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Simple Summary: The non-pollinating fig wasps are essential components of fig wasp communities, negatively impacting mutualism. However, this group of fig wasps has received less taxonomic attention than pollinating fig wasps. This study presents seven new non-pollinating fig wasp species associated with Ficus hirta fig trees inhabiting South China and Southeast Asia. The presence of a long ovipositor sheath characterizes this group of fig wasps. An identification key is provided to distinguish between them, and the relationships with their host fig trees are discussed. The type specimens and examined materials are deposited in the South China Botanical Garden, Chinese Academy of Sciences, China. Even though non-pollinating fig wasps are essential components in tropical and subtropical habitats, yet they are poorly described in the Oriental communities. This study presented seven new sycoryctine fig wasp species associated with Ficus hirta fig trees inhabiting South China and Southeast Asia. These new sycoryctine species belong to the genera Philotrypesis, Sycoryctes, and Sycoscapter. They can be easily distinguished by their adaptive morphologies such as face sculpture, body-color, and ovipositors. An identification key is provided to differentiate between them, and the relationships with their host fig trees are also discussed. The holotypes and paratypes are both deposited in the South China Botanical Garden, Chinese Academy of Sciences, China. [ABSTRACT FROM AUTHOR]

Endosymbionts living in plants and insects are pervasive. Ficus (Moraceae) has very special inflorescences (which we also call figs) enclosed like an urn, and such inflorescence is usually parasitized by fig wasps. Ficus breeds fig wasp larvae in its figs and adult fig wasps pollinate for Ficus, Ficus and its obligated pollinator formed fig-fig wasp mutualism. Previous studies have found that this confined environment in figs may have provided protection for fig wasps and that this has left some imprints on the genome of fig wasps during the coevolution history of figs and fig wasps. Research on the diversity of both bacteria and fungi in figs are fewer. Our study explored the diversity of endosymbionts in Ficus hirta figs. We utilized high-throughput sequencing and biological database to identify the specific microorganism in figs, then conducted microorganism communities' diversity analysis and function annotation analysis. As a result, we identified the dominant endosymbionts in figs, mainly some insect internal parasitic bacteria and fungi, plant pathogen, endophytes, and saprotroph. Then we also found bacteria in Ficus hirta figs were more diversified than fungi, and bacteria communities in female figs and functional male figs were different. These findings may give us more insight into the coevolution and interaction among endosymbiont, fig, and fig wasp. [ABSTRACT FROM AUTHOR]

• The olfactory and gustatory receptors of 25 pollinator fig wasps (Agaonidae) were compared. • ORs of fig wasps can be divided into ORco and ORx, with ORx evolving rapidly. • GRs clustered into documented groups containing sweet, bitter and CO 2 receptors. • More closely related fig wasps had more similar ORs and IR sequences. • Fig wasps of a single species from different hosts had different OR sequences. The mechanisms of chemoreception in fig wasps (Hymenoptera, Agaonidae) are of primary importance in their co-evolutionary relationship with the fig trees they pollinate. We used transcriptome sequences of 25 fig wasps in six genera that allowed a comparative approach to the evolution of key molecular components of fig wasp chemoreception: their odorant (OR) and gustatory (GR) receptor genes. In total, we identified 311 ORs and 47 GRs, with each species recording from 5 to 30 OR genes and 1–4 GR genes. 304 OR genes clustered into 18 orthologous groups known to be sensitive to cuticular hydrocarbons (CHC), pheromones, acids, alcohols and a variety of floral scents such as cineole, Linalool, and Heptanone. 45 GR genes clustered into 4 orthologous groups that contain sweet, bitter, CO 2 and undocumented receptors. Gene sequences in most orthologous groups varied greatly among species, except for ORco (60.0% conserved) and sweet receptors (30.7% conserved). Strong purifying selection of both odorant and gustatory genes was detected, as shown by low ω values. Signatures of positive selection were detected in loci from both OR and GR orthologous groups. Fig wasps have relatively few olfactory and especially gustatory receptors, reflecting the natural history of the system. Amino acid sequences nonetheless vary significantly between species and are consistent with the phylogenetic relationships among fig wasps. The differences in ORs within some orthologous groups from the same species, but different hosts and from closely related species from one host can reach as low as 49.3% and 9.8% respectively, implying the ORs of fig wasps can evolve rapidly to novel ecological environments. Our results provide a starting point for understanding the molecular basis of the chemosensory systems of fig wasps. [ABSTRACT FROM AUTHOR]

Inroduction: Volatile organic compounds (VOCs) emitted by the receptive syconia of Ficus species is a key trait to attract their obligate pollinating fig wasps. Ficus hirta Vahl is a dioecious shrub, which is pollinated by a highly specialized symbiotic pollinator in southern China. Terpenoids are the main components of VOCs in F. hirta and play ecological roles in pollinator attraction, allelopathy, and plant defense. However, it remains unclear that what molecular mechanism difference in terpenoid synthesis pathways between pre-receptive stage (A-phase) and receptive stage (B-phase) of F. hirta syconia., Methods: Transcriptome, proteome and Gas Chromatography-Mass Spectrometer (GC-MS) were applied here to analyze these difference., Results and Discussion: Compared to A-phase syconia, the genes ( ACAT2 , HMGR3 , GGPS2 , HDR , GPS2 , TPS2 , TPS4 , TPS10-4 , TPS14 ) related to the terpenoid synthesis pathway had higher expression level in receptive syconia (B-phase) according to transcriptome sequencing. Seven differentially expressed transcription factors were screened, namely bHLH7 , MYB1R1 , PRE6 , AIL1 , RF2b , ANT , VRN1 . Specifically, bHLH7 was only specifically expressed in B-phase. 235 differentially expressed proteins (DEPs) were mainly located in the cytoplasm and chloroplasts. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the DEPs were mainly enriched in the metabolic process. A total of 9 terpenoid synthesis proteins were identified in the proteome. Among them, 4 proteins in methylerythritol phosphate (MEP) pathway were all down-regulated. Results suggested the synthesis of terpenoids precursors in B-phase bracts were mainly accomplished through the mevalonic acid (MVA) pathway in cytoplasm. Correlation analysis between the transcriptome and proteome, we detected a total of 1082 transcripts/proteins, three of which are related to stress. From the VOCs analysis, the average percent of monoterpenoids emitted by A-phase and B-phase syconia were 8.29% and 37.08%, while those of sesquiterpenes were 88.43% and 55.02% respectively. Monoterpenes (camphene, myrcene, camphor, menthol) were only detected in VOCs of B-phase syconia. To attract pollinators, B-phase syconia of F. hirta need more monoterpenoids and less sesquiterpenes. We speculate that transcription factor bHLH7 may regulate the terpenoid synthesis pathway between A- and B-phase syconia. Our research provided the first global analysis of mechanism differences of terpenoid synthesis pathways between A and B phases in F. hirta syconia., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Fan, Jia, Wang, Chen, Liu and Yu.)