A recent discovery within the coleiod cephalopod species has further pushed back its known origin by approximately 82 million years, making it the oldest known vampryopod. Research recently published in the online Nature Communications journal has identified a distinctively well-preserved specimen that displays two arms more than the usual eight that are commonly associated with most octopods, vampyropods, and cephalopods known today.
Considered extremophiles, or any organism able to thrive in environments considered extreme, vampyropods were originally thought to be part of the Octopi taxonomy due to having both squid and octopi traits. Lacking the two required arms to appear as the traditional image of the squid, it is a common confusion. Evolution has kept most of these physical characteristics unaltered over millennia.
Discovered in Montana in 1988, this specimen marks the most complete fossil of the species. Fossilized samples of these species are rare due to their being soft-bodied and internally shelled. This internal shell is known as a gladius. Although this trait has been observed early on in the fossil record, it wasn't always a part of the vampyropod or cephalopod morphology. A mineralized layer of the interior shell appears to have projected anteriorly, creating what is now the gladius. The fossil shows that vampyropods subsisted with a gladius during the Mississippian era.
The genus was given the name Syllipsimopodi bideni after the Greek word for “prehensile” and “foot”. It appears to have been one of the earliest of the cephalopods to adapt and grow suckers. The longer tentacles were discovered to have been similar to the other four pairs, with the length being the primary difference.
The discovery pushes the boundary for what we understand of the fossil record today in terms of octopi and squid and their evolution over the millennia. Scientists have interpreted the two long arms of most cephalopods as filaments, similar to vestigial arms. Contiguously, this trait has not undergone much, if any, evolution and has remained a significant identifiable characteristic.
According to the Division of Paleontology within the American Museum of Natural History, all ten arms are preserved with suckers, which strengthens a previous argument had by scientists regarding its common ancestor. These adaptations are representative of wanting to have more precise predation. In the case of this vampyropod, the tentacles with suckers in combination with the gladius align the Mississippian fossil with the extant squids of today.
Due to their highly well-defined niche characteristics, these squids have remained almost unchanged for hundreds of millions of years. Although the fossil record is incomplete, what is understood is the initial greenhouse gasses that produced environmental change millions of years ago created the environmental conditions perfect for the evolution of invertebrates and what we know today. The Great Barrier Reef is also responsible for creating the environment that has maintained the mysterious and much-undiscovered marine world wherein the cephalopods and vampyropods alike reside—just waiting for biologists and paleontologists to study them.
Sources, Science Daily, Natures Communications, National Ocean Service
