Saturday, April 9, 2016

Abbot's Sphinx Moth

Abbot's Sphinx Moth on the screen, its abdominal tip in its characteristic upright position - REK
I was closing the window one early morning at Bull Creek when I saw a dry leaf stuck to the inside screen that hadn't been there the night before.  It turned out to be a very cold Abbott's Sphinx Moth, Sphecodina abbottii.  How it managed to pupate and emerge as an adult in the house is beyond me.  Their usual time is May to June in most of its range and the males are reported to fly around dusk, the females flying near midnight.
Note glimpse of the yellow patch on the covered hind wing - Jon Rapp
Peterson's guide describes it as having deeply scalloped outer wing margins with swirling black lines.  It has a bright yellow patch on the basal hind wing that doesn't show in pictures with the wings folded at rest.  The abdomen ends in an unusual 3-pronged tip that it holds upright.  I tried to photograph it later in the day but the overcast sky dulled its colors so I turned to Jon Rapp as usual.
 First instar - Jo Ann Poe-McGavin 
 Last instar -  Jo Ann Poe-McGavin

The larvae feed on grape species, Vitis and Ampelopsisare.  They are equally cool looking, going through dramatic changes with each molting.  As described in Bugguide:
Knob as an "eye" - REK
"Larvae start out green with a horn on the final segment. Middle instar larvae are whitish to blue-green with dark faint cross-stripes and the horn replaced by an orange raised knob on the last segment (A8). The last instars may be either brown with a "wood-grain" pattern or brown with ten pale green saddles along the back. In these late instars the knob resembles an eye."
Note the 3-pronged furry abdominal tip held upright - REK
I kept my specimen in the refrigerator to get a better sunlit picture of the antennae.  It is described as flying with a buzzing noise, resembling a bee with its flashes of yellow.  Holding it, I could feel the buzzing as it warmed up its flight muscles, its oval body impossible to grip until it made its buzzing escape into the wild.  A much better fate than clinging to our screen, looking longingly at freedom.
Released, just before flying off - REK
Not to be out done, Kevin Firth sent me his gorgeous picture of a new (to us) moth he photographed at Rocky Barrens CA recently.  This is likely Kent's Geometer, Selenia ketaria.

1 comment:

  1. From a distance, the subject appears to be not much more than over-wintering plant detritus of leaves, spider silk and what not stuck to a screen; a grand ruse.