Invertebrates
Invertebrates
A group of animals who do not have a backbone or spine, including insects, arachnids (spiders and scorpions), mollusks, worms, crabs, and more!
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Arthropods
Insects, Arachnids, Millipedes and Centipedes, & Crustaceans
Black Widow Spider
Latrodectus ssp.
- Black widows are a group of spiders with about 30 species that are found all over the world in temperate areas.
- This spider is often feared for its fangs and venomous bite, which is said to be more than 15 times more powerful than rattlesnake venom!
- Only adult females can harm humans with their venom, males and juveniles are harmless!
- Their venom is quick to kill flies, grasshoppers, and beetles, but is rarely deadly in humans
- Females have a large abdomen and the iconic red hourglass, while males are brown and much smaller!
- Like other spiders, black widows will make webs and wait for prey to get stuck!
- They get the name black "widow" because females have been known to kill their partner after mating.
Brazilian Salmon Bird-Eating Tarantula
Lasiodora parahybana
- Brazilian salmon bird-eating tarantulas are one of the largest species of tarantula that exists today.
- With legs outstretched, this spider is 10 inches wide.
- Their fangs can measure up to an inch in length, though their venom won't kill you.
- While birds are on the menu, this tarantula mostly feeds on other small animals, like lizards and frogs, and other invertebrates.
- Like all tarantulas, the venom and digestive fluid cause their prey to liquefy and their remains are sucked up by the spider.
Carpenter Bees
Xylocopa ssp.
- Carpenter bees are a group of about 500 species that live in many parts of the world!
- Carpenter bees can be black, yellow, or a combination and are primarily solitary.
- Instead of creating a hive, carpenter bees are burrowers and will use their strong jaws to scrape and chew through pieces of dead wood. This is why they're called "carpenter" bees!
- Each burrow is a long, circular hole with just one entrance that the female will use to lay her giant eggs.
- Though larger and often more intimidating than other bees, they are "gentle giants" and rarely become aggressive.
- Carpenter bees often fall prey to woodpeckers who can break into their burrow.
- Carpenter bees are important pollinators!
Centipedes
Class: Chilopoda
- There are several thousand species of centipedes, many of which are not described yet.
- Unlike millipedes, centipedes are venomous carnivores that use their venom to hunt for insects and other small animals and to defend themselves from predators.
- Centipedes only have one pair of legs per segment, unlike a millipede which has two.
- Depending on the species, centipedes can have more than 150 pairs of legs!
- Unlike a millipede, centipedes are often flat and their legs go out to the side instead of staying underneath their bodies.
- Their last set of legs often resemble their antennae, which is thought to confuse predators.
- Their front legs are often used as shovels to dig for food and shelter.
Common Blue Butterfly
Polyommatus icarus
- Common blue butterflies are found throughout northern Africa, Europe, and Asia in open areas.
- They are active during the summer months when flowers are blooming and nectar is available.
- Males have a bright blue wing with a black and white border while females have a brown dusting on their wings with a variety of spots.
- Depending on the region, some common blue butterflies will lay two sets of eggs.
- Common blue butterflies are threatened by habitat loss, mainly the loss of their host plants which are a variety of legumes.
- These butterflies have been introduced into eastern Canada.
- A group of butterflies is called a kaleidoscope!
Dock Bug
Coreus marginatus
- Dock bugs are a species of leaf-footed bugs native to Europe, Asia, and Africa.
- They are named after their favorite meal, docks and sorrels (a genus of woody plant), not for their love of boating.
- They will also feed on other species of leafy greens, along with fruits.
- They have wide, flat backs that are brown in color and help them camouflage in woody areas.
- They have scent glands on their backs that unleash a harsh, foul-smelling secretion when threatened.
Giant African Millipede
Archispirostreptus gigas
- Giant African millipedes are the largest species of millipede in the world, reaching lengths of nearly one foot in length!
- Though their name implies they have one thousand legs, the giant African millipede only has 150-250 legs!
- Millipedes, like earthworms, are decomposers and will deposit nutrients in the soil as they eat decaying plant matter.
- When threatened, these millipedes will excrete a nasty liquid to deter anything birds, frogs, or small mammals that may want to eat them.
- As millipedes grow, they develop new sections that each contain two new sets of legs!
Hermit Crab
Superfamily: Paguroidea
- About 800 species of hermit crabs are found in a variety of habitats from tropical coasts to the deep ocean.
- The arthropod species in the world is a type of hermit crab! The coconut crab weighs up to 9-lbs and reaches more than 3-ft wide with its legs outstretched.
- Hermit crabs carry snail shells for protection. When threatened they can pull their bodies entirely inside the shell!
- Hermit crabs have a long, curved abdomen which they use to grab onto their shells.
- As hermit crabs grow, they must find bigger shells.
- Some hermit crabs have a symbiotic relationship with sea anemones! The anemone will attach to their shell and eat the crab's leftovers and the hermit crab is protected by the anemones stinging cells.
- Like true crabs, they can breathe underwater with gills and can breathe on land as long as their gills stay damp!
Katydid
Family: Tettigoniidae
- More than 6,000 species of insects are considered katydids, also known as long-horned grasshoppers.
- They are found on every continent except Antarctica in both dry and tropical regions.
- Most katydids have very efficient camouflage to blend in with and mimicking leaves.
- Katydids found in tropical regions are usually larger due to more plentiful resources.
- Katydids are named for their call that sounds like "kate-eee-did" that they produce by rubbing their wings and legs together.
- While most katydid species have wings, they are usually poor fliers and some species can't fly at all.
Ladybug
Family: Coccinellidae
- They're more than just one bug! In fact, ladybugs are a family of tiny beetles with more than 5,000 species.
- Ladybugs are sometimes called ladybirds or lady beetles.
- Many species of ladybug are carnivorous and eat other bugs that are harmful to crops, making them very helpful for humans.
- Scientists predict a single ladybug can eat 5,000 insects in its roughly one-year lifespan.
- While we usually picture ladybugs red with black spots, they can be many different colors and some even have stripes!
- A ladybug's bright color and spots are thought to warn predators of the foul liquid they can produce when threatened.
Large Milkweed Bug
Oncopeltus fasciatus
- Large milkweed bugs have a huge range throughout North America into Central America.
- Because of their huge range, these bugs can be very different sizes and have different behaviors based on where they are!
- They are named for their tendency to be found in large groups eating milkweed plants.
- Milkweed bugs will lay their eggs between the pods of milkweed plants.
- Milkweed bugs produce more offspring when they live in warm, tropical regions.
- In some areas, milkweed bugs are regarded as a nuisance because they will destroy milkweed crops.
Madagascar Hissing Cockroach
Gromphadorhina portentosa
- Madagascar hissing cockroaches are one of about 4,600 species of cockroaches.
- These rainforest-dwelling roaches are only found on the African island of Madagascar.
- Unlike the cockroaches you may see lurking around your home, these cockroaches do not have wings!
- They are named for the hissing sound produced when threatened.
- While many think this sound comes from their mouth, they actually create the noise by compressing the air from their body through tiny holes called spiracles that line each side of their body.
- These roaches also have a mutualistic relationship with small mites that live on their bodies. The mites help keep the cockroaches clean and the mites get an easy meal.
- Males have large bumps on their heads that they will ram into other males when competing for females.
Mantis
Order: Mantodea
- Mantises, or praying mantises, are an insect with more than 2,000 species!
- They get the "praying" part of their name because of their long, folded arms which they often hold upright in a praying position.
- Their long arms are covered in spines that help them grasp onto prey.
- Many species of mantis have wings, though not all of them can fly.
- Mantises primarily move around by walking and climbing.
- Female mantises have been known to eat their mates after breeding to stock up on nutrients.
- The Brunner's mantis, found in the southern US, reproduces through parthenogenesis, meaning the females reproduce without ever having mated; only females exist!
Monarch Butterfly
Danaus plexippus
- Monarch butterflies are one of about 750 species of butterflies native to the United States.
- Monarch eggs are laid on milkweed plants, which become the host plant that the caterpillars feed on when they hatch!
- Some monarchs migrate thousands of miles to California and Mexico during the winter and then fly home in the spring.
- They are the only species of butterfly to make a two-way migration like a bird!
- While they only eat the leaves of milkweed plants as caterpillars, they drink the nectar of many different plant species as adults.
- Monarchs are a large butterfly with a wingspan of more than 4-inches.
Robber Fly
Family: Asilidae
- Also known as the assassin fly, robber flies hunt by catching their flying prey mid-flight.
- There are more than 7,000 known species of robber flies that live in almost every type of ecosystem.
- Some species of robber flies are black or orange, while others have yellow and black stripes like a bee.
- Robber flies are incredible predators and can catch bees, dragonflies, butterflies, and other large insects with ease.
- Once they catch their prey, they inject them with paralyzing saliva.
- Females are known to be very selective of their mates and will often reject their advances and eat them instead.
Vinegaroon
Order: Thelyphonida
- More than 100 species of vinegaroons have been identified around the world.
- Vinegaroons are also known as whip scorpions!
- Though they are not true scorpions, their size and pinches make them look very similar!
- Instead of having a stinger, vinegaroons have a long, thin tail that sprays a liquid containing mainly acetic acid, or vinegar.
- They are an arachnid, like spiders and true scorpions, which have 8 legs and lack antennae.
- Vinegaroons are carnivores and commonly prey on a variety of insects and even other arachnids!
Weevils
Superfamily: Curculionoidea
- There are more than 90,000 known species of weevils found all around the world.
- Weevils are herbivores and often considered pests due to their ability to damage crops.
- Different species are known for eating stored grains and cotton.
- Some weevil species are unleashed to control invasive plant species with their incredible appetite.
- Their long snout allows them to chew, unlike most other insects who have to "drink" their food through a proboscis.
- Some weevil species have snouts as long as their bodies.
Cnidarians
Corals, Jellies, & Anemones
Coral
- Corals are a group of about 6,000 species that grow in shallow, tropical ocean waters.
- Known as the rainforest of the sea, coral reefs provide home and shelter to thousands of species.
- Corals are made of tiny polyps, which are small, tube-like animals that are related to jellyfish and anemones and usually have tentacles.
- Once corals start growing somewhere, they stay there for their whole lives.
- Some have stinging cells that can zap and catch small animals, but most rely on a type of algae called zooxanthellae for food.
- Zooxanthellae live within the polyps and provide them with nutrients while the polyp provides the algae a protected space to live.
Moon Jellies
Aurelia ssp.
- There are thought to be more than 10 species of moon jellies that all look very similar.
- Scientists aren't exactly sure how many species exist because the deep ocean is not greatly studied!
- This group of jellies has a wider range than any other jelly.
- They are typically translucent, or see-through, but can take on the color of what they eat.
- Moon jellies have weak venom which only causes minor stinging in humans.
- Jellies are actually a type of zooplankton that are moved around by ocean currents!
Molluscs
Octopus
Order: Octopoda
- There are roughly 300 species of octopuses.
- They are a type of mollusk and are closely related to squids, snails, and clams.
- The smallest species of octopus is smaller than an inch long while the largest has measured 30-feet!
- They have 8 arms surrounding their beak and mouth which they use to grab prey like crabs, fish, and snails.
- They use a funnel, or siphon, to pumps water for breathing and to propel them forward.
- Octopuses have the incredible ability to change color to frighten away predators or camouflage into their surroundings.
- Octopuses inject venomous saliva into their prey which affects the nervous system. Only one species is deadly to humans.
Roman Snail
Helix pomatia
- Roman snails, also known as burgundy snails, are land snails found throughout parts of Europe.
- Like all snails, they are closely related to slugs and in the same phylum as octopuses.
- They are a relatively large snail with a shell measuring up to 2 inches in length!
- Roman snails live in many different habitats, like forests and shrublands.
- These snails are hermaphrodites, meaning they have both male and female reproductive organs.
- This is the type of snail commonly used in escargot.
Sea Slugs
Order: Nudibranchs
- Most species of sea slugs are gastropods, meaning they are closely related to snails.
- Scientists think that over time and many generations, sea slugs evolved to lose their shells.
- Many sea slugs have shells in their larval phase.
- Sea slugs are often brightly colored, which scientists think is a way to warn predators of their poor taste or toxicity.
- Like all gastropods, sea slugs have tiny, sharp teeth that help them scrape plant matter off of rocks.
- The two antennae-like tentacles on their head are used for smell and often have structures on their back that act as gills.
Miscellaneous
Earthworms
Order: Opisthopora
- Earthworms are a group of large worms that consists of more than 1,500 species.
- While earthworms may not be the most beautiful, they are very important in many ecosystems!
- Earthworms are decomposers, or detritivores, meaning they feed on dead organic or plant material and return nutrients to the soil!
- Ecosystems depend on decomposers to clean up dead matter and create healthy soil that plants can use to grow!
- The digestive system of an earthworm runs the whole length of its body.
- Earthworms have no eyes or ears but can sense if the environment is light or dark and can "hear" using vibrations in the soil.
Sea Urchins
Class: Echinoidea
- There are more than 900 species of sea urchins, which are close relatives of sea stars and brittle stars.
- Sea urchins live in many marine ecosystems, from shallow, tropical waters to the deep ocean.
- Urchins have a round mouth with 5 teeth located directly underneath their bodies.
- Sea urchins use their long, pointy spines to move around and deter predators.
- Like sea stars, sea urchins have tube feet which they use to stick to objects and to taste.
- While they don't have eyes or eye spots like a sea star, they are nocturnal and avoid sunlight during the daytime.
- Sea urchins often live in large groups and can damage ecosystems by over-consuming vegetation.
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