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<p />
<h2><a name="SDD_Part_0_Introduction_and_Prim"></a> SDD Part 0: Introduction and Primer to the SDD Standard </h2>
<p />
<h3><a name="2_4_Dichotomous_keys"></a><a name="2_4_Dichotomous_keys_"></a> 2.4 Dichotomous keys. </h3>
<h4><a name="2_4_1_Traditional_dichotomous_ke"></a> 2.4.1 Traditional dichotomous keys. </h4>
<p />
Dichotomous keys (Box 2.3.1) are specialised identification tools comprising fragments of descriptive data arranged in couplets forming a branching tree. Each fragment (lead) comprises a small (occasionally verbose) natural-language description. Each node in the tree typically has two branches (dichotomy) but may have three (trichotomy) or more branches. Several differing formats of dichotomous keys are traditionally used.
<p />
<h4><a name="Box_2_4_1_Typical_dichotomous_ke"></a> Box 2.4.1 - Typical dichotomous keys </h4>
<p />
<p />
<div align="center">
		<table bgcolor="#ddddff" border="0" cellpadding="5" style="border-collapse: collapse" bordercolor="#111111" width="80%" id="table7" >
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px; border-top-style: solid; border-top-width: 1px">
				<b>Key to Ascomycete genera</b></td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px; border-top-style: solid; border-top-width: 1px">&nbsp;</td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px; border-top-style: solid; border-top-width: 1px">
				<br>
				Ascus unitunicate</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px; border-top-style: solid; border-top-width: 1px">&nbsp;</td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">&nbsp;&nbsp;&nbsp; 
				Clypeus present around ostiolar neck</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">&nbsp;</td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
				Clypeus poorly developed</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">
				<i>Glomerella</i></td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
				Clypeus well developed</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">
				<i>Hyllachora</i></td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">&nbsp;&nbsp;&nbsp; 
				Clypeus lacking</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">&nbsp;</td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
				Ascus widest in middle</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">
				<i>Physalospora</i></td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
				Ascus clavate or cylindrical</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">
				<i>Glomerella</i></td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">
				Ascus bitunicate</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">&nbsp;</td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px">&nbsp;&nbsp;&nbsp; 
				Ascostroma uniloculate</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px">
				<i>Guignardia</i></td>
			</tr>
			<tr>
				<td width="409" style="border-left-style: solid; border-left-width: 1px; border-bottom-style: solid; border-bottom-width: 1px">&nbsp;&nbsp;&nbsp; 
				Ascostroma muliloculate</td>
				<td align="right" style="border-right-style: solid; border-right-width: 1px; border-bottom-style: solid; border-bottom-width: 1px">
				<i>Botryosphaeria</i></td>
			</tr>
		</table>
	</div>
	<br>
	<div align="center">
		<table bgcolor="#ddddff" border="1" cellpadding="5" style="border-collapse: collapse" bordercolor="#111111" width="80%" id="table8">
			<tr>
				<td style="border-left-style: solid; border-left-width: 1px; border-right-style: none; border-right-width: medium; border-top-style: solid; border-top-width: 1px; border-bottom-style: none; border-bottom-width: medium" colspan="3">
				<b>Key to Australian skinks in the genus <i>Ctenotus</i></b></td>
			</tr>
			<tr>
				<td width="50" style="border-left-style: solid; border-left-width: 1px; border-right-style: none; border-right-width: medium; border-top-style: solid; border-top-width: 1px; border-bottom-style: none; border-bottom-width: medium">1</td>
				<td style="border-left-style: none; border-left-width: medium; border-right-style: none; border-right-width: medium; border-top-style: solid; border-top-width: 1px; border-bottom-style: none; border-bottom-width: medium">Dark upper lateral zone with one or more distinct series of 
				pale spots or blotches along the body</td>
				<td width="114" valign="bottom" align="right" style="border-left-style: none; border-left-width: medium; border-right-style: solid; border-right-width: 1px; border-top-style: solid; border-top-width: 1px; border-bottom-style: none; border-bottom-width: medium">2</td>
			</tr>
			<tr>
				<td width="50" style="border-left-style: solid; border-left-width: 1px; border-right-style: none; border-right-width: medium; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">1a</td>
				<td style="border-style: none; border-width: medium">Dark upper lateral zone obscurely mottled or uniform with at 
				most a few pale spots anteriorly</td>
				<td width="114" valign="bottom" align="right" style="border-left-style: none; border-left-width: medium; border-right-style: solid; border-right-width: 1px; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">3</td>
			</tr>
			<tr>
				<td width="50" style="border-left-style: solid; border-left-width: 1px; border-right-style: none; border-right-width: medium; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">2</td>
				<td style="border-style: none; border-width: medium">Fewer than 25 lamellae under the fourth toe; supralabials 7-8 (usually 7); prefrontals separated</td>
				<td width="114" valign="bottom" align="right" style="border-left-style: none; border-left-width: medium; border-right-style: solid; border-right-width: 1px; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">
				<i>C. arcanus</i></td>
			</tr>
			<tr>
				<td width="50" style="border-left-style: solid; border-left-width: 1px; border-right-style: none; border-right-width: medium; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">2a</td>
				<td style="border-style: none; border-width: medium">More than 25 lamellae under the fourth toe; supralabials 8-9 
				(usually 8); prefrontals usually in contact</td>
				<td width="114" valign="bottom" align="right" style="border-left-style: none; border-left-width: medium; border-right-style: solid; border-right-width: 1px; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">
				<i>C. alleni</i></td>
			</tr>
			<tr>
				<td width="50" style="border-left-style: solid; border-left-width: 1px; border-right-style: none; border-right-width: medium; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">3</td>
				<td style="border-style: none; border-width: medium">Pale mid-lateral stripe passes over the hindlimb to continue 
				along the tail </td>
				<td width="114" valign="bottom" align="right" style="border-left-style: none; border-left-width: medium; border-right-style: solid; border-right-width: 1px; border-top-style: none; border-top-width: medium; border-bottom-style: none; border-bottom-width: medium">
				<i>C. inornatus</i></td>
			</tr>
			<tr>
				<td width="50" style="border-left-style: solid; border-left-width: 1px; border-right-style: none; border-right-width: medium; border-top-style: none; border-top-width: medium; border-bottom-style: solid; border-bottom-width: 1px">3a</td>
				<td style="border-left-style: none; border-left-width: medium; border-right-style: none; border-right-width: medium; border-top-style: none; border-top-width: medium; border-bottom-style: solid; border-bottom-width: 1px">Pale mid-lateral stripe extends to groin, then continues 
				along the front edge of the hindlimb</td>
				<td width="114" valign="bottom" align="right" style="border-left-style: none; border-left-width: medium; border-right-style: solid; border-right-width: 1px; border-top-style: none; border-top-width: medium; border-bottom-style: solid; border-bottom-width: 1px">
				<i>C. coggeri</i></td>
			</tr>
		</table>
<p />
<p />
<div align="center">
<table bgcolor="#ddddff" cellspacing="2" cellpadding="2" style="border-collapse: collapse" bordercolor="#111111" width="80%">
  <tr> 
    <td colspan="4" align="left" style="border-left-style: solid; border-left-width: 1px; border-top-style: solid; border-top-width: 1px; border-right-style: solid; border-right-width: 1px; border-bottom-style: solid; border-bottom-width: 1px"><b>Key to <i>Aira</i> naturalized in Australia</b></td>
  </tr>
  <tr> 
    <td style="border-left-style: solid; border-left-width: 1px" width="5%" height="35" rowspan="3" valign="top">1.</td>
    <td width="50%" height="15" valign="top">Inflorescence open and spreading</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top">2</td>
  </tr>
  <tr> 
    <td width="50%" height="15" valign="top">Inflorescence dense and spike-like</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top"><b>*</b><b>A. 
      praecox</b></td>
  </tr>
  <tr> 
    <td width="50%" height="10" valign="top"></td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="10" valign="top"></td>
  </tr>
  <tr> 
    <td style="border-left-style: solid; border-left-width: 1px" width="5%" height="35" rowspan="3" valign="top">2.</td>
    <td width="50%" height="15" valign="top">Pedicels 3-8 times spikelet length</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top">3</td>
  </tr>
  <tr> 
    <td width="50%" height="15" valign="top">Pedicels up to 3 times spikelet length</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top">4</td>
  </tr>
  <tr> 
    <td width="50%" height="10" valign="top"></td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="10" valign="top"></td>
  </tr>
  <tr> 
    <td style="border-left-style: solid; border-left-width: 1px" width="5%" height="35" rowspan="3" valign="top">3.</td>
    <td width="50%" height="15" valign="top">Spikelets c. 3.5 mm long</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top"><b>*A. provincialis</b></td>
  </tr>
  <tr> 
    <td width="50%" height="15" valign="top">Spikelets c. 2 mm long</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top"><b>*A. elegantissima</b></td>
  </tr>
  <tr> 
    <td width="50%" height="10" valign="top"></td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="10" valign="top"></td>
  </tr>
  <tr> 
    <td style="border-bottom-style: solid; border-bottom-width: 1px; border-left-style: solid; border-left-width: 1px" width="5%" height="35" rowspan="3" valign="top">4.</td>
    <td width="50%" height="15" valign="top">Spikelets 2-2.5 mm long</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top"><b>*A. cupaniana</b></td>
  </tr>
  <tr> 
    <td width="50%" height="15" valign="top">Spikelets 2.5-3.2 mm long</td>
    <td style="border-right-style: solid; border-right-width: 1px" width="45%" height="15" valign="top"><b>*A. caryophyllea</b></td>
  </tr>
  <tr> 
    <td style="border-bottom-style: solid; border-bottom-width: 1px" width="50%" height="10" valign="top"></td>
    <td style="border-right-style: solid; border-right-width: 1px; border-bottom-style: solid; border-bottom-width: 1px" width="45%" height="10" valign="top"></td>
  </tr>
</table>
	</div>
</div>
<p />
<p />
<p />
<h3><a name="2_4_2_SDD_representation_of_dich"></a> 2.4.2 SDD representation of dichotomous keys </h3>
<p />
While dichotomous keys can be presented in various formats, the essential elements of all dichotomous keys are identical. Each consists of a tree of questions, each with two (or occasionally more) possible choices, each choice leading to another question or a taxon.
<p />
A dichotomous key rendered in SDD requires three essential items: the names of the taxa being described, a set of questions (leads) used to separate the taxa, and the nodes defining the structure of the leads.
<p />
A simple SDD instance document for dichotomous key data has the basic structure shown below and in Example 2.4.2.
<p />
There are at least two different ways of generating a dichotomous key in a well structured SDD instance document, using statements or questions, these will be dealt with separately.
<p />
<img alt="identificationkey.gif" src="http://wiki.tdwg.org/twiki/static/_publish/identificationkey.gif" />
<p />
<h4><a name="Example_2_4_2_Dichotomous_keys_w"></a> Example 2.4.2 - Dichotomous keys within SDD </h4>
<p />
<table bgcolor="#ddddff" border="0" width="100%" cellpadding="5" cellspacing="5" style="border-collapse: collapse" bordercolor="#111111">
<p />
<tr>
<td>
<p />
<pre>
   &#60;Datasets&#62;
   
     &#60;TechnicalMetadata&#62;
      ... information about the generator (Technical metadata)
     &#60;/TechnicalMetadata&#62;
    
       &#60;Dataset&#62;
      
         &#60;TaxonNames&#62;
           ... naming the entities described (Taxon names)
         &#60;/TaxonNames&#62;
         
           &#60;IdentificationKeys&#62;
          
             &#60;IdentificationKey&#62;
               ... the dichotomous key structure  (see below)         
             &#60;/IdentificationKey&#62;
            
           &#60;/IdentificationKeys&#62;
       &#60;/Dataset&#62;
   &#60;/Datasets&#62;

</pre>
<p />
</td>
</tr>
<p />
</table>
<p />
<h3><a name="2_4_3_Dichotomous_keys_using_sta"></a> 2.4.3 Dichotomous keys using statements </h3>
<p />
A dichotomous key structured with statements consists mostly of the elements &lt;lead&gt; and &lt;result&gt;. &lt;Lead&gt; points to another couplet while &lt;Result&gt; points to a taxon name.
<p />
<h4><a name="Example_2_4_3_Structure_of_dicho"></a> Example 2.4.3 - Structure of dichotomous keys within SDD (statements) </h4>
<p />
<table bgcolor="#ddddff" border="0" width="100%" cellpadding="5" cellspacing="5" style="border-collapse: collapse" bordercolor="#111111">
<p />
<tr>
<td>
<p />
<pre>
  &#60;IdentificationKey id&#61;&#34;key1&#34;&#62;
    &#60;Representation&#62;
     &#60;Label&#62;Key to Australian Aira Using statements &#60;/Label&#62;
    &#60;/Representation&#62;
    &#60;Leads&#62;
     &#60;Lead id&#61;&#34;lead1&#34;&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Inflorescence open and spreading &#60;/Label&#62;
      &#60;/Statement&#62;
     &#60;/Lead&#62;
     &#60;Result&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Inflorescence dense and spike-like &#60;/Label&#62;
      &#60;/Statement&#62;
      &#60;TaxonName ref&#61;&#34;t1&#34;/&#62;
     &#60;/Result&#62;
     &#60;Lead id&#61;&#34;lead2&#34;&#62;
     &#60;Parent ref&#61;&#34;lead1&#34;/&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Pedicels 3-8 times spikelet length &#60;/Label&#62;
      &#60;/Statement&#62;
     &#60;/Lead&#62;
     &#60;Lead id&#61;&#34;lead3&#34;&#62;
     &#60;Parent ref&#61;&#34;lead1&#34;/&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Pedicels up to 3 times spikelet length &#60;/Label&#62;
      &#60;/Statement&#62;
     &#60;/Lead&#62;
     &#60;Result&#62;
     &#60;Parent ref&#61;&#34;lead2&#34;/&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Spikelets c. 3.5 mm long &#60;/Label&#62;
      &#60;/Statement&#62;
      &#60;TaxonName ref&#61;&#34;t2&#34;/&#62;
     &#60;/Result&#62;
     &#60;Result&#62;
     &#60;Parent ref&#61;&#34;lead2&#34;/&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Spikelets c. 2 mm long &#60;/Label&#62;
      &#60;/Statement&#62;
      &#60;TaxonName ref&#61;&#34;t3&#34;/&#62;
     &#60;/Result&#62;
     &#60;Result&#62;
     &#60;Parent ref&#61;&#34;lead3&#34;/&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Spikelets 2-2.5 mm long &#60;/Label&#62;
      &#60;/Statement&#62;
      &#60;TaxonName ref&#61;&#34;t4&#34;/&#62;
     &#60;/Result&#62;
     &#60;Result&#62;
     &#60;Parent ref&#61;&#34;lead3&#34;.&#62;
      &#60;Statement&#62;
       &#60;Label&#62;Spikelets 2.5-3.2 mm long &#60;/Label&#62;
      &#60;/Statement&#62;
      &#60;TaxonName ref&#61;&#34;t5&#34;/&#62;
     &#60;/Result&#62;
    &#60;/Leads&#62;
   &#60;/IdentificationKey&#62;
</pre>
<p />
</td>
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</table>
<p />
<p />
<h3><a name="2_4_4_Dichotomous_keys_using_que"></a> 2.4.4 Dichotomous keys using questions </h3>
<p />
When a dichotomous key in an SDD instance document is structured with questions the statements act as answers to questions rather than independent statements.
<p />
<h4><a name="Example_2_4_4_1_Structure_of_dic"></a> Example 2.4.4.1 - Structure of dichotomous keys within SDD (questions) </h4>
<p />
<table bgcolor="#ddddff" border="0" width="100%" cellpadding="5" cellspacing="5" style="border-collapse: collapse" bordercolor="#111111">
<p />
<tr>
<td>
<p />
<p />
<pre>
  &#60;IdentificationKey id&#61;&#34;key1&#34;&#62;
   &#60;Representation&#62;
    &#60;Label&#62;Key to Ascomycete genera&#60;/Label&#62;
   &#60;/Representation&#62;
   &#60;Question&#62;
    &#60;Label&#62;Is the ascus unitunicate&#60;/Label&#62;
   &#60;/Question&#62;
   &#60;Leads&#62;
    &#60;Lead id&#61;&#34;lead1&#34;&#62;
     &#60;Statement&#62;
      &#60;Label&#62;yes, unitunicate&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;Question&#62;
      &#60;Label&#62;Is a clypeus present&#60;/Label&#62;
     &#60;/Question&#62;
    &#60;/Lead&#62;
    &#60;Lead id&#61;&#34;lead2&#34;&#62;
     &#60;Statement&#62;
      &#60;Label&#62;no, bitubinate&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;Question&#62;
      &#60;Label&#62;Is ascostroma uniloculate&#60;/Label&#62;
     &#60;/Question&#62;
    &#60;/Lead&#62;
    &#60;Lead id&#61;&#34;lead3&#34;&#62;
    &#60;Parent ref&#61;&#34;lead1&#34;/&#62;
     &#60;Statement&#62;
      &#60;Label&#62;yes, clypeus present around ostiolar neck&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;Question&#62;
     &#60;Label&#62;Is clypeus well developed&#60;/Label&#62;
     &#60;/Question&#62;
    &#60;/Lead&#62;
    &#60;Lead id&#61;&#34;lead4&#34;&#62;
    &#60;Parent ref&#61;&#34;lead1&#34;/&#62;
     &#60;Statement&#62;
      &#60;Label&#62;no, clypeus lacking&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;Question&#62;
      &#60;Label&#62;Is ascus widest in middle&#60;/Label&#62;
     &#60;/Question&#62;
    &#60;/Lead&#62;
    &#60;Result&#62;
    &#60;Parent ref&#61;&#34;lead3&#34;/&#62;
     &#60;Statement&#62;
      &#60;Label&#62;clypeus poorly developed&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;TaxonName ref&#61;&#34;taxon1&#34;/&#62;
    &#60;/Result&#62;
    &#60;Result&#62;
    &#60;Parent ref&#61;&#34;lead3&#34;/&#62;
     &#60;Statement&#62;
      &#60;Label&#62;clypeus well developed&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;TaxonName ref&#61;&#34;taxon2&#34;/&#62;
    &#60;/Result&#62;
    &#60;Result&#62;
    &#60;Parent ref&#61;&#34;lead4&#34;/&#62;
     &#60;Statement&#62;
      &#60;Label&#62;ascus widest in middle&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;TaxonName ref&#61;&#34;taxon3&#34;/&#62;
    &#60;/Result&#62;
    &#60;Result&#62;
    &#60;Parent ref&#61;&#34;lead4&#34;.&#62;
     &#60;Statement&#62;
      &#60;Label&#62;ascus clavate or cylindrical&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;TaxonName ref&#61;&#34;taxon1&#34;/&#62;
    &#60;/Result&#62;
    &#60;Result&#62;
    &#60;Parent ref&#61;&#34;lead2&#34;/&#62;
     &#60;Statement&#62;
      &#60;Label&#62;ascostoma uniloculate&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;TaxonName ref&#61;&#34;taxon4&#34;/&#62;
    &#60;/Result&#62;
    &#60;Result&#62;
    &#60;Parent ref&#61;&#34;lead2&#34;/&#62;
     &#60;Statement&#62;
      &#60;Label&#62;ascostoma multiloculate&#60;/Label&#62;
     &#60;/Statement&#62;
     &#60;TaxonName ref&#61;&#34;taxon5&#34;/&#62;
    &#60;/Result&#62;
    &#60;/Leads&#62;
  &#60;/IdentificationKey&#62;
</pre>
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For more information on defining taxon names using the &lt;TaxonNames&gt; element, see the topic <a href="taxonnames.html">Defining taxon names</a>. 
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Note that taxa can also be arranged into hierarchies. See the topic <a href="taxonhierarchies.html">Defining taxon hierarchies</a> for more information.
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&lt;Scope&gt; describes the taxon or set of taxa to which the description applies.
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The &lt;Result&gt; element may include a &lt;Subkey&gt; element, which points to another complete dichotomous key. This allows a main/subkey arrangement, for example a key to the genera of a family with results leading to a subkey identifying the species within each genus.
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<h4><a name="Example_2_4_4_2_Subkeys_within_S"></a> Example 2.4.4.2 - Subkeys within SDD dichotomous keys. </h4>
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<pre>
      &#60;IdentificationKeys&#62;
         &#60;IdentificationKey id&#61;&#34;key 1&#34;&#62;
            &#60;Representation&#62;
               &#60;Label&#62;Key to genera&#60;/Label&#62;
            &#60;/Representation&#62;
            &#60;Leads&#62;
               &#60;Lead id&#61;&#34;lead1&#34;&#62;
                  &#60;Statement&#62;
                     &#60;Label&#62;Inflorescence open and spreading&#60;/Label&#62;
                  &#60;/Statement&#62;
               &#60;/Lead&#62;
               &#60;Result&#62;
                  &#60;Statement&#62;
                     &#60;Label&#62;Inflorescence dense and spike-like&#60;/Label&#62;
                  &#60;/Statement&#62;
                  &#60;Subkey ref&#61;&#34;key 2&#34;/&#62;    (key to species of first genus))
               &#60;/Result&#62;
                                            . . . etc.

         &#60;/IdentificationKey&#62;
      &#60;/IdentificationKeys&#62;

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-- DonovanSharp - 01 Jun 2006
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