The Devil is in the DETAIL.
One of these geckos is ‘true blue’; the other is an insidious invader....
but which is which?
One is a native Australian, whose close relatives featured in a famous field study by Dr Robert Bustard in
the Pilliga Scrub of northern NSW in the 1960s. The other is an opportunistic exotic, often associated with
human habitation, whose arrival in this country can be traced back to 1845. Gehyra dubia is an inoffensive
native species, whereas Hemidactylus frenatus, the Asian House Gecko, has managed to expand its
dominion to include Africa, America, the Mediterranean, and various islands of the Indian and Pacific
Oceans. It will often supplant native species in its quest for territory.
Although the Asian House Gecko is typically more vocal, with a characteristic ‘chit-chat’ call, it is very
similar in appearance to Gehyra spp., so just how do you conclusively tell the troublesome pest from the
fair dinkum Aussie?
The truth can be revealed thanks to some amazing photography from Michael Cermak. Under magnifica-
tion, Hemidactylus frenatus is easily distinguished by two characteristics. The first digit is considerably
reduced in size (this is not visible
from above), and the tail has rows of
blunt, pointed scales running trans-
versely, or crosswise.
1.
3.
2.
1. This mild-mannered Gehyra dubia is
easily confused with...
2. ...the insidious colonist, Hemidactylus
frenatus!
3. Commonly known as the Asian House
Gecko, H. Frenatus can be distinguished
by a considerably reduced first digit.
4. It is also identifiable by the rows of
blunt, pointed scales on its tail.
All images by Michael Cermak.
4.