UPLB scientist discovers insect behind lanzones infestation

LOS BAÑOS, Laguna—A new species of armored scale insects infesting lanzones farms in several areas in the Philippines has been discovered by a scientist from the University of the Philippines Los Baños (UPLB).

The pest, called Unaspis mabilis Lit & Barbecho, n.sp., was likened to the coconut scale insects (Aspidiotus rigidus), locally referred to as cocolisap, as both belong to the Diaspididae family.

“They both have scales [covering their bodies] made of wax and their females are wingless,” UPLB scientist Dr. Ireneo Lit Jr. said in a phone interview on Sunday. Lit and his apprentice, Normandy Barbecho, published their findings on the scaled insect in a German scientific journal, Arthopoda Generalis, on Nov. 25.

The round-shaped cocolisap, first detected in Batangas province in 2009, causes the leaves of coconut trees to dry up and wither. It has affected more than 2.1 million coconut trees in an outbreak in Calabarzon (Cavite, Laguna, Batangas, Rizal and Quezon) alone, according to government reports.

Lit said the mussel-shaped Unaspis mabilis specifically targets lanzones by “sucking out the plant sap from the leaf tissues.”

“It spreads fast,” said Lit, who is also director of the UPLB Museum of Natural History. Hence, farmers call it “mabilis” (fast), he added.

The scientist has been studying the insect since its presence was first detected in Makilala town, North Cotabato province, in 2009. He said that in five years, the infestation had already spread to parts of Aklan, Mindoro and Laguna provinces.

“We even have it here already on Mt. Makiling,” Lit said.

Earlier studies had referred to the insect as the Lanzones “mussel scale” and identified it as belonging to the Lepidosaphes sp. or Lepidosaphes beckii species.

But Lit and Barbecho, who is pursuing graduate studies in entomology, concluded in May that it was a new species they found in the Philippines.

“We suspect that it was introduced to the Philippines through the exportation of larger varieties of lanzones from Thailand or Malaysia,” Lit said.

The insect was described as having “aggressive behavior,” a characteristic of an invasive alien species.

Its scale armor serves as protection against ordinary pesticides, Lit said. “Trunk-injection [of pesticides] has been tried before but the lanzones plants only died,” he said.

Lit and his assistant plan to conduct further studies to find a potential “biocontrol agent” to contain the lanzones infestation.

In July, the Bureau of Plant Industry in Calabarzon ordered to quarantine infested produce and seedlings, including coconuts, mangosteen and lanzones.

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