NEWS105
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Republic/Haiti, Puerto Rico, and other
partsof theworld.Bycontrast theseapple
snails donot represent aproblem in their
original homeland, namely South
America. And the apple snails originally
native toAfrica andAsia, that ismembers
of thegenera
Afropomus
,
Lanistes
,
Pila
,and
Saulea,
have so far not turned out to be
harmful to rice. In fact the Asian
Pila
species at least have been partially
suppressedby the invaders andarebeing
studied inorder toascertain theeffectson
their populations. Not only rice but also
numerousothermarshandaquaticplants
areconsumedbyPomacea species,and in
some cases brought to the verge of
extinction in places where these apple
snailsoccur.
The sourceof the Ebro snails
It is unknown how
Pomacea insularum
came to be in the Ebro Delta. It doesn’t
seem very likely that they are released
aquarium specimens, as it is primarily
another species that is kept in the
aquarium hobby (more of that anon),
though thepossibilitycannotbe ruledout
completely. So, once again an urgent
appeal to all aquarists: please, never
release any livestock that you don’t want
or can’t keep any longer! In the vast
majority of cases such animals will die a
painful death,but the few that survivecan
White cultivated formof theapple snail
Pomaceadiffusa
Blue cultivated formof theapple snail
Pomaceadiffusa
they originate from the temperate zones
of South America, and because the
various apple snail species are virtually
impossible todistinguishexternally,aban
onall specieswas imposed tobe safe.
Aworldwideplague
Apple snails of the genus
Pomacea
are
nowadays regarded as dangerous,
invasive species worldwide. The reason
that we now have at least a rudimentary
knowledge of their biology and in
particular their systematics is that some
species (
P. caniculata
,
P. insularum
,
P.
diffusa
, and
P. scalaris
) have spread across
largepartsof South-EastAsiaand someof
themhavealsoproved tobe seriouspests
in rice plantations. As a result money has
been freed up for the otherwise much
deridedbasic research required to reveala
few fundamental facts.Aswell as inSouth-
East Asia (Burma, China, Guam, Hong
Kong, Indonesia, Japan, Cambodia, Laos,
Papua New Guinea, the Philippines,
Singapore, South Korea, Taiwan, Thailand,
Vietnam), apple snails of the genus
Pomacea
are also spreading across parts
of the USA, and in the Dominican
