Ryan Photographic - Pisinae - Twin spine or spider crabs
Family Pisidae
This is a speciose family with 646 species recognized, in 86 genera. Like the crabs in the families Mithracidae and Majidae (and others) they are sometimes called "spider crabs" (which is as good a reason as any to use family names ...).
Many species in this family "decorate" themselves with
hydroids or other marine organisms which breaks up their outline and makes them difficult to see.
Hyastenus sp. Decorator crab
 decorator crab Kri Eco, Raja Ampat IMG_8229 med res.jpg)
Hyastenus ? "Decorator crab" Kri Eco, Raja Ampat IMG_8229
Naxioides taurus Decorator crab
, Kri Eco, Raja Ampat, West Papua IMG_3856 med res.jpg)
Naxioides taurus, "Decorator" crab, Kri Eco, Raja Ampat, West Papua IMG_3856
Naxoides taurus Decorator crab, Kri, Raja Ampat, West Papua IMG_0471