The Mole Crab Albunea symmysta at Bramston Beach North Queensland

I put in a lot of hours walking beaches for three very sound reasons.

Firstly beaches are relaxing places to walk and wind down, secondly the exercise is good for me and last but not least ...

... you just never know what you will find on a beach and the creature I am about to introduce you to is proof of the pudding.
Well there it is, Albunea symmysta in all its glory, but let’s rewind and start at the beginning as that is always a good place to start a story!

On the 12 June 2010 I went for a low tide walk along Bramston Beach in North Queensland which is only a few kilometres away from my home.

Here is a photo of Bramston Beach looking north towards the mouth of Blue Metal Creek.
As I said earlier the tide was low which always makes for an interesting beach walk.

Here is the view looking north.
Here is the view looking south towards Cooper Point which is the northernmost tip of the Ella Bay National Park.
I saw the usual wonderful things one can find at Bramston Beach on a low tide.

Sand dollars were present in the shallows.

Both alive
And dead.
Of course there were crabs to be found in the sand.
This one looks like a Moon crab Ashtoret lunaris with wicked spikes on the edges its shell!
As I was walking I saw what looked like a mouse covered in sand scurrying towards the water so I grabbed the mystery creature and gave it a rinse in the brine and saw a creature I have never encountered in my travels!
What I thought was a tail was in fact antennae.
From the rear and side it was obvious that this animal was made for digging!

Turning the animal over I could see it had no claws but instead it had strong hooked legs designed for digging.
After looking this unusual creature over I decided to let it go and released it at the waters edge where it commenced digging in ricky tik double quick!
Eventually all that could be seen of my armour plated discovery was its antennae waving in the current.
This is the bit where my scientist friends hit me over the head and ask why I didn’t whack it in a jar of alcohol and send it off to a museum…alas I’m getting soft in my old age and will leave the killing to property developers and beach drivers!

Upon returning home I sent photos off to all of my contacts who might know what this strange animal is and was soon rewarded with a reply from Dr Thomas Schlacher (A brilliant Queensland beach/coastal scientist) who suggested it was a Mole crab.

Not to be out done Dr Helen Larsen (another brilliant scientist with a passion for gobies) said the same thing and offered to look into it further.

Whilst all this was happening I was googling Mole crabs and most of the information I could find related to the genus Hippa.

I found an awesome video of American mole crabs filter feeding and here it is!

Finally Queensland Museum came to the rescue with a name for my mystery Mole crab; well to be a little more precise Dr Peter Davie Senior Curator (crustacea) came to the rescue.

Peter Said:

Dear Russell, Helen, et al.,

Your pictures are of one of the “mole” crabs, Albunea symmysta, in the family Albuneidae. These are not true crabs (Brachyura), but “Half-crabs” (Anomura) as they still have full abdomens and tail-fans. A bit more info below:

Albunea symmysta (Linnaeus, 1758)

Distribution: Northern Australia, Lord Howe Island; widespread tropical Indo-Pacific Oceans.

Ecology: benthic, sand bottom, sublittoral, burrowing; often in wash-zone on beaches around low tide mark.

ALBUNEIDAE Stimpson, 1858

Albuneids are relatively small, crab-like anomurans. Typically, like the closely related Hippidae, they burrow into sandy substrates. This habit means that they are rarely encountered unless being specifically targeted for collection, and thus have been poorly studied. They are mostly found in relatively shallow coastal waters, but range in depth down to 225 metres.

Regards,

Peter
P.J.F. Davie
Senior Curator (Crustacea)
Co-Editor (Aquatic Biodiversity), Memoirs of the Queensland Museum
Queensland Centre for Biodiversity

I would like to thank Queensland Museum for their help not only with this identification but for the assistance they have given freely over the last couple of years. Their staff are always enthusiastic and have never failed to impress me with their knowledge. A special thank you to Kieran Aland who does such a fine job at Queensland Museum’s inquiry centre too…you’re a champion Kieran!

Ok back to my mole crab Albunea symmysta.

I would like to tell you a whole lot more about this species but there really isn’t that much out there in google land about this fascinating animal. It appears to be infrequently seen as it lives under the sand and is rarely encountered like so many animals that occupy our beach ecosystems.

12 June 2010 should have been a red letter day with my new crab find, unfortunately the return trip was marred by idiots driving on the beach.
Here is a pic of this same fool reversing back (note the reverse lights) as he didn’t get up onto the dunes the first time.
And some of the damage...
Our own species needs to learn that beaches aren’t barren wastelands of sand but are dynamic ecosystems just like rainforests and mangroves.

Beaches contain a fascinating array of interesting and important species and should be treasured and respected for all that they are.

Cheers Russ