If you love tardigrades, then you’ll love these newly discovered Mold pigs. These never-before-seen microinvertebrates were discovered in Dominican amber by a paleobiologist.
Mold pigs got their nickname due to their fungi-heavy diet and vague resemblance to hogs. Their scientific name is Sialomorpha dominicana, which means “fat hog-shaped” in Greek. These creatures are only 0.003 inches (100 micrometers) long. They have four pairs of legs, a flexible head and an exoskeleton that molts as they grow. Mold pigs were discovered by paleobiologist and entomologist George Poinar Jr. of Oregon State University.
Poinar said:
The mold pigs can’t be placed in any group of currently existing invertebrates — they share characteristics with both tardigrades, sometimes referred to as water bears or moss pigs, and mites but clearly belong to neither group.
Poinar actually inspired a major plot point in author Michael Crichton’s famous novel “Jurassic Park,” from a discovery he made from amber. Poinar and his wife Roberta Hess, an electron-microscopist, discovered that organisms can be perfectly preserved in amber. Amber is fossilized resin of ancient coniferous trees. An organism’s cellular machinery can remain largely intact over the course of millions of years within the hardened yellowish substance. When Crichton heard of this discovery his imagination ran wild and he dreamt up a world where dinosaurs could be summoned from DNA encased in amber.
Since then, Poinar never stopped searching for new organisms hidden in ancient resin. Where there’s a will, there’s a way. Now, most recently in the Dominican Republic, he and his colleague Diane Nelson of East Tennessee State University came across several hundred mold pig fossils coated in amber. The specimens date back as far as 30 million years (the mid-Tertiary period), which means they shared their habitat with pseudoscorpions, nematodes, protozoa, and fungi.
Poinar added:
The large number of fossils provided additional evidence of their biology, including reproductive behavior, developmental stages and food.
From these fossils, the researchers discovered that the creatures mostly fed on fungi but also ate some small invertebrates. They had no claws at the end of their legs as tardigrades or mites do. Mold pigs may resemble tardigrades at first glance but don’t be fooled, they actually represent a previously unknown new family, genus and species of microinvertebrate. Poinar and Nelson describe their discovery in a paper in the journal Invertebrate Biology.
Poinar explained:
Based on what we know about extant and extinct microinvertebrates, S. dominicana appears to represent a new phylum. But we don’t know when the Sialomorpha lineage originated, how long it lasted, or whether there are descendants living today.
As Poinar never stops searching for new organisms in ancient resign, it makes you wonder what he will find next!
