The Nixe was the deluxe version of the Lloyd and the Halloh, which were all part of the Icarette line. Zeiss sometimes used different names in different markets or at different times for the same camera. The Nixe line actually goes back to Wunsche, which merged to become part of Ica, which then merged into Zeiss. The Zeiss Nixe was produced from 1927 until 1934 in two sizes. Both accepted rollfilm, as well as cut film.
The 551/17 made images 8 x 10.5cm on rollfilm and 9 x 12cm on sheet film. The 551/6 made images 8 x 14cm on rollfilm, 9 x 14cm on sheets.
Both cameras had double extension bellows, lenses included 4.5 and 6.3 Tessar, Dominar and Doppel Protar (Double Protar) most likely in dial set Compur shutter.
This Nixe is an Ica example.
The back, with the cover for rollfilm use partway removed.