It becomes paraphyletic
Step-by-step explanation:
Any community of species given a formally taxonomic title is a taxon (pl. taxa). Broadly, a monophyletic taxon contains an organism community from a common ancestor, while a multifyletic taxon consists of unconnected organisms from more than one forefather.
The broad meaning of fish, for example, is one of those concepts that include mammals including whales, and also sharks, salmon or scaled shrimp, of which ancestral vertebrates are often the common relatives, through which amphibians and reptiles come.
Referencing a group of species as a paraphyletic group means that some biological group members have also been positioned in another group for whatever reason.