Search Results (6)

Mitochondrial genomes are widely used in insect taxonomy and phylogenetics, but their signals may conflict with morphology and nuclear genomic evidence because the mitochondrial genome represents a single maternally inherited locus. Here, we assembled complete mitochondrial genomes of four pygmy grasshoppers, Zhengitettix transpicula, Formosatettix sp., Gibbotettix parvipulvillus, and Bolivaritettix sp., using PacBio HiFi reads. The four mitogenomes ranged from 15,152 to 17,976 bp and contained the typical 37 mitochondrial genes. Mitochondrial phylogenies inferred by maximum likelihood and Bayesian methods were topologically identical and recovered several well-supported tetrigid relationships, including a close relationship between Formosatettix sp. and Bolivaritettix sp. However, Z. transpicula was unexpectedly placed near Macromotettixoides rather than close to other Zhengitettix representatives. In contrast, a morphology-based tree recovered Z. transpicula with Z. triangularis, and comparison with a published nuclear single-copy ortholog tree based on 1962 loci supported a non-mitochondrial placement of Zhengitettix inconsistent with the anomalous mitochondrial position of Z. transpicula. Independent assembly from the original HiFi reads, read-depth inspection, protein-coding gene checks, and nuclear-genome screening for NUMT-like sequences supported the authenticity of the assembled Z. transpicula mitogenome. These results document mito–nuclear and cyto-morphological discordance in Tetrigidae and highlight the need for integrative interpretation of mitochondrial phylogenies in taxonomically complex insect groups. Full article

A new genus, Ingrischana gen. nov. (Tetrigidae: Tetriginae) is established for winged Tetriginae from Asia with extremely setose mid femur, and toothed dorsal margin of the hind femur. Till now, many species of this genus have been erroneously assigned to the genera Bannatettix Zheng, 1993; Formosatettixoides Zheng, 1994; Ergatettix Kirby, 1914; Euparatettix Hancock, 1904; Paratettix Bolívar, 1887, and Tetrix Latreille, 1802. Altogether 2 new species, 11 new combinations, 1 new name, and 2 new synonyms are proposed, and 1 species is reinstated. Two new species are I. motbotawa gen. et sp. nov. (Brija Furry Groundhopper) and I. aspinosa gen. et sp. nov. (Toothless Furry Groundhopper), both from Nepal. New combinations are I. aptera (Zheng et Ou, 2009) comb. nov., I. barbifemura (Zheng, 1998) comb. nov., I. curvimargina (Zheng et Deng, 2004) comb. nov., I. dentifemura (Zheng, Shi et Luo, 2003) comb. nov., I. grossifemura (Zheng et Jiang, 1997) comb. nov., I. longzhouensis (Zheng et Jiang, 2000) comb. nov., I. obesa (Bolívar, 1887) comb. nov., I. serrifemora (Deng, Zheng et Wei, 2008) comb. nov., I. serrifemoralis (Zheng, 1998) comb. nov., I. serrifemoroides (Zheng et Jiang, 2002) comb. nov., and I. torulosinota (Zheng, 1998) comb. nov. The new name is I. parlungana nom. nov., proposed for Bannatettix serrifemoralis Zheng et Shi, 2009a, because of the homonymy with I. serrifemoralis (Zheng, 1998) comb. nov. Ingrischana jhapana (Ingrisch, 2001a) stat. rev. et comb. nov. is reinstated as a valid species. Two new synonyms are Formosatettixoides guangxiensis Zheng & Jiang, 2000 syn. nov. (of I. longzhouensis comb. nov.), and Ergatettix serifemoroides Zheng et Shi, 2009b syn. nov. (of I. parlungana nom. nov.). The new genus is defined not only by morphological apomorphies, but is also confirmed by mitogenome phylogeny. Full article

The Philippines and the Papuan archipelagos harbor a vast diversity of pygmy grasshoppers, including the pygmy devils of the genera Xistra and Tegotettix, as well as visually similar taxa reviewed in this study. A new tribe, two new genera, a new subgenus, three new species, and 24 new or resurrected taxonomic combinations are proposed in this study. A new colorful wingless genus and species, Almacris alleochroa gen. et sp. nov., is described from Mindanao. Taxonomic reshuffling of the genus Xistra is performed—a new subgenus is described, Tegoxistra subgen. nov., to include X. derijei, X. corniculata, and X. cristifera, while the nominotypical subgenus becomes restricted to X. gogorzae and X. sagittaria. All other species previously assigned to Xistra are herewith moved to Xistrella, resulting in 20 new combinations. The genus Ginixistra gen. nov. (Exanimini)—whose members show remarkable similarity to Fiji-endemic Fijixistra—is described for G. novaeguineae, G. davorkae sp. nov., and G. novaebritanniae sp. nov. from New Guinea and New Britain. The new tribe Xistrellini trib. nov. is established to accommodate Afrosystolederus, Bannatettix, Kanakacris, Phaesticus, Pseudoparatettix, Pseudosystolederus, Pseudoxistrella, Synalibas, Systolederus, Teredorus, and Xistrella. Previous molecular phylogenetic studies have confirmed Xistrellini monophyly and suggested that the ancestor of this tribe may have originated during the Cretaceous period, approximately 127–100 million years ago (mya). Full article

Tetrigidae is one of the largest orthopteran families, but very few studies so far have integrated molecular and morphological data. Unsurprisingly, few species have been DNA barcoded, and the unresolved taxonomy makes Tetrigidae a difficult group to work with. Here, we examined a sample of 90 specimens collected as a part of the Costa Rican DNA barcoding project and identified 20 species assigned to 24 BINs, among which are 8 newly described species: Scaria bimaculata sp. nov., Lophotettix semicristatus sp. nov., Otumba auricarinata sp. nov., Otumba tenuis sp. nov., Otumba ignicula sp. nov., Metrodora mollilobata sp. nov., Metrodora ala sp. nov., and Platythorus inabsolutus sp. nov. We found that coloration and lateral lobe shape are species-specific among the examined species of Batrachideinae and Metrodorinae and that Lophotettiginae and Metrodora might be more closely related than previously assumed. Full article

The pygmy grasshopper, Zhengitettix transpicula, is a Chinese endemic species with an exceedingly limited distribution and fragile population structure, rendering it vulnerable to extinction. We present a high-continuity, chromosome-scale reference genome assembly to elucidate this species’ distinctive biology and inform conservation. Employing an integrated sequencing approach, we achieved a 970.40 Mb assembly with 96.32% coverage across seven pseudo-chromosomes and impressive continuity (N50 > 220 Mb). Genome annotation achieves identification with 99.2% BUSCO completeness, supporting quality. Comparative analyses with 14 genomes from Orthoptera-facilitated phylogenomics and revealed 549 significantly expanded gene families in Z. transpicula associated with metabolism, stress response, and development. However, genomic analysis exposed remarkably low heterozygosity (0.02%), implying a severe genetic bottleneck from small, fragmented populations, characteristic of species vulnerable to extinction from environmental disruptions. Elucidating the genetic basis of population dynamics and specialization provides an imperative guideline for habitat conservation and restoration of this rare organism. Moreover, divergent evolution analysis of the CYP305m2 gene regulating locust aggregation highlighted potential structural and hence functional variations between Acrididae and Tetrigidae. Our chromosomal genomic characterization of Z. transpicula advances Orthopteran resources, establishing a framework for evolutionary developmental explorations and applied conservation genomics, reversing the trajectory of this unique grasshopper lineage towards oblivion. Full article

Mitochondrial genomes offer pragmatic genetic markers to reconstruct evolutionary relationships and inform taxonomic classifications. Here, we present complete mitochondrial sequences for four Chinese pygmy grasshoppers (Tetrigidae), aiming to reevaluate phylogenetic patterns and morphological taxonomy. Our 17,643 bp, 16,274 bp, 15,086 bp, and 15,398 bp mitogenomes of Exothotettix guangxiensis, Formosatettix longwangshanensis, Euparatettix sinufemoralis and Systolederus zhengi, respectively, exhibit archetypal Tetrigidae architecture. We constructed phylogenies using 13 protein-coding loci from 39 Tetrigidae mitogenomes, revealing several genus-level clusters with statistically solid support, conflicts regarding Ex. guangxiensis, F. longwangshanensis merging into Tetrix, and two subclades of Systolederus. The dated divergence analysis indicates over 150 Mya of Tetrigidae ancestry, tracing the Systolederus generic group splits up to ~75 million years ago. Moreover, the Tetrix generic group radiated over 14 Mya across vast distributions, consistent with rapid adaptive dispersals. Our mitochondrial reconstructions suggest that Synstolederus is taxonomically overextended for a single genus, while the distinctiveness of Ex. guangxiensis and F. longwangshanensis from Tetrix appears questionable, and the Tetrix generic group comprises a potential tRNA-Ile coding region. Our integrative mitogenomic approaches will help resolve issues stemming from morphological taxonomy that is reliant on traits that are prone to convergence. This investigation enhances comprehension of Tetrigidae phylogeny and accentuates molecular systematics. Full article