Some new or little known sponge species living in the scleraxis of colonies
of Corallium elatius from the Japan Sea and Corallium sp. from Midway Isla
nds (Pacific Ocean) have been studied. The assemblage is composed of five s
pecies: two of them are new (Holoxea excavans, Scantiletta macroxeata). Tho
osa am phiasterina is recorded for the first time since its description, th
e very rare T. bulbosa and Dotona pulchella have been collected for the fir
st time in the Pacific Ocean. The boring capacity of the genus Holoxea is a
ssessed for the first time.