This short “best practice” guide shows you how to make the most of the advantages and flexibility of WATTLE identification system and of the LucID software under which it runs. Of course, no two identifications will be the same, and you will need to be flexible in your approach. However, taking note of the suggestions below may help, especially if you are new to Lucid or other interactive keys (much of this information is also relevant to conventional dichotomous keys).
This guide was originally published in the WATTLE User Guide and is based to a large extent on information provided by Kevin Thiele.
The information presented here is especially important if you are familiar with using printed identification keys in books, but are new to interactive keys. An interactive key like WATTLE works in some ways like a printed key but in other ways is quite different. LuciID keys are a type of interactive key called a random-access (or multi-access) key. While the question (couplets) of a printed key need to be answered in a fixed order, in LucID you can address any character at any time. One of the big advantages of this is that you need not get “stuck” by being faced with a question that you cannot answer – if this happens, simply find a question that you can. It is important to use this feature, and not to dwell overlong on a character that is difficult to answer.
This raises another important advantage of a random-access key. There is no need to have a complete specimen to be able to identify it using WATTLE. Of course, the more complete your specimen, the more likely you are to be able to identify it quickly and easily. Many Acacia taxa can be identified by using a combination of phyllode/leaf and inflorescence characters (or phyllode/leaf and pod characters), but you will often be able to narrow the number of taxa down to a short list of taxa to check further.
You will usually find it useful to proceed with an identification using the steps below.
Become familiar with the specimen. Briefly reviewing the characteristics of your specimen before you start will make it easier as you proceed through the identification. Also, some plants possess unusual or distinctive features – using these may enable the specimen to be keyed out in very few steps. As you become increasingly familiar with Acacia and WATTLE you will come to know many of the characters, and you will know where to find them in the key.
Choose the appropriate characters. WATTLE has a wide range of characters, ranging from ones dealing with the obvious and simple features to ones dealing with features that are minute and obscure (these are called cryptic characters). Not all characters have equal discriminating power – some are better than others, depending upon where you are in the identification process. Therefore, choosing the appropriate character is important in getting you most quickly to the “right” answer. The problem is, of course, that unless you are familiar with Acacias it is often difficult to know what characters are appropriate to use in particular circumstances. Fortunately there is some assistance available to you in this regard.
WATTLE divides its characters into ten sets – you can assess these by using the Sets button on the tool bar. You may ask LucID to display all the characters in its list of Characters Available ( this is the All set), or restrict your request to any sub-set of characters, such as Inflorescence characters, Phyllode characters, Geographic characters, etc. Choosing an appropriate set will make Characters Available easier to scan, and prevents it being cluttered with characters that you do not require or cannot possibly answer. You can use the Find button on the tool bar to quickly locate a particular character.
The two FAST FIND sets are of special importance and it is strongly recommended that you commence your identification by using one or other of these: FAST FIND (Phyllodinous taxa) if your specimen has phyllodes or lacks foliage completely, FAST FIND (Bipinnate-leaved taxa) if your specimen has bipinnate foliage. The characters in these sets are designed to most quickly reduce the numbers of remaining taxa to a few. After answering as many questions as you can in the FAST FIND set continue your identification by either loading another character set or by using the Best or Bingo options.
Numeric characters usually have strong discriminating power but it is important to measure accurately, especially if the size is below 5 mm. Also, numeric characters work best if you include a range of values (i.e. smallest and largest) for the organ being measured. Note: record all measurements in WATTLE in millimeters.
For geographic characters it is advisable not to use them too early in the identification (just in case the plant being identified is a new to the area). Also, if a specimen comes from near the boundary between two or more geographic regions, then select several regions to allow for range extensions or geographic imprecision.
Some cryptic characters are especially powerful (e.g. gland position, sepal division and flower merous) but determining them often requires access to a microscope. In general it is best to leave these sorts of characters to late in the identification – if all else fails. The more important of these cryptic characters are included in the set called STUCK! then try these characters.
Always skip a character that you are unsure about. The easiest way to go astray with an identification is to guess at a character that you are unsure about, either because you don’t understand the character or because the character is not clear on the specimen. One of the great advantages of an interactive key is the ability to skip characters – use this feature.
When selecting states, always choose multiple states if you are uncertain of the correct choice. LucID allows you to choose multiple states from one character. These states will be connected with an or link, and LucID will search for all taxa with state A or state B. If you are unsure which of two or more states your specimen has, then choose them all. That way, you can be sure that your target species will remain in Taxa Remaining. (Note, however, that choosing all the states of a character is equivalent to not choosing the character at all, since no taxa would be removed from Taxa Remaining.)
When you have addressed all the obvious characters, ask LucID to suggest the best remaining character. The Best menu option will cause LucID to assess which of the remaining characters will best reduce the list of Taxa Remaining. Using one or other of these “best” characters would give you the most efficient next step. Note, however, that the Best options may work quite slowly if the list of Taxa Remaining is large. It is sensible to start using Best after you have used FAST FIND and have run out of other easy and obvious characters. When you run Best LucID will either sort the characters, the ones with the strongest discriminating power at the top of the list, or find (and highlight) the next best character to use: you can decide which of these options you require by using the Characters/Best Options command.
If you end up with no taxa remaining, review your chosen character states and delete any that you are dubious about. An empty Taxa Remaining list means that no taxon in the WATTLE database matches the selection of character states that you have made. This may be because you have found a new species, or because we have made an error in coding the data. However, it is most likely that you have made a mistake in one or more characters. If you are dubious about any of your choices try deleting the states that you are unsure about to see what effect it has. One or more taxa may move back into Taxa Remaining. In difficult cases, you may need to “play” with the key, adding or deleting character states progressively to try and find the best matching taxon.
Do not assume that you will end up with a single taxon remaining. Some taxa are very hard to differentiate, except by using difficult or obscure characters. Even after you have addressed all the characters that you can, you may still have a short list of taxa remaining instead of just one. But you are still much closer to an identification than you otherwise would have been.
Once you have a potential target taxon (or small group of taxa), check the associated information to see if it matches. Getting a possible name of a taxon from WATTLE is not the end of an identification. You may have made errors, or you may have a species that is not in the key. In these cases, the key may have provided you with the wrong name. Always check the accessory information for the taxon (or taxa), namely, the descriptions and images.