SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe442ec235239cd477d2029c0aae2ff0495a136d746c400420bfaf21563ff687' 
  AND token = 'EspD0TNojg9CVvR9FdzaJGm2Twi8WOEAfD2GZHFr+Qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

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