    Anguilla                    &lt;NA&gt;</span></span>
<span><span class="co">#&gt; 2                 1 Scardinius erythrophthalmus                    &lt;NA&gt;</span></span>
<span><span class="co">#&gt; 3                 1      Gobiomorphus breviceps                    &lt;NA&gt;</span></span>
<span><span class="co">#&gt; 4                 1        Galaxias brevipinnis                    &lt;NA&gt;</span></span>
<span><span class="co">#&gt; 5                 1       Salvelinus fontinalis                