A new deep-sea isopod from Bathonymus

Large new deep-sea isopod discovered in Gulf of Mexico — 2,500% bigger than common psyllid

Image of Bathynomus yucatanensis. Image credit: Dr. Ming-Chih Huang, Natural History Journal

Near the Yucatan Peninsula, a giant “cream-yellow” relative of Woodlouse was found living at depths of 600 to 800 m (2,000 to 2,600 ft).

Scientists have discovered a new species MusaThe famous genus of deep-sea isopods whose viral internet fame has made them the most famous aquatic crustaceans since Sebastian Little Mermaid.

about 20 creatures Musa, a mysterious and primitive group that inhabits the deepest parts of the ocean—its deepest depths that few have personally explored. Isopod crustaceans are only distantly related to their better-known decapod relatives, crabs, shrimps and lobsters.

A team of researchers has just revealed the newest creature to this list — B. yucatanensis, a new species about 26 cm (10 in) long. This makes it 2,500% larger than a regular ground lice.Scientists from Taiwan, Japan and Australia published their findings in peer-review on August 9 journal of natural history.

Deep-sea isopods belong to the same group that includes terrestrial isopods known as psyllids, drug bugs, and roly polys. They feed on decaying matter and are likely familiar to anyone who lifts rocks or digs soil in a garden. In fact, they look very similar, but they are quite large – the largest of them grows to nearly 50 cm (20 inches). And, like psyllids, while they may look a little intimidating, they are completely harmless to humans.

Their bizarre features and unusual size have spawned endless memes and products celebrating their lovable weirdness, from stuffed animals to phone cases.

this discovery B. yucatanensis Added another member to the isopod pantheon and brought the total number of known species Musa In the Gulf of Mexico to three—B. giganteus described in 1879 B. maxeyorum Described in 2016.

it was originally thought to be B. giganteus, one of the largest deep-sea isopods. However, closer inspection of the specimen, which was caught by bait in 2017 at about 600 to 800 meters (2,000 to 2,600 feet) in the Gulf of Mexico near the Yucatan Peninsula, revealed a range of unique features.

B. yucatanensis morphologically different from both B. giganteus and B. maxeyorum,” the authors claim.

Held by the Enoshima Aquarium in Japan, the individuals studied differed slightly from their relatives. “compared to B. giganteus, B. yucatanensis Body proportions are slimmer and overall length is shorter… [thoracic limbs] more slender,” the researchers observed. It also has longer antennae. Both species have the same number of pleotelson spines. These spines protrude from the crustacean’s tail.

giant bass More than 1,000 specimens were found more than a century ago, and until now there has been no indication that a second species has the same number of pleotelsonic spines,” they add. “Superficial examination using only pleotelsonic spines could easily lead to B. yucatanensis mistaken for B. giganteus. “

“compared to B. maxeyorumThe most notable feature is the number of pleotelson spines – 11 spines B. yucatanensis compared to 7 inches B. maxeyorum. “
The speckled, creamy yellow color of the shell further distinguishes it from its gray relatives.

To be sure, the researchers performed molecular genetic analysis, comparing B. giganteus and B. yucatanensis“Due to the sequence differences of the two genes (COI and 16S rRNA), coupled with morphological differences, we identified it as a new species,” they wrote.The phylogenetic tree they constructed showed that B. yucatanensis as the most closely related B. giganteus.

B. giganteus indeed the closest species B. yucatanensis,” the authors assert. “This suggests that the two species may have shared a common ancestor.In addition, there may be other undiscovered Batinomus spp. in the tropical western Atlantic.

The paper also clarified that the specimen from the South China Sea was identified as B. kensleyi in reality B. jamesi. B. kensleyi Limited to the Coral Sea off the coast of Australia.

“It is becoming increasingly apparent that Batinomus are likely to be very similar in overall appearance, and there is a long history of misidentification of species within the genus,” the authors caution.

They point out that these newly established species distinctions have conservation implications. “A number of Bathynomus species with commercial potential have been targeted by deep-sea trawling fisheries,” they said.Although giant isopods are exploited only occasionally, “for management Batinomus In fisheries, it is important to know exactly which species are caught. “

Reference: “A New Species Batinomus Milne-Edwards, 1879 (Isopoda: Cirolanidae) from the southern Gulf of Mexico, re-described potato Kou, Chen, and Li, 2017 from Platas Island, Taiwan” by Ming-Chih Huang, Tadashi Kawai, and Niel L. Bruce, August 9, 2022, journal of natural history.
DOI: 10.1080/00222933.2022.2086835

Leave a Comment

Your email address will not be published.