A New Genus and Two New Species of Fireflies from South America (Lampyridae: Lampyrinae: Photinini)

Abstract

Lampyridae taxonomy has traditionally relied on a few characters now deemed to be highly homoplastic, and their classification—especially at the genus level—is yet to be consolidated based on rigorous phylogenetic analyses. Recent studies highlighted the value of genitalic trait variation in the evolution in Lampyridae, particularly for the rich and poorly known South American Photinini fauna. Here, we describe a new genus, with a new species from the Cerrado and another one from the Atlantic Forest. Phylogenetic analyses based on Bayesian and Maximum Parsimony approaches recovered these two species as sister to each other, which we place here in Zoiudo gen. nov. Males of this new lineage of fireflies are overall strikingly similar to Photinus Laporte 1833, but can be readily distinguished by traits heretofore neglected, including the structure of tibial spurs and many genitalic traits. Instead, Zoiudo gen. nov. is strongly supported as sister to Ybytyramoan Silveira and Mermudes, 2014, supported by eight synapomorphies, the most conspicuous being the sternum VIII with lateral margins divergent up to basal 1/5, then convergent posteriorly, and the rudimentary ventral plate of phallus. Our study confirms the value of extensive character and taxon sampling towards a revised classification of Photinini taxa and highlights the need for a continued sampling and protection of South American biomes.

Phylogeny of Scissicauda Species, with Eight New Species, including the First Photinini Fireflies with Biflabellate Antennae (Coleoptera: Lampyridae)

“…The subfamilial classification of lampyrids remains unsteady, and the relationships among the genera, as well as their monophyly, remain largely unexplored outside Luciolinae [3][4][5]14,20,21]. To test Scissicauda monophyly, in addition to current and putative Scissicauda species, we included in our taxon sampling representatives the four subtribes of Photinini: Pyractonema compressicornis Solier, 1849 and Pyractonema haemorrhoa Fairmaire & Germain, 1861 (Figure 17A 25P-U); in addition to the incertae sedis taxon Vesta thoracica (Olivier, 1790) (Figure 17O,P and Figure 20H), historically placed in Photinini.…”

“…A focus on taxa with bioluminescent adults has left the taxonomy of dark fireflies in especially poor condition compared to taxa with lit adults (e.g., [13]). Recent studies have been reshaping the classification of Photinini by combining recently collected materials, extensive surveys of historical collections, and phylogenetic analyses (e.g., [5,14]). These studies provided further support to the idea that sensory traits traditionally used in genus-level diagnoses of fireflies are largely homoplastic, calling for taxonomic revisions, particularly of Photinini.…”