SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd99e814c20869744ff27a70336e5333856e37b4e6a40d55f7236a7ca42ef96c' 
  AND token = 'e7UmJSwss7TrOxybacm+bNaxcC5Zw7wnHjxhs/S2mTQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00247

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