Mediterranean commercial sponges: over 5000 years of natural history and cultural heritage (Review)

This paper deals with the history of the exploitation of a natural resource made
up of various types of Mediterranean horny sponges. It also provides an update
on trends in the trade of these sponges. The distribution and taxonomic status
of Mediterranean species of commercial interest belonging to the genera Spongia
and Hippospongia are reported upon and partly emended by (i) the selection of
neotypes for Spongia mollissima, Hippospongia communis, and Spongia agaricina
from the Indo-Pacific Ocean versus the Mediterranean Spongia lamella, and (ii)
the discussion regarding the problematic status of Spongia zimocca. Attention is
also focused upon species that have been of recent commercial interest as
sources of metabolites with biomedical potential, such as Dysidea avara, which
is considered endangered due to a pressing demand for the industrial extraction
of chemicals it produces (e.g. Avarol). The wild harvesting of new target sponges
is also discussed, together with a proposal for a rational, sustainable, long-term
strategy for Mediterranean sponge management. Sponge culture in situ is suggested
as a useful approach that may allow eco-compatible management and
conservation of this natural resource.