TEMPO.CO, Jakarta – A team of biologists from Japan and the Philippines have identified three species new gobies, which belong to the genus Lentipes. The findings are described in a study published in the journal Systematics and Biodiversity on Tuesday, October 5, 2021.
One of the newly discovered species lives in the Philippine archipelago of Palawan and has been given the Latin scientific name Lentipes palawanirufus, which means lentipes. gobi Palawan red. Two other new species were discovered on Okinawa, a sub-tropical island in Japan, and were named Lentipes kijimuna and Lentipes bunagaya.
Ken Maeda, author Education who is also a scientist at the Marine Eco-Evo-Devo Unit, Okinawa Institute of Science and Technology Graduate University (OIST), said the name was inspired by Kijimuna and Bunagaya, wood spirits in Okinawan folk mythology who are usually depicted as having red hair or skin. “As their names suggest, these two new species have red markings on their bodies,” he said.
Lentipes kijimuna was the first species to be discovered in 2005, when Maeda discovered an alien-looking male gobie while conducting field research for his Ph.D. at the University of the Ryukyus, Japan. He said he was surprised to see his head and lower body were glowing red.
“The shape is similar to Lentipes armatus which until now was the only known species of Lentipes in Japan, but the color pattern is completely different,” said Maeda.
Color pattern is an easily observed characteristic, but the relationship between body color and species is not clear. In some cases, two different species of fish can look identical in color patterns, but other times, fish of the same species can show a lot of variation in color patterns known as color morphs.
To find out if this fish is just a rare color morph of Lentipes armatus, or a new species altogether, researchers will need to examine its DNA extensively. But first, they need more specimens.
It wasn’t until 2010, after joining OIST as a researcher, that Maeda found three more male fish in Okinawa with the same unique red coloration and collected one of them for further research. Then in 2012, he made another discovery—a second color morph, also male. This one has two red bands on the lower body.
During a survey of freshwater fish in Palawan from 2015-2018 in a collaborative project between OIST and Western Philippines University, Maeda found males exhibiting a third color variation. With a bright red head and reddish-brown underside.
After collecting sufficient samples, Maeda and colleagues uncovered the evolutionary relationships between fish with different patterns. They analyzed all of the mitochondrial DNA, and then looked at specific locations throughout the genome, including the nucleus.
The researchers found no differences in DNA from mitochondria, but did find that small changes in DNA across the genome separated the fish into four distinct species, according to their color patterns. “We thought this fish must have diverged recently, so the mitochondrial genes didn’t have enough time to mutate,” said Hirozumi Kobayashi, a Ph.D student at the University of the Ryukyus who analyzes nuclear DNA.
Maeda also confirmed that the fish looked different in body shape and color pattern from the 19 known Lentipe species in the world.
The researchers believe that the distinct color patterns of Lentipes males played an important role in maintaining their separate lineage. The team also reported that during intercourse, males exhibited brighter colors than usual and exhibited special behaviors that accentuated their specific color patterns when approaching females.
“Females may not accept males from other species with different color patterns, although more research is needed to verify this,” the study wrote.
PHYS | SYSTEMATICS AND BIODIVERSITY