Red-bordered Emerald (7033)

Nemoria lixaria

Family Geometridae, subfamily Geometrinae (emeralds)
Photograph copyright by Tony Leukering

27 May 2012

Belleplain S. F. Headquarters

CMMP block F09
Distribution map

This post's primary point is to illustrate the great contributions that amateurs can make to the knowledge of moth distribution. While I first took this to be yet another version of Red-fringed Emerald (more on this in a post about that species that will get done at some point), closer scrutiny revealed a few anomalies. The pattern of the red border, the single black discal spot on each wing, and the color and distribution of the abdominal spots pointed to Red-bordered Emerald. There was only one problem, the new guide by Beadle and Leckie did not map the species as occurring north of central Virginia. However, as the authors of that guide will agree, the maps presented are just gross generalizations of distribution, based on ecoregions (see pp. 16-18) and the existing specimen record. Moths are not birds and have not had the intense following by hobbyists that birds have enjoyed. Thus, the ranges of the vast majority of species are exceedingly poorly known. [17 June 2012 addition: The range map of the species on the Moth Photographer's Group page does show the species as occurring in New Jersey.] Though I knew all this, I would have retained a bit of doubt, but the ID was confirmed on Bug Guide (which I heartily recommend for questions of bug ID). Finally, though moths are known to vagrate (yeah, I know, spellchecker doesn't think that this is a word, but I'm using it anyway), the fact that I found a different, much-more-worn individual at the same site the next day suggests to me that the species is resident here.