SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa2de44436dd9b2892af23d06f8f704c4f523906bfde248de932dad0f6ea2a8e' 
  AND token = 'XHdRn+NiO0WQvEhlOZgxnHnrB5IXDA81afuGeKsjKYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}