Are Lobsters Bugs Of The Sea?

Lobsters and bugs are very similar in their appearance. They especially reassemble one of the least liked bugs – a cockroach. Therefore, if you’ve ever wondered if lobsters are actual bugs, in this blog post, we’ll talk all about it. Let’s begin with a quick answer:

Lobsters aren’t bugs, but they are related as they belong to the same phylum Arthropoda. Nevertheless, “bugs” are insects that belong to the subphylum called Hexapoda and lobsters belong to Crustacea.

However, this certainly doesn’t tell the whole story. Below I’ll explain the main differences and similarities between lobsters and bugs. Furthermore, I’ll explain more about what animal lobsters are. Read on!

The differences between lobsters and bugs


Even though lobsters and bugs belong to the same phylum, they do have distinct features making them unique and assigned to different classes. Insects (or bugs) belong to the Insecta class, which includes mosquitos, beetles, ants, bees, cockroaches, and more. Lobsters belong to the class called Crustacea, which includes crabs, crayfish, shrimp, prawns, and more.

Classification of phylum Arthropoda and lobsters


Another difference between lobsters and bugs is their appendages. Bugs have three pairs of walking legs, but lobsters have five. Lobsters’ legs (called pereiopods) can be slightly modified, depending on the lobster’s species. For instance, clawed lobsters have the first pair of legs modified into large claws.


Since insects live outside of water and lobsters underwater, they can’t breathe the same way. Bugs breathe air through the holes (spiracles) on the outside of their bodies. They use them for gas exchange as they don’t have lungs.

Lobsters don’t have lungs either, and they breathe through their gills. Interestingly, lobsters can survive out of water for a certain amount of time if their lungs stay moist. They can then absorb oxygen from the water, but they can’t absorb it directly from the air.


Another major difference between lobsters and bugs is their habitat. Insects are a very diverse group of animals that live in about every habitat on Earth, from sandy hot deserts to cold, snowy mountains. Some of them adapted to living in the water and are known as “Aquatic insects”. However, they still need to manage to get oxygen from the air as they can’t breathe in the water.

Lobsters are exclusively marine animals living only in saltwater. They adapted to different temperatures, and some species prefer the colder waters of North America, others warm, tropical waters of the Caribbean. They’re benthic, which means they live on the bottom of the ocean.

Body parts

Lobsters and bugs’ bodies are divided into different parts. Insects’ have tri-segmented bodies consisting of the head, thorax, and abdomen. The head contains the antennae, eyes, and mouthparts. The thorax is the middle part of their bodies where legs are attached and wings. The abdomen is the tail that is flexible and contains digestive and reproductive organs.

Lobsters’ body, we can divide into two parts: a cephalothorax and an abdomen. The cephalothorax is a fusion of the head and the thorax. It contains the antennae, eyes, mouthparts, and legs. The abdomen is a flexible tail that allows them to swim rapidly to escape predators.

The similarities between lobsters and bugs


The first biggest similarity between lobsters and bugs is that they belong to the same phylum called Arthropoda. Therefore, because of this classification, these animals are going to share similar features related to their appendages, skeleton, and more, and we’re going to discuss them below.


Lobsters and bugs have an exoskeleton (“shells”) which is the external skeleton that supports and protects the animals’ bodies. Interestingly lobsters and insects shed their exoskeleton in a process called molting. They do that in order to grow as their shell doesn’t expand. Adult lobsters molt once every year or every two years.


Another similarity is that lobsters and bugs have a pair of long antennae. They use them to smell or touch their surroundings to navigate. They’re located in front of their heads, and depending on the species, their length can differ. For instance, spiny, non-clawed lobsters have very long antennae that help them protect themselves from predators.


Bugs and lobsters have similar mouthparts that help them manipulate food, chew, and grind it. They have mandibles – strong, powerful jaws and maxillae – ‘pincers’. Depending on the insect or lobster species, they’ll slightly differ in appearance and function.


Interestingly, cannibalism has been documented in bugs and lobsters. There are many insects that prey on the same species, such as ladybugs, grasshoppers, and even some butterflies. Lobsters sometimes will also eat other lobsters.

However, this is not a very common behavior, and the main factors causing it are rising water temperatures, their rapid increase and reproduction, overfishing, and low availability of alternative prey. If you’re interested in reading more about it, read my other blog post: “Are Lobsters Cannibals? (Why?)”.

Active at night

As you may already know, many insects are more active at night than during the day, such as crickets or the ones that we like much less – bed bugs, cockroaches, or mosquitos. Lobsters are also more active at night, which means they’re nocturnal animals.

During the day, lobsters hide in their shelters for most of the time. You can often find them under rocks or inside the reef. They come out at night to hunt, and you can see them very often during a night dive if you’re a scuba diver.

Regeneration of lost limbs

Both bugs and lobsters can regenerate lost limbs. They can regrow their legs as they molt. Lobsters can regrow their claws, walking legs, and antennae already after the first molt. The new appendage will be smaller than the original one and will continue growing for a few months or years until reaching the normal size.

Other similarities

Despite the features I mentioned, there are more similarities between lobsters and bugs, such as their omnivorous diet, immune systems, compound eyes, and more. Even though lobsters and bugs are not the same animals, they are closely related and share common ancestors.

What animals are lobsters?

After we know that lobsters are not bugs, what animals are they?

Lobsters are marine crustaceans which is a large, diverse group of arthropods. This group consists of about 30,000 different species, such as shrimp, krill, crabs, barnacles, crayfish, fish lice, and more. They are four major families of lobsters:

  • the clawed lobster (Nephropidae),
  • the spiny lobster, also known as rock lobster (Palinuridae),
  • the slipper lobster, also known as Spanish lobster (Scyllaridea),
  • the furry, also known as coral lobster (Synaxidae).

Lobsters’ families differ in how their body is built, their habitat, and their behavior. Despite the difference between the first pair of legs – claws, they have a lot of other distinct features. There are differences in the morphological structures on the front of their shell (carapace), the structure of their appendages, the shape of the carapace, the length and shape of their antennae, and more.

All lobsters have paired appendages: first antennae, second antennae, mandibles, first maxillae, and second maxillae. Next, they have five pairs of walking legs (pereiopods). These legs are slightly modified, depending on the lobster’s family. For example, in clawed lobster species, the first pair of legs is modified into large claws.

These invertebrates inhabit the bottom of every ocean, and the water temperature they live differs depending on the species. In general, clawed lobsters prefer colder waters and are very common in the Atlantic Ocean, especially along the North Atlantic coast of North America.

The non-clawed species, such as spiny lobsters, prefer tropical waters. You can often encounter them in tropical and subtropical parts of the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico. They’re also found in the Mediterranean Sea, coastal waters of Southeast Asia, Australia, and South Africa.

Lobsters are incredibly interesting animals with fascinating life cycle and communication methods. They’re known to communicate by peeing at each other and sending chemicals that translate the smell into a message.

They can live more than 100 years and never stop growing. Lobsters are omnivorous, which means they eat both plants and animal matter. They mostly prey on fish, crabs, clams, mussels, and sea urchins.

You may also like:


Welcome to Bubbly Diver!
I’m glad to see you here. This blog is created for all marine creature lovers by a bubbly diver - me, Dori :)