Rediscovery of the endemic firefly, Harmatelia bilinia Walker (Coleoptera: Lampyridae: Ototretinae) from Ranmale Forest Reserve, Sri Lanka

Abstract

The firefly genus Harmatelia is endemic to Sri Lanka, and H. bilinia was originally described by Walker (1858) based on a specimen collected from ‘Udawaththa’ Forest Reserve, low-wet zone of Sri Lanka. After the original description, there has been no confirmed record of this species in type locality, hence the status of this species in Sri Lanka remained uncertain. However, a male specimen of H. bilinia was rediscovered from ‘Ranmale’ Forest Reserve (6°14'36.7"N, 80°39'09.1"E, 184m above sea level, Walasmulla) in the Southern-Intermediate Zone of Sri Lanka, almost after 164 years of its first record. A living specimen was observed during a recent visual encounter survey of fireflies (2022). It was captured using an insect hand net for close examination and photographs (Nikon Digital Camera D90/60mm-12mpxl), and released back to the same location. Obtained photographs were compared with the pictures of syntype male H. bilinia (NHMUK014006260) in Natural History Museum, London. The external morphology of the observed specimen appeared identical to the original description of H. bilinia. The morphology of the recorded male H. bilinia is presented herein. H. bilinia, male: 8 mm long; antennae flabellate and dark reddish brown, black mesoscutellum and pronotum, lateral and fore edges of pronotum yellowish gold, elytra subparallel, black with a yellowish gold oblique vitta in each elytron; apex of elytra deflexed, legs yellowish brown, six visible abdominal ventrites yellowish brown, eight marginal luminous spots in both sides of ventrites IIVI. It is vital to note the rediscovery of endemic H. bilinia from the Southern intermediate forest after their first record from the wet zone forest in Sri Lanka. Therefore, future studies are recommended on the distribution of H. bilinia in different floristic zones of Sri Lanka.