Thanks to Ken-ichi Ueda for putting up the black-light that attracted this Proserpinus lucidus and one other male, seen below:

 

These two males (and virtually nothing else, except for two tiny true bugs) were found at the light about 4 hours after dark on a fairly cold winter night (right nearby there was thick ice on my windshield pre-dawn the night before). The habitat was (mostly non-native) grassland (former cattle-ranch land) within open oak woodland at 1880' elevation. Skeleta of last year's Clarkia were abundant nearby...Clarkia is a host plant genus for P. lucidus.

I've added a number of "Print References" to the Info page for Proserpinus (=Arctonotus) lucidus which provide biological info and can be read online.

It's not surprising that only males were seen, according to Rubinoff(2001):

"Female specimens are rare in collections: there are only 7 of 285 (2.5%) field collected specimens in the Essig Museum (U.C. Berkeley), the Bohart Museum (U.C. Davis), the Los Angeles County Museum, and the San Diego County Museum combined."
Males can be distinguished by their wider, more serrate antennae...and also by the relatively wide and truncate posterior end of their abdomen. In females, the end of the abdomen abruptly tapers to a narrowly cylindrical tip...see Josiah's image below:

 

Adults of this species have vestigial non-functional mouthparts and do not feed...all feeding takes place during the larval stage. Indeed, few nectar flowers are available in the early season when they typically fly.

A curious tidbit here...in my photo at the top of this page, the 4 black spines visible below the base of the moth's right antenna are the apical spurs of its right fore-tibia (see full-size image here). The tarsi at the terminal end of its right fore-leg appear to be folded back 180° under its thorax...to see this examine closely the 2nd image of this series. It's not clear to me whether his left antenna is missing or tucked under his body here.