Guwahati: A stingless bee barely 5 mm long has been found living nearly 80 cm beneath the soil in Nagaland, with researchers discovering an underground colony connected to the surface by a 1.1-metre-long tunnel and containing an estimated 350–400 ml of honey.
The bee has been identified as a new species and named Tetragonula nagalandensis, after the state where it was discovered. The species was found at Medziphema and formally described in a study published online in the journal Oriental Insects.
What makes the discovery particularly unusual is the bee’s underground lifestyle. Researchers found colonies at a depth of 76.2 to 79.2 cm in moist soil rich in humus and decayed organic matter.
A round entrance, about 1.2 cm wide, led into a 110-cm-long tube before reaching the nest cavity.
Four to six worker bees were found guarding the entrance and withdrew when the nest was disturbed. Inside, the colony had a nest cavity measuring 14 by 17 cm, with brood, pollen and honey stores.
The honey was kept in dark-grey pots attached around the brood area, while the brood cells were packed into compact clusters.
The researchers estimated that the colony held 350–400 ml of honey. They also noted that the bees were less aggressive compared with other species they encountered.
The male of the new species measures 5 mm in body length, while females average about 4.19 mm.
Although the bee resembles another underground species, Tetragonula kyrdemkulaiensis, the researchers found clear differences in body measurements, abdominal structures and male genitalia.
The discovery was not the result of a single recent field trip. Specimens from Medziphema included females collected in 2017 and 2018, along with additional material collected in 2024.
The researchers subsequently examined the specimens in detail and established the species as new.
The study also fills another gap in the scientific record of Northeast India’s stingless bees. Researchers have described, for the first time, the male of Tetragonula srikantanathi, a species first described in 2021 and previously known only from females. Male specimens were collected in Khowai, Tripura, near its type locality.
Unlike most Tetragonula species reported from India, T. srikantanathi builds its brood in single-cell-thick combs suspended horizontally or obliquely. The species has been recorded in Assam, Nagaland, Manipur, Mizoram, Meghalaya and Tripura.
The findings also highlight how little is known about India’s stingless bees. The researchers noted that females of different species can look remarkably similar, making identification difficult, while male bees and their genital structures can provide important clues for distinguishing species.
Stingless bees are important pollinators of crops and other plants and are also valued for their honey. The researchers said the diversity of stingless bees in India remains incompletely known and that further species are likely to be discovered.
The study was authored by Shashidhar Viraktamath, Avinash Chauhan, Rojeet Thangjam and Malar Bui, with researchers from the University of Agricultural Sciences, Nagaland University and Central Agricultural University( Imphal).
Also Read: Two disasters, one Himalayan warning: Sikkim’s GLOF lessons for Nepal
You just read a story that took days to report. Help us keep our reporters on the ground in the Northeast.
Ad-free reading, support and keep important stories alive
Support once (any amount)
Scan to pay via UPI