<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>2007-4298</journal-id>
<journal-title><![CDATA[Botanical Sciences]]></journal-title>
<abbrev-journal-title><![CDATA[Bot. sci]]></abbrev-journal-title>
<issn>2007-4298</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Botánica de México A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2007-42982021000100182</article-id>
<article-id pub-id-type="doi">10.17129/botsci.2696</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Pollen morphology of the Megamexican cycads reveals the potential of morphometrics to identify cycad genera]]></article-title>
<article-title xml:lang="es"><![CDATA[La morfología del polen de las cícadas de Megaméxico revela el potencial de la morfometría para identificar los géneros de cícadas]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vovides]]></surname>
<given-names><![CDATA[Andrew P.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Guevara]]></surname>
<given-names><![CDATA[Roger]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Coiro]]></surname>
<given-names><![CDATA[Mario]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Galicia]]></surname>
<given-names><![CDATA[Sonia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Iglesias]]></surname>
<given-names><![CDATA[Carlos]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Instituto de Ecología, A.C. Red de Biología Evolutiva ]]></institution>
<addr-line><![CDATA[Xalapa Veracruz]]></addr-line>
<country>Mexico</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,University of Fribourg Department of Biology ]]></institution>
<addr-line><![CDATA[ Fribourg]]></addr-line>
<country>Switzerland</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Jardín Botánico Fc. J. Clavijero  ]]></institution>
<addr-line><![CDATA[Xalapa Veracruz]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>03</month>
<year>2021</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>03</month>
<year>2021</year>
</pub-date>
<volume>99</volume>
<numero>1</numero>
<fpage>182</fpage>
<lpage>197</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2007-42982021000100182&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2007-42982021000100182&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2007-42982021000100182&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  Background:  Although pollen morphology has always been an important tool in plant systematics, the possibility of distinguishing between related taxa is still debated. A difficult case is the cycads, where their morphology and small size is very similar. Pollen morphology has been important in plant systematics and determination at the species level is possible depending on the group. Controversial cases are the cycads, where their small pollen and smooth sculpture when observed under light microscopy present few useful characters for separation at the species level.  Question:  Will cycad pollen morphometry be useful to distinguish taxa?  Study species:  15 species within the genera Ceratozamia, Dioon and Zamia were investigated with five species of each genus.  Methods:  Pollen was obtained from both live specimens from the Clavijero Botanic Garden of the Instituto de Ecología, A.C., as well as herbarium specimens. Acetolyzed pollen was used for descriptions and morphometry, and non-acetolyzed pollen for MEB images.  Results:  The thickness of the exine and pollen sculpture of Dioon differed from that of Ceratozamia and Zamia thus allowing its identification. The pollen morphology of Ceratozamia and Zamia is very similar and therefore difficult to distinguish between species.  Conclusions:  The thicker exine of Dioon allows its pollen to be distinguished from the other two genera. Morphometric methods must be applied to distinguish pollen between species of Ceratozamia and Zamia.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Antecedentes:  Aunque la morfología del polen siempre ha sido una herramienta importante en la sistemática de las plantas, todavía se debate la posibilidad de distinguir entre taxa relacionados. Un caso difícil son las cícadas, donde su morfología y tamaño pequeño es muy parecido. La morfología del polen ha sido importante en la sistemática de las plantas y la determinación a nivel de especie es posible dependiendo del grupo. Casos discutibles son las cícadas, donde su polen pequeño y su escultura lisa cuando se observan bajo microscopía óptica presentan pocos caracteres útiles para la separación a nivel de especie..  Pregunta: ¿Será útil la morfometría del polen de las cícadas para distinguir taxa?  Especies de estudio:  Se investigó 15 especies dentro los géneros Ceratozamia, Dioon y Zamia con cinco especies de cada género.  Métodos:  Se obtuvo polen tanto especímenes vivas del Jardín Botánico Fco.J. Clavijero del Instituto de Ecología, A.C., así como especímenes de herbario. Se utilizó polen acetolizado para las descripciones y morfometría, y polen no acetolizado para imágenes SEM.  Resultados: El grosor de la exina y escultura del polen de Dioon diferió del polen de Ceratozamia y Zamia así permitiéndo su identificación. La morfología del polen de Ceratozamia y Zamia es muy similar y por lo tanto difícil de distinguir entre especies.  Conclusiones: La exina más gruesa de Dioon permite distinguir su polen de los otros dos géneros. Para distinguir el polen entre especies de los géneros Ceratozamia y Zamia es necesario aplicar métodos morfométricos.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Cycadales]]></kwd>
<kwd lng="en"><![CDATA[Mexico]]></kwd>
<kwd lng="en"><![CDATA[pollen morphology]]></kwd>
<kwd lng="en"><![CDATA[taxonomy]]></kwd>
<kwd lng="en"><![CDATA[Zamiaceae]]></kwd>
<kwd lng="es"><![CDATA[Cycadales]]></kwd>
<kwd lng="es"><![CDATA[México]]></kwd>
<kwd lng="es"><![CDATA[morfología de polen]]></kwd>
<kwd lng="es"><![CDATA[taxonomía]]></kwd>
<kwd lng="es"><![CDATA[Zamiaceae]]></kwd>
</kwd-group>
</article-meta>
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