SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '574e9f66ebfc00456f29dea6fa2076be29e65dd09a40fb933488947f21bc377f' 
  AND token = 'TmSkiFQvIaQsJ8Y+QKXmnxvE6InXRmzTiwyDmS64nzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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