Page 31 - Adventures through the World of Entomology

A JOURNEY THROUGH THE WORLD OF ENTOMOLOGY A JOURNEY THROUGH THE WORLD OF ENTOMOLOGY
WITH NORM EHMANN BS, MPH, BCE, RS WITH NORM EHMANN BS, MPH, BCE, RS

ADVENTURE THREE ADVENTURE THREE
“A TRIP TO THE HEAD” “A TRIP TO THE HEAD”

Our first two Adventures gave us a definition of an insect and a look at the various orders of the class Our first two Adventures gave us a definition of an insect and a look at the various orders of the class
Insecta. In Adventure Three, we will zero in on the head of an insect and take a close look at several of Insecta. In Adventure Three, we will zero in on the head of an insect and take a close look at several of
the structures of the head that are vital to its survival– and the knowledge of which may help us greatly the structures of the head that are vital to its survival– and the knowledge of which may help us greatly
in the control of insects. in the control of insects.

First of all, a familiarity with the antennae of insects can help us in identifying the insect or in telling First of all, a familiarity with the antennae of insects can help us in identifying the insect or in telling
it apart from another insect, or even in some instances knowing whether the insect on hand is male or it apart from another insect, or even in some instances knowing whether the insect on hand is male or
female. female.

FOR EXAMPLE — The antennae of termites are FOR EXAMPLE — The antennae of termites are
referred to as moniliform, or bead like. They look ANT ANTENNA TERMITE referred to as moniliform, or bead like. They look ANT ANTENNA TERMITE
like a bunch of beads strung on a string and they ANTENNA like a bunch of beads strung on a string and they ANTENNA
stick out straight in front of the termite. Looking at Scape stick out straight in front of the termite. Looking at Scape
them under a microscope they appear encircled with Funicle them under a microscope they appear encircled with Funicle
hairs or bristles. On the other hand, the antennae of hairs or bristles. On the other hand, the antennae of
ants which are commonly confused with termites by ants which are commonly confused with termites by
the layman have a base (called a pedicle), a very long Elbow the layman have a base (called a pedicle), a very long Elbow
segment (called a scape) and then a varying number segment (called a scape) and then a varying number
of smaller segments (called funicles). In some ants of smaller segments (called funicles). In some ants
the smaller segments at the end of the antennae can Photos by Stennett Heaton the smaller segments at the end of the antennae can Photos by Stennett Heaton
Courtesy of UNVAR
Courtesy of UNVAR
be enlarged to form a “club.” The antenna is jointed be enlarged to form a “club.” The antenna is jointed
and at the juncture of the scape and the funicle is elbowed — just like our arms are elbowed. With this and at the juncture of the scape and the funicle is elbowed — just like our arms are elbowed. With this
information a service technician can determine immediately if he is dealing with an ant or a termite information a service technician can determine immediately if he is dealing with an ant or a termite
— no matter what the homeowner says. — no matter what the homeowner says.

FOR EXAMPLE — There are two species of very small, light-colored ants that look very much FOR EXAMPLE — There are two species of very small, light-colored ants that look very much
alike and it is important to be able to identify them accurately. They are the “Grease” or “Thief” ant, alike and it is important to be able to identify them accurately. They are the “Grease” or “Thief” ant,
Solenopsis molesta, and the “Pharaoh ant,” Monomorium pharaonis. A look at their antennae with a 10 Solenopsis molesta, and the “Pharaoh ant,” Monomorium pharaonis. A look at their antennae with a 10
power hand lens will reveal that both have an antennal “club.” In the case of the Pharaoh ant the “club” power hand lens will reveal that both have an antennal “club.” In the case of the Pharaoh ant the “club”
is formed by the last three antennal segments; in the case of the Thief or Grease ant, the antennal club is is formed by the last three antennal segments; in the case of the Thief or Grease ant, the antennal club is
formed by the last two antennal segments. formed by the last two antennal segments.

Funicle Funicle
Club Pharaoh ant Club Pharaoh ant
3 segmented club antenna
3 segmented club antenna
with 3 segments Scape with 3 segments Scape

Thief ant Thief ant
2 segmented club antenna 2 segmented club antenna
Photo Courtesy of UNVAR Photo Courtesy of UNVAR

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