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Scolytus unicornis, a new species of Scolytus Geoffroy from Yunnan, China, is described and illustrated. Three DNA barcoding sequences (COI, 28S, CAD) of this species are provided. The new species is distinguished from other Asian Scolytus species by the longitudinal wrinkles on the frons only in the area below the eyes, a large median spine situated in the middle of the ventrite 2 base, and female frons with a slightly raised blunt tubercle above the epistoma.

Transgenic crops producing Bacillus thuringiensis (Bt) toxins are widely planted for insect control, but their efficacy may decrease as insects evolve resistance. Understanding the genetic basis of insect resistance is essential for developing an integrated strategy of resistance management. To understand the genetic basis of resistance in pink bollworm ( Pectinophora gossypiella ) to Bt cotton in the Yangtze River Valley of China, we conducted an F2 screening for alleles associated with resistance to the Bt (Cry1Ac) protein for the first time. A total of 145 valid single-paired lines were screened, among which seven lines were found to carry resistance alleles. All field parents in those seven lines carried recessive resistance alleles at the cadherin locus, including three known alleles, r1 , r13 and r15 , and two novel alleles, r19 and r20 . The overall frequency of resistance alleles in 145 lines was 0.0241 (95% CI: 0.0106-0.0512). These results demonstrated that resistance was rare and that recessive mutation in the cadherin gene was the primary mechanism of pink bollworm resistance to Bt cotton in the Yangtze River Valley of China, which will provide a scientific basis for implementing targeted resistance management statics of pink bollworm in this region.

A new species of bark beetle, Scolytus jiulianshanensis Zhang, Li Smith sp. nov., from Jiangxi, China is described and illustrated. This new species was collected from dead elm (Ulmus sp.) trees. A DNA barcoding sequence of this species is provided. The new species is distinguished from other Asian Scolytus species by the apical margins of ventrites 3 and 4 of the male each armed with a broad median tubercle and lacking ventral spines.

Sitophilus oryzae (Coleoptera: Curculionidae) and Sitophilus zeamais (Coleoptera: Curculionidae) are major insect pests of farm-stored grains in China. Moreover, their respective distribution and prevalence are not yet assessed for grain storage facilities in China. The two species are often difficult to identify by morphology because they are immature or their presence is only evident from fragments. Species-specific primers were, therefore, designed based on the cytochrome c oxidase subunit I (COI) of 34 populations found throughout China and three foreign populations. Following the validation of this molecular-based approach for species identification, the distribution of the two species in China was determined from 68 different grain storage facilities. The results indicate that S. zeamais is prevalent throughout the country whereas S. oryzae is mainly present in the south and the center of China. It is believed that this distribution pattern is in function of ecological adaptation, mostly determined by temperature and the grain species. This is the first report of its kind, demonstrating the distribution of S. zeamais and S. oryzae in grain storage facilities throughout China and analyzed by species-specific primers of COI.

The Asian larch bark beetle, Ips subelongatus, is considered to be the major pest of larch within its natural range. We investigated the electrophysiological and behavioral characteristics as well as mitochondrial DNA cytochrome oxidase subunit I sequences of I. subelongatus from 13 geographic populations throughout northeastern China in order to explore population divergence of aggregation pheromone responses and the extent of potential genetic divergence. Electrophysiological analyses showed that antennae of I. subelongatus from all the six tested populations responded strongly to (S)-(-)-ipsenol (100% detection; 0.35-0.73 mV) in gas chromatography (GC)-electroantennographic detection (EAD) analyses, while its antipode, (R)-(+)-ipsenol was antennally inactive. I. subelongatus populations varied in their responses to (R)-(-)- and (S)-(+)-ipsdienol in GC-EAD analyses. Behavioral bioassays demonstrated that (S)-(-)-ipsenol alone was significantly attractive at all the tested sites, supporting its status as a key pheromone component of I. subelongatus, whereas (S)-(+)-ipsdienol was inactive alone. Adding (S)-(+)-ipsdienol to (S)-(-)-ipsenol did not have any effect on the trap catches from some populations in Inner Mongolia. However, (S)-(+)-ipsdienol showed a strong synergistic effect on (S)-(-)-ipsenol from several populations in Jilin and Liaoning Provinces, and a weak synergistic effect from some transition populations in Heilongjiang Province. Furthermore, 27 mitochondrial haplotypes were found among the 13 populations (intraspecific nucleotide divergence, 0.1%-1.1%). Analyses of molecular variance and haplotype networks indicated that different geographic populations have developed some genetic variation but did not form completely independent groups. From an applied point of view, a universal synthetic binary blend of racemic ipsenol and (S)-(+)-ipsdienol might have a potential for monitoring or even mass-trapping of I. subelongatus across northeastern China, even though some populations only use (S)-(-)-ipsenol alone as their active pheromone component., (© 2015 Institute of Zoology, Chinese Academy of Sciences.)

Rhinoncomimus latipes Korotyaev (Coleoptera: Curculionidae), a biological control agent of mile-a-minute weed, Persicaria perfoliata (L.) H. Gross, has been mass reared with no infusion of new genetic material for 8-9 yr (at least 24-36 generations), while insects from the same genetic stock have been subject to field conditions in North America for that same period of time. Our main objective was to compare the laboratory population with the field population (and in 1 yr with a Chinese field population) to determine whether genetic changes had occurred, especially ones that may reduce the effectiveness of the laboratory population when released in the field. The laboratory insects laid more eggs and had reduced survival compared with field weevils in several comparisons, and had reduced responsiveness to cues that induce reproductive diapause. Exposure to older plants had the greatest effect on induction of reproductive diapause in both laboratory and field weevils, with effects of daylength and temperature less pronounced. At least a portion of the laboratory weevil population overwintered successfully. Results suggest that it is not necessary to add wild-type genetic material to the rearing colony at this time.

The genus Niphadomimus Zherikhin, 1987 is taxonomically revised herein. In addition to the two recorded Nepalese species, N. nigriventris Zherikhin and N. niger Zherikhin, known only from the holotypes, two additional specimens of N. nigriventris are reported and six new species from China represented by 96 specimens are described and illustrated. These are: N. alcyone sp. n. (Sichuan), N. celaeno sp. n. (Yunnan), N. electra sp. n. (Yunnan), N. maia sp. n. (Yunnan), N. merope sp. n. (Shaanxi) and N. sterope sp. n. (Sichuan). All known Niphadomimus species are apterous inhabitants of the leaf litter in the upper Rhododendron-dominated forest zone between 2000 and 4114 m. Phylogenetic analyses using DNA barcodes of six new species and representatives of 13 other Molytinae genera with available DNA data (A.) corroborates Niphadomimus monophyly; (B.) strongly argues for the sister-group relationship between N. merope sp. n. from the Qinling Mt. Range and the rest of the species distributed in the Hengduan mountains; (C.) in two among four analyses weakly relates the genus with the East Palaearctic Leiosoma. The tribe Typoderini could not be shown as monophyletic, which may be due to insufficient signal content of the cox1 marker at the tribal level. The detected phylogeographic pattern of Niphadomimus is compared with that of similarly distributed or closely related clades. Temporal DNA analysis estimates the N. merope sp. n. split at 6-11 MY, while the diversification of the Hengduan clade dates between 5.5 MY and 3.6 MY, i.e. well before the onset of the Quaternary climate fluctuations.

The rice water weevil, Lissorhoptrus oryzophilus Kuschel, has two generations in southern Zhejiang, China. To determine oogenesis in first-generation females (summer females) and its relations to temperature, females were collected from a rice field in early and mid-July and reared on young rice plants at 28, 31 and 34 degrees C in the laboratory. Percentage of females having oocytes, number of oocytes of different stages (stage-I, from early previtellogenesis to middle vitellogenesis; stage-II, late vitellogenesis; and mature-oocyte stage), and length of ovarioles were determined every 10 d of feeding. At each temperature, oogenesis took place in over 40% of females after 20~40 d of feeding, but only 0.0~3.3 stage-I, 0.0~0.8 stage-II and 0.0~1.1 mature oocytes were observed at each observation date. Temperature had significant effect on number of stage-I oocytes but not on number of stage-II and mature oocytes in early July females; temperature had no significant effect on number of oocytes of either stage in mid-July females. Conclusively, in southern Zhejiang, summer L. oryzophilus females have great potential to become reproductive on rice, but their oogenesis activity is very low, with the overall procedures little affected by temperature.