Cerest: Drecu full body by Blasho on DeviantArt (original) (raw)

OOOUUGHHHHHH I’m BACK !! Here’s some bug lizards

Their blood uses two iron-based carriers: chlorocruorin in transport cells and hemerythrin that floats free in the bloodstream, which respectively gives their blood a green and/or purple color. As their ancestors got bigger and evolved an active respiratory and circulatory system as opposed do just having spiracles/air sacs, they also started using a secondary blood chemistry to support their original, single one. The hemerythrin works across a general range of temperatures and oxygen concentrations, widening the range of environments they can live in, but despite the cooperative binding with each other it’s very inefficient. Thus, it takes a lot of effort and resources for them to use it, part of the reason behind their relentless expansion into new territory for new food sources etc (their body functions like metabolism will slow down and speed up accordingly, and they’re able to strip pretty much every bit of energy form the stuff they eat due to a highly effective digestive system, but due to the limited ability to store fats for later and difficulty in breaking down their own muscles for energy without collapsing their whole skeleton, them coping with scarcity essentially means going into a coma.) Despite this, it comes with the added benefit of giving them better and faster cell regeneration and healing (through the Bohr effect and because of its potency as an immune effector), as well as immunity to carbon monoxide poisoning (due to its low affinity for that molecule, which is helpful since chlorocruorin has a high affinity for it, which helps prevent excess buildup. They also convert any access CO into material for their shells and scales. ) and nitrogen stress/decompression sickness (again, low affinity etc). The chlorocruorin helps them in the cooler and low oxygen environments where they originated, and in mitigating the resource cost of relying more on hemerythrin while still benefitting from it. It also needs support from the hemerythrin when anywhere too hot (where there are more resources, and where the heat helps them with sustained activity/not wasting resources on body heat, and gives them freedom to live anywhere in the wide temp range on their original planet ). So, they are perfectly fine in cold environments and environments where humans would be fainting from too little oxygen, but could run into problems if things get too hot (as opposed to Kixeli, who have problems when things get too cold even though their blood pigment works better at cooler temperatures, because they’re entirely exothermic and evolved more reliance on the ever-present heat on their home planet for making their body functions more efficient)

Their silly little expensive metabolism makes food a very effective tool for leaders to keep under classes subservient, since it’s pretty easy to control people who rely on you to keep them functioning, and their thoughts also tend to slow to a crawl without the necessary energy. Stratifying resources also gives a distinct physical difference between classes, with brighter colors and more developed/larger shell size being indicators of the upper ranks . Their tails, for example, are made from the hardened tube remnants of the segments of their abdomen chamber when they were larva and prepupa. With enough nutrients throughout their teenage molts, it will spread out those 4 main internal segments with the outer shell and more muscle into a longer or thicker tail. Without, it will be shorter and thinner since the segments themselves are smaller and closer together (in some cases staying the same length as their prepupa size since they need it closer for their more limited muscle and shell to hold onto.) The smaller tails alongside their paler colors also gives under classes a more child-like and therefore disreputable and subservient look, furthering the divide.

I’ve also been thinking about their endo-exo skeleton thing- it’s still a thing of course but here’s some more info. they have plates that range from hard and thick to thin and flexible that make up a segmented outer shell that is present over all their body. It is what they molt and is primarily used for muscle attachment in their limbs, but it mostly just covers the rest of their body elsewhere. This is because they also have a disconnected internal tube and chamber system mainly in their head, tail, neck, and torso for more places for their muscles to attach to while maintaining that bipedal stance and organ placement. They don’t/can’t replenish these through a molting process, and instead they’re maintained from the inside more like our bones. The rest of their body grows and shrinks around them (though limited by the outer shell on top). In between the shell and the internal structures, they also have a thin skin/scales layer, which can be seen best joining the gaps between the hardest and most prominent parts of their outer shell as it covers the thinner plates underneath (some places on their abdomen, the underside of their tail, the front of their neck, and several places on their face. ) This is derived from the chrysalis layer that they grew, and when they emerge it softens and wraps them. As it dries, it dies everywhere except the edges/gaps of the outer shell, where it stays somewhat vascularized as it attaches to the edges while the outer shell is still hardening . This layer allows for fat storage under it and prevents everything from slipping out when they molt in areas where the outer shell isn’t actually attached to anything/ is not fully encapsulating on its own. they shed this every so often after a new one grows from underneath to replenish it since the blood flow isn’t great. Molting becomes very infrequent after pupation, usually only happening perhaps 2-3 times (maybe 4 for Rox) in their teenage years until they stop growing. It only happens as an adult due to extreme changes in size (for example, moving up to a reproductive position can cause an increase in size from the hormones, particularly in Rox, which can trigger a molt of the outer shell to make room.) all this inner and outer latticing is mainly just the result of them evolving from something that used to have an exoskeleton, somewhere along the way this nonsense happened. It doesn’t actually weigh that much because it’s mostly made from lightweight but strong and durable carbons.

I’m posting a rough drawing of what the hell im trying to say about their endo/exo skeleton in posts, so look at that if you want. I’ll def be thinking about how it actually “works” more, but the idea is the same and they’ll look the same regardless.

There’s only Sundyne to go now, and I’m also going to try and do one for muttreazik too (since the stuff I’ve posted for them before is HELLA crusty now XD ) eventually I’ll do some stuff about humans, one of these days….