checkered white ~ 09/03/12 ~ Fort Ord

female checkered white (possibly western white)
female Pontia protodice (possibly Pontia occidentalis)
for more information click here and here

posted 09/18/12 - When I started Nature ID back in the spring of 2009, I simply wanted to learn more about local nature. I wasn't fully aware of the extent of challenges I would face creating a virtual collection. Sure, basing IDs solely on photographs, especially my typically crappy ones, has its limitations when experts often rely on actual collection of specimens, dissections, and scopes to distinguish species. But, I figured whatever I casually found during my hikes would be quite common and clearly represented online by people who know way more than I do. This has proven to not always be the case with some of my photographs being the first online of newly described species to the best represented of rare species to possible correction of collections from places like CalAcademy. For a new ID to me, I usually look at 3 to 20+ different sources from my own small collection of field guides, library books, and most often online, especially from reputable online ID resources I've discovered. While comparing several different sources side by side, outliers often become blatantly obvious. I hate to admit to it, but I've become something of an ID policewoman particularly on sites I know other people trust such as Wikipedia, CalPhotos, and BugGuide. In fact, I sent a correction in to a contributor to BugGuide while I was searching for this white butterfly ID.

In the embedded links in the ID under my photograph, I've linked to trusted sites Butterflies of America, Butterflies and Moths of North America (they've made vast improvements to their site in the past 3 years), and Art Shapiro's Butterfly Site. It looks to me like it's a western white based on the pattern and boldness of the markings. However for now, I'm going with a checkered white ID, because westerns have never been reported for Monterey County. As biologist and fellow blogger biobabbler has repeatedly cautioned me, I should not always rely on what other people have reported. I've sent e-mails to Paul Opler, Jim Brock, and Art Shapiro for their expert guidance. I've already heard back from Paul and Jim and will ask if I can quote them in this blog post. I have a feeling Art will have a more definitive answer for me. I'll update this post when I know more.

Btw, the Pontia I show is nectaring on telegraph weed (Heterotheca grandiflora), one of the few flowers I found blooming profusely at Fort Ord on this date.

ps 09/22/12 - Phew!  I've been in several e-mail correspondences regarding this post.  Mike Hoffman at BugGuide was surprisingly quick in getting the ID corrected, even though he's not an editor with access to move IDs.  The three experts I contacted each have authored books on butterflies (linked in their names below) and basically said the two Pontia spp. are difficult to tell apart.  Paul Opler, like me, thought it looks more like P. occidentalis.  Jim Brock suggested I contact Art who is more familiar with butterflies in this region.

Art Shapiro ended up being a gold mine with more detail and PDFs of his scientific papers than I could fully wrap my head around (still trying to figure out how to post PDFs on my blog).  His area of extraordinary familiarity from the greater Sacramento area to the Sierras spans an impressive 40 years.  With his permission, here's what Art said, "I'm sure it's protodice. It's a very fresh, crisply-marked one, but it's still a female protodice. I've gotten nearly identical ones here and in Riverside County--and on the East Coast! Back in the 70s it was sometimes incredibly common in the Salinas Valley and nearby, and it generally peaks regionally in September. Occidentalis has never been reported reliably in the Coast Range south of the Bay, except for the two Doudoroff early-spring specimens from the Santa Cruz Mts. in the 1940s cited on p.106 of my book. (I wanted to ask him if he remembered anything about them, but he had died just a few weeks before I came upon the specimens at Berkeley!)"  M. Doudoroff actually collected these specimens in 1930, which are now housed at University of California, Berkeley's Essig Museum of Entomology and have not been catalogued yet.  Art goes on to state, "Occidentalis has indeed been expanding its range--eastward across Canada and along the US-Canada border, nowhere near here. It does show up very rarely on the floor of the Sacramento Valley (see attachments) in September-October. We don't really understand this. Monterey would be rather an incredible stretch. Nothing is impossible, of course. A P. beckeri was once caught (really) in Colusa County. I suspect the pupa came in on a camper or other vehicle..."  After some questioning on my part and an admission that I was hoping I had found a new Monterey Co. record for P. occidentalis, Art replied, "These two cause lots of confusion, and it doesn't help that where they are sympatric 1-2% may be hybrids. (Here is another old paper about their genetics. It goes back to the Miocene, before the polymerase chain reaction triggered the sequencing revolution. We probably should look at these two genomically as part of our overall hybridization research program. We're doing sulphurs right now.) The 'winter' phenotypes of both are VERY much darker beneath than the 'summer' ones and yes, it is easy to get confused with only singletons or a few specimens, rather than good series. In the 'recurrent enigma' paper, the occis are at the upper left in each group. No, that first record was not a hoax, but I had been cautioned by colleagues to refer to the possibility if only to discount it.  I have raised literally 1000s of these things in the course of research. I don't claim infallibility--only that I'm pretty good with them. Never take 'expert' stuff on faith. I've often been wrong, usually on Speyeria but hardly ever on Pontia or on skippers. But 'hardly ever' does not equal 'never.'"  Art finishes, "Butterfly people can be annoying in the same way as birders. If you can tell your Empidonax flycatchers you are up in the stratosphere with the anabolic-steroid users. Hang in there! Don't be intimidated by 'expertise.' As we age, it metamorphoses into senility."  Gotta love Art!  If anyone would like PDFs of his papers, feel free to contact me and I can forward them to you.