QUESTION: Can Lady Bugs be golden?
ANSWER: I had NEVER seen a golden Lady Bug-type beetle until
this spring, 2008. I find that it is a Golden Tortoise Beetle:
Metriona bicolor, family Chrysomelidae
The golden tortoise beetle is a stunning, vibrant metallic gold
color. It has a magical quality, not only because of the brilliance
of its color, but also because the brilliance isn't permanent.
Metriona can alter color within a short time period, turning from
brilliant gold to a dull, spotty reddish color. The gold color
also fades when the insect dies. The gold color is caused by a
thin layer of moisture between the cuticle and an inner layer
of the elytra. Apparently the insect is able to "voluntarily"
squeeze this layer, reducing its thickness and eliminating the
gold color. This change also occurs involuntarily when the beetle
is under moisture stress, and when it dies.
A bit smaller than the more familiar ladybird beetles, the golden
tortoise beetle is configured somewhat like a safari hat with
a narrow "shelf" skirting the outside of the wing covers
and thorax. This "shelf" causes the resemblance to a
tortoise, hence the name. Tortoise beetles are plant eaters. The
golden tortoise beetle in particular feeds on morning glory. They
reside under the leaf, eating a series of small holes resulting
in a characteristic damage pattern.
The larval stage of Metriona is at least as interesting as the
adult, though perhaps not as magical. The larvae also feed on
the underside of morning glory leaves. When they shed their skin,
it remains attached to a prong-like process at the end of the
abdomen. Molts are stacked on molts, and are carried around held
over the insect's back like a parasol. "Parasol beetles"
is indeed another common name for tortoise beetles. When disturbed,
the larvae wave the parasol about, no doubt to intimidate or distract
Tortoise beetles overwinter as adults. In the spring the adults
begin to feed, mate, and lay eggs. More close-up images can be