A recent study by an entomology researcher identified 37 rare moth species in Kerala. As many as three of them were the rarest and reported for the first time in the country.
Swafvan K., formerly with the Zoological Survey of India (ZSI), Kozhikode, recorded the rare moth species during a two-year-long survey from 2018. P.M. Sureshan, Scientist Emeritus from ZSI, Kozhikode, supervised the study.
The findings were published by the International Journal of Entomological Research. Dr. Swafvan said that the 37 new moth species he identified belonged to 13 families. According to him, there has been a decline in the diversity of moths in the agro-ecosystems of Kerala largely due to excessive use of pesticides, radiation and air pollution.
The three new species reported for the first time in India were Aeolarcha eaphthalma, Pharambara micacealis, and Tirathaba leucotephars. They were found in the coffee plantations of Wayanad.
“When Ashinaga eophthalma was previously reported from China and Hong Kong, the species Pharambara micacealis was reported from Sri Lanka, New Guinea and Australia,” said Dr. Swafvan. The genus Pharambara has about 25 species mostly reported from equatorial Africa and several are unnamed.
Dr. Swafvan monitored the moths in the agricultural plantations of Kasaragod, Kannur, Wayanad, Kozhikode and Malappuram districts on 152 nights from 6 p.m. to 6 a.m. between 2018 and 2020. The survey used light traps, and was held in four different zones in each district.
He said scientific documentation of the moth fauna from northern Kerala was lacking as there were not many lepidopterology studies. As many as 844 moth species belonging to 34 families were reported from Kerala by Balakrishnan Valappil in 2019.
Moths are nocturnal and potential indicators of ecosystem health and changes. With different types of antennae, body scales, coloration, movement and sense of smell, moths are quite different from butterflies.
When butterflies are pollinators, moths are largely considered crop pests. Some reptiles, bats and birds feed on moths and their larvae. “Some moths pollinate the flowers that bloom at night,” said Dr. Swafvan.
Even while posing a threat to crops, moths perform some essential ecosystem services, including pollination, nutrient cycling and providing prey for birds and bats. Therefore, in agro ecosystems, moth abundance is positively related to abundance of crops.
