I've got a mantis.. Beware!
 

Adam, it will cover in the hole with bits of rock and sand. Mine doesn't like his front door open. He drilled right thru the rock and made a back door and comes and goes from there. If I turn the rock around, he fills in the backdoor and uses the old front door again! Tou'll probably find that he opens it in the morning again. Give him a bit of prawn or something with some tweezers. He'll love ya for it!
It is most likely a Gonodactylus species.
Go here for more info.. http://www.blueboard.com/mantis/

I've got a mantis.. Beware!
 

I recently purchased about 10 pounds of Bali live rock from Big Al's (I guess it's in Coquitlam?).. Very very nice rock! Well today I was peeking in my curing tank with my flashlight and noticed two little eyes poking out of a hole in the live rock.. Upon further inspection I could see all the typical features of a mantis shrimp.. So anyway, I just wanted to warn anyone who has or is planning on buying this rock.. Check it very carefully before adding it to an established system.. I'm sure glad I decided to set up this curing tank.. Now it's gonna be my mantis tank! I'm trying to get a good pic.

I've got a mantis.. Beware!
 

Reef_Raf is right. the smaller mantis's any ways. i find that my 4" O. scyllarus doesnt do this though. she (the mantis) will keep the den openings open. every time i walk past the tank shes in she will poke her head out of the opening and check to see if im going to feed her.

i also notice that larger specimens no longer burrow into live rock. they will find some crevice in between live rocks and use shells Etc. to construct a den out of.

reefburnaby is right they can do A LOT of damage to a reef tank. if you plan on keeping one for long term you should put the mantis in its own tank. most ppl here in the states use a elipse 6 or a ten gallon. my larger mantis is in a 10g tank, which i plan on upgrading to a 30g tank.

ahhhh what fun it is keeping a Mantis

[ 22 October 2001: Message edited by: agilecrux ]

I've got a mantis.. Beware!
 

Brad you are right.. He opened up the hole again today.. I was planning on getting an eclipse tank for him.. probably just a 6 gallon.. I have a little peice of crap lee's skimmer he can have too.. Maybe I'll add a 28w pc and some shrooms or something..

I've got a mantis.. Beware!
 

I managed to get a couple pics of him now.. Pretty sad in these low light conditions though.. He's smaller then I thought.. only about 3/4 of an inch.. You can see some definate stomadipod traits anwyay..

http://livevictoria.com/limestone/reef/mantis02.jpg

http://livevictoria.com/limestone/reef/mantis01.jpg