Index finger groove..

[tomc]

But how many Flamenco playing gorillas moonlighting as car mechanics do you know? Now where's my Celebrex?

[darkshark]

Hi.
I don't have any callouses. Actually my fingertips are quite soft - the only effects of playing I can see are that the fingerprint is a bit worn. I don't know if this will ruin your own sound or technique, but maybe you could experiment with softening the callouse with moisturising cream. It sounds like many of us play fine without callouses, so perhaps you could dispense with them also.
Darkshark.