The firefly genus Pteroptyx Olivier revisited (Coleoptera: Lampyridae: Luciolinae)

Abstract

The synchronous firefly genus Pteroptyx Olivier is reassessed from morphological, molecular, and habitat perspectives in Malaysia, and includes some reliably associated females described from morphological features and internal female reproductive anatomy. Phylogenetic analyses using combined morphological and molecular data (where available) for 158 taxa supported all the major features of the existing taxonomic categories within the Indopacific Luciolinae. They revealed a distinct Pteroptyx clade as a morphologically variable genus with Poluninius selangoriensis Ballantyne being newly synonymised with Luciola testacea Motschulsky, the type species, which is redescribed from the type series. Pteroptyx gelasina Ballantyne was shown to be distinct and three of the four morphological subdivisions within Pteroptyx malaccae (Gorham) considered useful. A new species Pt. balingiana Jusoh sp. nov. is described from Sarawak. A second specimen of Pt. gombakia Ballantyne is described and figured. Some females were reliably associated with identified males by molecular data, but investigation of their morphology showed consistent features that were for the most part not useful for species delineation, which still relies on association with the males and colour patterns. All females investigated had bursa plates.Habitat details for most Pteroptyx revealed an association with a riparian environment likely to support mangroves but not necessarily an obligatory association with mangroves or any particular species. Pteroptyx galbina Jusoh was found up to 30 km from the sea, and Pt. bearni Olivier displays in a variety of flowering plants alongside rivers, including mangroves.Keys to species and diagnoses of all species with coloured plates are given.

Phylogeography and Molecular Species Delimitation Reveal Cryptic and Incipient Speciation in Synchronous Flashing Fireflies (Coleoptera: Lampyridae) of Southeast Asia

“…Fireflies are best known for the ability of males to emit precise flashing patterns to attract females, although not all species are luminescent (Lloyd, 2002). The most spectacular of all flashing displays is the near-to-perfect synchronous flashing of fireflies from the genus Pteroptyx Olivier (subfamily Luciolinae), where species are known to occur in multitudes on trees and shrubs along tidal rivers of mangrove swamps (Jusoh, Ballantyne, Lambkin, Hashim, & Wahlberg, 2018). Its highly precise synchronous flashing and tree-swarming behaviour have attracted scientific as well public interests to explicate the mechanisms for their synchronicity (Buck, 2004), elucidate congregating and courting behaviour (Case, 2007; Lloyd, Wing, & Hongtrakul, 2006) and recently, develop as icon species for sustainable ecotourism and conservation (Khoo et al 2012).…”

“…According to recent studies (Ballantyne et al, 2015; Jusoh et al, 2018), Pteroptyx is an Oriental genus comprising 18 species distributed from Hong Kong, southwards throughout Southeast Asia including India (Madras) (Ballantyne, Fu, Shih, Cheng, & Yiu, 2011; Ballantyne & McLean, 1970) and the Philippines (Ballantyne, 2001). Most species in this genus are known to occupy mangroves, riparian, or coastal habitats (Ballantyne et al, 2011; Jusoh et al, 2018; Jusoh, Hashim, & Ibrahim, 2010).…”

“…According to recent studies (Ballantyne et al, 2015; Jusoh et al, 2018), Pteroptyx is an Oriental genus comprising 18 species distributed from Hong Kong, southwards throughout Southeast Asia including India (Madras) (Ballantyne, Fu, Shih, Cheng, & Yiu, 2011; Ballantyne & McLean, 1970) and the Philippines (Ballantyne, 2001). Most species in this genus are known to occupy mangroves, riparian, or coastal habitats (Ballantyne et al, 2011; Jusoh et al, 2018; Jusoh, Hashim, & Ibrahim, 2010). For instance, at least eight out of 12 species of Pteroptyx were recorded from mangroves throughout Malaysia (Jusoh et al, 2018), followed by four species in Thailand (Sartsanga, Swatdipong, & Sriboonlert, 2018), two to three species in Singapore (Chan, Ballantyne, & Goh, 2012), and one species in the Phillippines (Ballantyne et al, 2011; Jusoh et al, 2018).…”

“…Most species in this genus are known to occupy mangroves, riparian, or coastal habitats (Ballantyne et al, 2011; Jusoh et al, 2018; Jusoh, Hashim, & Ibrahim, 2010). For instance, at least eight out of 12 species of Pteroptyx were recorded from mangroves throughout Malaysia (Jusoh et al, 2018), followed by four species in Thailand (Sartsanga, Swatdipong, & Sriboonlert, 2018), two to three species in Singapore (Chan, Ballantyne, & Goh, 2012), and one species in the Phillippines (Ballantyne et al, 2011; Jusoh et al, 2018). For centuries, species descriptions in the subfamily Luciolinae, which includes Pteroptyx , have been based purely on morphology.…”

“…However, without morphological characters of the male genitalia and highly trained taxonomists, fireflies are difficult to identify to the species level (Ballantyne, 2012). Moreover, it is almost impossible to provide accurate identification of female and larval specimens, even to the genus level unless the specimens were collected in association with the male (Jusoh et al, 2018). Thus, additional methods and data streams are needed to facilitate species discovery in order to realize the true extent of firefly diversity in the region.…”