Anyone who is an avid insect collector will immedi-
ately identify with Zahl's excitement at receiving this
unusual package.
Titanus giganteus was first described by Linneaus
in 1771, and to this day no one knows where he
obtained a specimen. In the middle of the 19 th
century specimens were occasionally found
drowned and washed up on the shores of the Rio
Negro near Manaus and, even more remarkably,
discovered intact in the stomachs of large fish being
prepared for the table. The intrepid British ento-
mologist Henry Walter Bates, who spent 11 years
documenting the beetle fauna of the Amazon basin
between 1848 and 1859, was well aware of Titanus.
Although he tried very hard he only managed to find
a few imperfect specimens to send back to England
for sale. For many years the only specimens that
made it to Europe resulted from these chance
encounters, and so lucrative was the very limited
trade in Titanus at the time that enterprising
individuals would hoard incomplete and rotting
specimens recovered from rivers to 'construct'
perfect specimens for sale. To purchase a complete
Titanus in 1914 cost the princely sum of 2,000 gold
marks (the equivalent of around $11,500 US today)
and wealthy collectors would hire steam vessels to
meet incoming ships while still at sea to select the
biggest specimens. Up until 1938 only about 30
specimens had been found, and the bulk of these
were males.
Not a great deal had changed by the time of Zahl's
1957 expedition, which yielded a further 16 male
specimens (all of which flew to powerful security
lights around the mine site) together with,
importantly, all the necessary clues as to how to
collect Titanus in numbers. For some reason, Zahl's
1959 article failed to have much of an apparent
impact on beetle collectors, because Titanus was
still considered rare up until the mid-1980s. It was at
this time that the link between powerful lights and
being able to collect Titanus in commercial
quantities began to gain widespread acceptance,
after the French built a rocket-launching facility in
their South American territory of French Guiana.
Several facts became much better known quite
quickly. Firstly, Titanus was far from being rare. Its
rarity was a perception only and powerful light traps
placed in primary rainforest during the beetle's
relatively short flying period of 4-8 weeks could yield
a reliable annual pulse of specimens. Today,
hundreds of male specimens are collected annually
from light traps set up in French Guiana and also
the Peruvian Amazon. Prices have come down
dramatically for average-sized specimens but really
large ones still command in excess of $1,000 US
each. Females have never been collected at light
traps and the handful that are known have all been
found opportunistically wandering on the ground or
drowned in rivers; they still fetch very high prices
when they occasionally come onto the market.
In spite of its legendary status over the centuries,
we still have no reliable data on the beetle's life
cycle and its breeding sites are not known with