Vanessa and the white dot

[Grkovich, Alex]

I have  pretty good series of cardui from various locations in North
America, and a couple of specimens from Europe. I don't think any of these
specimens have this white dot (I'll check tonite but I think this is the
case.). Virtually all (or all) of my virginiensishave it. To me, the white
dot is diagnostic for virginiensis and not for cardui. I think Ron
gatrelle's assessment that the specimnen in the photo is aberrant is
reasonable.

> -----Original Message-----
> From:	Michael Gochfeld [SMTP:gochfeld at EOHSI.RUTGERS.EDU]
> Sent:	Monday, November 19, 2001 8:47 PM
> To:	
> Cc:	
> Subject:	Re: Vanessa and the white dot
> 
> Will Cook's photos are really very interesting and sobering.  Glassberg
> also
> emphasizes the "bold black median FW band" on V. cardui
> as well as the absence of the white spot.
> 
> I find that more often than not, I see the ventral surface of nectaring
> "ladies" in which case the two large ocelli on the ventral hindwing of
> V. virginiensis stands out compared with the four smaller spots of V.
> cardui.   I have often seen V. virginiensis where the white spot was not
> visible due to wear, but I've never seen a cardui with the white spot, so
> this is an interesting aberration, pointing out the importance of getting
> a
> good enough look to see a combination of characters.   H.F. Nijhout used
> V.
> cardui as one of his experimental subjects reported in his book "The
> Development and Evolution of Butterfly Wing Patterns".
> Interestingly he showed that cold shock produced alterations in the 4 spot
> pattern and that individuals without the four ventral eyespots could be
> produced experimentally.
> 
> It would be interesting to know how often the white spot appears in
> cardui,
> particularly in those areas where thousands are reported (we don't seen
> thousands in a whole year here (NJ).
> 
> Mike Gochfeld
> 
> Will Cook wrote:
> 
> > Several field guides (e.g., Glassberg) and other sources (e.g.,
> > http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm)
> > mention that one way to tell American Lady (Vanessa virginiensis) from
> > Painted Lady (Vanessa cardui) is the presence of a small white spot in
> > the orange field below the black apical patch in American Lady.
> >
> > However, on 11/11/01 I found a Painted Lady with a white dot - this is
> > apparently not reliable field mark.  I just posted a photo of this
> > Painted Lady at http://www.duke.edu/~cwcook/pix/paintedlady.html (second
> > photo).
> >
> > --
> > Charles W. "Will" Cook                  w 919-660-7423
> > http://www.duke.edu/~cwcook            cwcook at duke.edu
> > Box 90340, Biology Dept., Duke Univ., Durham, NC 27708
> >
> >
> >  ------------------------------------------------------------
> >
> >    For subscription and related information about LEPS-L visit:
> >
> >    http://www.peabody.yale.edu/other/lepsl
> >
> 
> 
>  
>  ------------------------------------------------------------ 
> 
>    For subscription and related information about LEPS-L visit:
> 
>    http://www.peabody.yale.edu/other/lepsl 
>  

 
 ------------------------------------------------------------ 

   For subscription and related information about LEPS-L visit:

   http://www.peabody.yale.edu/other/lepsl