Phyllocaudia

**Plyllocaudia**, commonly known as **scritters**, are a class of bilateral sidobiosians distinguished by their rubbery "leaf lobes" which form a cape-like structure on their backs. Aside from those in the order Phylloacrotiriformes, they are predominantly very small, often no bigger than 10 centimeters in length.

## Evolutionary History

The ancestors of scritters split off from other sungrazers long before they gained their characteristic traits. They became bilateral in order to support increased motility to escape predators, and they developed a somewhat cnidarian-like digestive system to help get the energy they needed to support this lifestyle. The rubbery "leaf lobes" most likely developed so that the photosynthesizing surface would remain stable and not so easily tear even while fleeing from predators, while their digits and claws likely developed for traction.

The ancestral state of scritters is for males to broadcast spores to be collected by females, but members of the subclass Viscosiova developed a more optimized mating method involving direct mouth-to-mouth copulation.

Jawed scritters (order Phylloacrotiriformes) are a relatively recent development from the past 50 million years. Their jaws are modified forelimbs, which had already been in use for shoving food into their mouths in their closest relatives.

## Shared Biology

### Skeleton

Scritters retain cartilaginous skeletons, and their bone armor is limited to their claws where it is covered with a cellulose sheath to protect it from damage. The cellulose sheath is unusually tough, having a surprisingly strong chitin-like structure behind it.

### Photosynthesis

Their backs are covered by what is, essentially, a rubbery leaf which is also a part of their body. The leaf consists of 6 "leaf lobes". The kind-most lobe forms a sort of leaf-tail of varying length which can serve a variety of purposes, such as balance, display, and simply aiming at the sun. The two pairs of lateral leaf lobes mainly serve to increase surface area for photosynthesis, and the front-most lobe is modified for a myriad of purposes.

### Pigmentation

Scritters must have chlorophyll because of their photosynthetic nature. However, they also have access to anthocyanin, which can create purple markings which do not interfere with photosynthesis. As such, many species are actually purple or have purple markings over their innate green coloration.

### Eyesight

Scritters have one pair of camera eyes which can see in color. They cannot see red, but they can see a little bit into the ultraviolet spectrum. As their body plan is poorly suited to having a neck, some scritters have mobile eyestalks.

### Digestive System

Scritters are somewhat "behind" compared to a lot of organisms in their environment due to them having to evolve a digestive system from scratch. They do not have a thru gut, and anything they cannot digest must be regurgitated the same way it came in.

Members of the order Phylloacrotiriformes have jaws derived from their forelimbs, which allow them to capture and process food more effectively

### Reproductive System

Basal scritters spawn using airborne pollen-like spores, which are collected by females and used to fertilize eggs which grow on their leaves. Members of the subclass Viscosiova instead store their eggs and spores in their mouths and copulate by kissing; their eggs are often sticky, and they can be placed up high so that they remain exposed to sunlight.

Scritter eggs do not contain very much yolk. Developing offspring depend on sunlight, and as such the eggshells are transparent or tinted purple with anthocyanin to let in as much red and blue light as possible. Ancestrally, scritter hatchlings are near-radial with only their eyes betraying their eventual bilateral nature. However, many different branches of the scritter lineage evolved more developed hatchlings secondarily.

### Respiration and Circulatory System

Scritters have passive respiration through stomata-like pores. Being active, they do require oxygen, but being phototrophs they can also produce their *own* oxygen. As such, they are not affected as much by varying oxygen levels compared to other organisms with passive respiration, but they also have little evolutionary pressure to ever improve their respiration.

They have a closed circulatory system and 6 hearts arranged in a ring, which pumps violet blood throughout their bodies. Their blood uses a violet blood pigment to carry oxygen for use in their active lifestyle, while carbon dioxide, mainly being used on the outside of their body, is simply obtained from the atmosphere and transported cell to cell as needed. Notably, their violet blood pigment allows red and blue light which is not caught by their chlorophyll to be reflected back into their photosynthetic cells, boosting their ability to thrive in dimmer lighting conditions.

## Examples

* Subclass Sporova (scritters which use spores)
	+ Order Altafolioformes
		- Winged Leafdrake - unambiguously flightless arboreal predators
* Subclass Viscosiova (scritters which mate by kissing)
	+ Order Arripilingua
		- Lancecrawler - small detritivores of the steppe
		- Broadcape - arboreal herbivores
	+ Order Phylloacrotiriformes (jawed scritters)
		- Leafcapers - various jawed lizard- and rodent-like species