A key is a tool used to identify or diagnose specific objects or situations. Keys use a process of elimination where the user is presented with a series of choices that describe features of the object. By selecting those choices relevant to the specimen to be identified, those objects that do not match the selected choices are rejected. This allows the rapid elimination of large numbers of objects that the specimen cannot be. The process continues until only one object or a short list of objects remains, identifying the specimen or at least providing a short list of possible identities.
Keys that follow a tree structure. This is the type of key built using Lucid Phoenix.
Dichotomous keys are the most common keys encountered. They may be laid out in various ways, but usually form a series of numbered questions arranged in “couplets” as shown below:
Each time a question is answered, the user is directed to the number of a new question-couplet. This continues until, instead of a number, the name of the species (or other taxon) is given. This type of key is called a “dichotomous” key because the meaning of the word is "two branching", although in practice dichotomous keys often have questions with more than two choices. The structure of the key is such that each question is actually like a tree branch that has smaller branches proceeding from it, as demonstrated below for keying out four "egg-laying animals".
Multi-access keys, such as those built using Lucid, have in their database character information about the taxa that are to be identified. When the user of a multi-access or matrix key chooses a character state of a selected character in the key, the taxa that have that character state are retained; taxa that have a different character state for the selected character are discarded. When another character is chosen, the same process is repeated with the remaining taxa. Since computers easily handle repetitive tasks at high speed, they are ideal for multi-access keys, which depend on a complete check of all the taxa in the key's database each time a question is answered.
Since multi-access keys allow you to start with any character you choose and to proceed in any order you choose, these keys do not suffer from the unanswerable couplet problem encountered in dichotomous keys. Further, in using a multi-access key you can avoid characters that are difficult for you to distinguish or are not appropriate for your specimen, another advantage of multi-access keys over dichotomous keys.
Ultimately, when using a multi-access key, all taxa except the one that matches your specimen may be eliminated. However, if you cannot eliminate all the taxa, you will be left with a small group of taxa that can then be compared more closely.
The Lucid team can assist you in a variety of activities to support the process of key development and publication.
If you need technical assistance or help with multimedia or packaging tasks involved in developing and distributing your key, our team would be pleased to discuss this with you.
If you would like assistance to develop a key to distribute commercially, please contact us and we discuss how we might assist you to prepare, package and deploy your key to commercial standard. To facilitate the distribution and sale process we can also provide a distribution service by placing your identification product in our online shopping facility.
We also offer a key hosting service at Lucidcentral.org to make your key available on the Internet. For more information on key hosting please contact us.
When you package your key with a player for distribution you should be aware that there are a number of licensing issues that need to be considered. Before packaging any player with your keys you must acquire a licence for each player that you ship on a commercial basis. You also need to ensure that the Player licence agreement that we have supplied to you is brought to the key users attention when they are using the key.
These requirements are intended to ensure that there is no unintended breach of conditions by 3rd party users.
The following table indicates the Player that can be deployed with your key for the method of distribution chosen.
Lucid Player (Application)
Lucid Player (Applet)
For further information please contact us.