SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd73f9899c8b0c80297cc1af9f9c228ceb46b1a95b2c01de1b00ca106d0ac795d' 
  AND token = '3U/UlD1O/pNMfGpt34ELj6aUpeJ6WV58Cgp894X3AHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

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