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Oribatid mites (Acari, Oribatida) are a large group of soil animals, with small body sizes and complex morphological structures. At present, oribatid mite species identification is essentially based on morphological characters. In this study, we collected 124 specimens of oribatid mites belonging to 110 species of 72 genera in Russia, and extracted their genomic DNA subsequently. In order to investigate whether the molecular data (DNA-barcoding marker, COI gene) and morphological classification results are consistent, we used three methods, ASAP, ABGD and GMYC, to delimit species, and calculate a maximum likelihood tree. The results indicate that COI gene fragments can be effectively used for species delimitation. There are some cryptic species identified in oribatid mites, which do not have distinct morphological differences, but diverge considerably in molecular data. Meanwhile, some formerly unidentified species could be identified through molecular means. The study enriches the molecular data of oribatid mites worldwide and provides the basis for more detailed taxonomic studies of oribatid mites in Russia. In the future, more analyses and mining of molecular data, combined with morphological analyses, will help to reveal and further understand the phylogenetic relationships of Oribatida. [ABSTRACT FROM AUTHOR]

Tuning catalytic centers in heterogeneous catalyst, both in a chemical and a spatial manner, is a powerful approach to improve the stability and the efficiency of catalysts. While the chemical aspects are largely understood, the spatial interactions around active sites, comprised of non‐covalent interactions, are difficult to maintain and challenging to study. Herein, the unique properties of covalent organic frameworks (COFs) are utilized to establish an ideal reaction environment for the hydrolysis of cellobiose and other common disaccharides in mild, metal‐free, and neutral aqueous conditions. The chosen COF, HCl‐PSA‐IM‐COF‐OMe ("HCl" for hydrochloric acid, "PSA" for propyl sulfonic acid, "IM" for imidazole, and "OMe" for methoxy), is modified to be ultra‐stable in aqueous conditions and possesses sulfonic acid groups for general acid catalysis and for enhanced hydrogen bonding with reactants as well as intraporous chloride anions for oxocarbenium intermediate stabilization. In addition, the system also relies on the differences in adsorptive binding behavior, Kads, of the reactants and the products to the functionalized framework and benefits from a separate physical, kinetic process to boost the catalytic cycle. Due to its stability in aqueous conditions, HCl‐PSA‐IM‐COF‐OMe can be recycled and maintains its hydrolytic properties for five cycles before regeneration is needed. [ABSTRACT FROM AUTHOR]

The Cephalomalthinus semifumatus species group, referred to as the "semifumatus" group henceforth, is interesting because of its heterogeneous morphology resembling either Cephalomalthinus Pic, 1921 or Rhagonycha Eschscholtz, 1830. To elucidate its phylogenetic status, mitochondrial genomes of four species of the "semifumatus" group, 11 Cephalomalthinus species, and 11 Rhagonycha species were sequenced and examined. All analysed mitogenomes were similar with respect to genome size, nucleotide composition, and AT content. Surprisingly, a rearrangement of the trnW‐trnC and trnY genes was detected in the "semifumatus" group, presumably caused by tandem duplication and random loss events. Furthermore, genetic distance analyses showed that the proximity of the "semifumatus" group to Cephalomalthinus and to Rhagonycha was comparable to that between the latter two. Moreover, the produced phylogeny strongly supported the monophyly of the "semifumatus" group, and molecular clock analyses dated its divergence from Cephalomalthinus to 32.52 Ma. Thus, the new genus Amphimorphusgen. nov. is suggested to comprise the "semifumatus" group, in which the observed gene rearrangement was a synapomorphy. Moreover, morphological evidence regarding the unique structure of the aedeagus supported this separation. These results indicate that mitochondrial gene rearrangement provide important phylogenetic implications for revising Cephalomalthinus, a speciose genus that is puzzling in the morphology‐based taxonomy. [ABSTRACT FROM AUTHOR]

Simple Summary: The East Palaearctic fauna of net-winged beetles is very rich, but poorly studied in China. As an important faunistic component of the East Palaearctic fauna, the detailed taxonomic studies of Lycidae from China are necessary for understanding the evolution of this important biodiversity hotspot. More importantly, it is a region where some lycid lineages occur only there and in an adjacent part of the Oriental Region, such as Mesolycus Gorham, 1883. The genus remains controversial in its systematic placements but has never been rigorously tested due to unavailability of sampling material. In the present study, the genus Mesolycus was reviewed, with an emphasis on the species diversity from the Chinese fauna. Meanwhile, multiple genetic data of this genus were obtained and included in the phylogeny of lycid beetles for the first time. As a result, it is quite surprising that the number of the Chinese Mesolycus species is increased from 6 to 13, which makes China stand out in the species diversity on a world scale. Meanwhile, the statuses of some previously known species were clarified, and the systematic placement of Mesolycus was verified. This study makes us better understand the species diversity and phylogenetic position of Mesolycus. The lycid genus Mesolycus Gorham, 1883 is mainly distributed in East Palaearctic and Indochinese regions, but poorly studied in China; moreover, its phylogenetic placement remains controversial but has never been rigorously tested. In this study, Mesolycus was reviewed and its placement within Lycidae was tested based on a multilocus phylogeny (cox1, nad5, cox2 and Lrna) by both ML and BI analyses. The reconstructed phylogenies show that Mesolycus is a consistently recovered sister to Dilophotes Waterhouse, 1879, and they form a monophyletic clade which is well supported. This suggests that Mesolycus definitely belongs to Dilophotini rather than to Macrolycini of Lycinae. Besides, three species originally described or placed in Dilophotes are transferred to Mesolycus, including M. atricollis (Pic, 1926) comb. n., M. particularis (Pic, 1928) comb. n. and M. pacholatkoi (Bic, 2002) comb. n. Four new species are discovered in China, including M. shaanxiensis sp. n., M. dentatus sp. n., M. breviplatus sp. n. and M. varus sp. n. Two species, M. murzini Kazantsev, 2004 and M. rubromarginatus Kazantsev, 2013, are recorded from China for the first time. A key for the identification of all Mesolycus species is provided. China was revealed as the region with the highest species diversity of this genus. [ABSTRACT FROM AUTHOR]

Simple Summary: The family Cleridae is a cosmopolitan group with approximately 4000 species and 320 genera. Within the family, the phylogenetic relationships among the subfamilies, and the timing of divergence, remain not yet fully resolved. Mitochondrial genomes have been widely used to reconstruct phylogenies of various insect groups, but never introduced to Cleridae until now. In this study, we newly generated 18 complete or nearly complete mitochondrial genomes, which are conserved in the organization and structure, as well as exhibit typical high A+T-bias and a preference of nucleotides A and G over T and C, as other insects. Further based on these sequences, a phylogeny of this family is reconstructed of different datasets by both maximum likelihood (ML) and Bayesian inference (BI) methods. The results are congruent and support the monophylies of the family and each subfamily, and the subfamilial relationships are recovered as Korynetinae + (Tillinae + (Clerinae + Hydnocerinae)). Moreover, a molecular clock analysis estimated the divergence time of Korynetinae from others no later than 160.18Mya (95% HPD: 158.18–162.06Mya). The current study presents the first mitochondrial genome-based phylogeny of Cleridae, which provides new evidence in reconstructing the phylogenetic relationships among the subfamilies and understanding the mitochondrial features of this family. The predaceous beetle family Cleridae includes a large and widely distributed rapid radiation, which is vital for the ecosystem. Despite its important role, a number of problems remain to be solved regarding the phylogenetic inter-relationships, the timing of divergence, and the mitochondrial biology. Mitochondrial genomes have been widely used to reconstruct phylogenies of various insect groups, but never introduced to Cleridae until now. Here, we generated 18 mitochondrial genomes to address these issues, which are all novel to the family. In addition to phylogenomic analysis, we have leveraged our new sources to study the mitochondrial biology in terms of nucleotide composition, codon usage and substitutional rate, to understand how these vital cellular components may have contributed to the divergence of the Cleridae. Our results recovered Korynetinae sister to the remaining clerids, and the calde of Clerinae+Hydnocerinae is indicated more related to Tillinae. A time-calibrated phylogeny estimated the earliest divergence time of Cleridae was soon after the origin of the family, not later than 160.18 Mya (95% HPD: 158.18–162.07 Mya) during the mid-Jurassic. This is the first mitochondrial genome-based phylogenetic study of the Cleridae that covers nearly all subfamily members, which provides an alternative evidence for reconstructing the phylogenetic relationships. [ABSTRACT FROM AUTHOR]

Simple Summary: The classification of Lampyridae has been extensively debated. Although some recent efforts have provided deeper insight into it, few genes have been analyzed for Cyphonocerinae in the molecular phylogenies, which undoubtedly influence elucidating the relationships of fireflies. In this study, we generated the first complete mitochondrial genome for Cyphonocerinae, with Cyphonocerus sanguineus klapperichi as the representative species. The comparative analyses of the mitogenomes were made between C. sanguineus klapperichi and that of well-characterized species. The results showed that the mitogenome of Cyphonocerinae was conservative in the organization and characters, compared with all other fireflies. Like most other insects, the cox1 gene was most converse, and the third codon positions of the protein-coding genes were more rate-heterogeneous than the first and second ones in the fireflies. The phylogenetic analyses suggested that Cyphonocerinae as an independent lineage was more closely related to Drilaster (Ototretinae). Nevertheless, more sampler species are needed in the reconstruction of fireflies' phylogeny to verify this result. Complete mitochondrial genomes are valuable resources for phylogenetics in insects. The Cyphonoceridae represents an important lineage of fireflies. However, no complete mitogenome is available until now. Here, the first complete mitochondrial genome from this subfamily was reported, with Cyphonocerus sanguineus klapperichi as a representative. The mitogenome of C. sanguineus klapperichi was conserved in the structure and comparable to that of others in size and A+T content. Nucleotide composition was A+T-biased, and all genes exhibited a positive AT-skew and negative GC-skew. Two types of tandem repeat sequence units were present in the control region (136 bp × 2; 171 bp × 2 + 9 bp). For reconstruction of Lampyridae's phylogeny, three different datasets were analyzed by both maximum likelihood (ML) and Bayesian inference (BI) methods. As a result, the same topology was produced by both ML analysis of 13 protein-coding genes and 2rRNA and BI analysis of 37 genes. The results indicated that Lampyridae, Lampyrinae, Luciolinae (excluding Emeia) were monophyletic, but Ototretinae was paraphyletic, of which Stenocladius was recovered as the sister taxon to all others, while Drilaster was more closely related to Cyphonocerinae; Phturinae + Emeia were included in a monophyletic clade, which comprised sister groups with Lampyridae. Vesta was deeply rooted in the Luciolinae. [ABSTRACT FROM AUTHOR]

Simple Summary: Melyridae, in a broad sense including Dasytinae and Malachiinae, is the largest family of Cleroidea distributed worldwide. However, the former two subfamilies are always treated as independent families by the European coleopterists. Opposite results have been produced by the two latest molecular phylogenetic works, so the development of reliable markers for reconstructing the phylogenetic relationships between the above taxa is of great importance. Here, we present the annotated complete mitogenome of Cordylepherus sp., which is the first complete mitogenome in Melyridae. The mitogenome of Cordylepherus sp. presents the typical organization of an insect mitochondrion. Comparisons of the newly generated mitogenome of Cordylepherus sp. to all available mitochondrial genomes of other Melyridae revealed no significant differences among them in terms of the length of each protein-coding gene, AT content of different genome regions, amino acid composition and relative synonymous codon usage. Phylogenetic analyses based on 13 protein-coding genes of mitogenomes show that the monophyly of Melyridae sensu lato is not supported, and Malachiinae and Dasytinae are suggested to be independent families, which are sister groups of Prionoceridae and Cleridae, respectively. Large-scale analyses with denser locus and taxon sampling are needed to confirm the present results. To explore the characteristics of the mitogenome of Melyridae and reveal phylogenetic relationships, the mitogenome of Cordylepherus sp. was sequenced and annotated. This is the first time a complete mitochondrial genome has been generated in this family. Consistent with previous observations of Cleroidea species, the mitogenome of Cordylepherus sp. is highly conserved in gene size, organization and codon usage, and secondary structures of tRNAs. All protein-coding genes (PCGs) initiate with the standard start codon ATN, except ND1, which starts with TTG, and terminate with the complete stop codons of TAA and TAG, or incomplete forms, TA- and T-. Most tRNAs have the typical clover-leaf structure, except trnS1 (Ser, AGN), whose dihydrouridine (DHU) arm is reduced. In the A+T-rich region, three types of tandem repeat sequence units are found, including a 115 bp sequence tandemly repeated twice, a 16 bp sequence tandemly repeated three times with a partial third repeat and a 10 bp sequence tandemly repeated seven times. Phylogenetic analyses based on 13 protein-coding genes by both Bayesian inference (BI) and maximum likelihood (ML) methods suggest that Melyridae sensu lato is polyphyletic, and Dasytinae and Malchiinae are supported as independent families. [ABSTRACT FROM AUTHOR]

In this work, by combining the superiority of polyoxometalates (POMs) and catalytic single-metal site Co of metalloporphyrin, a series of mixed-valence POM-based metal-organic frameworks (MOFs) composites is synthesized by a post-modification method. The electron-transfer property of POM@PCN-222(Co) composite is significantly enhanced owing to the directional electron-transfer from POM to single-metal site Co in PCN-222(Co). In particular, H-POM@PCN-222(Co) gives a high Faradaic efficiency of 96.2% for electroreduction of CO 2 into CO and good stability over 10 h. DFT calculations confirm that the directional electron transfer, which accelerates the multi-electron transfer from the electrode to active single-metal site Co, enriches the electron density of the Co center, and ultimately reduces the energy of the rate-determining step, thus increasing the catalytic activity of CO 2 reduction reaction (CO 2 RR). This work therefore suggests some new insight for the design of efficient electrocatalysts for CO 2 RR., (© 2021 Wiley-VCH GmbH.)

We report a correlation between the structural phase transition of CsPbX 3 (X=Cl, Br, I) nanocrystals (NCs) and their temperature dependent steady-state photoluminescence (PL) and time-resolved PL (TRPL). In constrast to CsPbBr 3 and CsPbI 3 NCs which exhibited a continuous blue shift in their bandgap with increasing temperature, the CsPbCl 3 exhibited a blue shift until ~193 K, followed by a red shift until room temperature. We attribute this change from a blue to a red shift to a structural phase transtion in CsPbCl 3 , which also manifested in the temperature dependent TRPL. Notably, the exciton recombination lifetimes showed a similar reverse trend due to the phase transition in CsPbCl 3 , which has not been reported previously., Competing Interests: Conflicts of interest The authors declare no conflict of interest.