Insect of the Week - Mystery Insect Revealed!

Remember this mystery insect from last week:

Photo by Alex Wild (www. alexanderwild.com)

The only hint given last week was that this little critter was, in fact, an insect (because it has three pairs of legs). No one had any good guesses - and I have to admit - this was a tough one!

So, now to reveal the mystery - drum roll please..... this little critter is a firefly (or lightning bug) larva! Who knew a firefly larva was so strange looking!

We all know that adult fireflies "light up" - they emit light that we enjoy watching on hot summer nights. For many of us, spotting and catching fireflies is one of our favorite summertime memories.

Fireflies use their lights to talk to each other. Adults emit light mostly to attract mates, but they may also use their light to defend their territory and keep predators away. In some firefly species, only one sex lights up. In most, however, both sexes emit light. Male fireflies flash their abdomens in species-specific patterns, hoping to attract the attention of a female hiding in the grass. An interested female will return the pattern, helping guide the male to her in the darkness. Firefly light patterns will vary in frequency and length, and are species-specific. In addition, the height at which they emit their light while in flight will vary depending on the species. Pretty cool, huh? One other interesting fact about fireflies - they are actually beetles!

Firefly larva (Photo by Jasja Dekker)

So, we all know adult fireflies emit lights, but did you know that firefly larvae also light up? But why do the larvae glow? What purpose does it serve? Light emitting serves a different function in larvae than it does in adults. It appears to be a warning signal to predators since many firefly larvae contain chemicals that are distasteful or toxic. 

Firefly larvae live on the ground, under bark, and in other moist places. They eat earthworms, snails and slugs. Larvae may also scavenge on certain small dead animals and other organic material. They have sickle-shaped mandibles with which they can inject a kind of chemical that paralyzes their prey and helps digest it.

Check out this amazing video below to see a firefly larva glowing:

http://www.myspace.com/video/quaoarlo/firefly-larva-of-thailand/24023925

Insect of the Week - What Am I?

Another mystery creature this week! Take a look at the photo below and take a guess at what type of critter this is. Here's a tidbit that might help narrow things down:  insects have just three pair of legs. So, this mystery insect is, in fact, an insect and not a creature closely related to an insect. The answer will be revealed next week!

Photo by Alex Wild, www.alexanderwild.com

Insect of the Week - What Am I?

This week's insect is a mystery! Take a look at the amazing images below by Alex Wild (http://www.alexanderwild.com) and see if you can figure out what the mystery insect is (all photos shown are the same type of insect). We'll have the answer in next week's "Insect of the Week" posting. Following the photos are a few hints!

The tube-like insect on the right is the insect in question!

Helpful Hints:

• These insects have complete metamorphosis.
• They taste, smell, and feel with the hairs that cover their bodies.
• These insects vomit on food before eating it, so as to soften the meal up.
• This insect may have sponging, lapping, or piercing mouthparts, depending on the species.
• They walk on smooth surfaces using sticky soft pads that act like glue.
• And here's the giveaway: This insect has only two wings as an adult; the hindwing has been reduced to small knobs, called halteres (see last image above).

Insect of the Week - The Antlion

Antlion larva

(Photo: Alex Wild, http://www.alexanderwild.com)

Antlions are quite fierce and scary looking. One look and you know you're dealing with a voracious predator (see photo above)! The antlion digs a pit in sand or other loose soil and hides beneath the sand at the bottom of the pit. When an ant or another small insect comes by, it falls into the pit where it slips to the bottom and is grabbed and made into a meal by the antlion. If the prey attempts to scramble up the walls of the pit, the antlion throws loose sand from below. This causes the sides of the pit to collapse, bringing the prey down into the bottom of the pit.

Check out this awesome video to see an antlion in action:  http://www.youtube.com/watch?v=7lYAWwMOCXE

Adult antlion
(Photo: Joseph Berger, Bugwood.org)

An antlion is actually the larval form of what will become a beautiful, dainty lacewing. The adult has two pairs of long, narrow, multi-veined wings, and a long, slender abdomen (see photo at right). Adult antlions look very similar to small dragonflies or damselflies, but are easily distinguished from these insects by their prominent, clubbed antennae (dragonflies and damselflies have very short, bristle-like antennae). Also, adult antlions are typically active in the evening, so they are normally not encountered as often. Lacewings are attracted to light so it is not uncommon, however, to see them around porch lights at night.

Antlions are commonly referred to as doodlebugs because they leave lines in the sand that resemble "scribbling" or "doodling" as they meander through the sand searching for the perfect place to make their pit. Check out the video below to see an antlion "doodling."

http://www.youtube.com/watch?v=exzPhd1abnw&feature=fvwrel

Antlion pits (Photo: Whitney Cranshaw, CSU)

You can easily observe antlion behavior in nature. If you ever run across an antlion pit (see photo above), you can use a small blade of grass to brush the sides of the pit. This will usually cause the antlion to flick sand up in the pit. You can also capture an antlion by carefully scooping out the entire pit (using your hand or a cup), being careful to dig deep and wide enough so the antlion isn't crushed. Pour the sand through a strainer until you see the exposed antlion. 

The antlion is a great insect to keep and observe in the classroom if you are willing to provide live insects for it to feed on. You can catch ants or other small insects to feed your antlion. You can also purchase wingless fruit flies online - they make a great food source for antlions. You can either collect an antlion as described above or you can buy them online. You'll need a small container with sand to house your antlion in. Provide your antlion live insects twice a day and lightly mist the container with water every other day. 

Insect of the Week - The Wheel Bug

Adult wheel bug

(Photo: Johnny N. Dell, Bugwood.org)

The wheel bug is an assassin in the insect world, literally. The wheel bug belongs in the Family Reduviidae, commonly referred to as assassin bugs, and for good reason! These insects are predators and pierce their prey (soft-bodied insects such as caterpillars, moths, aphids, small beetles etc.) with their beak-like mouthpart and inject a potent saliva. The saliva contains enzymes that quickly subdue the prey and then digest the tissues inside. The wheel bug then sucks this digested liquid from the prey as it shrivels up. What a way to go! Wheel bugs are not aggressive and will try to avoid contact, but can inflict a painful bite if aggravated or handled, so it's best to leave it alone if you run across one.

Wheel bug egg mass and hatched nymphs 

(Photo: Johnny N. Dell, Bugwood.org)

The wheel bug is one of the largest assassin bugs in NC; adults measure 1 - 1.25 inches in length. They are very distinct looking, sporting a large, gear-shaped half wheel on their thorax and a large, piercing beak tucked under the head.

In the fall, female wheel bugs lay masses of eggs by gluing them to bark or some other object. Tiny wheel bug nymphs hatch in April and May and begin to feed on aphids and other small insects. As nymphs develop they become larger and thus capable of attacking larger prey. When prey is scarce, wheel bugs feed on other wheel bugs, and female wheel bugs commonly feed on male wheel bugs after mating.

Check out the spectacular video below by Daniel R. Jusino, Rutgers University Entomology Department. It showcases the wheel bug and includes some amazing footage of nymphs hatching, molting, and feeding.

Insect of the Week - The Ladybug

Adult ladybird beetle
(Photo: Scott Bauer, USDA)

Since we've all heard the life cycle, habits, and problems with ladybugs ad nauseam, I thought it might be fun to write about fun facts about the beetles instead. For those of you that would like more information on the above aspects of these beetles, please see our fact sheet: http://insects.ncsu.edu/Other/goodpest/note107.html

Ladybugs aren't really bugs. 

In the entomology world, the term bug refers to insects in the Order Hemiptera. Ladybugs are beetles and belong to the Order Coleoptera. Us entomologists refer to ladybugs as ladybird beetles or lady beetles since they are not really bugs. But I won't mind if you still call them ladybugs. If you want to know what makes an insect a true bug, you can read more here: http://www.cals.ncsu.edu/course/ent425/compendium/hetero~1.html

Where did the name "ladybird" come from?

The most common species of lady beetle in Britain is the seven-spot ladybird beetle. This bright red ladybird has seven spots and is thought to have inspired the name ladybird. Lady, referring to the Virgin Mary (Our Lady), is seen wearing a red cloak in early paintings; the seven spots are symbolic of the seven joys and seven sorrows of Mary.

Lady beetle larva attacking aphids
(Photo: David Cappaert, Mich. State Univ.)

Immature lady beetles look like monsters and are voracious predators.Both the larval and adult forms of predatory ladybird beetle species feed on a wide variety of insects, including aphids, scale insects, and other insect larvae (including other lady beetle larvae). Both the adults and larvae actively hunt for prey in field crops, gardens, and ornamental trees and shrubs.

Do lady beetles get bigger as they get older?

No. Once an adult, it stays the same size for the rest of its life. Insects wear their skeleton on the outside; therefore, they must molt in order to grow. Insects with complete metamorphosis, including the lady beetle, do not molt as adults.

Ladybird beetles ooze blood from their leg joints when alarmed.A lady beetle's blood, referred to as hemolymph, is both toxic and smelly. When a ladybird beetle is startled, the blood seeps from its leg joints, leaving a stink and yellow stains behind. These secretions from the leg joints also taste bad and protect the beetles from being eaten from predators such as birds.

The lowdown on lady beetle spots.

Variations of spot patterns and colors of the
Asian mulit-colored lady beetle
(Photo: Bill Ree, Texas A&M Univ.)

The spots on a ladybird beetle do not tell its age. The sex of a lady beetle cannot be determined by the number of spots either. The spot patterns of the beetles vary widely from species to species. The number of spots and the color among ladybird beetles of the same species can vary greatly as well. The bright colors and spots of lady beetles warn predators that they taste yucky.

Can I keep a lady beetle as a temporary pet?

Sure! Keep your ladybird beetle in a bug box or terrarium-type container. Keep the container and foliage moist by gently misting the interior container with water using a spray bottle. You can feed your lady beetle moistened raisins or other sweet, non-acidic fruits. Or you may want to collect some aphids from ornamental shrubs and place them in the container for the beetle to eat. You can even watch the entire life cycle with a ladybird rearing kit (can be purchased online) where you get to watch the larvae grow and turn into adult ladybird beetles.

Wives tales and superstitions about lady beetles:

• The ladybird beetle is supposedly a luck-bringer. I was always told that it was a sign of good fortune if one landed on a person. The beetle must, however, be allowed to fly away on its own and not be brushed off. Supposedly, you can cause the lady beetle to fly away by singing a children's nursery rhyme, which goes like this:

Ladybird, ladybird, fly away home. 


Your house is on fire and your children are gone. 

All except one, and that's Little Anne.

For she has crept under the warming pan.

• If a ladybird beetle does lands on you and then flies away, then watch it carefully; the way it flies is the direction of your true love.

• If a ladybird beetle enters your house, a visitor will come (for folks dealing with large numbers of lady beetles invading their house this fall, this may or may not be good news!). 

• In northern Germany, it was believed that if the ladybird beetle had less than seven spots, then they would have a large harvest.

Insect of the Week - Carolina Mantid

Carolina mantid
(Photo: Patty Alder, NCSU)

Mantids are one of the most well-recognized groups of insects. One of the most distinctive features about mantids is their large, grasping front legs, which they use for grabbing and holding prey. Mantids have a very elongated prothorax and a triangular-shaped head, which they can turn in nearly all directions. The mantid is commonly called the praying mantis, which comes from the way it holds the front legs in "prayer-like" stance. They are sometimes mistakenly referred to as the "preying mantis" because they are predatory, feeding on a wide variety of other insects.

There are actually several species of mantids found in NC. The European mantid and the Chinese species were introduced in the northeast about 75 years ago as garden predators in hopes of controlling the native insect pest populations. The Carolina mantid is a native insect.

Carolina mantid egg case
(Photo: Jim Kalisch)

Carolina mantids overwinter as eggs. Females lay eggs in large masses in a frothy material that hardens into a protective shell, called an ootheca. The new mantids hatch in the spring and mature into adults over the summer.

Mantids are beneficial insects; they feed on other insects, some of which we consider pests. However, their overall effectiveness in pest management is small, especially compared to other insect predators, such lady beetles and green lacewings. This is due to their cannibalistic nature which limits the number of mantids in a particular area.

Rearing mantids for classroom projects

A glass jar set-up for rearing mantids
(Picture: Univ. of AZ)

Egg masses can be collected in the fall and brought into the classroom. Mantid egg cases and young mantids can also be purchased online. Because they are in a warm environment, the mantids may actually hatch as early as December once brought indoors. It's a good idea to have several small containers available because when they hatch, large numbers of very tiny mantids will suddenly appear. If they do not have fresh, live food available, they will eat each other until only one or a few mantids are left.

Small flying insects that are attracted to porch lights are a good source of food for the newly emerged mantids. As they get older and larger, they can be fed larger insects, such as crickets, which can be purchased from pet shops. Mantids do need water, which can be provided by gently misting the inside of the container once a week. Or place a small, wet sponge in the container that the mantid can collect water from.

For more information on rearing mantids, see this rearing sheet prepared by The Center for Insect Science Education Outreach, University of Arizona:  http://insected.arizona.edu/mantidrear.htm.