Exploring Phylogenetic Relationships of the Mecocephala Group (Hemiptera: Pentatomidae) Using Continuous and Discrete Characters, with Notes on Taxonomy.

The Mecocephala group comprises about 50 species, restricted to the Neotropics and with the highest species richness in Neotropical South America. Several species use rice as host plants and their identification is facilitated by the presence of exaggerated head proportions and a unique male genitalic morphology. The taxonomy of the group has been extensively explored, but inferring its monophyly and especially its internal phylogenetic relationships has been challenging. Here, we inferred the phylogenetic relationships for the group assembling the most complete taxonomic sampling to date, analyzing discrete and continuous morphological characters through equal and implied weighted parsimony analyses. The monophyly of the group was recovered, but internal relationships varied slightly according to the dataset tested. Thus, we propose internal arrangements for the group and provide a formal description of the Mecocephala group, diagnoses for each genus, a dichotomous key to identify its genera, and illustrations of the morphological characters and type species.

Evolutionary and phylogenetic insights from the mitochondrial genomic analysis of Diceraeus melacanthus and D. furcatus (Hemiptera: Pentatomidae).

The mitochondrial genomes of D. melacanthus and D. furcatus were sequenced and used to investigate the phylogenetic relationships with 54 species of Pentatomidae. Their mitogenomes are 17,197 and 15,444 bp-long, respectively, including 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, and 22/21 transfer RNA genes, with conserved gene arrangement. Leu, Lys, and Ser were the most common amino acids in their PCGs. PCGs evolutionary analysis indicated their mitogenomes are under purifying selection, and the most conserved genes are from the cytochrome complex, reinforcing their suitability as markers for molecular taxonomy. We identified 490 mtSSRs in 56 Pentatomidae species, with large variation and a positive correlation between mtSSR number and genome size. Three mtSSRs were identified in each Diceraeus species. Only the mtSSR in the nad6 (D. melacanthus) and nad4 (D. furcatus) appear to have application as molecular markers for species characterization. Phylogenetic analysis confirmed the monophyly of Pentatomidae. However, our analysis challenged the monophyly of Pentatominae and Podopinae. We also detected unexpected relationships among some tribes and genera, highlighting the complexity of the internal taxonomic structure of Pentatomidae. Both Diceraeus species were grouped in the same clade with the remaining Carpocorini analyzed.

Horizontally transferred glycoside hydrolase 26 may aid hemipteran insects in plant tissue digestion.

Glycoside hydrolases are enzymes that break down complex carbohydrates into simple sugars by catalyzing the hydrolysis of glycosidic bonds. There have been multiple instances of adaptive horizontal gene transfer of genes belonging to various glycoside hydrolase families from microbes to insects, as glycoside hydrolases can metabolize constituents of the carbohydrate-rich plant cell wall. In this study, we characterize the horizontal transfer of a gene from the glycoside hydrolase family 26 (GH26) from bacteria to insects of the order Hemiptera. Our phylogenies trace the horizontal gene transfer to the common ancestor of the superfamilies Pentatomoidea and Lygaeoidea, which include stink bugs and seed bugs. After horizontal transfer, the gene was assimilated into the insect genome as indicated by the gain of an intron, and a eukaryotic signal peptide. Subsequently, the gene has undergone independent losses and expansions in copy number in multiple lineages, suggesting an adaptive role of GH26s in some insects. Finally, we measured tissue-level gene expression of multiple stink bugs and the large milkweed bug using publicly available RNA-seq datasets. We found that the GH26 genes are highly expressed in tissues associated with plant digestion, especially in the principal salivary glands of the stink bugs. Our results are consistent with the hypothesis that this horizontally transferred GH26 was co-opted by the insect to aid in plant tissue digestion and that this HGT event was likely adaptive.

Phylogenomics of endemic Australian Ulopinae (Hemiptera: Cicadomorpha: Cicadellidae).

Ulopinae is a distinctive subfamily of leafhoppers that is widely distributed across the Afrotropical, Palearctic, Indomalayan and Australasian regions. The ulopine fauna of Australia is entirely endemic and includes two tribes of striking appearance, the Ulopini and Cephalelini. Knowledge of these groups is fragmentary and in many instances, no information is available beyond original descriptions. We assess the monophyly, phylogenetic placement and species-level diversity of the Ulopini genus Austrolopa . Phylogenetic analyses based on sequence data from target nuclear loci (18S , 28S , H2A and H3 ) and mitochondrial genomes (15 genes) for 23 membracoid taxa yielded congruent topologies. Our results provide strong evidence for the monophyly of Ulopinae and a clade consisting of Ulopini + Cephalelini. However, a non-monophyletic Cephalelini arises from within a polyphyletic Ulopini. Austrolopa was strongly recovered as monophyletic in all analyses, a result also supported by morphological features. The genus currently includes six species, three of which are described based on morphological and molecular data: Austrolopa botanica , sp. nov. , Austrolopa rotunda , sp. nov. and Austrolopa sublima , sp. nov. A lectotype designation is provided for Austrolopa kingensis Evans, 1937, sp. reval. Our findings illustrate that the Australian Ulopinae is far more diverse than currently circumscribed and several species of Austrolopa are yet to be recognised. ZooBank: urn:lsid:zoobank.org:pub:1480285B-8F61-4659-A929-2B1EF3168868.

Improving DNA barcoding library of armored scale insects (Hemiptera: Diaspididae) in China.

DNA barcoding is used to identify cryptic species, survey environmental samples, and estimate phyletic and genetic diversity. Armored scale insects are phytophagous insects and are the most species-rich taxa in the Coccoidea superfamily. This study developed a DNA barcode library for armored scale insect species collected from southern China during 2021-2022. We sequenced a total of 239 specimens, recognized as 50 morphological species, representing two subfamilies and 21 genera. Sequencing analysis revealed that the average G + C content of the cytochrome oxidase subunit I (COI) gene sequence was very low (~18.06%) and that the average interspecific divergence was 10.07% while intraspecific divergence was 3.20%. The intraspecific divergence value was inflated by the high intraspecific divergence in ten taxa, which may indicate novel species overlooked by current taxonomic treatments. All the Automated Barcode Gap Discovery, Assemble Species by Automatic Partitioning, Taxon DNA analysis and Bayesian Poisson Tree Process methods yielded largely consistent results, indicating a robust and credible species delimitation. Based on these results, an intergeneric distance threshold of ≤ 5% was deemed appropriate for the differentiation of armored scale insect species in China. This study establishes a comprehensive barcode library for the identification of armored scale insects, future research, and application.

Revisionary notes on the genus Adelungia Melichar, 1902 (Hemiptera: Cicadellidae, Megophthalminae), with the description of a new genus.

Leafhopper genus Adelungia Melichar, 1902 is reviewed. Spathicerula Gnezdilov gen. nov. is described with Adelungia calligoni Oshanin, 1908 as the type species, and a new combination-Spathicerula calligoni (Oshanin, 1908), comb. nov., is proposed. Adelungia tridigitata Dlabola, 1984 is placed in synonymy under A. calligoni. Lectotypes are designated for Adelungia elegans Melichar, 1902 and A. breviceps Kusnezov, 1931 to stabilize the nomenclature in the group according to the International Code of Zoological Nomenclature.

Toward a new classification of planthoppers Hemiptera Fulgoromorpha: 2. Higher taxa, their names and their composition.

A synthesis of planthopper suprafamilial and familial classification is provided and discussed, solving some nomenclatural issues for the group, and adopting an enriched presentation with a clear distinction between the taxon name and its concept.

A new genus and species of giant mealybugs (Hemiptera: Coccomorpha: Monophlebidae) from eastern China.

A new genus of giant mealybugs (Hemiptera: Coccomorpha; Monophlebidae), Coronaproctus Li, Xu & Wu gen. nov., is established for the species Coronaproctus castanopsis Li, Xu & Wu sp. nov., collected from Zhejiang province, China on the twigs of Castanopsis eyrei (Fagaceae). The adult female and male are described and illustrated. The new genus is characterized by the adult female possessing quadrilocular disc pores, 13 cicatrices on the venter, and a U-shaped opening of the marsupium, but lacking large bilocular pores.

A new species of planthopper from Costa Rica in the genus Herpis (Hemiptera: Derbidae) from palms in the cloud forest.

Recent survey efforts in Costa Rica have documented many new species of planthoppers, primarily in the families Derbidae and Cixiidae, on palms. Recently, a specimen was collected sweeping palms in the Los Angeles cloud forest in Costa Rica and was identified as belonging to the genus Herpis (Derbidae). It was subsequently determined to represent a previously undescribed species. Herein, the new species, Herpis circumsoros Bahder & Bartlett sp. n. is described with supplemental molecular data for the cytochrome c oxidase subunit I (COI) gene and 18S rRNA gene to support placement of the new species in the genus Herpis.

A new genus, Duffelsa gen. n., with descriptions of three new species and one new combination (Hemiptera: Cicadidae).

One new cicada genus, Duffelsa gen. n., is erected in the tribe Leptopsaltriini Moulton, 1923, with the designation of Pomponia orientalis (Distant, 1912) as the type species. Three new species, D. parvula sp. n., D. grandia sp. n. and D. rubida sp. n., are described from China. A key to species of Duffelsa gen. n. is provided. The relationship of this new genus to related taxa is discussed.

Review of Cyphotes Burmeister, 1835 (Hemiptera: Membracidae) with the description of a related new genus.

The Neotropical treehopper genus Cyphotes Burmeister, 1835 (= Aspona Stal, 1862 syn. nov.) is redefined. Cyphotes contains only two species, the type species Cyphotes nodosa Burmeister, 1835 (= Aspona bullata Stl, 1862 syn. nov.) and Cyphotes quadrinodosa (Fonseca & Diringshofen, 1969) reinstated. comb. Allocyphotes gen. nov. (type species Cyphotes insolita Goding, 1929) is proposed to accommodate two other species previously placed in Cyphotes, Allocyphotes pompanoni (Boulard, 2011) comb. nov. and Allocyphotes colombiensis (Gonzlez-Mozo, 2017) comb. nov., and three new species from Ecuador: A. flavus sp. nov., A. waoraniorum sp. nov and A. robertoi sp. nov. for a total of six species. Illustrations, including genitalia images, new locality records and keys to genera and species are provided.

A new species of planthopper in the genus Anchimothon (Hemiptera: Auchenorrhyncha: Derbidae) on palms from Costa Rica.

Anchimothon is a small genus of derbid planthoppers known from Mesoamerica and northern South America. Recent survey efforts in the Caribbean basin have documented many new taxa of fulgoroids from palms. During this survey, a novel taxon identified as Anchimothon was collected from palm seedlings at La Selva Biological Station in Costa Rica. Here, the novel taxon is described as A. myriei sp. n. with molecular data for the cytochrome c oxidase subunit I (COI) and18S rRNA providing support for placement of the new species in Anchimothon. An updated key is provided for the current species of Anchimothon.

Microbiome analyses of 12 psyllid species of the family Psyllidae identified various bacteria including Fukatsuia and Serratia symbiotica, known as secondary symbionts of aphids.

BACKGROUND: Psyllids (Hemiptera: Psylloidea) comprise a group of plant sap-sucking insects that includes important agricultural pests. They have close associations not only with plant pathogens, but also with various microbes, including obligate mutualists and facultative symbionts. Recent studies are revealing that interactions among such bacterial populations are important for psyllid biology and host plant pathology. In the present study, to obtain further insight into the ecological and evolutionary behaviors of bacteria in Psylloidea, we analyzed the microbiomes of 12 psyllid species belonging to the family Psyllidae (11 from Psyllinae and one from Macrocorsinae), using high-throughput amplicon sequencing of the 16S rRNA gene. RESULTS: The analysis showed that all 12 psyllids have the primary symbiont, Candidatus Carsonella ruddii (Gammaproteobacteria: Oceanospirillales), and at least one secondary symbiont. The majority of the secondary symbionts were gammaproteobacteria, especially those of the family Enterobacteriaceae (order: Enterobacteriales). Among them, symbionts belonging to "endosymbionts3", which is a genus-level monophyletic group assigned by the SILVA rRNA database, were the most prevalent and were found in 9 of 11 Psyllinae species. Ca. Fukatsuia symbiotica and Serratia symbiotica, which were recognized only as secondary symbionts of aphids, were also identified. In addition to other Enterobacteriaceae bacteria, including Arsenophonus, Sodalis, and "endosymbionts2", which is another genus-level clade, Pseudomonas (Pseudomonadales: Pseudomonadaceae) and Diplorickettsia (Diplorickettsiales: Diplorickettsiaceae) were identified. Regarding Alphaproteobacteria, the potential plant pathogen Ca. Liberibacter europaeus (Rhizobiales: Rhizobiaceae) was detected for the first time in Anomoneura mori (Psyllinae), a mulberry pest. Wolbachia (Rickettsiales: Anaplasmataceae) and Rickettsia (Rickettsiales: Rickettsiaceae), plausible host reproduction manipulators that are potential tools to control pest insects, were also detected. CONCLUSIONS: The present study identified various bacterial symbionts including previously unexpected lineages in psyllids, suggesting considerable interspecific transfer of arthropod symbionts. The findings provide deeper insights into the evolution of interactions among insects, bacteria, and plants, which may be exploited to facilitate the control of pest psyllids in the future.

New genera and species of felt scales (Hemiptera: Coccomorpha: Eriococcidae), with descriptions of new species and immature instars of described species.

In this work, emphasis is placed on the Eriococcidae (Hemiptera: Coccomorpha) of the Nearctic Region including the immature instars of many species not previously described, two new genera (Carphococcus Miller and Stocks and Ypofloiococcus Miller and Stocks), and 11 new species (Acanthococcus pennyae Miller and Stocks, Carph. apodus Miller and Stocks, Carpochloroides eugeniae Miller and Stocks, Ovaticoccus betsyae Miller and Stocks, Ov. gordoni Miller and Stocks, Ov. haigi Miller and Stocks, Ov. maryfoleybensonae Miller and Stocks, Ov. telotrichus Miller and Stocks, Ov. tuttlei Miller and Stocks, Ov. villanuevorum Miller and Stocks and Y. libeauae Miller and Stocks). In addition to the new taxa, descriptions and illustrations are provided for adult females, adult males and/or immature instars of Ac. arenosus (Cockerell), Ac. coccineus (Cockerell), Ac. dennoi Miller and Miller, Ac. gallicolus (Cockerell & Rohwer), Ac. hoyi Miller and Miller, Ac. kemptoni (Parrott), Apezococcus idiastes Ferris, Carpo. mexicanus Ferris, Cryptococcus fagisuga Lindinger, Cr. williamsi Kosztarab and Hale, Hypericicoccus hyperici (Ferris), Ov. agavacearum Pellizzari and Kozár, Ov. agavium (Douglas), Ov. cornutus (Ferris), Ov. densus (Miller), Ov. eriogoni (Miller), Ov. exoticus Pellizzari and Kozár, Ov. neglectus (Cockerell), Ov. peruvianus (Granara de Willink & Díaz), Ov. salviae Miller, Ov. sanguineus (Miller), Ov. tippinsi Miller and Miller, Ov. variabilis Miller, Spiroporococcus braggi (Cockerell & Robinson), S. yuccae (Ferris) and Xerococcus foquieriae Ferris. Lectotype designations are made for Ap. idiastes. Carpo, mexicanus and H. hyperici. New collection data are provided for Ov. californicus McKenzie, Ov. johnsoni (Miller), Ov. mackenziei Miller, Ov. parvispina (Chaffin) and Ov. viscosa (Kondo). Dichotomous keys are given for: determination of most eriococcid instars of both sexes; Nearctic genera of the Eriococcidae based on adult females; adult females, second-instar females, second-instar males, and first-instar nymphs of Ovaticoccus Kloet 1944; and the seven species of Acanthococcus Signoret 1875 treated here, based on first-instar nymphs. Oregmopyga Hoy 1963 and Cornoculus Ferris 1955 are treated as junior subjective synonyms of Ovaticoccus. Atriplicia Cockerell and Rohwer 1909 has been placed previously as a junior synonym of Eriococcus but here is regarded as a junior subjective synonym of Acanthococcus. We treat 44 species; new descriptions are provided for 101 treated instars, and detailed line drawings are given for all but three of them. The following species, listed in ScaleNet as occurring in the Nearctic Region, are transferred to Acanthococcus from Eriococcus Targioni Tozzetti 1868: Acanthococcus actius Miller and Miller 1993 rev. comb.; Ac. arenariae Miller and Miller 1993 rev. comb.; Ac. barri Miller 1991 rev. comb.; Ac. beshearae Miller and Miller 1993 rev. comb.; Ac. dennoi Miller and Miller 1993 rev. comb.; Ac. droserae Miller, Liu and Howell 1992 rev. comb.; Ac. epacrotrichus Miller and Miller 1992 rev. comb.; Ac. froebeae Miller 1991 rev. comb.; Ac. gallicolus (Cockerell & Rohwer 1909) comb. n.; Ac. hoyi Miller and Miller 1992 rev. comb.; Ac. mackenziei Miller and Miller 1992 rev. comb.; Ac. macrobactrus Miller and Miller 1992 rev. comb.; Ac. megaporus Miller and Miller 1993 rev. comb.; A. mesotrichus Miller and Miller 1993 rev. comb.; Ac. microtrichus Miller and Miller 1992 rev. comb.; Ac. monotrichus Miller and Miller 1993 rev. comb.; Ac. ophius Miller and Miller 1993 rev. comb.; Ac. stauroporus Miller and Miller 1992 rev. comb.; Ac. washingtonensis Miller and Miller 1992 rev. comb.; and Ac. whiteheadi Miller 1991 rev. comb. In addition, two species are transferred to Acanthococcus from Rhizococcus Signoret: Ac. coccineus (Cockerell 1894a) rev. comb. and Ac. kemptoni (Parrott 1900) rev. comb. Three images of water color paintings by Mary Foley Benson are included.

Five new Brazilian species of Fuminana Freytag (Hemiptera: Cicadellidae: Gyponini) with new records and key to males.

Five new Brazilian species of Fuminana Freytag, 1989 are described and illustrated: F. diaphana sp. nov. from states of Maranhão and Piauí, F. guaricica sp. nov. from Paraná State, F. incurvata sp. nov. and F. retorta sp. nov. from Rondônia State, and F. niluga sp. nov. from states of Acre, Pará, Rondônia and Mato Grosso. The female genitalia is described and illustrated for the first time and a revised genus description is presented. New distribution records are given and seven species are newly recorded from Brazil: F. astra (DeLong & Freytag, 1969), F. conspicua (DeLong & Freytag, 1969), Fuminana curra (DeLong & Freytag, 1969), F. extata Freytag, 1989, F. jaculum (DeLong & Freytag, 1969), F. signa (DeLong & Freytag, 1969) and F. superba (DeLong & Freytag, 1969). A key to males is provided as well as some taxonomic notes about the genus.

Complete mitochondrial genome sequencing of Oxycarenus laetus (Hemiptera: Lygaeidae) from two geographically distinct regions of India.

Oxycarenus laetus is a seed-sap sucking pest affecting a variety of crops, including cotton plants. Rising incidence and pesticide resistance by O. laetus have been reported from India and neighbouring countries. In this study, O. laetus samples were collected from Bhatinda and Coimbatore (India). Pure mtDNA was isolated and sequenced using Illumina MiSeq. Both the samples were found to be identical species (99.9%), and the complete genome was circular (15,672 bp), consisting of 13 PCGs, 2 rRNA, 23 tRNA genes, and a 962 bp control region. The mitogenome is 74.1% AT-rich, 0.11 AT, and - 0.19 GC skewed. All the genes had ATN as the start codon except cox1 (TTG), and an additional trnT was predicted. Nearly all tRNAs folded into the clover-leaf structure, except trnS1 and trnV. The intergenic space between trnH and nad4, considered as a synapomorphy of Lygaeoidea, was displaced. Two 5 bp motifs AATGA and ACCTA, two tandem repeats, and a few microsatellite sequences, were also found. The phylogenetic tree was constructed using 36 mitogenomes from 7 super-families of Hemiptera by employing rigorous bootstrapping and ML. Ours is the first study to sequence the complete mitogenome of O. laetus or any Oxycarenus species. The findings from this study would further help in the evolutionary studies of Lygaeidae.

Morphological reassessment of the movable calcar of delphacid planthoppers (Hemiptera: Fulgoromorpha: Delphacidae).

This study presents the morphology of calcar in adult Delphacidae based on representatives of the genera Ugyops Guérin-Meneville, 1834, Notuchus Fennah, 1969 (Ugyopini), Asiraca Latreille, 1798 (Asiracini), Kelisia Fieber, 1866, (Kelisini), Stenocranus Fieber, 1866 (Stenocranini), Chloriona Fieber, 1866, Megadelphax Wagner, 1963, Muellerianella Wagner, 1963, Javesella Fennah, 1963, Conomelus Fieber, 1866, Euconomelus Haupt, 1929, Hyledelphax Vilbaste, 1968, Stiroma Fieber, 1866, Struebingianella Wagner, 1963 and Xanthodelphax Wagner, 1963 (Delphacini). We used SEM electron microscopy, to define seven types of calcar structure (Types 1, 2, 5, 6, 7, 8, and 9) based on combinations of characters including shape, number of teeth and differentiation of sensory structures in species from fifteen genera. Additionally, two other types (Types 3 and 4) were determined based on the calcar descriptions from previous studies. Similarities and differences in calcar structure and function were discussed and emerging relationships between planthopper species and their particular habitats were indicated.

Cytotype Affects the Capability of the Whitefly Bemisia tabaci MED Species To Feed and Oviposit on an Unfavorable Host Plant.

The acquisition of nutritional obligate primary endosymbionts (P-symbionts) allowed phloemo-phageous insects to feed on plant sap and thus colonize novel ecological niches. P-symbionts often coexist with facultative secondary endosymbionts (S-symbionts), which may also influence their hosts' niche utilization ability. The whitefly Bemisia tabaci is a highly diversified species complex harboring, in addition to the P-symbiont "Candidatus Portiera aleyrodidarum," seven S-symbionts whose roles remain poorly understood. Here, we compare the phenotypic and metabolic responses of three B. tabaci lines differing in their S-symbiont community, reared on three different host plants, hibiscus, tobacco, or lantana, and address whether and how S-symbionts influence insect capacity to feed and produce offspring on those plants. We first show that hibiscus, tobacco, and lantana differ in their free amino acid composition. Insects' performance, as well as free amino acid profile and symbiotic load, were shown to be plant dependent, suggesting a critical role for the plant nutritional properties. Insect fecundity was significantly lower on lantana, indicating that it is the least favorable plant. Remarkably, insects reared on this plant show a specific amino acid profile and a higher symbiont density compared to the two other plants. In addition, this plant was the only one for which fecundity differences were observed between lines. Using genetically homogeneous hybrids, we demonstrate that cytotype (mitochondria and symbionts), and not genotype, is a major determinant of females' fecundity and amino acid profile on lantana. As cytotypes differ in their S-symbiont community, we propose that these symbionts may mediate their hosts' suitable plant range. IMPORTANCE Microbial symbionts are universal in eukaryotes, and it is now recognized that symbiotic associations represent major evolutionary driving forces. However, the extent to which symbionts contribute to their hosts' ecological adaptation and subsequent diversification is far from being fully elucidated. The whitefly Bemisia tabaci is a sap feeder associated with multiple coinfecting intracellular facultative symbionts. Here, we show that plant species simultaneously affect whiteflies' performance, amino acid profile, and symbiotic density, which could be partially explained by differences in plant nutritional properties. We also demonstrate that, on lantana, the least favorable plant used in our study, whiteflies' performance is determined by their cytotype. We propose that the host plant utilization in B. tabaci is influenced by its facultative symbiont community composition, possibly through its impact on the host dietary requirements. Altogether, our data provide new insights into the impact of intracellular microorganisms on their animal hosts' ecological niche range and diversification.

Taxonomic study of the leafhopper genus Anufrievia Dworakowska (Hemiptera: Cicadellidae: Typhlocybinae: Erythroneurini) from China, with descriptions of two new species.

The genus Anufrievia Dworakowska is reviewed with two new species from China: A. anchoroides sp. nov., and A. drepanoides sp. nov.. Detailed morphological descriptions and illustrations of these two new species and a key to all known species (males) from China are provided.