Horseshoe crabs have been around for 450 million years, but it's a more recent fellow, which dates back to the late Triassic, and has now stolen the show.
Researchers at the New Mexico Museum of Natural History and Science (NMMNHS) in Albuquerque have come across a 245 million-year-old fossil belonging to an extinct species of horseshoe crab.
What makes this particular find so exciting and rare, apart from the scarcity of horseshoe crab fossil records, is its uncanny resemblance to the infamous Darth Vader.
Horseshoe crab fossils are notoriously difficult to come by, so they "are often new to science" whenever they pop up. This strange fossil takes the cake, as it displays a long tail and a big head shield, shaped like the letter "D," which conspicuously looks like Vader's helmet.
For this reason, the scientists chose to name the newfound species of horseshoe crab Vaderlimulus trickiafter the notorious "Star Wars" villain.
Vaderlimulus is the first North American fossil of a horseshoe crab to ever be unearthed from rocks of this age, coming all the way from the Triassic Period, the museum mentioned in a news release.
The Vaderlimulus fossil was discovered near Paris, Idaho, and it was presented to the world last week in a study published by the prestigious journal, Neues Jahrbuch für Geologie und Paläontologie, the oldest paleontological publication worldwide."The fossil record of horseshoe crabs (Xiphosurida) from the Mesozoic of North America consists of only three name-bearing specimens from the Cretaceous. We add to this depauperate record the first report of a horseshoe crab body fossil from the Triassic of North America," the authors wrote in their paper.
In their opinion, Vaderlimulus most likely lived in the shallow waters on Idaho's coastline (back when Idaho had a coastline) and probably belonged to the extinct family of Austrolimulidae.
Study authors Allan J. Lerner and Spencer G. Lucas, both from NMMNHS, together with colleague Martin Lockley from the University of Colorado at Denver, reached this conclusion by analyzing the fossil's bizarre features.This hypothesis could explain Vaderlimulus' "unusual body proportions that give it an odd appearance," as Lerner points out, considering that the Austrolimulidae family was going through a series of "body modifications" during the Triassic.
While dinosaurs and mammals were just starting their evolutionary development, "horseshoe crabs were already ancient" by the time the Triassic rolled around, disclosed the NMMNHS. At the time, the marine-dwelling Austrolimulidae were expanding their horizons and trying to conquer freshwater settings. This required evolutionary adaptations that could account for their "bizarre appearance by modern standards," as mentioned in the news release.
Ancient and undoubtedly resilient, having survived five mass extinctions, according to Newsweek, horseshoe crabs aren't technically crabs. Instead, they are more closely related to scorpions and spiders. With these arachnids, the horseshoe crabs share a common physical trait, namely their hard exoskeleton. These critters are truly "living fossils" and haven't changed much since they first dawned on the planet. Even modern-day horseshoe crabs still sport their eyes on the top, and they have their legs safely tucked under their wide shells, which sparked the Darth Vader comparison for Vaderlimulus.
In the news release, the museum notes that there are only four surviving species of horseshoe crabs alive today. Popular Science notes their numbers are continuously dwindling, as horseshoe crabs are washing up on beaches by the hundreds for inexplicable reasons. Furthermore, their rare blood contains a valuable chemical and is often harvested by the medical industry, which explores its uses in the manufacture of life-saving treatments, Quartz reports.