I've started working on fictional designs for the Gepard class, and came across a few unbuilt or short-lived variants which are not documented in SB so far.
The history of that class is fairly complicated, and made all the more confusing by the meltdown of the Russian industry in the 90s and the subsequent scramble for exportable versions.
This means that only the beginning of that history will be covered here.
Disclaimer: The drawings presented here are drawn from scratch from re-scaled drawings, rather than based on Gollevainen's current version. Full credit goes to Golly nevertheless as that drawing has been a major inspiration and source for details, in addition to the usual pilfering of parts from other more current drawings
Though the Tatarstan is the first ship of the Gepard class to enter service, the origin of the project lies in the Pr.11660, which is equipped with much more modern systems. One hull was laid down between 1988 and 1990, but was never completed and had apparently been broken up by 1993. Further work on this variant was discontinued in 1992 due to excessive costs in the post-Soviet economic climate.
According to some sources, the name "Yastreb" was associated to that hull at some point.
In parallel to the Pr.11660 above, meant for domestic Soviet service, an export version was developed under Project 11661 around hopes of India buying up to 12 hulls to replace their Petya-class light frigates. This never came to be, although at least one hull had already been laid down (sources are unclear on the amount of hulls laid down to Pr.11661, but only one survived). The lead boat was launched in 1993 with the full export weaponry typical of a Soviet coastal defense frigate, with the expensive new systems of Pr.11660 replaced by legacy systems: AK-630s and one Osa-MA SAM replaced the Kortik combined CIWS, and the planned Medvedka ASW missile launchers were replaced by 533mm twin torpedo tubes.
The boat was renamed "Tatarstan" in 1996, but was not accepted in service until 2003. At some point in the interval, the ASW equipment was removed and replaced with light weapons.
The drawing below shows the Tatarstan in that interim configuration, although an accurate date is not available.
As usual, comments are welcome.
Redundancy with Gollevainen's current version will have to be addressed at some point, and there's me hoping as well that no one else was working on it in parallel...
Edit: Noticed that the Medvedka launcher box on the Yastreb was my fictional version, and replaced it with a more historical version from the Pr.1145 MPK. Therefore, credit to Eswube for the RPK-9 and Uran launchers.
Edit N°2: Turns out I forgot to fill out the lattice in the back strut below the main mast. Corrected on all variants, along with a few other details like the paint on the shafts.
Edit N°3: As part as a general relocation of my public pictures from Photobucket to Dropbox due to compression problems, I am re-linking these as well, and taking the opportunity to reinstate the separate successive versions. Above the originals are back, below are the same ships, updated following the discussion below:
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The same pic have naturally ressuerected in the internet lately, but It was somewhat joyfull discovery for me to actually find a hard-copy of the same magazine and that very number from a bookfair In Helsinki last autumn. 
