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Su, 2012). Molecular studies indicate that
two distinct lineages of
C. formosanus
exist
in the USA and Hawaii with identical
lineages in China, supporting the idea of
multiple introductions of this species
(Austin
et al.
, 2006). Similarly, two different
lineages of
C. gestroi
are found in the USA,
populations from Key West, Florida and
Puerto Rico being most closely associated
with Malaysia (Jenkins
et al.
, 2007).
Likewise, Husseneder
et al.
(2012) reported
at least two introductions in Maui and
multiple introductions into the continental
USA. Conservative analysis of their data
suggests fi ve different sources.
C. gestroi
is
now known to be established in South-east
Asia, the Indian subcontinent, North
America, South America, and islands in the
Caribbean and Indian Ocean (Rust and Su,
2012).
Molecular evidence suggests that three
genetically distinct populations and
independent invasions of
R. fl avipes
into
Canada occurred (Scaduto
et al.,
2012). In
colder climates with shorter seasons, shifts
away from reproduction by primary alates
to secondary reproductives and dispersal by
budding may possibly have contributed to
their successful establishment. The possible
loss of recognition cues might have per-
mitted
R. fl avipes
to form area-wide super-
colonies. Scaduto
et al.
(2012) reported
similarities of both Canadian and French
populations of
R. fl avipes.
In France this
species has become the most abundant and
destructive termite. High interspecifi c com-
petitive capacity, a lack of intraspecifi c
aggression and a high capacity for develop-
ing multiple reproductives in the colonies
of
R. fl avipes
are attributes likely to make
them dominant in their introduced range
(Perdereau
et al.
, 2011). It is notable that the
introduced populations of
R. fl avipes
have
less variability in their cuticular hydro-
carbon profi les than do native populations
in the USA (Perdereau
et al
., 2010b). This
may also help explain the lack of aggression
between populations and fusion between
populations as observed in France. In add-
ition, the propensity of
R. fl avipes
colonies
in France to produce more secondary
reproductives and their capacity to merge
with other colonies compared with Ameri-
can colonies would also contribute to their
success (Perdereau
et al.
, 2010a).
An isolated report confi rmed by genetic
analyses indicated a single introduction of
Reticulitermes urbis
into Doméne, France
from the Balkans. There is no intraspecifi c
aggression and they speculate that this
colony budded and spread forming a large
supercolony. The supercolony occupies an
area of about 6.8 hectares (Leniaud
et al.
,
2009).
Another widely distributed tropical
genus
Heterotermes
also has invasive
species but with rarity. Molecular analyses
suggest that the
Heterotermes
sp. in Florida
originated either in Jamaica or Grand
Cayman (Szalanski
et al.
, 2004). The ability
of this species to forage under dry conditions
allows it to occupy an unfi lled niche in
southern Florida (Scheffrahn and Su, 1995).
Heterotermes convexinotatus
is invasive on
many of the islands in the Caribbean (Evans
et al.
, 2013). Although human activities and
shipboard dispersal are the most likely
reasons of introduction, natural means
cannot be completely ruled out (Perdereau
et al
., 2013). Recent collections of
Hetero-
termes tenuis
in Venezuela suggest that this
species is expanding its range in South
America (Perozo and Issa, 2006).
Increase in international trade increases
the number of invasive species (Westphal
et al.
, 2008). Maritime commerce and ships
are one of the major ways in which termites
are spread across vast ocean areas, especially
for species that are capable of forming aerial
colonies not directly associated with soil.
There have been 133 incidences reported in
Australia and Florida from 1986 to 2009 of
on-board ship infestations of termites. Of
these,
C. formosanus
and
C. gestroi
were
found 40 and 19 times, respectively
(Scheffrahn and Crowe, 2011). Analysis of
infestations of
C. formosanus
and
C. gestroi
in southern Florida revealed that they are
signifi cantly closer to infested boat locations
and marine docks than random points in
the urban environment (Hochmair and
Scheffrahn, 2010). Most infestations are
within 1 km of marine boat dockage
(Scheffrahn and Su, 2005). Hochmair and
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