Salvador Dali sponge identified

The strikingly beautiful sponge we here at Miguel’s Diving call the “Salvador Dali” sponge is Petrosia lignosa. Samples from two sponges were sent to Nicole J. de Voogd of the Institute for Biodiversity and Ecosystem Dynamics, Zoological Museum, University of Amsterdam. After looking at the maze of spicules under a microscope, she was able to identify it. Nicole says that the genus name Petrosia actually means “stony hard.” When compared with other sponges, all Petrosid sponges are hard and rock-like. So far, this sponge is known only from vertical walls in Indonesia. Friends say that this sponge does not occur in Bunaken (North Sulawesi). Nicole, however, disputes this. We at Miguel's Diving suspect this means that it is not present in the most common Bunaken dive sites. Its presence in most current dive sites in the Togian (Togean) Islands remains uncertain. But it is often seen here in Gorontalo on walls in Tomini Bay. This unforgettable sponge was first described in 1925 from the Togians.

The extensive vertical walls of Gorontalo host many fine examples. The samples Nicole saw were taken from the Traffic Jam dive site. Both sponges live at 20 meters on a wall exposed to the open ocean. The smaller sponge is shaped like a squashed vase, measures about 40 cm tall, and has light colored skin. The other one forms a long tube or funnel and is almost one meter long with dark skin. Advanced divers can see a huge one at about 40 m at the Jinn Caves dive site. Sponge samples were taken in such a way as not to be noticed by passing divers.

Divers in Gorontalo can be sure to see this surrealistically carved sponge. Thanks, Nicole, for your help. And our prayers for the safe delivery of your baby!