My friend measured a coastal rosy at 49 inches. The snake was brought to his house by a kid who claims he found it on the way up the San Bernardino mtns near Crestline, CA. That is awefully high elevation I would think for a wild rosy, so I am suspicious of the origin.

Whatever the real origin of the snake, it did top 4ft. Gigantic rosy for sure. That must have been 15 years ago.

I found a monster female in Murrieta, CA that was definitely over 36 inches, but I couldn't give an actual measurement. Probably around 40 inches as a guess. Huge animal. Big head too.