Nupetiet Vergnitz (Flagship)
The Nupetiet Vergnitz is Breetai's flagship. Breetai is the name of the commander of the Zentraedi forces present in the animated series. He'll be discussed later in a post covering "characters". The Nup-Verg is only seen as Breetai's vessel. It is unknown if the ship is one of many flagship-class vessels or if it is a special vessel for Breetai only (unlikely). It is gigantic, larger than the SDF-1 and bristling with all manner of weapons and a huge complement of mecha. There is limited information on most of the Zentraedi ships seen in the series. The Nupetiet Vergnitz is showing moving a large portion of its front section (opening almost) to fire its main cannon.


Additional ships of this type are visible in some massed fleet shots. It appears to be a standard heavy cruiser or super-heavy cruiser class. The two-tone livery appears to denote the ships command/flagship status: the others are just the basic green like the other ships listed/shown here.
Quiltra-Queleual
Another ship which is frequently seen - but I have zero info on it. Perhaps a standard light carrier or frigate/destroyer? No size comparison that I can find.

IIRC these are troop transports.
Qualitra-Quelamitz
Another vessel I don't even recall seeing in the show. It's been detailed in some fan posts, but I have no information on it. Assume another ship of some sort of naval service.

Heavy beam destroyer (or something similar to that effect). The fore section splits open along the latitudinal line to become a single giant version of the two-pronged energy weapon seen on other ships as CIWS/AA turrets. Intended for cap ship killing and orbital bombardment, I'd guess, but I don't remember exactly.