A New North Pacific Heterochone Transferred from Aphrocallistes (Porifera: Hexactinellida)

A hexactinellid sponge specimen from southern California, determined as a member of the genus Heterochone, was found to be conspecific with Aphrocallistes beatrix incognitus, a form previously described from the Okhotsk Sea by Koltun (1967). The taxon is redescribed and reassigned as a new combination, Heterochone incognitus (Koltun). It represents an addition to the North American Pacific fauna. The simple zoological diagnosis of Heterochone is: Aphrocallistidae with atrialia as pinular hexactins