It seems the luminous secretion has been recorded for a number of Geophilomorpha, but till now I've only read papers on it for
Strigamia crassipes (which this is not) and
Geophilus electricus. I count 55 pairs of legs, which would probably rule out the latter (as well as the
G. carpophagus suggested by Tiggrx. Based on the antennae it's not
G. flavus either.
Based on the leg count it might be
Geophilus proximus??? And maybe one or two in other genera of which I'm not at all sure they would "feature" luminance
If you still have the animal a good shot of the head and tail areas could help - or better yet, a
very good ventral shots of the tail segments and of some the middle segments (around seg 10-17)...
Cheers, Arp