Wednesday 7 August 2013

Ship-timber Beetle

Image: Michael Whitehead
Beetles don't get much weirder than this!

Ship-timber Beetles are a mere 37 species in the family Lymexlidae, all about 1 or 2 cm (0.2-0.8 in) long.

As the name suggests, they HATE sailors and love to sink ships! Probably because of those stupid uniforms and funny dances.

Image: Udo Schmidt
Hylecoetus dermestoides
Oh, fine, you got me. They really don't have any great feelings toward sailors, or any other occupation or hobby for that matter. They're extremely tolerant like that.

What they like is wood. Sometimes living wood in fine, upstanding trees, other times dead wood in fallen trees or timber they find lying about the place. And if that timber happens to be piled up into the shape of a house or a ship, for example, that'll do perfectly fine too.

Image: Stanislav Krejčík
Elateroides dermestoides
These are wood-boring beetles. It's the larvae who spend their time tunnelling through wood, but even the adults have a long, narrow shape perfect for the little mine shafts. That may just be so they can get out after they pupate.

Image: Vijay Anand Ismavel
Some Ship-timber Beetles seem a little too long for their own good. Their abdomen extends way past their rather inadequate wing cases.

Image: LC Shih
Atractocerus monticola
And then you have the deeply peculiar members of the genus Atractocerus...

Video: Quaoar Power

Their wing cases are minuscule and leave their wings completely exposed as they lie unfolded along their back. They have gigantic eyes, rather like a wasp or horsefly, as opposed to the little ant-like things other Ship-timber Beetles have. It's quite possible that some of those other ones don't feed at all as adults.

Image: LC Shih
Atractocerus must be using those giant peepers for something! Maybe spotting prey to feast on. Or sailors. Little is known about them, though.

At least some Ship-timber Beetles have developed a very special relationship with fungus. Not "special" like athlete's foot or sexually transmitted infections, but special like the yeast we make bread and beer out of.

Can man live on bread and beer alone? Hmmm...

Image: Ondřej Zicha
Lymexylon navale
Females lay their eggs via the ovipositor, and right near it is a pouch full of spores from a fungus called Endomyces hylecoeti. This stuff coats her eggs as she lays them. The larvae then collect some of them when they hatch before they commence wood-boring.

Image: Stanislaw Kinelski,
Elateroides dermestoides larva or Large Timberworm
Now, everywhere the larvae goes fungal spores are left clinging to the tunnel wall. The spores, er... hatch? Sprout? They do what they do! The fungus grows and the larvae eats it. So Ship-timber Beetles don't actually feed on wood, they eat the fungus their mother brought for them.

The larvae continually clear their tunnel of sawdust and droppings, ensuring their fungus friends get the fresh air they need to survive. And then they eat their fungus friends, because that's what friendship is all about.


  1. They sure are! Especially if you're a pile of wood! Or sailing on one.

  2. That fungus relationship is so amazing, hard to believe that it actually happens

  3. I know what you mean! It's actually not uncommon among wood boring beetles!

  4. I catched one and it laid eggs. Now I have the larva but nothing to feed them with. Can I just feed the with yeast?

  5. Difficult to say. They might require a very specific species of fungus.