I collected this female from a yellow flower on March 22. She made an egg sac in captivity on March 30. The egg sac hatched on April 17. There were approximately 90 hatchlings. The hatchlings were too small to feed live fruit flies, and I have had success in the past raising Mecaphesa dubia hatchlings on half-crushed fruit flies, but these did not appear to take to them, and I only succeeded in raising one to adulthood. I got photos of a confirmed adult male and a confirmed immature female.
I took three spiders identical to this one from that location. None would eat crickets. I could only get them to eat live flies, so long as the flies were no larger than their bodies. Apparently they are finicky even as hatchlings.
The offspring that survived to adulthood turned out to be a clear male Mecaphesa celer. (I'm lucky it was male!) The other offspring I photographed molted just as many times as the male but still wasn't an adult and didn't have penultimate male palps, so it's clearly an immature female. Here are the two offspring:
I also posted photos of the epigynum, both ventrally and dorsally. The dorsal view is a pretty good match for celer, matching figure 471 in Dondale & Redner 1978. The dorsal views for the remaining two yellow Mecaphesa weren't as clearly M. celer, but I didn't get any offspring from them for additional ID help.
Note, though, that there also appears to be a red-patterned phase of M. celer: