Apodemia virgulti arenaria

Sand Dunes Metalmark

Subspecies arenaria is distinguished from nominate virgulti in several ways: the dark areas on the wings are more blackish-gray on both sides, whereas virgulti is more brownish (this was more noticable to the naked eye, and some more than others); the two white spots in the basal area of the dorsal forewing are usually smaller, and the postbasal white spot near the inner margin is usually absent or nearly so as in these photos; on the hind wing, the postmedian white spots are well-developed; and finally, the host is Eriogonum parvifolium while nominate virgulti uses fasciculatum. However, these are less important distinctions than what one sees in DNA work: arenaria may look similar to other mormo species, but it appears to have branched off the family tree before any others, a result that is a real surprise, but it's been repeated.

Apodemia virgulti arenaria
This is Apodemia virgulti arenaria, an Eriogonum parvifolium feeder from the sand dunes west of LAX. The same area (and the same plants) hosts the far more famous El Segundo blue. This butterfly was once considered typical virgulti, but DNA studies have shown that it is (very) different. Don't be surprised if/when it is given full species status, as it stands apart genetically from all the other members of the mormo-complex. May 21, 2008.
Apodemia virgulti arenaria
Different individual. It took a long time (over a year and several attempts) to get these photos, since most of the habitat for arenaria is fenced-off.
Apodemia virgulti arenaria
Ventral view of A. virgulti arenaria. Playa del Rey, August 28, 2009.
Apodemia virgulti or dialeuca arenaria
A fresh sand dunes metalmark on its host buckwheat. Playa del Rey, August 28, 2009.

©Dennis Walker