Species
and cryptic lineages of the red seaweed Asparagopsis
are well-known for their use in biodiscovery, in aquaculture as biological filters
but also as notorious invaders and pests causing decline in biodiversity worldwide.
The species in this genus, A. armata
and the cryptic species complex A.
taxiformis, which embraces at least four genetic lineages, share nearly identical
tetrasporophytes (i.e., the Falkenbergia stage). One of the A. taxiformis cryptic lineages, the
so-called invasive lineage 2, is equipped with unique ecophysiological features.
When conditions are met, in short amounts of time, lineage 2 takes over on other,
less aggressive, non-native or even local endemics and leaves behind
either “dense purple gametophyte forests” or “dense purple tetrasporophyte mats”.
However,
not all of the A. taxiformis cryptic lineages
are invasive. Very often, not all of the Asparagopsis gametophytes or
tetrasporophytes from within the “purple forest” or the “purple mat” belong to
the same lineage. Obviously the prompt identification
of a pest is crucial in support of its sustainable management especially when
the pest is hidden within morphologically identical conspecifics. In
the case of Asparagopsis, only DNA
sequencing could tell gametophytes and tetrasporophytes of the cryptic lineages
apart. But not anymore! Marianela Zanolla (UMA) in her recently
published paper was able to identify morphologically tetrasporophytes
and gametophytes of Asparagopsis species and cryptic lineages collected from
the Mediterranean Sea and the Hawaiian Islands. Basically these are the places
where multiple Asparagopsis lineages are
found within few hundred yards. But please pay attention! If you are a marine aquaria
lover, you still need to purchase a microscope or a PCR for some DNA analyses.
Read more here…
