‘Large’-mouthed sea creature on sale at market in Vietnam turns out to be new species
Walking through a busy market in Vietnam, scientists scanned the stalls for a very specific “large”-mouthed fish — but they weren’t shopping for dinner.
They were in the process of discovering a new species.
For over a century, experts in east Asia debated whether some “commercially important” longtooth grouper fish were one species or two, an important distinction for evaluating the animal’s population size and conservation status, according to a study published Nov. 25 in the peer-reviewed journal Species Diversity.
Experts went back and forth, describing two species and then recombining them. Local common names, misspellings and “deformed” scientific diagrams only added to the confusion, the study said.
Hoping to finally settle the 165-year-long debate, researchers collected dozens of groupers from the South China Sea, analyzed their DNA, scrutinized their appearances and reviewed old records. Slowly, a pattern emerged.
The groupers from the South China Sea and the East China Sea were subtly but consistently different. Researchers soon realized they’d discovered a new species: Epinephelus randalli, or the mud grouper.
Mud groupers can reach over a foot in length, the study said. Their bodies are “elongate” and covered in “small” scales. Their heads have a “large” mouth with “sharply pointed,” “canine-like” teeth.
A photo shows the pale pinkish brown coloring of the new species. Faint brown bands run down its sides, and a spiky fin runs along its back.
Mud groupers live off the coast of Vietnam, China and southern Taiwan. Longtooth groupers — the other commonly misidentified species — live off the coast of northern Taiwan, South Korea and Japan, the study said.
Researchers said they named the new species “randalli” after John E. Randall, a “distinguished ichthyologist … who passed away in 2020.”
A 2017 YouTube video from For 91 Days Travel Blog shows the Ha Long fish market in Vietnam where researchers found several mud groupers.
The new species was identified by its DNA, fins, scale pattern and body markings, the study said.
The research team included Kouichi Hoshino, Hiroshi Senou and Quân Văn Nguyễn.
This story was originally published December 2, 2024 at 8:06 AM with the headline "‘Large’-mouthed sea creature on sale at market in Vietnam turns out to be new species."
