Tharsalea arota nubila

'Cloudy' Tailed Copper

Tharsalea arota nubila is a scarce tailed copper described nearly a century ago from Griffith Park in Los Angeles County. According to Ken Davenport's update on the Emmels' book, nubila was extirpated from there long ago. However, there is a single sighting there from 2010 on the iNaturalist website, so it's possibly hanging on there, perhaps in an obscure corner of the park. I found a couple of male tailed coppers at another known site, Santa Anita Canyon near Mt. Wilson, on June 26th, 2019. I searched for females the next day because it is the dorsal coloration of the females that really sets these apart from nomiate arota, which I've found to the east in Big Dalton Canyon and more recently to the south in Riverside and San Diego Counties, as well as at Big Bear. John A. Comstock - who named the subspecies - described nubila as darker and with a wider marginal band than nom. arota. My return trip yielded only a couple more males. I would return a third time - on June 27th - and then again in July on the 1st, the 3rd, the 8th, the 11th, 22nd, 26th, and - finally - the 31st, before seeing a single female. So it is clear that males emerge well before females and increase in numbers over a period of weeks, staking out territories such as open pathways from a perch, such as a shrub or low tree branch. They are easy to find along a hiking trail. The females I've seen were on or even in the host bushes, ovipositing on stems, basking, or just resting. So what worked for me was to be patient and carefully check the host plants. As a side note, while there is an ex-larva nubila from 1983 in the McGuire collection illustrated on the BoA website, the few females I got a look at appear more like nominate arota. So what is going on with these? To find out, I intend to photograph females in the Santa Monica Mountains for comparison, and this page will change. It may be that the old range of this subspecies - east to Mt Wilson - has changed, with true nubila no longer found in the San Gabriels. We'll see.

Nubila was named by John A. Comstock in 1926, and the types were collected in early July, 1922, from Griffith Park, at the far eastern end of the Santa Monica Mountains. As noted above, they ranged east to Mt. Wilson, which is in the San Gabriel Mountains. Santa Anita Canyon arota are approximately 2.5 air miles SE of Mt. Wilson. The host is Ribes aureum var. gracillimum, golden currant.