SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1e49f635ce8ac2aa58a974b3ff55d5e05970650f478e05bdecad3d4a541a13b' 
  AND token = 'pGaImuNQoYWu8QL3FvzmKvA+nkqeSBtSaBLdG2nQiyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables