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'Alamihi crab

Metopograpsus messor

Description:

The species exhibits sexual dimorphism. Males, as pictured, tend to have more purple and/or red coloration.

Habitat:

Rocky tide pool in the Pacific ocean.

Notes:

This appears to be underwater mating behavior. During this behavior, the purple crab repeatedly flexed its claws and picked at the other's shell. Note the algae growing on either individual.

1 Species ID Suggestions

fishpicshi
fishpicshi 8 years ago
'Alamihi crab
Metopograpsus messor Alamihi Crab, Metopograpsus messor


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9 Comments

mauna Kunzah
mauna Kunzah 7 years ago

You're welcome, Chief! Glad to share.

Thank you Mona and this is interesting!

mauna Kunzah
mauna Kunzah 8 years ago

Wow, thank you for all of the info, fishpicshi.

fishpicshi
fishpicshi 8 years ago

Mating behavior, males tend to have more purple on the claws. Purple color is especially bright on a similar species, M. thukuhar: http://www.marinelifephotography.com/mar...

Burnuhwill
Burnuhwill 8 years ago

Yes, that's interesting. They could be different species. Whether they are or not, it's still an interesting spotting. I'd like to see if you find out anything new about them.

mauna Kunzah
mauna Kunzah 8 years ago

I'm wondering if these crabs are both the same species.

mauna Kunzah
mauna Kunzah 8 years ago

Interesting, right? Thanks for your insight, Burnuhwill.

Burnuhwill
Burnuhwill 8 years ago

It's difficult to see, but I believe the one with the exposed underside looks like a female. The position their in doesn't seem like typical crab coitus though, so I'm not really positive of what is going on here.

mauna Kunzah
mauna Kunzah 8 years ago

Does anyone know which one the male is?

mauna Kunzah
Spotted by
mauna Kunzah

Hawaii, USA

Spotted on Jan 3, 2013
Submitted on Mar 4, 2013

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