Erster , Aktueller , Nächster und Neuster Artikel mit Artikelbild in je Kategorie

<?php
$postcat = get_the_category();
$catid = $postcat[0]->term_id;
$thispost = $post->ID;


$first = new WP_Query( array( 'posts_per_page' => 1, 'category__in' => array( $catid ), 'order' => 'ASC', 'orderby' => 'date' ) );
 if( $first->have_posts() ) : $first->the_post();
 echo "\n".'<span class="small first-chapter">';
 if( $thispost != $post->ID ) { 
  echo '<a href="' . get_permalink($post->ID) . '">' . get_the_post_thumbnail($post->ID,'thumbnail') . '</a>'; 
 } else { 
  echo 'showing the first'; 
 }
 echo '</span>';
 endif; wp_reset_postdata();
 
echo "\n".'<span class="small this-chapter"><a href="' . get_permalink($thispost) . '">' . get_the_post_thumbnail($thispost,'thumbnail') . '</a></span>';


$nextpost = get_next_post(true);
 echo "\n".'<span class="small next-chapter">';
 if( $nextpost ) { echo '<a href="' . get_permalink($nextpost->ID) . '">' . get_the_post_thumbnail($nextpost->ID,'thumbnail') . '</a>'; 
 } else { 
 echo 'there is no next'; 
 } 
 echo '</span>';
 
$latest = new WP_Query( array( 'posts_per_page' => 1, 'category__in' => array( $catid ), 'order' => 'DESC', 'orderby' => 'date' ) );
 if( $latest->have_posts() ) : $latest->the_post();
 echo "\n".'<span class="small latest-chapter">'; 
 if( $thispost != $post->ID ) { 
  echo '<a href="' . get_permalink($post->ID) . '">' . get_the_post_thumbnail($post->ID,'thumbnail') . '</a>'; 
 } else { 
  echo 'showing the latest'; 
 }
 echo '</span>';
 endif; wp_reset_postdata();
?>