Second fraction into timesamp [Apache errorlog timestamp]

value=>"Tue Mar 08 10:51:38.971058 2016" is malformed at ".971058 2016"", :config_parsers=>"EEE MMM dd HH:mm:ss yyyy"

I am trying to pass Aapache error log into logstash with timestamp being log time rather than parsing time.

something like:
date {
match => [ "timestamp", "EEE MMM dd HH:mm:ss yyyy", "EEE MMM dd HH:mm:ss.SSS yyyy", "EEE MMM dd HH:mm:ss.SS yyyy" ]
target => "@timestamp"

Can anyone guide me what is the value that can be used for those fractions after second in example above "38.971058"?

Since you have microseconds use SSSSSS instead of SSS. Note that ES won't store microsecond resolution.