Strongylocentrotus pallidus Sars 1871 (Str. sachalinicus as junior synonym)
Family: Strongylcentrotidae	Order: Echinoida
Locality: Japan, The Sea of Japan, off Nigata, 500 m	Dimensions: 59 Ø x 28 mm
I got this specimen as Echinus lucidus, but this taxon was apparently wrong, because Echinus has only three pore-pairs. After cleaning with bleach the former more or less violet colour disappeared and the test became green.