| The backwash from this sucker's prop almost knocked me down
yesterday when it did a fly by with a dismembered leaf beetle held tenderly in its front
paws, impaled on its proboscis. This is the largest (and most
stately, imho) of the Laphria complex flies, a truly stunning
insect.
There are over 7,000 species of robber flies world
wide; nearly 1,000 in North America. All robber
flies have stout, spiny legs, a dense moustache of
bristles on the face (mystax), and 3 simple eyes
(ocelli) in a characteristic depression between their
two large compound eyes. The mystax helps protect the
head and face when the fly encounters prey bent on
defense. The antennae are short, 3-segmented, sometimes
with a bristle-like structure called an arista. The
short, strong proboscis is used to stab and inject
victims with saliva containing neurotoxic and
proteolytic enzymes which paralyze and digest the
insides; the fly then sucks the liquefied meal much like
we vacuum up an ice cream soda through a straw. Many
species have long, tapering abdomens, sometimes with a
sword-like ovipositor.
Male
Bumble Bee |
Female
Robber Fly |
Male brownbelted bumble bee
vs. Female Laphria grossa: Who's
mimicking whom? |
