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Anastrepha and Toxotrypana:
descriptions, illustrations, and interactive keys

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Allen L. Norrbom, Cheslavo A. Korytkowski, Roberto A. Zucchi, Keiko Uramoto, George L. Venable, Jerrett McCormick and Michael J. Dallwitz

Hints on using the keys

Introduction

General

Interactive identification is done by entering characteristics of the specimen into a program. The program then indicates which taxa most closely match this information. Unlike a conventional key, the characteristics may be entered in any order. For more information about interactive keys, and their advantages over conventional keys, see Principles of Interactive Keys (Dallwitz et al. 2000).

The features of interactive-key programs differ greatly, and this influences the speed, accuracy, and convenience of identifications – see A Comparison of Interactive Identification Programs (Dallwitz 2000a). (This refers to an earlier version of Lucid; an update is in preparation.)

In this publication, the interactive keys are presented using the programs Intkey and Lucid. The keys are generated from the same data, but their methods of use and capabilities are somewhat different, as described below.

Feedback

If you find errors in the data, please notify Allen Norrbom. We would also appreciate suggestions for improvements in the presentation of the keys and documentation.

Character numbering

Numbering the characters is sometimes convenient. In Intkey, numbering can be turned on or off by means of the numbering button. Lucid does not have this ability, so character numbers have been added to the character text.

Adequacy of the data

The dataset is still under development, and some taxa are incompletely recorded. As an aid to managing data entry and testing, the status of the recording for each taxon is recorded in the character

Data recording (whether adequate at DiagLevel 1)

1. adequate

2. inadequate (taxon not separated from 1 other taxon)

3. very inadequate (taxon not separated from at least 2 other taxa)

4. a stub (very few characters recorded)

The latter two categories (3 and 4) include species which were not adequately described in the literature, and for which specimens were unavailable for study. Some species, for example, Anastrepha flavissima Hering, A. munda Schiner, and A. mburucuyae Blanchard, were described from males that have not been associated with females, whereas A. cruzi Lima was described from a specimen with no abdomen.

The Intkey ‘DiagLevel’ parameter, which is currently set at 1, determines how many differences between taxa is regarded as ‘adequate’ separation. It is intended to eventually increase this number of differences to 3, to provide more flexibility and error tolerance in the identification process.

During Intkey startup, taxon ‘keywords’, which define subsets of the taxa, are automatically generated from this character, as follows.

recorded – states 1, 2, or 3

adequately recorded – state 1

inadequately recorded – state 2

very inadequately recorded – state 3

largely unrecorded – state 4

The taxa under consideration can be restricted to one of these subsets by means of the Intkey button subset of taxa (Use a subset of the taxa). At program startup, the subset in use is the ‘recorded’ taxa.

Lucid is unable to define these keywords automatically, and although the definitions can be added manually, this has not been done, as we use Intkey for primary testing of the data. In the final versions of the keys, this character and the associated keywords will be removed, as all taxa will be ‘adequately’ recorded. The Lucid key contains only the ‘recorded’ taxa. [?? Paragraph needs modification if 'poorly described' category is to be included in the system - ALN]

Basic identification

Intkey

The top-left pane contains the available characters. When the program starts, the pane is headed ‘Best Characters’. Your identification will usually be quicker and more accurate if you use characters near the top of the list.

Intkey window at startup

   1.  In the top-left pane, click on a character that you feel confident you can use.

   2.  The program displays a list of character states, or a box for entering values such as lengths. If there is an illustration for the character, it will be displayed automatically. Some characters have explanatory notes, which may be viewed by clicking the ‘Notes’ button. Click on the state, or enter the value, that applies to your specimen, and click ‘OK’. If you aren’t sure, don’t guess a single state or value. Instead, click on more than one state, enter a range of values, or click ‘Cancel’ and try another character. To deselect a previously selected state, click on it again.

   3.  The ‘Taxa Remaining’ (top-right) pane shows the taxa that match the information that you have entered. The ‘Taxa Eliminated’ (bottom-right) pane shows the taxa that do not match, with the number of mismatches in parentheses. Repeat from step 1 until ‘Identification complete’ or some other message is displayed in the top-left pane. A ‘Help’ button is also displayed; click this to obtain information on how to proceed; for example, how to confirm the identification. (This information is also given in later sections of the current document.)

If, at any stage, you think you have made a mistake and want to correct it, click on the appropriate character in the ‘Used Characters’ (bottom-left) pane. The program again displays the box for selecting character states or entering values, and you can change the information you previously entered. You can remove the character from the identification by clearing all the information.

To start a new identification, click the button restart (Restart identification).

Lucid

The top-left pane contains the available characters (called ‘features’ in Lucid). The characters are originally in their ‘natural’ order, i.e. the order in which they were entered in the database. Before starting an identification: (1) choose ‘Features > Sort Mode > Sort Best’; and (2) click sort best (Sort Best Features). Your identification will usually be quicker and more accurate if you use characters near the top of the list that is now displayed.

Lucid window at startup

   1.  In the top-left pane, find a character that you feel confident you can use. If there is an adjacent plus icon, click it to display the character states.

If there is an adjacent HTML page icon, you can click it to display illustrations and/or notes to help you to interpret the character. Depending on your browser settings, this information will be displayed in a new window or a new tab. Reactivate the window or tab containing the key by clicking on it, or by closing the ‘help’ window or tab.

   2.  For a multistate character, click on the checkbox adjacent to the state that applies to your specimen. For a numeric character, click on the adjacent rectangle use numeric character, enter the value in the window that is displayed, and click ‘OK’. If you aren’t sure, don’t guess a single state or value. Instead, click on more than one state, enter a range of values, or try another character. To deselect a previously selected state, click on its checkbox again.

   3.  The ‘Entities Remaining’ (top-right) pane shows the taxa (called ‘entities’ in Lucid) that match the information that you have entered. The ‘Entities Discarded’ (bottom-right) pane shows the taxa that do not match. Repeat from step 1 until only one taxon remains, or no taxa remain (which means that you have made errors in entering information about the specimen, there are errors in the data, or the taxon to which your specimen belongs is not in the data set).

If, at any stage, you think you have made a mistake and want to correct it, proceed as follows. For a multistate character, select different states by clicking on the appropriate checkboxes in either of the ‘Features’ panes. For a numeric character, click on the adjacent rectangle use numeric character, and enter a new value or range. You can remove the character from the identification by clearing all the checkboxes or values.

To start a new identification, click restart (Restart Key) and sort best (Sort Best Features).

Other techniques

In preparation.