At depths of about 600 to 800 meters (2,000 to 2,600 feet) off the Yucatán Peninsula, giant ‘creamy yellow’ relatives of the wood louse were found.
Scientists have identified a new species bathonymusa famous genus of deep-sea isopods whose viral internet fame has made it the most famous aquatic crustacean since Sebastian’s Sebastian little mermaid.
About 20 kinds of creatures inhabit bathonymus, a mysterious and primitive group that inhabits the bottom layers of the ocean, the deepest depths of which are rarely explored directly. Isopod crustaceans are only distantly related to the better-known decapods: crabs, shrimp, and lobsters.
A group of researchers has revealed the newest creature on this list – B. yukatanensis, a new species about 26 cm (10 in) long. This makes them about 2,500% larger than common woodlice. Scientists from Taiwan, Japan and Australia published their findings in a peer-reviewed journal on August 9. natural history journal.
Deep-sea isopods belong to the same group that includes terrestrial isopods, variously known as boletus, pilumushi, and lowry poly. These feed on rotting matter, and anyone who has ever lifted a rock or dug a garden will know. Indeed, they are very similar, but due to their amazing size, the largest of them grow to almost 50 centimeters (20 inches). And just like wood lice, they may look a little scary, but they’re completely harmless to humans.
this discovery B. yukatanensis Adds another addition to the isopod pantheon, bringing the total known species bathonymus 3 in the Gulf of MexicoB. giganteus Described in 1879, B. Maximorum It was listed in 2016.
Originally thought to be a variant B. giganteus, one of the largest deep-sea isopods. But in 2017, in the Gulf of Mexico off the Yucatán Peninsula, his closer examination of specimens caught in baited traps at depths of 600 to 800 meters (2,000 to 2,600 feet) revealed a range of unique features. rice field.
“B. yukatanensis Morphologically different from both B. giganteus When B. Maximorum,” claims the author.
This individual, held by the Enoshima Aquarium in Japan, was subtly different from its close relatives. “compared to B. giganteus, B. yukatanensis It has leaner proportions, shorter overall length…and a pereopod [thoracic limbs] It’s thinner,” researchers observe. The antenna is also long. The two species have the same number of pleotelson spines. These spines protrude from the end of the crustacean’s tail.
“Vachinomus giganteus Discovered more than a century ago and over 1,000 specimens have been studied, until now there has been no suggestion of a second species with the same number of pleoterson spines. ,simply B. yukatanensis misidentified as B. giganteus”
“compared to B. Maximorumthe most characteristic feature is the number of pleotherson spines. B. yukatanensis vs 7 inch B. Maximorum”
The speckled creamy yellow color of the shell further distinguished it from its gray relatives.
To make sure, the researchers performed molecular genetic analysis, B. giganteus When B. yukatanensis“Due to the different sequences and morphological differences of the two genes (COI and 16S rRNA), we identified it as a new species,” they write.The phylogenetic tree they constructed B. yukatanensis as most closely related to B. giganteus.
“B. giganteus is actually the closest species B. yukatanensis,” claims the author. “This indicates that the two species likely had a common ancestor. batinomus seed. in the tropical western Atlantic.
The paper also notes that South China Sea specimens are B. Kensley actually B. Jamesi. B. Kensley It is confined to the Coral Sea off the coast of Australia.
“The seeds are becoming more and more apparent. batinomus The overall appearance may be very similar, and the genus also has a long history of species misidentification,” the authors warn.
They note the conservation implications of these newly established species distinctions. “Some species of Vatinomus with commercial potential have been targeted by deep-sea trawl fisheries,” they say. Giant isopods are used only sporadically, but “for management” batinomus In fisheries it is important to know exactly which species are being caught. ”
Reference: “New species batinomus Milne-Edwards, 1879 (Isopod: Cirolanidae) from southern Gulf of Mexico Vachinomus jamesi Kou, Chen and Li, 2017 from off Pratas Island, Taiwan” by Ming-Chih Huang, Tadashi Kawai and Niel L. Bruce, 9 August 2022, natural history journal.