The fifth family of the true crickets (Insecta: Orthoptera: Ensifera: Grylloidea), Oecanthidae defin. nov.: phylogenetic relationships and divergence times

Abstract

Crickets are frequently used as a model in several areas of science, including acoustic communication, behaviour and neurobiology. However, only a few of these studies are placed in an evolutionary framework due to the limited number of phylogenetic hypotheses for true crickets. We present a phylogenetic hypothesis for a newly defined family of crickets, Oecanthidae defin. nov., sister-group of Gryllidae defin. nov. The phylogenetic analyses are based on molecular and morphological data under likelihood and parsimony criteria and molecular data for divergence-times estimation (Bayesian inference). We used 107 terminals from all biogeographic regions and six fossils for the time calibration of the tree. All analyses resulted in Oecanthidae with four subfamilies: Euscyrtinae, Oecanthinae defin. nov., Podoscirtinae defin. nov. and Tafaliscinae defin. nov. Based on our results, we revise the definition and internal classifications of the subfamilies, supertribes and tribes. A new tribe, Phyllogryllini trib. nov. is described. We also update their diagnoses, list the genera of the tribes and list their apomorphies. We provide an identification key for all suprageneric taxa of Oecanthidae, plus all genera of Tafaliscinae. Finally, we discuss the phylogenetic relationships of Oecanthidae, their divergence times, habitat diversity and the importance of ovipositor variation in this clade.

New Cretaceous crickets of the subfamilies Nemobiinae and Podoscirtinae (Orthoptera, Grylloidea: Trigonidiidae, Oecanthidae) attest the antiquity of these clades

“…We follow the phylogenetic classification proposed by Chintauan-Marquier et al (2013; 2016, figs 5, 6). Using a large dataset of molecular and morphological characters for a large taxonomic sampling, Campos et al (2022) validate the family status of both clades F and G, as Oecanthidae and Gryllidae respectively; a complete reanalysis of the classification of Oecanthidae on the basis of morphological apomorphies leads to splitting the Oecanthidae into four subfamilies, i.e. Euscyrtinae, Podoscirtinae (Hapithidi þ Podoscirtidi), Oecanthinae (Oecanthidi þ Diatrypidi) and Tafaliscinae (Paroecanthidi þ Tafaliscidi).…”

“…subfamily Gryllidae Eneopterinae (Vicente et al 2017 and references therein) or its tribes (Tan et al 2021), the Neotropical Phalangopsidae genus Eidmanacris Chopard, 1956(Campos et al 2021, the Hawaiian trigonidiine genus Nudilla Gorochov, 1988(Mendelson & Shaw, 2005, under the name Laupala Otte, 1994) or the eneopterine genus Cardiodactylus de Haan, 1844 (Dong et al 2018); He et al (2020), Shen et al (2020) and Ding et al (2021) studied the relationships of Chinese species of Trigonidiidae Trigonidiinae and Nemobiinae respectively. More recently, Campos et al (2022) studied the phylogeny of clade F of Chintauan-Marquier et al (2016), one of the two clades constitutive of the family Gryllidae, using both morphological and molecular characters in a worldwide perspective: these authors proposed to elevate clade F to family rank, i.e. the Oecanthidae, and propose a revised classification based on well-diagnosed monophyletic entities from family to tribes and genera (Campos et al 2022): crickets are now distributed into five monophyletic families.…”

“…More recently, Campos et al (2022) studied the phylogeny of clade F of Chintauan-Marquier et al (2016), one of the two clades constitutive of the family Gryllidae, using both morphological and molecular characters in a worldwide perspective: these authors proposed to elevate clade F to family rank, i.e. the Oecanthidae, and propose a revised classification based on well-diagnosed monophyletic entities from family to tribes and genera (Campos et al 2022): crickets are now distributed into five monophyletic families. Nevertheless, there is a strong deficiency of phylogenetic studies for crickets at a scale allowing the drawing of phylogenybased classifications along with clade diagnosis (see Tan et This situation is made even more complicated by the variations of cricket classification through time and among the authors.…”

“…The fossils we describe here belong to the families Trigonidiidae and Oecanthidae respectively. We use the diagnoses proposed by Desutter-Grandcolas et al (2021) for Trigonidiidae and its two well-supported and well-characterized subfamilies Trigonidiinae and Nemobiinae, and those proposed by Campos et al (2022) for Oecanthidae and its subdivisions from subfamilies to tribes. The reference classification of Cigliano et al (2022b) is now congruent with the phylogenetic classification of Campos et al (2022).…”

“…Within Oecanthidae sensu Campos et al (2022), Picogryllus Josse and Desutter-Grandcolas, gen. nov. is excluded from Euscyrtinae by fastigium not flattened dorsally, forewings with developed stridulatory apparatus, hind tibia with at most five subapical spurs (more than six in Euscyrtinae), and inner margin of claws smooth (serrated in Euscyrtinae). It is excluded from Oecanthinae sensu Campos et al (2022) by having inner ventral apical spur of hind tibiae well-developed (regressed or absent in Oecanthinae), forewing apical field well-developed although slightly shorter than mirror (reduced or absent in Oecanthinae), lateral field of forewings perpendicular to dorsal field in anterior and posterior views (forming an acute angle in Oecanthinae), and tarsal claws simple (bifid in Oecanthinae). It can be excluded from Tafaliscinae as its fastigium is wider than antennal scape in frontal view, its stridulatory file is not sinuous, and spines are absent between subapical spurs of hind tibiae.…”