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Genomic study uncovers a new lace bug species on Japan’s remote Ogasawara Islands

Analysing 52 specimens with a genetic method known as MIG-seq, the team found that an insect previously regarded as a single species, Omoplax desecta, in fact comprised two.

Researchers have used genome-wide DNA data to identify a new insect species on the Ogasawara Islands, a remote Japanese archipelago roughly 900 to 1,000 kilometres south of Tokyo. The findings suggest that evolution among island insects is more intricate than appearances imply. The study is published in the open-access journal ZooKeys.

The Ogasawara Islands are a UNESCO World Natural Heritage site, celebrated for their endemic land snails and plants. Their insects, of which some 440 endemic species are known, have received far less evolutionary attention.

Jun Souma, of Hirosaki University’s Shirakami Research Center for Environmental Sciences, and Naoyuki Nakahama, of the Graduate School of Agriculture at Osaka Metropolitan University, examined Omoplax, a genus of lace bugs found nowhere else and thought to have diversified rapidly across the islands.

Analysing 52 specimens with a genetic method known as MIG-seq, the team found that an insect previously regarded as a single species, Omoplax desecta, in fact comprised two. Populations on the Chichijima and Hahajima island groups were genetically distinct, and subtle differences in male genitalia confirmed the split. The Hahajima population is now described as Omoplax sandoru, named after the local name of its host plant.

*Omoplax desecta* (nymph). Image credit: Jun Souma.

*Omoplax desecta* (adult). Image credit: Jun Souma.

Souma was first drawn to Omoplax desecta by its unusual diet:

“The reason I took a particular interest in Omoplax desecta is that it feeds on both the native plant Rhaphiolepis indica var. tashiroi and the introduced plant Calophyllum inophyllum in the Chichijima island group.

This is quite unusual for lace bugs, which typically exhibit high host specificity. I was also intrigued by the fact that it is distributed across multiple island groups, which is different from other Omoplax species.”

The Hahajima population posed its own puzzle:

“I had wondered why it fed exclusively on Rhaphiolepis indica var. tashiroi and why there were no individuals with dark brown to black pronotum, which are sometimes seen in the Chichijima island group.

After conducting population genetic and phylogenetic analyses, I began to suspect that this population might be a distinct species. Upon closely observing their morphological characteristics, I was certain of this.”

Jun Souma, conducting observation on *Calophyllum inophyllum* where *Omoplax desecta* feeds. Image credit: Jun Souma.

The evolutionary tree also overturned expectations:

“The most surprising finding of my research was that species feeding on the same plant and appearing very similar are not necessarily sister groups.

Adaptive radiation among insects on oceanic islands may be more complex than comparisons of morphological characteristics and life histories would suggest at first glance.”

The results point to both geographic isolation and shifts between host plants as drivers of speciation.

*Rhaphiolepis indica* var. *tashiroi*. Image credit: Jun Souma.

Of particular interest is the insect’s adoption of Calophyllum inophyllum, a tree introduced by people. The data indicate that this host shift occurred once, and recently.

“I also find it interesting that the introduction of Calophyllum inophyllum by humans may have led to a budding of future speciation in Omoplax desecta.”
Jun Souma

*Calophyllum inophyllum*. Image credit: Jun Souma.

The authors note that DNA could not be obtained from two rare species, leaving parts of the story unresolved. Further sampling will be needed to trace how these insects reached the islands and diversified.

Original source:

Souma J, Nakahama N (2026) Genome-wide SNP data reveal phylogenetic relationships and further new species of lace bugs (Hemiptera, Heteroptera, Tingidae) endemic to the Japanese oceanic islands (the Ogasawara Islands), providing insight into their speciation. ZooKeys 1294: 175-203. https://doi.org/10.3897/zookeys.1294.205145

For more articles on zoology, visit the ZooKeys website and follow the journal on BlueSky and Facebook.

Conservation hopes up for the endangered banana frog restricted to Southwest Ethiopia

As the natural forest cover in Ethiopia is already less than 3% of what it once has been, the banana frog species, dwelling exclusively in the remnants of the country’s southwestern forests in only two populations, is exposed to a great risk of extinction.

Through their survey, a research team, led by Matthias De Beenhouwer, Biodiversity Inventory for Nature Conservation (BINCO), Belgium, have now extended the species’ range, thus making the first steps to saving the charming frogs. The study is published in the open-access journal ZooKeys.

Although Ethiopia is known for its high number of both animal and plant species that do not live anywhere else in the world, there is a concerning lack of conservation activities to preserve the local biodiversity. Moreover, while as much as 41% of the amphibians ever recorded in the country are exclusive for its fauna, there have been only few researches. Without such, pointing the hotspots in greatest need of protection and restoration, as well as taking adequate measures subsequently, is impossible.

Concerned about the endangered status of the banana frog, and supported with a Rufford grant, Matthias and his team spent ten evenings, or 111 hours, in August 2014, seeking and collecting as many frogs as possible from seven different locations. When they determined the species status of the found individuals, it turned out that they have managed to discover several new populations of banana frogs from unexpected localities.

As a result of their survey, the geographical range of the Ethiopian banana frog has been expanded by roughly 40 km towards the North and 70 km to the East. Its altitudinal distribution already reaches a maximum of 2030 metres above sea level, compared to the previously known maximum of 1800 m.

Banana frogs being identified from outside forest habitats is also a good news for the species’ preservation since it shows that not only are the frogs more tolerable against forest degradation than expected, but that also there could be even more populations.

“Although Southwest Ethiopia is known to harbour the last large tracts of natural forest, forest cover has declined dramatically to less than 3% nationwide,” point out the researchers. “Therefore, accurate information on species conservation and distribution is an essential first step to facilitate the delivery of conservation updates, recognize biodiversity hotspots and encourage habitat protection and restoration.”

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Original source:

Mertens J, Jocqué M, Geeraert L, De Beenhouwer M (2016) Newly discovered populations of the Ethiopian endemic and endangered Afrixalus clarkei Largen, implications for conservation.ZooKeys 565: 141-146.doi: 10.3897/zookeys.565.7114

Under the wing of science: Two methods for aging nestling Carnaby’s cockatoo species

Multi-year research on two populations of the endangered endemic Carnaby’s cockatoo in southwestern Australia was conducted in order for two separate methods for nestlings aging to be assessed. If accurate enough, Dr. Denis Saunders and his team believe that the results could be vital in the threatened species’ preservation, as explained in the Carnaby’s cockatoo’s recovery plan.

One of the methods they have looked into is based on changes in the physical appearance of nestlings over the 10-11 week nestling period. The other relies on measurements of a nestling’s folded wing length and its comparison with growth curves from measurements of nestlings of known age. In their paper the Australian team also examines the timing and length of the egg-laying season. Their research is published in the open-access journal Nature Conservation.

The researchers point out that accurate nestling aging is essential for many ecological studies. The data could be used in investigating population dynamics, life histories, behaviour, longevity, conservation planning and management. It could also help in scheduling the visits of breeding areas so that the disturbance for the populations is minimised without compromising the results.

The scientists found out that observing the changes in a nestling’s size and feathers is less accurate than measuring the folded wing length. Its main disadvantage turned out to be the lack of distinguishable physical changes once the birds become about nine-week-old. However, “with experience it may be useful for gaining an approximation of the commencement and end of the breeding season without having to handle nestlings to take measurements,” the team says.

Their research on the egg-laying dates concluded that the most effective approach for examining nestlings is to conduct two visits per breeding season. Curiously, their findings showed that in wetter autumns the egg-laying begins earlier.

The team also suggests that their methods could be adopted for aging the currently under-researched closely related Baudin’s cockatoo until more species-specific technique is found.

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Original source:

Saunders DA, Dawson R, Nicholls AO (2015) Aging nestling Carnaby’s cockatoo, Calyptorhynchus latirostris, and estimating the timing and length of the breeding season.Nature Conservation 12: 27-42. doi: 10.3897/natureconservation.12.4863