P. rutulus HUGE female

[The Arthurs]

Hi. Thanks for responses on P. rutulus. Now I have one more thing about that species to say. 

Today, in the front yard in Oakland, CA, I caught a HUGE female rutulus. It has so much orange on the underside that about 1/3 of the hindwing yellow area is obscured by orangish overscaling. On the upperside, it is golden yellow with a striking resemblance to male P. glaucus, having very thick, uneven black bars on the forewing and broad, angular wings. I believe it is a size record for the species, being about 5 1/4" in wingspan. I want the specimen for the collection, but she is full of eggs and needs to oviposit or there may be a shortage of rutulus locally in the next brood. I have her in my backyard butterfly pavilion, with some nectar plants and a small Raywood ash for ovipositing. 

I believe that the variation in P. rutulus is caused by different host plants. I know at least two host trees in my neighborhood (a willow and a Raywood ash), and suspect some others (such as a sort of cherry tree in the park that the swallowtails flutter around and around). I have found many other host trees in the East Bay Area, including some that are hosts for both P. rutulus and multicaudatus, or only multicaudatus. This raises the question, why are there no P. multicautatus in the coastal Bay Area. This is something I'm trying to find out. I think that it is because the Bay Area is a drier climate than P. multicaudatus pusillus can live in. 

Thanks. 

- Noah Arthur 
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