They remained unnamed in the film but Screenrant tried to identify them:
Although Riot escaped, a number of symbiote samples were still obtained by the Life Foundation. This yellow symbiote is probably Phage, who's traditionally presented as a yellow/orange. Phage doesn't survive the Life Foundation's experiments.
The other symbiote alongside Riot, Scream and Phage is a blue and gold one, which - as initially shown in the Venom trailer - was set loose on unwitting test subjects. Not only is this coloring distinct from the others in the film, it also doesn't match up with any of the Five Symbiotes from the comics (Riot has a blue-ish tint but, as established, here is more pure silver). It looks to be the Toxin symbiote, a better-known character than any of the Five - and, ironically, in the comics the only symbiote to become a trusted superhero ally of Spider-Man.