Jose Rizal’s jewel weevil
Researchers reveal new distribution record of flightless weevil named after National hero Dr. Jose Rizal
APAPER marking a new distribution record of the flightless weevil species, Pachyrhynchus rizali, named after National Hero Dr. Jose P. Rizal, was published by the Philippine Journal of Science and Researchgate last month.
Authored by Jhonnel P. Villegas of the Davao Oriental State University, and Perry Archival C. Buenavente and Analyn A. Cabras both from the National Museum of Natural History, the paper describes in detail the female specimen collected at the Aurora Memorial National Park in Aurora province.
Female specimen
THIS was the first time that a female specimen of the species named after Rizal was described since the discovery of the species in 1934.
Cabras told the Businessmirror via Messenger on March 17 that the paper presents the first female description.
“When it was described by [entomologist] Wilhelm Schultze back in 1934 he only did the male,”cabras explained, adding that it was a common practice back then.
The specimen was collected on June 18, 2023, a day before Rizal’s 162nd birth anniversaryl.
The specimen was identified based on morphological (form and structure) comparison with the types deposited at the Senckenberg Natural History Museum in Dresden, Germany.
Flightless weevil
PACHYRHYNCHUS GERMAR, 1824 (Coleoptera: Curculionidae) is a genus of weevils known for their flightless ability, unique and iridescent elytral (tough fore wings) colorations and patterns.
The authors said its center of diversity is in the Philippines, which has the greatest number of species, with Luzon Island hosting the majority of known Pachyrhynchus species.
“In recent years, there has been a surge of interest in conducting various coleopterological [scientific study of beetles] expeditions, especially in underexplored islands like Mindanao, wherein several species have been described,” the paper said.
Rizal, a naturalist
ACCORDING to the authors, Rizal was a naturalist with a myriad of documented correspondence with Dr. Adolph Bernhard Meyer, director of the Königlich Zoologisches und Anthropologisch-ethnographisches Museum, now the Museum für Tierkunde Dresden, in Dresden, Germany.
“Rizal sent several natural collections to Germany, advancing global knowledge of Philippine biodiversity,” the authors said, citing another paper by naturalist Emanuela Carli in 2006.
Several species have been named after Rizal: Draco rizali Wandolleck, 1900; Rachophorus rizali Boettger, 1897; Spathomeles rizali Strohecker, 1964; and Apogonia rizali Heller, 1897.
Natural history collection
RIZAL had his collection and can be considered a contributor to the country’s natural history collection.
“Rizal corresponded with Meyer, the curator of Dresden museum, and sent him lots of specimens from the Philippines that include birds, frogs and beetles, in exchange for books and scientific stuff,” Cabras said.
“Unfortunately Dresden was bombed during WWII [World War 2] and we lost also a good number of specimens sent by Rizal. Fortunately, the insects were saved and transferred on time so they remain intact,” she said.
Cabras said Rizal was one of the early naturalists in the Philippines but was less credited for it.
“His travels to Europe and talking to curators made him realize the importance of keeping a natural history collection,” Cabras said.
Endemic species
P. RIZALI is endemic to the Philippines, which means it is not found anywhere else in the world.
“Its distribution is probably highly restricted to the Sierra Madre mountain range. This means that once this habitat is gone, the entire species can be easily decimated,” Villegas said.
“I think what’s more interesting about P. rizali is its unique relationship with Philippine history and the Filipino identity. It demonstrates that Jose Rizal was a wellrespected figure among the international naturalists at the time. He is also one of the earliest Filipinos who recognized the true importance of natural history collections in the country, something that is not wellregarded at present,” Villegas explained.
Survivor species
CAPTURED through opportunistic sampling at the back of a house with a small commercial store along the roadside, the P. rizali was observed crawling in a decaying fallen tree log coiled with creeping vines.
“It can be inferred that the species could tolerate minimal anthropogenic [human-caused] disturbance similar to other Pachyrhynchus species as long as there is a remnant of the original habitat left,” the authors said.
This is a similar observation with amphibians and reptiles, whose population remains to cling on as long as there are residual habitats left.
Wide distribution
VILLEGAS said the discovery of the P. rizali within the Aurora Memorial National Park signified a wider distribution of the species in the fragmented Northern Sierra Madre biotic region.
“The recent discovery highlights the importance of protecting forest ecosystems as a sanctuary of underappreciated weevils. It also mainstreams and popularizes a relatively unknown species named after the Philippine National Hero, Dr. Jose P. Rizal,” he told the Businessmirror via Messenger on March 16.
Villegas believes the flightless weevil was already in the area before and was just separated from other populations with the forest fragmentation and land-use changes in Aurora.
Little-known insect
P. RIZALI is a little-known weevil. Villegas said that at present, only studies about the taxonomy and records on the distribution of P. rizali are known to science.
“There is so much to be learned about the species. For example, the development biology of P. rizali [from the egg stage to adulthood] is still undocumented. We can also study what environmental conditions and food habits favor the survival of the species, something that is useful for its conservation,” he pointed out.
Cabras added that other than being an endemic species to Luzon, P. rizali is a posthumous honor 38 years after Rizal’s death.
“P. rizali is still a valid name. All the beetles named after Rizal along with Apogonia rizali and Spathomeles rizali are all valid names still being used today,” Cabras added.
Protect the habitat, protect the weevil
ACCORDING to Villegas, the recent discovery of the new population distribution in Aurora highlights the need for a proactive approach to biodiversity conservation.
“We need to be more proactive in our biodiversity conservation efforts. Aside from protecting and managing forested landscapes, there is a more pressing need to regenerate damaged ecosystems. In this way, we are restoring the natural habitats of our small but ecologically important beetles,” he said.
For her part, Cabras said people should bear in mind the importance of even the smallest creature on the planet—the insects.
“If you find some insects or spiders or any wildlife, be kind and do not kill them. As for Pachyrhynchus rizali, I hope the LGU [local government unit] in Aurora will create a policy to protect this special weevil from getting extinct,” she said.
According to Cabras, keeping its habitat intact is important but so is educating the locals not to collect them and similar species, especially since there’s an ongoing illegal trade in Aurora.
Threat to beetles’ population
CABRAS said that besides habitat destruction, the illegal trade of beetles is a growing concern, particularly in Aurora province.
Villegas agreed, adding that during their research, there were locals who said they were asked by collectors to collect beetles.
The collectors require the preservation of the beetles by putting them in a container of alcohol.
The selling price depends on the species. But some are not even bought by the collector, so there’s a tendency for the beetles to be killed for nothing.
According to Cabras, based on an initial investigation they conducted, most Pachyrhynchus (a genus of weevils) range from P1,000 to P5,000 depending on the rarity of the species, and the color variation, or if the species is new.
“If it’s a new species, they are way more expensive,” Cabras said, adding that the collectors may be researchers who come up with a report without doing the legwork.
“Collectors and amateur researchers are alike,” she quipped.
“These weevils are highly coveted abroad. They are being considered as one of the most beautiful weevils in the world,” she said.
She said they are bought cheaply in the communities, but when selling them online, the price is much higher in the international market.
She disclosed one platform that is notoriously allowing the trade of beetles.
“This is heartbreaking, especially since these species have narrow geographic ranges and are found only in a particular mountain, mountain range, or island,” she said, meaning that collecting them with the huge prize money in mind may lead to the species’ eventual extinction.