Dwarf sperm whale Kogia sima

Kogiopsis floridana was a physeteroid whale that lived near the coast of the southeastern United States from the mid-Miocene to the early Pliocene, about 14-4 million years ago.

Known just from fossilized lower jaws and teeth, with some teeth up to nearly 13cm long (~5"), its full life appearance and size are uncertain – but it may have been slightly larger than a modern bottlenose dolphin at around 4.5m long (~14'9"). It's traditionally been considered to be part of the kogiid family, closely related to modern pygmy and dwarf sperm whales, but some studies disagree with that classification and instead place it in the true sperm whale lineage.

It was probably a predator in a similar ecological role to modern orcas, adapted for hunting prey like squid, fish, and smaller marine mammals. But unlike orcas it wouldn't have been the apex predator of its ecosystem, subject to predation pressure by even larger carnivores like macroraptorial sperm whales and everyone's favorite ridiculously huge shark – and as a result it probably had a "live fast and die young" lifestyle similar to modern kogiids and other small-to-medium-sized Miocene physeteroids, rapidly maturing and only living to around 20 years old.

I've reconstructed Kogiopsis here as a kogiid-like animal, with a similar sort of shark-like head shape and "false gill" markings. In the background a second individual is depicted displaying "inking" behavior, releasing a defensive cloud of reddish-brown fluid from a specialized sac in its colon.

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Genus Kogia - the little Sperm whales

And another infographic. I’m really liking this way of showing off work, feels a bit more visually appealing than just bare illustrations. This time it’s the turn of the mini sperm whales. Even though they look somewhat similar to Sperm whales, they are in a separate family, Kogiidae. It’s interesting how often they strand, given their low sighting rate at sea. They may simply be overlooked or misidentified: they tend to keep a low profile, and aren’t very demonstrative (though Dwarf sperm whales occasionally breach).

Kogiopsis

Kogiopsis — рід середньоміоценових китоподібних із родини Kogiidae. У нього були дуже довгі зуби без коренів, довжиною 3–12,7 см. Ці зуби зустрічаються переважно у Флориді та Південній Кароліні. Крім зубів, когіопсис відомий насамперед по нижньощелепним кісткам. Анатомія зубів і нижньої щелепи схожа на анатомію вимерлого роду кашалотів Orycterocetus.

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Dwarf sperm whale (Kogia simus)

The dwarf sperm whale inhabits temperate and tropical oceans worldwide, in particular continental shelves and slopes. It was first described by biologist Richard Owen, in 1866. The species was considered to be synonymous with K. breviceps from 1878 until 1998. Its appearance is very similar to the K. breviceps, distinguished mainly by the position of the dorsal fin on the body, which is nearer the middle on K. simus. The dwarf sperm whale is a suction feeder that mainly eats squid, and does this in small pods of typically 1 to 4 members. It is preyed upon by the killer whale and large sharks such as the great white shark. When startled, the whale can eject a cloud of red-brown fluid, similar to a squid. The dwarf sperm whale is hunted in small numbers around Asia. It is more threatened by ingesting or getting entangled by marine debris. No global population estimate has been made, and so its conservation status by the IUCN is data deficient.

Classification Animalia - Chordata - Mammalia - Eutheria - Boreoeutheria - Laurasiatheria - Scrotifera - Euungulata - Artiodactyla - Artiofabula - Cetruminantia - Whippomorpha - Cetacea - Odontoceti - Physeteroidea - Kogiidae - Kogiinae - Kogia - K. simus

Pygmy sperm whale Kogia breviceps

Observed by bikingbirder, CC BY-NC

Dwarf sperm whale Kogia sima

Dwarf sperm whale Kogia sima