affected. Agriculture and urbanization threaten them because of habitat loss and pesticide use.
Conservationists in the IUCN SSC Ladybird Specialist Group have suggested several measures for protecting them including citizen science and education programs, habitat preservation and restoration, prevention of the spread of invasive species, and a global monitoring program.
This has become quite the lengthy post, maybe the longest one yet! But, there was so much information and I didn't want to leave any of the interesting stuff out. I have one more section I'd like to address: their role in culture.
They're associated with luck, love, fertility, and prophecy. They've been said to predict the future, particularly weather conditions and how crops will do in a given year. In Christianity, coccinellids have been called literal gatekeepers of Heaven. The Swedish name for them, Himmelska nycla, means Keys of Heaven. Jews have called them Cow of Moses Our Teacher. The Cherokee believe them to be the "Great Beloved Woman". This was because of their highest ranking woman in their government who would be painted in the lady beetle colors and patterns for ceremonies! Finally, ladybird is an affectionate term for a loved one!
As always, I hope you learned a lot because I sure did! I've always loved lady beetles. I used to see them when I was little in my mom's old house. They liked to hang out on the windowsills, I have a vague memory of one biting me and me being scared of them for a time. No need to fear them though! They can be pests but I think they're mostly beneficial. I always smile when I see one. Until next time.
Yours,
Jade
