As stated, the Pegasus has only been mentioned in articles relating to Zoic, and there is current no indication that a battlestar of that name does, or did exist within the re-imagined storyline. However, the following is from Ronald D. Moore's blog:
We have discussed the Pegasus storyline for a couple of years now. It's still tooling around inside my brain, but I haven't settled on a take yet. Call it a strong possibility at this point. No plans to see any other battlestars at present.
Pegasus was the second battlestar known to have survived the Cylon Attack. It was commanded by Commander Cain, whom Viper pilots Bojay and Sheba served under. It was the only surviving ship from the Battle of Molecay, meeting up with the Galactica in The Living Legend.
The military genius Cain lead the ship against two Cylon Basestars to permit the Galactica and the Fleet to escape. The question of the survival of Cain and his battlestar was always in doubt, though it is generally assumed by the fandom that the ship survived.
Pegasus is derived from the Greek mythos. Pegasus was a winged horse-god who was the foal of Posideon; this image of a winged horse is emblematic on the Viper Helmet of Pegasus's pilots in The Living Legend.
- Pegasus (from Wikipedia)
--Joe Beaudoin 23:46, 21 Jan 2005 (EST)