SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e548a632e87c7b68f79963725902ca01171653e8c11b50bbe26ca4ecce93bb6e' 
  AND token = 'xzBRqy+O+yipmdwpTBSKn5nLkL58Kmv0vnEFdx+9aQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

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