Environmental Science and Informatics Section (OIST) team member Jake Lewis is dealing with the taxonomy and advancement of weevils. Presently, he is using a broad variety of strategies like microscopy, dissections, DNA analysis, and X-ray microtomography to find and describe brand-new types across Asia. Credit:
” When I got here at OIST in 2022, I dove headfirst into the OIST weevil collection. As I carefully examined them, this types immediately captured my eye. It clearly came from the genus Acicnemis, but differed from anything else described from East Asia,” recounts Lewis. “Its extended scales and special coloration set this types apart from other known Japanese species.”
The genus Acicnemis consists of over 180 species, so confirming the discovery of a new types within this genus requires a thorough evaluation of the existing literature and museum collections. As the “type specimens” (the original specimens used for types description) in the genus Acicnemis are housed in European and Japanese museums, Lewis had to reach out to numerous organizations, including the Kyushu University Museum (Japan), the Natural History Museum in London (UK), and the Senckenberg German Entomological Institute (Germany) in order to validate the status of Acicnemis ryukyuana as an unique types.
3D models produced using X-ray microtomography show the distinctions in leg shape in between the newly discovered Acicnemis ryukyuana and Acicnemis postica. The shape of the 2nd segment of the leg is evenly curved in Acicnemis postica (A and B), however wavy along the inner edge in the brand-new species Acicnemis ryukyuana (C and D). Credit: OIST
Weevils form one of the most varied animal groups on the planet and typically feed on plants. Some weevil species are highly specialized and have a narrow range of plants they can feed upon. The host plant( s) for this brand-new types remain unknown, and Lewis wants to perform additional field research studies examining this.
The distinguishing characteristics of Acicnemis ryukyuana
Acicnemis ryukyuana can be instantly acknowledged by the yellow bands on its shoulders, and unique pattern of grey, black, and yellow scales on its hard forewings. Other distinct functions noticeable under the microscope include the long scales (hairs) on the back and the shape of the last section of the leg.
The newly found Acicnemis ryukyuana (A) and other Acicnemis types discovered in Okinawa. A) Acicnemis ryukyuana, B) Acicnemis postica, C) Acicnemis azumai, D) Acicnemis exilis, E) Acicnemis maculaalba, and F) Acicnemis kiotoensis. Credit: OIST
” Based on the special set of functions observed in this brand-new species, A. ryukyuana seems carefully associated to some other species in southeast Asia, nevertheless, DNA analyses will be required to verify this,” discusses Lewis.
” I was drawn to Okinawa as there are various undescribed weevil types in the region, unlike in Canada, my home country, where weevils have been much more completely studied. “The Ryukyu Islands provide an irresistible play area for taxonomists, abundant in types which you only find here”.
The beetles sensitivity to human presence
OIST scientists dispersed insect traps commonly across Okinawa Island consisting of greatly inhabited and disturbed areas, A. ryukyuana was just recorded in a pristine, specifically safeguarded part of Yanbaru National Park. The brand-new species was also gathered in well-preserved subtropical forest locations on Ishigaki Island; and located by Lewis in the Kyushu University Museum collection. “Based on these collection locations, this weevil species appears to be extremely delicate to human disturbance compared to other Acicnemis types commonly discovered in the Ryukyu Islands.”
” This recently found beetle may be considered a vulnerable, endemic aspect of the Ryukyu animals, comparable to the flight-less bird Okinawa rail, the Yanbaru long-armed scarab beetle, and the Okinawa spiny rat,” says Lewis. “I make sure that taxonomists, preservation biologists, and regional biologists in Okinawa will be interested in knowing that yet another amazing species has been found in the Ryukyu Islands.”
Reference: “A New Species of Acicnemis Fairmaire, 1849 (Coleoptera: Curculionidae) from Okinawa and Ishigaki Islands, Okinawa Prefecture, Japan” by Jake H. Lewis, 16 June 2023, The Coleopterists Bulletin.DOI: 10.1649/ 0010-065X-77.2.185.
In most Acicnemis types the same leg section is heart-shaped and heavily indented (revealed here in Acicnemis postica, B). “Its extended scales and distinct pigmentation set this species apart from other known Japanese types.”
The shape of the second section of the leg is equally curved in Acicnemis postica (A and B), however wavy along the inner edge in the brand-new types Acicnemis ryukyuana (C and D). The freshly discovered Acicnemis ryukyuana (A) and other Acicnemis species found in Okinawa.” I was drawn to Okinawa as there are various undescribed weevil species in the area, unlike in Canada, my home nation, where weevils have actually been much more thoroughly studied.
By Okinawa Institute of Science and Technology (OIST) Graduate University
September 6, 2023
Acicnemis ryukyuanas unique colors and leg shape: Acicnemis ryukyuana (A) can be differentiated by the yellow bands on its shoulders and the color of its solidified fore wings. In many Acicnemis species the exact same leg sector is greatly indented and heart-shaped (shown here in Acicnemis postica, B).
The weevil has distinct characteristics and is sensitive to human disruption.
A brand-new weevil species has actually been discovered in the beautiful subtropical forests of Ishigaki Island and Yanbaru National Park in Okinawa, Japan.
The Ryukyu Islands, a chain of subtropical islands extending between mainland Japan and Taiwan, are celebrated for their outstanding biodiversity. With an unique evolutionary past due to their relative seclusion, these islands house a selection of appealing insect species.
Researchers at the Okinawan Institute of Science and Technology (OIST) have actually been placing net traps to keep track of pests on Okinawa Island given that 2015, and have caught a wide variety of bugs, consisting of beetles, bees, flies, and wasps, which are protected in ethanol, stored and dried in the OIST insect collection. The freshly discovered beetle types, Acicnemis ryukyuana, was successfully identified through microscope analysis and dissection by OIST entomologist Jake H. Lewis, who works as Collection Manager in the OIST Environmental Science and Informatics Section.