Philippines: New Damselfly Found in Threatened Rainforest Could
Fight Disease
10/18/99
*******************************
RELAYED TEXT STARTS HERE:
Title: New Damselfly Found in Threatened Rainforest Could Fight
Disease
Source: Environment News Network, http://www.ens.lycos.com/
Status: Copyright 1999, contact source for permission to reprint
Date: October 18, 1999
Byline: Michael Bengwayan
MANILA, Philippines, October 18, 1999 (ENS) - The
vanishing damselflies and dragonflies in the Philippines,
considered by ecologists to be nature's best predator of
disease bearing mosquitos, are stronger by one with the
discovery of a new damselfly species.
The insect, never before seen by scientists and totally
unknown to the world of science, was discovered clinging
to life in a rainforest threatened by logging in Cebu, an
island province of the Philippines.
The new damselfly, temporarily tagged Cebu recionemis, was
discovered in the Tabunan forest by Teobaldo Borromeo, a
Filipino entomologist and lepidopterist who works as a
research aide with the Germany based Senckenberg Museum.
He is also known for having identified as many as fifty
butterflies in Cebu.
Damselflies and dragonflies, in the order Odonata, are
considered the most important predator of mosquitoes
including some of the most dangerous ones such as Aedes
aegypti which spreads dengue fever and the Anopheles
mosquito which is responsible for malaria.
In the Philippines damselflies have become increasingly
rare due to widespread agricultural insecticide misuse and
abuse and unabating destruction of ponds and swamps which
are the insects' natural habitat.
The discovery, now confirmed by entomologists like Dr.
Franz Scheidenshwarz of the University of San Carlos in
Cebu, has yet to be recorded in the "List of Odonata of
the World," a universal documentation of damselflies and
dragonflies being compiled by entomologists Martin Schorr
and Martin Linbeboom of Germany and American Dennis
Paulson.
The World Dragonfly Association (WDA) and the
International Dragonfly Fund (IDA), agencies created to
protect and conduct research on damselflies and
dragonflies, have yet to receive an official communique of
the recent discovery.
No photographs are available of the newly [dragonfly]
discovered damselfly. This photo is of the
world's smallest dragonfly, Nannophya pygmaea from
Malaysia, total length 15 mm. (Photo courtesy University
of Puget Sound)
Worldwide, there are 29 known families and 5,000 species
of dragonflies and damselflies. In the U.S. alone, there
are 11 families and 407 species.
In the Philippines before l980, some 23 families and 689
species were known to exist. The discovery of the
damselfly in the Tabunan forest of Cebu would now increase
the number of species nationally to 690 and worldwide to
5001.
Professor Bony Ligat, a University of Queensland,
Australian-educated entomologist says the insects'
existence is of great economic importance. Regarded as
beneficial insects, they feed largely on mosquitos, gnats
and flies, consuming them in great numbers. With eyes
having as many as 28,000 facets, they can spot mosquitos
25 feet away and travelling at the speed of 60 mph, can
home on their prey. Swarms of them can rid a pond of
mosquitos effectively, Professor Ligat says.
Since 1960s, in its effort to get rid of malaria carrying
Anopheles mosquitoes, Philippine health officials
bombarded ponds, lakes and swamps with DDT, unaware that
in doing so, not only did they kill Anopheles mosquitos
but many beneficial insects like dragonflies and
damselflies as well.
Today, health authorities are doing the same thing,
fogging water holes with deadly chemicals to rid the Aedes
aegypti that spreads dengue, Ligat laments. Dragonflies
and damselflies are the first line of defense against
mosquito build-up, Professor Ligat says. They are even
more effective than frogs and spiders, because of their
mobility. Even their naiads (hatchlings) feed on mosquito
larvae in the water.
The World Health Organization (WHO) in its most recent
Dengue Information Report says it is trying to identify
fish species that can eat dengue mosquito larvae. But Dr.
Charles Cheng, an award winning medical researcher and
director of the Filipino Chinese General Hospital in
Baguio City says, dragonflies and damselflies are better
alternatives to fishes. He is recommending a program which
can reintroduce the damselflies in existing freshwaters in
communities where dengue exists.
Based on reports from the Philippine Department of Health,
Dr. Cheng estimates that dengue fever has killed 1,656
people and infected 32,887 in the Philippines from 1995 to
1998.
Globally, WHO says there are 50 to 100 million cases of
dengue fever, two thirds in South Asia and the Southeast
Asia region. The global prevalence of dengue fever has
grown dramatically in recent decades, and epidemics are
larger and more frequent, Dr. Cheng said.
Dr. Tony Bautista, a regional director of the Department
of Health who heads the anti-dengue program, said he
welcomes research that would look at the breeding of
dragonflies and damselflies and the re-introduction of
them into freshwater areas.
But reintroduction would not be easy, Professor Ligat
says, since these insects breed in freshwater ponds and
swamps, which are rare nowadays in the Philippines,
because of pollution and deforestation.
Damselflies belong to the suborder Zygoptera and
dragonflies to suborder Anisoptera of the order Odonata.
Damselflies are smaller and slender compared to
dragonflies. They are sometimes called "snake doctors,"
"devil's darling needles" and "mosquito hawks."