Antwort von Henri

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\usepackage{tabularx}\begin{document}\blindtext\begin{wraptable}{l}{8cm}\bfseries\renewcommand\tabularxcolumn[1]{m{#1}}\newcommand\italic{\normalfont\itshape}\begin{tabularx}{\linewidth}{|X | *{4}{Wc{.6cm}|}}\hline\rowcolor[HTML]{656565}\textcolor[HTML]{FFFFFF}{Surface geometry}&\multicolumn{4}{c|}{\textcolor[HTML]{FFFFFF}{Terrain Classes}}\\\hline\italic fine texture,\par high convexity
    &\cellcolor[HTML]{643403}1
    &\cellcolor[HTML]{F8A102}5 
    &\cellcolor[HTML]{009901}9  
    &\cellcolor[HTML]{34FF34}13
    \\\hline\italic fine texture,\par low convexity    
    &\cellcolor[HTML]{CE6301}3 
    &\cellcolor[HTML]{FFCC67}7 
    &\cellcolor[HTML]{34CDF9}11 
    &\cellcolor[HTML]{3531FF}15
    \\\hline\italic coarse texture,\par low convexity  
    &\cellcolor[HTML]{F007F4}2 
    &\cellcolor[HTML]{A34894}6 
    &\cellcolor[HTML]{C5C783}10 
    &\cellcolor[HTML]{FCFF2F}14
    \\\hline\italic coarse texture,\par low convexity  
    &\cellcolor[HTML]{F690E5}4 
    &\cellcolor[HTML]{F6C8EC}8 
    &\cellcolor[HTML]{DFE360}12 
    &\cellcolor[HTML]{FFFC9E}16
    \\\hline\multicolumn{1}{c}{}&\multicolumn{1}{c}{\makebox[0pt][c]{\italic steep}}&\multicolumn{2}{c}{}&\multicolumn{1}{c}{\makebox[0pt][c]{\italic gentle}}\end{tabularx}\end{wraptable}\blindtext\end{document}