USING SCALARANE SESTERTERPENES TO EXAMINE A SPONGE TAXONOMIC ANOMALY

A parallel study was conducted on two Indo-Pacific foliose sponges, Th e first specimen contains 3-hydroxy-20,22-dimethyl-20-deoxoscalarin (2 ), while the second contains 3-oxo-20,22-dimethyl-20-dioxoscalarin 8 ( 3). The physical properties as well as X-ray results confirming the st ructure and stereochemical features of these compounds are presented f irst. The difficulty we encountered in the taxonomic identification of these species is also discussed, One of our specimens rs identical to material considered by different taxonomists as either Phyllospongia vermicularis or Dysidea vermicularis, The other is identified as Carte riospongia sp. We outline that the parallel chemistry of these two spe cimens suggests that they are closely related taxonomically.