Introduction to Extant Fauna

Sagan 4 is home to many groups of fauna both living and extinct, and for a newcomer just starting to explore its diverse array of biota, knowing where to start can be difficult. This guide serves to introduce each major group of living fauna on Sagan 4.

Plents
Plents have historically made up a significant portion of Sagan 4's biota. A sort of "planimal", many species are both motile and capable of photosynthesis using a pair of large, mobile leaves. Many species have repurposed their leaves for swimming, flight, or thermoregulation, with or without retaining photosynthesis, while some have lost them completely.

Skuniks
Unlike most sea plents, modern skuniks are terrestrial and walk on 6 legs usually supported by an exoskeleton. They are also among the few major groups of plents to have a through gut, rather than a blind gut.

Walking Plents
Walking plents are, surprisingly, a sister group to the sea plents rather than a clade within them. Walking upon four legs supported by flexible "wooden bones", walking plents have historically constituted much of Sagan 4's megafauna.

No-Plents
No-plents are the earliest-diverging major group of walking plents characterized by a superficially mammal-like profile and, in some species, an extra pair of eyes. Most modern species are fairly small and herbivorous. Living types of no-plent include nodents, ketters, and nobits.

Flying Plents
Flying plents are among the few modern walking plents to mostly retain large, functional leaves, not because they are dependent on photosynthesis, but because they use them to fly. Incredibly diverse, flying plents make up a significant portion of all plents living or extinct and feed on a myriad of different food sources.

Most modern species of flying plent are specifically phlyers, which are also the only living group to retain flight. Related to them are the emulsechoes, the sprinters, and the bandersnatches, which each lost flight independently.

Worms
Contrary to their name, worms are some of the most complex fauna on Sagan 4. An ancient symbiosis of animal- and plant-like cells, worms are known for their two distinct cell types, the fleshy "red cells" which make up their "meat" and the rigid "green cells" which have cell walls and originally formed a living exoskeleton.

Marephasmatises
The radially symmetric jelly-like carpozoans are, in the modern day, represented only by the stinging rainbow marephasmatises.

Spondylozoans
Spondylozoans are the vertebrate-like side of carpozoa which bear an internal skeleton and constitute some of Sagan 4's megafauna. Though similar to Terran vertebrates, they commonly have 6 eyes, and terrestrial forms have unusual shoulder-like hip anatomy.

Caudopods
Caudopods are a terrestrial branch of spondylozoa which are named for their ancestral locomotion which involved walking on the tail. Originally the reptile-like grade to snappers' amphibia, today they are represented mostly by therapsid-like forms.

Limblesses
Limblesses represent a distinct branch from other terrestrial spondylozoans, closer to snappers than to caudopods, which lost all of their limbs.

Fee
Fee (singular: foi) are unique among Sagan 4's fauna in that they consist only of a single, highly complex cell.