SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e16a4d961d4cfc1f51f307fe8feadb806cba7a175213226b0a7881e8a1ecbdbf' 
  AND token = 'XoLhcZ76oSdRfDs27DlNG8rPLNcpNXyk8l2DaP9LQwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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