Stuff of nightmares? Meet the bootlace worm – super-long, super-elastic, and it fires toxic slime

Its mucus, which can kill crabs and cockroaches, could be the basis of new insecticides

It’s the shuddery stuff of nightmares for some, but for a select group who admire extending ladders, giraffes and the Odyssey, one of the longest animals in the world is bound to appeal.

This creature is not the blue whale, nor a lion’s mane jellyfish but the humble bootlace worm, Lineus longissimus, one of the most remarkable marine invertebrates of them all.

It’s invertebrate of the year again! From 3-12 August, every day we will profile one of the thousands of amazing invertebrates that our readers have nominated. And then, when you’ve heard about all of them, we’ll open the voting so you can choose your favourites. Don’t hesitate to get in touch with thoughts and ideas: email us at environment.desk@theguardian.com with Invertebrate in the subject line.