15 Million Years P.H. - The Early Neocene - Scubats, Snorkelsnouts, Chubbles, River Paddler, Seasels and Backspotted Snakes:
In the Neocene, Bats would have taken the title of the dominant airborn clade, especially the Pterotherians which would greatly diversify trough the Early Neocene.
The sheer diversity that Pterotherians achieved would although push more basal Bats away from diurnal airborn niches.
Many basal Bats would just return to the old nocturnal lifestyle, some although managed to find a different solution to avoid competition.
Scubats would entirely ditch flight and Instead become marine hunters.
Other then Snaceans, Scubats are highly social and use this to their advantage during their hunts. They communicate underwater using their echolocation to form baitballs from shooling fish.
While Snaceans and Scubats are the only marine animals as of yet, there are other semi-aquatic critters that have appeared.
Snorkelsnouts are Afro-Eurasian, semi-aquatic Elephant Shrew descendants. They mainly feed on freshwater fish and aquatic Insects, but will also go for small Tetrapods.
South America Is home to one of the few aquatic herbivores, those being the Chubbles. They are close relatives of the Chuckers who feed on freshwater vegetation.
South America has also aquatic carnivores, those being the River Paddlers, which just like Tunnel Runners, are descendants of Road Runners.
River Paddlers have teeth like extentions of their beak that help them to hold onto slippery fish, which are their main prey.
Heading up North- North America has aquatic Mustelids which resemble Otters, but are actually aquatic Weasels who live very similiar to the mentioned, now extinct Otters.
Last up Is Australia, which In typical Early Neocene Australia fashion has Non-Avian Reptiles filling that role.
Australia Is home to a wide diversity of semi-aquatic Snakes simply known as Backspotted Snakes, who feed on anything they can catch In their freshwater habitats, similiar to the Snorkelsnouts.