Pelonomus thomi

## Taxonomy

Anthostoma

Gastrozoa

Tentaclostoma

Neostoma

Myzostoma

**Pelonomus thomi**

***Pelonomus thomi*** (lit. "Thomas's mud-dweller") is a species of myzostome.

## Description

A mature *P. thomi* measured about two centimeters in height, possessing a muted-blue shell and various fleshy appendages that were of a dusty, organic white color. It had a pair of long sensory stalks, each of which was tipped with three eyes and was lined with vibration-sensitive setae, and located all around its mouth were six spiny feeding arms. On either side of the mouth was a long, tentacle-like gas-exchanging structure that functioned more or less equivalently to a gill. Behind the gills, and spread out along the sides of the body, were four pairs of broad, flipper-like limbs.

The sole large external orifice referred to as a “mouth” lead to both a simple stomach and a cavity containing the reproductive organs, and was used for taking in food, releasing gametes, and excreting waste. Along the flanks of a *P. thomi* were also, presumably, a series of about four pairs of excretory glands used to maintain the balance of salt and sulfur in its blood. Not many details are known about how these glands work in the myzostomes, specifically.

Members of the species *P. thomi* may have been partly or even entirely herbivorous, feeding on plants like the chemophytes growing along the bottoms of riverbeds and mudbanks. Though they may occasionally have been forced to come out onto dry land due to their variable habitats, they still had to quickly return to the water to stave off desiccation. *P. thomi* specimens often fell prey to larger creatures like the metaxypods.

At the time of *P. thomi*’s evolution, most of the the planet’s land was concentrated in the form of a single, massive supercontinent, all along the coasts of which the species presumably thrived. However, the later breaking-apart of the continent likely resulted in a similar separation of many *P. thomi* populations. In their hundreds of millions of years spent isolated from each other, these groups likely became genetically distinct enough to be considered their own species. The diversity of *P. thomi*’s descendants has yet to be explored further.

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					- ***Pelonomus thomi***
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 † = Extinct