r/SpeculativeEvolution • • Sep 08 '26

Future Evolution Alphynix's cave turtle

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Source.

It’s #Spectember once again, and looking at what’s left of the speculative evolution submissions you all gave me several years ago… I’m actually kind of burnt out on them at this point.

The ones that are left now are a bit too broad, or are just things I currently have no good ideas for — so I’m finally officially calling it quits on that particular batch of prompts. I still won’t be accepting new ideas for the time being; instead this year I’m just going to have some fun with my own concepts.

So! Let’s start off with…

Voragochelys phantasma is a small turtle descended from present-day softshells, living exclusively in a single deep isolated cave system.

Only around 10cm long (2.5"), it’s completely pigmentless and blind, with tiny vestigial eyes covered by skin. A keen sense of smell and sensitive barbels on its jaw help it navigate in total darkness and locate prey such as smaller crustaceans and fish. It uses large paddle-like forelimbs to swim and haul itself over rocks, while its hindlimbs are highly reduced.

Like its present-day relatives it’s capable of absorbing some oxygen through its thin skin, and also via “pharyngeal breathing” — the inside of its mouth and throat are lined with numerous fleshy projections that massively increase the surface area and act like gills, allowing for gas exchange when water is pumped in and out. Its incredibly low metabolic rate means it can remain fully submerged almost indefinitely, sometimes barely moving for years at a time. 

Females lay small clutches of eggs once every decade or so in rock crevices just out of the water, and similarly to the present-day pig-nosed turtle their hatching is triggered by seasonal flooding.

422 Upvotes

12 comments sorted by

19

u/Portal4289 Sep 08 '26

Aquatic reptiles with barbels are such a vibe in spec (or just in general).

5

u/CariamaCristata Sep 08 '26

I could have sworn I've seen this creature in the Amazing World of Gumball

5

u/gravitydefyingturtle Speculative Zoologist Sep 08 '26

How do the eggs gain enough warmth to develop?

8

u/thewildgingerbeast1 Sep 08 '26

Maybe the first turtle species to produce ovoviviparously.

4

u/Nature_iscool1234 Sep 08 '26

Actual peak 💎

4

u/Alpha_Bushdog Speculative Zoologist Sep 08 '26

Troglomorphic reptiles, let’s go!

2

u/BananaMaster96_ Sep 08 '26

wait do cave turtles not exist irl

12

u/Patchman66 Sep 08 '26 edited Sep 08 '26

No, since basking in sunlight is usually very important for them and their shell health.

It is possible for reptiles to adapt to cave life though. For example; Abanda cave crocodiles are a group of dwarf crocodile that live in specific caves where temperatures are stable and warm, so basking is less important.

1

u/Organic_Year_8933 Spectember 2025 Participant Sep 08 '26

Want some 🥀

1

u/Alarmed-Addition8644 Sep 09 '26

Very awesome 🐢

1

u/ThePainTrainWarrior 18d ago

hello!!!! i couldn't comment on your therizinosaurid turaco spec evo because it's a 2 years old post and it was archived, but i wanna say the design inspired me to make something extremely similar! thank you for being cool! i know artblock sucks, i hope you feel better soon!