More than 100 emigrant ships are said to have arrived in DS9: "Sanctuary". Many are visible on screen, but only this one can be clearly identified. It is the second ship that passes through the wormhole in the episode. We later see a couple more of this design docked at Deep Space 9. It is a re-use of the Norkova, which was turned upside down. Perhaps this was done on purpose to suggest that it is a different ship (yes, I know that there is no up and down in space, but Star Trek ships always stick to the established flight plane). Since it seems very unlikely that a fleet of them was sent though the wormhole to the Skrreean homeworld, I assume that this design is indigenous to the Gamma Quadrant.
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Various ships, arriving at Deep Space 9 in DS9: "Sanctuary"
Aside from the above "upside down" Norkova, there are several other ship designs used by the Skreeans (which is plausible in a randomly gathered fleet of hundreds of ships). None of them can be identified, and they better shouldn't, because they are all re-uses of Alpha Quadrant vessels anyway. One design of which at least two can be seen would later appear as an apparently Klingon vessel in DS9: "Sons of Mogh". Maybe it is Klingon in "Sanctuary" too?
The Hunter ship appears in DS9: "Captive Pursuit". It is an unchanged re-use of the Zalkonian vessel from TNG: "Transfigurations". Of course, it is virtually impossible that the two ships are actually related to each other.
The Tosk ship appeared in DS9: "Captive Pursuit". It is a redress of a copy of the Vulcan ships from TNG: "Unification". The original model from the TNG episode still exists today. Aside from the color (which is brown instead of bluish gray), several modifications were made to the model, such as the small curved wings and an additional superstructure at the aft end. From the dialogue and the interior view we get the impression that it is very small, probably only shuttle-sized. The cockpit window as visible from inside matches the white window-like detail visible on the top of the model. Also, in the episode there is one external view of Tosk's ship docked at one of the smaller ports in the docking ring of DS9, where it appears to be about 20m long.
The Wadi ship appears in DS9: "Move Along Home". The miniature was later re-used for various cargo vessels of the Alpha Quadrant, including Bajoran ships on three occasions and the Xepolite freighter in DS9: "The Maquis". The latter episode shows a close view and reveals that the model has an unusually great deal of detail for an alien ship. Considering that the Wadi along with their vessel appeared only once, we may want to give the Xepolite design precedence and imagine the Wadi ship was different. There is one significant difference in any case: For the second appearance as Xepolite freighter the ship was flipped over. The Fact Files erroneously labeled the Xepolite orientation as "Wadi ship". The corrected image on the upper left of this entry may look odd because of the unusual shading but reproduces the look fairly exactly.
"Pup" is Chief O'Brien's nickname for an alien intelligent software that came with the probe. We did not learn the name of the culture from the Gamma Quadrant that sent the probe that carried Pup to Deep Space 9. The probe model itself was a modification of the Cytherian probe originally built for TNG: "The Nth Degree".