Across the animal kingdom, there are an incredible amount of different classifications of animals that vary wildly, from furry mammals to scaly reptiles.
Classifications are broken into two broad groups, vertebrates and invertebrates, that get gradually more specific. Today, we’re going to be looking at a phylum of invertebrates called arthropods. We’re going to delve into the unique characteristics they have, how they’ve evolved and how they survive today.
What is an arthropod?
An arthropod is a phylum of invertebrates identified by its exoskeleton, bi-lateral symmetry, jointed appendages, segmented bodies and specialised appendages. The scientific name for the family of arthropods is Arthropoda, which means “those with jointed feet”, which is why the examples of arthropods, including crustaceans, insects, and arachnids, are so broad.
The arthropod phylum of animals covers a wide range of animals, which is why they’re such a fascinating group of animals to explore in this blog.
The types of arthropods
Within a broad group of animals like arthropods, there are four main types:
- Arachnids: This includes spiders, scorpions, mites and ticks. Most arachnids have a segmented body with two parts and 8 legs.
- Crustaceans: There are 5 different types of crustaceans, but the most commonly known species include crabs, lobsters, crayfish, shrimp and barnacles. They have an exoskeleton, as well as a hard shell, which is the same material as arachnids and a tortoise’s shell.
- Insects: Insects are the largest family of arthropods – in fact, they are the most diverse group of animals in the world. It includes the likes of butterflies and moths, beetles and flies.
- Myriapods: Myriapods refer to species like millipedes and centipedes, characterised by many pairs of legs.
This variety shows just how far these animals have diverged from each other over the millions of years that they’ve been evolving.
The evolution of arthropods
The history of arthropods is a long and interesting one, dating back 500 million years – but we’ll give you the shorter version!
The earliest fossils of arthropods that have been discovered go back to the Cambrian period almost 500 million years, an astonishing length of time, especially when you consider that humans have only existed for about 7 million years. The Cambrian period is known for its significance in the emergence of invertebrates and fish appearing for the first time. Some of the first fossils include trilobites and crustaceans.
Arthropods have survived million of years because of their ability to adapt, making them one of the most successful groups of animals in evolution. They are found all over the world, in every habitat you can think of!
Arthropods you can see at Hastings Aquarium
You can see some of these fascinating members of Arthropoda for yourself, right here at Hastings Aquarium. Here are just some of the species you’ll find.
Asian forest scorpion
Also known as the Malaysian forest scorpion, this species (Heterometrus spinifer) is a stocky, black scorpion commonly found living under rocks and logs. It is venomous and can grow up to 12cm in length.
Sun beetle
The sun beetle (Amara aenea) is a type of beetle that is named for their activity during the day, which is unusual for beetles but is great for aquarium visitors who don’t want to wait until after dark! In the wild, they can be found in West and Central Africa feeding on fruits and wood.
Giant African millipede
As the name would suggest, these millipedes are named for their relative size compared to other millipedes. The giant African millipede (Archispirostreptus gigas) can naturally be found in the rainforests of subtropical Africa, chomping down on decaying matter that lived in their habitat.
Mexican red knee tarantula
This fascinating species of tarantula (Brachypelma hamorii) is a vulnerable species found across the forests and deserts of Mexico. It is a New World spider, which means it is a slower and more placid species than its Old World counterparts.
European lobster
The European lobster (Homarus gammarus), sometimes called the common lobster, is a species of lobster native to the Atlantic ocean, the Mediterranean Sea and parts of the Black Sea. These crustaceans are natural predators feeding on other crustaceans, fish, worms, and countless other sea creatures unlucky enough to find themselves in their powerful claws.
Arthropods are some of the most diverse animals on the planet, encompassing all corners of the earth and thriving wherever they find a home. From the giant African millipede to the European lobster, arthropods are fantastic animals to grab the attention and wonder of anyone who encounters them.
If you’d like to see some arthropods in the flesh, book your tickets to Hastings Aquarium now! Don’t forget to ask one of our team about the arthropods and perhaps you can share with them some of the facts that you’ve learned in this blog.