SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddf5773770e7b17f2bd928e426844a2f0caec52bdbfe93b87dbb8444780c7a60' 
  AND token = 'Z/pdybyxxVoxq8dMCUzG2nfEj6/VKsfnAD+bd5JfWbM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

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