While browsing through the Lunar Networks blog I found an article about an unusual secondary crater chain near Rima T Mayer (between Copernicus and Kepler craters). The crater chain is about 3km in length and was probably created as a result of a nearby impact.
Crater chains can be formed in three ways; as primary impacts by a connected string of impacting objects (Comet Shoemaker-Levy is an example), as secondary impacts from a nearby primary impact, and by collapses of volcanic vents along a graben, Rima Hyginus is a good example.
Closeup of secondary crater chain. Latitude: 13.36 N Longitude: 31.19 W
Crater chain in relation to Rima T Mayer
The original article in the Lunar Networks blog is well worth a read and has further images of the crater chain:Crater chain near Rima T Mayer