Reading up on the orange fruited genes and carotenoids.
The tangerine allele t has been known for a long time. According to
Genetic Improvement of Solanaceous Crops: Tomato, Volume 2 edited by M K Razdan, A. K. Mattoo....."
Pigment compositions of nearly all orange-fleshed cultivars available for commercial and home use attribute their color to the tangerine allele."
Elsewhere the variety Tangerine is identified as the type example.
Jubilee is another common example of the t gene (Tangerine X Rutgers).
Interesting data on the carotenoid content of r, t, tr here with a good picture of the colour phenotypes:
http://www.pnas.org/content/early/20...08109.full.pdf
Virescent orange is a TGRC mutant allele of t. Accessions with that mutation are listed at the bottom:
http://tgrc.ucdavis.edu/Data/Acc/GenDetail.aspx?Gene=vo
Beta is dominant to og and crimson. Like Delta, the source is from introgressions from wild Lycopersicon species, afaict, rather than a simple mutation in tomatoes that would be found scattered among the heirlooms. L. cheesmanni accumulates beta-carotene instead of lycopene in fruit due to the Beta allele, and so do some other green fruited Lycopersicon spp. So orange varieties with cheesmanni heritage would probably get it from Beta.
This TGRC page lists accession numbers for both Beta and Delta here and there are photos of the fruit phenotypes. Lots of history and info on each accession if you click on the links.
http://tgrc.ucdavis.edu/Data/Acc/GenDetail.aspx?Gene=B