Comprehensive DNA barcode reference library and optimization of genetic divergence threshold facilitate the exploration of species diversity of green lacewings (Neuroptera: Chrysopidae)

Chrysopidae are a family of Neuroptera of significant importance in biocontrol against agricultural pests because of their predatory larvae. Currently, the taxonomy of Chrysopidae lacks a comprehensive revision, which impedes the exploration of species diversity as well as the selection and the conservation of green lacewings as biocontrol agents. We have established a DNA barcode reference library of the Chinese green lacewings based on an approximately complete sampling (95.63%) in 25 of the 34 provincial regions in China, comprising 1 119 barcodes of 25 genera and 197 species (representing 85% genera and 43.62% species from China). Combining other 1 049 high quality green lacewing DNA barcodes, we first inferred the optimal threshold of interspecific genetic divergence (1.87%) for successful species identification in multiple simulated scenarios based on present data. We further inferred the threshold of genetic divergence (7.77%) among genera with biocontrol significance. The inference and performance of the threshold appears to be mainly associated with the completeness of sampling, the proportion of closely related species, and the analytical approaches. Six new combinations, Apertochrysa platypa (Yang & Yang, 1991) comb. nov., Apertochrysa shennongana (Yang & Wang, 1990) comb. nov., Apertochrysa pictifacialis (Yang, 1988) comb. nov., Apertochrysa helana (Yang, 1993) comb. nov., Plesiochrysa rosulata (Yang & Yang, 2002) comb. nov., and Signochrysa hainana (Yang & Yang, 1991), are proposed according to integrative species delimitation. Our library and optimal threshold will effectively facilitate the exploration of species diversity of green lacewings. Our study also provides a methodological reference in molecular delimitation of other insects.

New Mitogenomes of the Green Lacewing Tribe Ankylopterygini (Neuroptera: Chrysopidae: Chrysopinae) and Phylogenetic Implications of Chrysopidae

Chrysopidae (green lacewings) are a cosmopolitan and species-rich family of Neuroptera, with remarkable significance of biological control against various agricultural and forestry pests. However, the phylogenetic position of Chrysopidae in Neuroptera and the internal relationships within the family remain equivocal among previous studies based on different types of data and sampling. Here we sequenced the mitochondrial genomes (mitogenomes) of two species of the genus Ankylopteryx in the chrysopine tribe Ankylopterygini for the first time. The characteristics of these mitogenomes were analyzed in comparison with other green lacewing mitogenomes published to date. In the phylogeny herein reconstructed based on mitogenomes, Chrysopinae were recovered as the sister group to Apochrysinae + Nothochrysinae. Within the subfamily of Chrysopinae, Nothancylini were recovered as the sister group to (Leucochrysini + Belonopterygini) + (Ankylopterygini + Chrysopini). The divergence time estimation suggested an Early Cretaceous initial divergence within the extant Chrysopidae. Within Chrysopinae, the four tribes except Nothancylini diverged around mid-Cretaceous.

Discovery and redescription of the true Nuvolumbrosus Navás and naming of a new Nuvol species (Neuroptera, Chrysopidae, Leucochrysini)

Examination of a newly discovered specimen of Nuvol showed that our earlier species determination of Nuvolumbrosus Navás had been incorrect and that our "redescription" of the species actually applied to an undescribed species. Here, we redescribe the true N.umbrosus, based on a newly discovered male specimen. This specimen closely resembles Navás' description, and it was collected from the Atlantic Forest as was the original type specimen. In addition, we assign the previously misidentified Nuvol specimens from the Amazonian region to a separate species, Nuvolsatur Sosa & Tauber, sp. nov. As a result of these actions, the genus Nuvol now contains two morphologically and geographically distinct species. In addition, the abdomens and genitalia of both sexes of Nuvol are now described (although each from a separate species).

The green lacewing genus Anachrysa Hölzel, 1973 (Neuroptera, Chrysopidae): a new species, two new combinations, and updated key to species

A new species, Anachrysaadamsi sp. nov., from Yunnan, China is described. Two new combinations are proposed, namely Anachrysaalviolata (Yang & Yang, 1990), comb. nov. and Anachrysatriangularis (Yang & Wang, 1994), comb. nov. An updated key to species is also provided.

Notes on the green lacewing subgenus Chrysopidia (s. str.) Navás, 1910 (Neuroptera, Chrysopidae), with description of a new species from China

A taxonomic study of the green lacewing subgenus Chrysopidia (s. str.) from China is presented. Based on the examination of type specimens of the genus reported by previous Chinese scholars and the line drawings of Chrysopidiamanipurensis provided by Ghosh (1990), I proposed five new combinations: Apertochrysaplatypa (Yang & Yang, 1990), comb. nov., Apertochrysayangi (Yang, 1997), comb. nov., Apertochrysashennongana (Yang & Wang, 1990), comb. nov., Apertochrysazhaoi (Yang & Wang, 1990), comb. nov., and Apertochrysamanipurensis (Ghosh, 1990), comb. nov. As for Chrysopidiasinica Yang & Wang, 1990, I still treat it as a valid species until supplementary specimens are available because the gonarcal complex of the type specimen is missing. A new species Chrysopidia (Chrysopidia) tjederisp. nov. is also described based on new materials. A key to all known species of this subgenus is also provided.