This tutorial contains basic instructions to help new users of Lucid
get started. It is not meant to be a comprehensive help file. You can access the
Lucid Help file any time after opening the key, by clicking on the "Help" icon on the
toolbar (last icon on the right).
Lucid3 is software for creating and using interactive identification keys. Lucid is developed by
Identic in Brisbane, Australia. Visit the
for more information on Lucid and Lucid3.
Any modern web browser can be used, such as Internet Explorer, Firefox,
An interactive matrix key is quite different from a traditional dichotomous key.
Please consult the Best Practices on
occasion to pick up new tips and tricks for using the interactive key.
Web pages such as fact sheets attached to entities in Lucid keys may be considered
pop-ups by certain browsers (such as Internet Explorer). If your
browser blocks pop-ups, you will need to allow pop-ups for this Lucid tool in your
browser's Internet settings.
A Lucid key has four panels.
The upper left window, Features Available, lists the identification features and feature states to choose from.
The upper right window, Entities Remaining, lists the available taxa.
The lower left window, Features Chosen, lists which feature states are currently selected.
The lower right window, Entities Discarded, lists the taxa that have been discarded based on the features that have been selected.
"Features" are characters used to identify the entities. Each feature has at least two states (character states) which
correspond to different forms a feature can exhibit. You can toggle images on and off using the buttons at the top.
Clicking on an icon to the left of a feature or state will display
the image illustrating it.
Do not feel compelled to select features in any particular order. Interactive keys are specifically designed to let the
user start anywhere. If you have a damaged specimen, there will still be features available on undamaged parts of the
Navigating the key
Feature and entity trees can be expanded by clicking the "+" next to the grouping feature or entity. Feature states are
selected by clicking once on the state name or image thumbnail.
Clicking the state a second time deselects the state. As feature states are selected, the entities that do not have those
features will be moved into the Entities Discarded panel.
All entities and most feature states are illustrated with photographs, drawings, or both. As shown above, clicking on the image thumbnail (or image
icon if thumbnails are not displayed) brings up a larger size image and gives the user access to the full image gallery for
the feature state or entity, if available. All entities are also linked to fact sheets for the taxon. Clicking the small grey
page icon next to the entity thumbnail will open the fact sheet in a new browser window. The images provided
do not necessarily reflect all known morphological variation for a particular feature or entity. Every diagnosis should be confirmed by
carefully reviewing the information provided on the fact sheet associated with the species.
In order to
maximize their value and validity, some specialized terms appear in the key and fact sheets. A glossary is linked to the
fact sheets to assist the user in understanding such terms.
If unsure of the correct state of a given feature, it is often better to try a different feature before selecting a state you
are unsure about. However, the key has been coded to accommodate common mistakes and features with states that may vary. For
more hints on navigating the key, see the best practices page.
A potential problem with keys that do not contain all species in a genus is the possibility of a "false positive."
For this reason, it is very important to compare the specimen at hand with the descriptions and images provided in the fact sheets.
If any question remains regarding the identification of the specimen, a specialist should be consulted.