World Congress of Malacology Antwerp ... - Unitas Malacologica

share morphological features of the shell, being able to observe a pattern common of external
iridescence and predominant spiral cords on a more delicate axial sculpture. Furthermore, we perform
a comparison of the shell morphology of the new Falsimargarita species with the others species of
this genus presently known in the Antarctic waters.
Biodiversity and conservation of freshwater molluscs in the Plateau Lakes of Yunnan Province,
SW China
Aldridge, David C.
Aquatic Ecology Group, Department of Zoology, University of Cambridge, CB2 3EJ, UK,
Email: d.aldridge@zoo.cam.ac.uk
The Plateau Lakes of Yunnan fall within an international biodiversity hotspot. The molluscan fauna
of this region is very poorly known, with numerous synonyms within the sparse Chinese literature.
Comparison of recent shell beaches with living material shows that increased pollution of the lakes
over the past 30 years, in addition to the introduction of non-native taxa, have resulted in dramatic
declines in molluscan biodiversity. The high molluscan endemism in the region suggests that many
species have become extinct. To date we have discovered at least ten new species of gastropods and
bivalves, including unionids and Corbicula spp. A key driver of these extinctions is likely to be the
loss of aquatic macrophytes. However, we have shown that the invasive water hyacinth provides an
important refuge habitat for the remaining invertebrates, and therefore small patches should be
retained until indigenous plants can re-establish. We are also using the indigenous Chinese giant
mussel, Anodonta woodiana, as a tool for the biomanipulation of the lakes. Pilot tests have proved
encouraging, and we are currently propagating the mussel for scaled-up restocking programmes. In
the longer term we plan to propagate some of the threatened unionid mussels.
The use of microencapsulated BioBullets in the control of invasive bivalves
Aldridge, David C.
Aquatic Ecology Group, Department of Zoology, University of Cambridge, Downing Street,
Cambridge CB2 3EJ, UK,
Email: d.aldridge@zoo.cam.ac.uk
The widespread invasion of bivalve molluscs such as the zebra mussel, Dreissena polymorpha,
golden mussel, Limnoperna fortunei, and false mussels, Mytilopsis spp., has made them some of the
world’s most economically and ecologically important pests. Despite the development of numerous
control methods, chlorination remains the only widespread and licensed technique throughout the
world. Mussels are able to sense chlorine and other toxins in their surrounding environment and
respond by closing their valves, thus enabling them to avoid toxic effects for up to three weeks.
Furthermore, prolonged dosing of chlorine in raw water produces ecotoxic trihalomethanes (THMs)
by reaction with organic material in the water. We have developed a novel, environmentally safe and
effective method for controlling the biofouling mussels; the BioBullet. Our method uses the
encapsulation of an active ingredient (such as KCl) in microscopic particles of edible material. The
mussels’ natural filtering ability then removes and concentrates the particles from the water, without
stimulating the valve-closing response. By using the mussels’ filtering behaviour to concentrate
BioBullets the absolute quantity of active ingredient added to the water can be reduced substantially.
Our approach allows us to engineer the particles to break-up and dissolve completely within a few
hours, thus eliminating the risk of polluting the wider ecosystem. We have demonstrated that the
effectiveness of a toxin in the control of biofouling filter-feeders can be enhanced greatly by using
our technique. Furthermore, successful industrial trials indicate that the BioBullet provides a viable
and more appealing control option than those currently in use.
5