01 August 2011

Giant Mutant Imperial Moths

Here's the title-bearer:

He's about 5", 8 cm from wing tip to wing tip.   The reasons I call him a mutant are a little more obvious in this top view:
He's got 5 legs.  You can see the front left leg, and the doubled front right legs.  The photo couldn't capture it, but I did verify two more back legs.  He also seems to not have antennae, and moths do normally have some, including members of this family.

For completeness, here's the bottom view:
For more technical information, see http://www.butterfliesandmoths.org/species/Eacles-imperialis

It was my first time seeing one of these.  I had seen two other moths of this size -- a Luna moth many years ago, and a Polyphemus a few years ago while I was running in a 24 hour relay.  Turns out they're all in the same family, the Saturniidae.

He was extremely patient with my photography and my wife going in and out of the sliding doors.  Stayed put for several hours. 

Like other members of this family, the adults don't eat.  Go back to the top view -- no mouth parts.  The adults try to reproduce, the females lay their eggs, and a few days later they die.  Their main period of life is as a caterpillar.  I've been calling this a male because it seems (the top link and further checking around the net) that the females are a more straightforwardly yellow.  It is the males who have fair amounts of purple/brown.


jyyh said...

DYK, moths coming to lights are more commonly males, possibly they've hatched too early or too late to find a mate. Also, males of the Saturnids move a whole lot more than the females and maybe found on rare occasions almost anywhere, whereas the females stay put on the better biotopes.

Robert Grumbine said...

Poor guys, working so hard to find a date. A couple of the sources I found did mention that the males were the ones who flew around more.

Anonymous said...

Losing a leg does not make one a mutant Robert. As with many insects the anterior and middle legs are proximate with the posterior legs slightly removed.

Also, you'll find the antennae running along the head from behind the eye towards, and slightly ventral to, the front edge of the wing. The moth is too furry to see them but you can see the groove in the fur in the top down shot.

Chris S.

Robert Grumbine said...

Thanks Chris. I really did look for the antennae there, and couldn't find them.

In saying that the front and middle legs are proximate, do you mean that they come from the same socket (which is what I saw) rather than merely being close?