I've looked, but can't come up with any references for this unique ventral marking.

Schizocosa avida (Walckenaer, 1837)


http://www.bioone.org/doi/abs/10.1636/04-80.1?prevSearch=&cookieSet=1

that certainly does look very close. The dorsal heart mark is a little wider than the ones we current have in the guide, but I won't argue if you move it there.

does avida have the same ventral pattern?

in the reference above, if you scroll down it shows the ventral pattern of avida. The image in the reference is of a spider that is either a little emaciated or dead, but the pattern is certainly the same.

I have the Dondale keys and S. retrorsa is described as having a black venter w/ a white mark in the middle, not avida.

mf retrorsa (Banks, 1911)....................USA, Mexico [urn:lsid:amnh.org:spidersp:019217]
Pardosa r. Banks, 1911: 453, pl. 34, f. 3, 6 (Dmf).
S. r. Gertsch & Wallace, 1937: 20, f. 12 (m).
Scaptocosa r. Roewer, 1955c: 293.
S. r. Dondale, 1969: 755, f. 1-2, 9-11, 23 (Tmf from Scaptocosa=Geolycosa).
S. aulonia Dondale, 1969: 754, f. 12-13 (f, misidentified).
S. r. Dondale & Redner, 1978a: 163, f. 21, 75-78 (Tmf).
S. r. Dondale & Redner, 1990: 77, f. 76, 78, 80-82 (mf).
S. r. Stratton, 2005: 374, f. 12, 20 (mf).

Which year of Donale Keys do you have? What was the description for Avida?

wow! a down-loadable version: pdf file, 20 MBs, takes a few minutes to load, but here ya go :) 1990 is the year
avida venter: yellow to pale reddish brown, often with narrow
black bands

http://www.esc-sec.ca/aafcmonographs/insects_and_arachnids_part_17.pdf

it sounds like we should wait and sort that out before moving this anywhere.

great, thanks!