You'll access a maximum of seven main areas in the screen. Not all of them are shown at once, but they can appear and dissappear depending on the content shown. When accesing the "home page", you'll discover five of them:

Areas 1, 2 and 3 appear in every page, no matter the content. Zone 1 is the logo. Clicking on it will take you to the home page
Zone 2 carries the "Taxon Search" widget. If you want to know if a taxon is available to use, write here any part of the name. Let's say I'd like to introduce an story about Cataglyphis albicans, but I'm not sure if it's available. Typing "albic" and clicking on "Search" will offer:

Clicking in any name shall show the results page for that taxon. If the one you're searching for is not listed, you'll need to add it to the taxa list before submitting any content related to it.
A quite complex tool which varies depending on the user role. Its functionalities are explained in detail here
Helpful zone to show different blocks containing submenus or information related to the content shown. Its content varies depending on the section, and does not appear in some cases as in distribution maps.
The desired content is shown here. Sometimes it expands to cover the whole width and sometimes it shrinks when the Right and Left bars are populated, as in the next example:

This line appears in some cases to make easier to jump to other parts of the site. For example, when viewing a camponotus species, this is the breadcrumb shown:

Clicking in any term will take you to the summary page of that particular issue
With the same characteristics than the Left bar, it shows some useful tips on the content shown, but not navigational aid. In the image above, a Gmap of the specimen is shown, but other tips can appear.