pebbled butterflyfish
... that pebbled butterflyfish are aggressively territorial and will form pairs to protect their feeding area?
... that <b id="mwDF8"><a href="./Pebbled_butterflyfish" id="mwDGA" rel="mw:WikiLink" title="Pebbled butterflyfish">pebbled butterflyfish</a></b> are aggressively <a href="./Territory_(animal)" id="mwDGE" rel="mw:WikiLink" title="Territory (animal)">territorial</a> and will form pairs to protect their feeding area?