Lucid Player v4

What does the Lucid Player do?

The Lucid Player is an effective and powerful identification and diagnostic tool. It is used to play interactive identification or diagnostic keys or guides created using the Lucid Builder.

Lucid keys are usually created by an expert for a particular group of organisms or things (such as fruit flies, frogs, wild flowers, corals, grasses, crop diseases, mouth ulcers or minerals). The key comprises a list of all the Entities (E.g. Species or other taxa, objects, diseases etc.) in the group, a list of the Features that may be used to identify them, and a matrix of scores of the Entities for the features.

When a key is deployed in the Lucid Player, it can be used to identify specimens that belong to the group covered. Specimens are described by selecting, from the list of all Features provided in the key, those Features that match the specimen. At each step, the Lucid Player sorts the list of Entities in the key into those that match the developing description and those that do not. As Features are progressively chosen, the list of matching entities will be progressively reduced until a single Entity (or perhaps a short list of entities) remains. The identification is complete.

Identifying the specimen – finding a name for it – is only the first step in finding out more about it. Links from the key’s entities provide access to fact sheets and other information provided by the key builder. A name is also the starting point for finding information on an organism beyond the key, using the Internet and other resources.

The Lucid Player provides other tools and information to help with the identification. For example, features in Lucid keys are usually provided with explanatory notes and images to help learn about them. Subsets of Features can help organise the list of features to make it easier to manage, and the Player’s Best function is a powerful tool to help decide which feature to address next.

View the topic Using the Lucid Player next, for an introduction to the look and feel of the Player.

Build your own key

If you think you may like to build your own Lucid key, see the topic What does the Lucid Builder do? Or visit, for more information.