Types of Worms

Types of Worms

Wriggly, squishy, crawling - ugh! I am not overtly fond of worms but my curiosity lead me to do some research about the types of worms and their peculiarities.
BiologyWise Staff
Like I said, I am not overtly fond of worms. In fact, earlier I used to be grossed out by worms to such an extent than I would throw up every time I saw one! One day, a friend of mine was doing some biology project for her mid terms and she showed me a jar full of earthworms she had herself dug up from the grounds of her dad's sprawling farmhouse. Yikes! I still remember the sight - scores of worms wriggling against each other, twisting, turning and locking each other into serpentine embraces! For an instance, I could visualize how Medusa's hairdo must have looked to Perseus when he first set his eyes on the mythical Gorgon! Anyway, that day, Amy (my buddy) told me of the many different types of worms that exist in Earth's biosphere and how they differ from, and are similar to, each other.

That day, I realized a profound truth - curiosity takes the form of fascination when it comes to things you like but it assumes obsessive proportions when it comes to things that repel you! Don't believe me? How else would you explain the huge fan following of action, slasher and sci-fi movies showing gory scenes and gooey, slimy and disgusting looking creatures? Well, now that I've made my point, let me give you a tour of the various different types of worms that I learned of from Amy.

What are the Different Kinds of Worms?

The word worm is used to define those invertebrate organisms that have an elongated, mostly cylindrical body and no legs. Although sometimes certain insect larvae are also known as worms due to their worm-like appearances at the larval stage, they cannot be classified under true worms. As such, the organisms who can, more or less, be justifiably included under the purview of worms include annelids, nematodes, flatworms, nemertean worms and Chaetognatha worms. Many of these are parasitic and are common worms in humans and other mammals.

Annelids are segmented invertebrates whose elongated bodies are made up of ring like segments. The most amazing thing about this type of body structure is that each of these segments contain the same set of organs! Leeches, earthworms and ragworms are the most common examples of annelids. Although annelids like leeches prey on the blood of mammals, worms like earthworms do us a favor by performing various important ecological functions.

Nematodes are worms that have a perfectly cylindrical, elongated and unsegmented body structure. Commonly known as roundworms, this phylum includes an extensively wide array of different organisms, most of who are unrelated to each other. Most roundworms are parasitic and some of the most common varieties of worms in dogs and humans tend to belong to this category. Hookworm, pinworm and whipworm are common types of roundworms that are parasitic in nature.

Flatworms are invertebrates that are neither segmented nor cylindrical. The name itself suggests the shape of the bodies of these organisms, which appear flattened and have a very simple bilaterian structure. Common examples are tapeworms, planarians and monogenea. Most flatworms are parasitic in nature. Read more on different types of flatworms.

Nemertean worms are also known as ribbon worms or proboscis worms and are mostly water-dwelling, with very few species being entirely terrestrial. Among the aquatic species, the majority are found in marine environment and very few live in fresh water. These worms have a long, slender, unsegmented body with no prominent head and a slightly wider anterior.

Chaetognatha worms are also known as arrow worms and are characterized by their translucent, arrow shaped bodies. These worms are marine dwellers and can be found attached to rocks, algae and plankton. In fact, they comprise a major part of most plankton found in all seas of the world. These worms are predatory in nature.

Accounts of various fantastical worms can be found in the mythologies of many cultures. Dragons, for instance, and other mythical serpents were often referred to as worms, wurm or wyrm. The titular creature in the English fairy tale, The Laidly Worm of Spindleston Heugh, is a prominent example. Also, the 1988 film The Lair of the White Worm, starring Amanda Donohoe and Hugh Grant, also depicts a serpentine creature whose inspiration is drawn very closely from the Lambton Worm legend.
Flatworm Underwater
Worm on White Background