Valdore-class

So nice of the Romulans to build vessels with large target profiles but hardly any space for ship's systems.

The Valdore-class Romulan Warbird appeared in Star Trek: Nemesis. Little is known about these ships, but they appear to be heavily armed. The two assisting the Enterprise-E in attacking the Scimitar were quickly taken out of the fight before we could get a good gauge of their capabilities. They do appear to be significantly smaller than the D'deridex-class warbird commonly seen in TNG.

This ship class further demonstrates how Romulan ship designers obviously flunked their engineering courses (assuming they took any at all), as the design appears to be trying to maximize surface area.

Non-Canon

In the Star Trek: Titan novel "Taking Wing", the Valdore is referred to as a Mogai-class warbird.