Thanks. certainly a new species for me, and I guess very few people walk along the track there. Closer inspection difficult - very steep slope either side of railway cutting, and it wasn't on my side!
Although not within the CNM or NSW Bionet records this location does have 2012 and 2018 records in the Atlas of Living Australia -nevertheless a good find and great to have it now within ACT records (even if it is on the NSW side of the railway line, in fact all of the rail reserve at this location is in NSW
That railway line has many more of this plant further south, past Royalla, many hundreds of them, as seen back in 2017: Swainsona recta (Small Purple Pea)
The populations of S. recta along the railway line between Michelago and Tralee are managed by the Threatened Species Unit of Environment NSW, Queanbeyan Office. Last October I participated (as an NPWS volunteer) in a large scale count of the numbers of individual S recta plants along this stretch of the line, run by Dr John Briggs from the Department. I am sure this Tralee population was included in the count, but I did not go as far as Tralee having finished at Tuggeranong, although I later heard about this large population. Maybe the reords have not yet gone onto Bionet.