Catalpa Sphinx (7789)

Ceratomia catalpae

Family Sphingidae

Photograph copyright by Tony Leukering

7 July 2012

West Cape May

CMMP block X02

Distribution map

With a wingspan reaching 2.75 in. (95 mm), this subtle beauty is one of the largest sphinxes and one of the county's largest moth species. The very similar Waved Sphinx (7787) can be differentiated by subtle details of forewing pattern (particularly those of the sub-terminal [ST] line), but often/usually has the reniform spot filled by white or silver, rather than gray as in Catalpa.

The alternate focus of this essay is a bit of terminology, what is termed in moths as the "reniform spot." The literal translation of "reniform" is kidney-shaped, so it may come as a surprise to many that, in the mothing world, one often finds the seemingly redundant phrase, "Reniform... kidney shaped" (couplet 3 in Eupsilia key). That is because lepidopterists have co-opted the word to note the location of a spot that is often kidney-shaped, rather than using it for its true meaning (I suppose that some bounder could make the above say, "Reniform... reniform"). The reniform spot is just distal (in the sense of toward the end and, in this case, toward the end of the wing) of the median line and close (proximal) to the leading edge of the wing (see Fig. 4 in Beadle and Leckie). The Catalpa Sphinx has an oval reniform spot outlined in black.

The beast in the picture above was nearly the first moth that Mike Crewe saw in his moth trap on the morning of 7 July, probably because of its relative immensity. Once we got it out of the trap, we let it perch on a door jamb on the interior of the mudroom closet of his house to while away the time that we dealt with all of the lesser creatures. Most of the small moths will, given the opportunity, fly away once day comes, but the large species (perhaps because they're so obvious and so loved by avian predators) usually sit tight, counting on their camouflage. Upon getting a few record pictures of the Catalpa Sphinx, we took it outside in order to get "natural" pictures, putting it on the side of Mike's big side-yard stump. After a brief photo session, we took it to a shaded spot and let it go.

[Mike Crewe photographing the Catalpa Sphinx in his side yard. Photo by Tony Leukering]