Phylogeny, systematics and evolution of calling songs of the Lebinthini crickets (Orthoptera, Grylloidea, Eneopterinae), with description of two new genera

Abstract

AbstractThe Lebinthini crickets are distributed in Southeast Asia, Western Pacific and tropical South America. They represent more than half of the described species in the subfamily Eneopterinae. These crickets are morphologically and behaviorally diverse, varying in body size, wing morphology (ranging from brachypterous to fully winged) and acoustic signals. They also have a distinctive communication system: high‐frequency calling, vibratory signalling, duetting, and lack of phonotaxis in females. To investigate how these traits evolved and diversified, a clear phylogenetic context is needed with taxonomic and biological data for as many species as possible. Since 2010, the numbers of known species and genera in the tribe have grown considerably, but the type genus Lebinthus and the tribe classification lacked a general revision based on phylogenetic inferences. In this paper, we study the systematics of the Lebinthini and present new phylogenetic results confirming the monophyly of Lebinthini and the relationships established by previous studies. The phylogeny allows us to define three monophyletic subtribes within the Lebinthini with clear morphological features and distribution areas: Cardiodactylina subtribe n., Lebinthina subtribe n., and Ligypterina subtribe n. We also redefine Lebinthus and described two new genera related to Lebinthus, Falcerminthus gen.nov., and Fadinthus gen.nov., each characterized by clear‐cut morphological, anatomical, and acoustic features. Using ancestral state reconstructions, we investigate the evolution of the diverse calling songs in Lebinthini. We demonstrate that both trills and monosyllabic calls were acquired multiple times instead of evolving from simple to complex temporal patterns as suggested from previous studies. We also find that temporal traits and the dominant frequency evolve in a very dynamic way, and that the harmonic of the call, i.e., the dominant frequency, seems to undergo diversification in the subtribe Lebinthina.