In the coastal waters of Okinawa, researchers have discovered two species of cephalopods named in honor of traditional Japanese folklore of nature spirits that inhabit trees. Okinawa is a subtropical island chain in Japan, and its nearby underwater landscape is one of the most diverse ecosystems on Earth. These vibrant and delicate sea gardens contain more than 360 species of coral and support countless animal species.
Now, researchers from the Okinawa Institute of Science and Technology (OIST) and other universities in Japan and Australia have made progress in cataloging this abundant creature by describing two new species of squid, Idiosepiuskijimuna (Ryukyu-himeika1 in Japanese) and Kodamajujutsu (Tsuno-himeika in Japanese).
The scientific names of the two new species come from Japanese folklore related to their appearance and behavior. Idiosepiuskijimuna is named after the red-haired, dwarf forest fairy said to live under the Okinawa banyan tree. True to their name, these tiny, reddish squid spend most of their time in forest habitats, clinging to vegetation in shallow seagrass beds near the coast.
Kodamajujutsu is a newly discovered species and belongs to a completely new genus. The genus Kodama is named after the round-headed wood spirit, which is said to live in ancient trees and whose presence heralds the health of the forest.
The perhaps unusual species name "Jiu Jitsu" alludes to the similarity of the squid's predatory behavior to Japanese martial arts. Jeffrey Jolly from OIST's Marine Climate Change Research Group said: "The core of Jiu-Jitsu is grappling and using the opponent's strength, and Kodama Jiu-Jitsu is about preying on shrimps larger than itself through forearm grappling. The squid has also been observed raising its arms and curling them above its head, reminiscent of a martial arts posture."
Finding this tiny squid is no easy task. Both species of squid deserve their name because they are so small - the largest specimen is just 12 millimeters long, shorter than a sewing needle.
Additionally, both species of squid are active only at night, and the woody squid is only found in the winter. Even so, this species has been caught and (incorrectly) identified on several occasions because they are found in relatively accessible shallow seagrass beds. This is in stark contrast to the more elusive woodling squid, which only occurs in coral reefs where, as Jeffrey Jolly puts it, "there are so many other things to see that finding a tiny squid the size of a fingernail is not easy," even for experienced ocean photographers.
The discovery and documentation of both species was made possible by the collaboration of scientists and underwater photographers. Jeffrey Jolly initially began cataloging the two species at the Molecular Genetics Unit at the Australian Institute of Science and Technology (Molecular Genetics Unit at OIST), and the project spanned researchers from both units as well as multiple Australian universities. In particular, the work of underwater photographers and naturalists Shawn Miller, Keishu Asada and Brandon Ryan Hannan has contributed greatly.
Like their mythical name, these squid are closely associated with their natural environment in Okinawa's emerald waters. Unfortunately, these habitats are threatened by human activities, especially climate change that is causing ocean temperatures to rise, which may cause coral bleaching. Overfishing, land reclamation and soil erosion also threaten the underwater homes of these critters, no matter how big or small they are.
According to Geoffrey-Jolly, this is one of the many reasons why taxonomy remains important: "Taxonomy is not as flashy as other sciences, but through the naming and characterization of species, it both highlights the amazing diversity of life in the ocean and reminds us that there is still much we don't know yet."
Reference: "Amanda Reid, Noriyosi Sato, Jeffrey Jolly, and Jan Strugnell published in Marine Biology on October 21, 2023: "Two new species of squid Idiosepiuskijimunan from the Ryukyu Islands, Japan.sp."
DOI:10.1007/s00227-023-04305-1
Compiled source: ScitechDaily