Name that thing

Invertebrate identification

If you are trying to identify, or want to know more about an invertebrate, but don't know where to start, and the list on the main page hasn't helped, then try below.

I've separated the invertebrates out by body shape, but do remember that this is just a rough and ready guide, and you won't find it in any academic textbook. Or you could try my new book availble from Amazon if it is an insect.

Smith, L. (2014). Characteristics of the insect orders. Amazon. Characteristics of the insect orders with drawings and photographs to help you understand the differences between the different types of insect, and identify which order an insect is in, as well as fast facts about each insect order, and links to web pages with more detailed information. Many orders have separate sections about the life cycle of the insect as well as its habitat requirements, and fossil history.

Things with 6 or more legs

• 6 legged are usually insects
• 8 legged are usually Chelicerata (spiders, scorpions etc.) or squid and octopus
• tiny things with 8 legs may be Tardigrada (water bears)
• things with more than 8 legs can be Crustacea (crabs, shrimps etc.), or Onychophora (velvet worms).

Things that look like worms

• If they are flat then they are probably Platyhelminthes (flatworms).
• Slugs can be wormlike.
• Worms with segments are usually Annelida (earthworms, freshwater worms, marine worms and leeches.
• Tiny little worms and larger parasitic worms are usually Nematodes.
• Long worms with a long proboscis (tongue) are Nemertea (ribbon worms).
• Some insects have worm-like larvae.
• Then there are all the rarer kinds of wormy things, Chaetognatha (marine arrow worms), Pentastomida (parasitic tongue worms), Nematomorpha (hair worms), Gastrotricha (tiny hairy worms), Mesozoa (tiny marine worms), Gnathostomulida (miniscule marine worms that have jaws), Pogonophora (deep-sea marine worms), Loricifera (tiny, rare marine worms with a spiny mouth), Acanthocephala (spiny-headed parasitic worms), Kinorhynca (miniscule spiny-headed marine worms), Hemichordata (marine worms sometimes colonial in tubes), Echiura (spoon worms, really weird marine worms), Sipuncula (marine worms shaped a little like a peanut), Phoronida (horseshoe-shaped marine worms with many tentacles around the mouth), Priapulida (marine worms with a large, retractable head).

Things that have a shell

• Mollusca (snails, clams, nautilus, etc.), Horseshoe crabs, Crustacea (crabs, shrimp etc.)
• Brachiopoda (lamp shells)
• Echinodermata (urchins, star fish etc.).

Things that have a radial body pattern

• Echinodermata (urchins, star fish etc.)
• Cnidaria (jelly fish, corals, anemones etc.)
• Ctenophora (comb jellies).

Tiny things in water

• Crustacea - these can have tiny larvae that look nothing like the adult.

Fish-like

• Chordata (lancelets)

Tadpole-like

• Chordata (sea squirts)

Things that don't fit in anywhere else

• Sponges (tiny animals that can form large colonies)
• Bryozoa (moss animals - tiny, colonial and sometimes mistaken for sponges)
• Entoprocta (tiny, colonial, aquatic and rare)
• Rotifera (tiny, mainly freshwater or moist habitats, common, but usually overlooked)
• Placozoa (tiny, marine, rare and little is known about them)

If you are still none the wiser, take a photograph of it, and put it back where you found it so that it can get on with its life. Write down where you found it and what it was doing, and the date, and time of day. In fact anything you can. One day you may come across some information that leads you to an identification of the thing, or just browse around in this website, you may get lucky, and you will see just how weird and fascinating life is.

Main invertebrate page