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To better understand the semiochemical detection and reception mechanisms that involved in intra- and interspecific communication, host selection and mating behavior of Echinothrips americanus (Thysanoptera: Thripidae), scanning electron microscopy was used to examine the external morphology, distribution and ultrastructure of the sensilla on antennae and mouthparts. According to serial SEM images, seven types of antennal sensilla in total were observed in both sexes. Sensilla on mouthparts were observed concentrating on the maxillary palps, labial palps, and paraglossa, which is consistent with the previous conclusions. Possible function of the external sensilla is also discussed.

Three new genera and species of Cenomanian Cixiidae from Kachin amber (Myanmar) are described: Acrotiara Bourgoin & Luo gen. nov., type species A. multigranulata Luo & Bourgoin sp. nov., Delphitiara Bourgoin & Luo gen. nov., type species D. tibiocoronata Luo & Bourgoin sp. nov., and Pentacarinus Bourgoin & Luo gen. nov., type species P. kachinensis Luo & Bourgoin sp. nov. A key to identification of these new genera is provided. These cixiids with a pentacarinated mesonotum belong to a new tribe Acrotiarini Bourgoin & Luo trib. nov., type genus Acrotiara gen. nov., which is characterized by a specific set of characters, some being unique in the family Cixiidae such as the paired sublaterofrontal carinae and the arched RA on the tegmina. This new taxon prompts discussion of the current classification and phylogeny of the family, which remains widely unexplored, and of the evaluation of the placement of two older cixiid fossils currently known, Karebodopoides aptianus (Fennah, 1987) and Cixius petrinus Fennah, 1961. A new genus, Barremixius Bourgoin & Szwedo gen. nov., is proposed for the latter, resulting in the new combination Barremixius petrinus (Fennah, 1987). Karebodopoides Szwedo, 2001 and Barremixius gen. nov. are provisionally recognized as the oldest Cixiidae, respectively representative of the oecleinian lineage (including Bothriocerini trib. stat. nov.) and of the cixiinian lineage. Acrotiarini trib. nov. belongs to the pentastirinian lineage (including Borysthenini stat. nov.). All these fossils depict that the first main division that occurred in Cixiidae, occurred much earlier during the Cretaceous

Anaphothrips obscurus is a cosmopolitan pest feeding on cereals and other grasses. The effects of constant temperatures on the biology of A. obscurus are not well known. Laboratory studies were conducted to assess the effects of temperature on the development, survival, longevity, fecundity and population parameter of A. obscurus at six constant temperatures (15, 20, 25, 30, 32, 35 °C). The hatchability was the lowest at 15 °C, the highest at 25 °C and no eggs hatched at 35 °C. Developmental rates increased linearly as the temperature increased. The lower developmental threshold temperature was 10.6 °C and 200 degree-days were required to complete development from egg to adult. Adult longevity decreased with increasing temperature, and ranged from 68.87 d at 15 °C to 16.41 d at 32 °C. The highest total fecundity occurred at 20 °C with 162 eggs per female. The temperature-dependent total fecundity, age-specific oviposition rate, and age-specific survival rate models were described. The intrinsic rate of increase (rm) was significantly higher at 30 and 32 °C (0.239 and 0.250) than at other temperatures. This study suggests that optimal developmental and reproductive temperatures for A. obscurus ranges between 25 and 30 °C and this may help this species adapt to warmer areas and widen its distribution and potential for damage in response to global warming. These findings will also be useful in developing monitoring programs, population dynamic models, and timing of control measures for A. obscurus.

The morphology and ultrastructure of the compound eye of the predatory bug, Montandoniola moraguesi (Puton, 1986) was investigated using scanning and transmission electron microscopy. Its compound eyes, which contain ∼195 ommatidia per eye, have the following characteristics: each ommatidium possesses a laminated corneal lens measuring ∼9 μm in diameter and ∼7 μm in thickness, a tetrapartite eucone crystalline cone, which is approximately 5.5 μm long, like a dumbbell with the distal end larger than the proximal end, eight clustered retinula cells ∼25.6 μm in length, two primary pigment cells and eight secondary primary pigment cells. The rhabdomeres of the eight retinula cells form a circular, tiered rhabdom of two elongated and six peripheral retinula cells. The rhabdomeres of cells R7 and R8 are distributed along the basolateral surface of the cone and form a centrally-fused rhabdom that spans nearly the full length of the ommatidium. The microvilli of the peripheral rhabdom (R1–R6) are radially arranged and form a bilobed, V-like shape in the central rhabdom. Based on the similarity of the compound eye of M. moraguesi to the eyes of other predatory insect species, the evolution and function of eyes in predators are briefly discussed.

Anaphothrips obscurus (Muller) is a cosmopolitan pest feeding on cereal crops and grasses. This species exhibits wing polyphenism. Differences in the life history traits of female macropterous and brachypterous A. obscurus were compared in the laboratory for this study. Experiments were performed in climate chambers set at 20 and 25 ± 1 °C, 60 ± 10% RH under a 16 L:8D photoperiod. The duration of total pre-adult stage, adult pre-oviposition period and total pre-oviposition period of macropterous morphs were significantly longer than in the brachypterous morphs both at 20 and 25 °C. No significant differences were found in adult longevity, survival rate or total fecundity between the two wing morphs, while early fecundity was significantly higher for brachypterous females compared with that for macropterous females at two temperatures.

Three pheromone-binding proteins of Helicoverpa armigera were cloned and expressed in Escherichia coli. In order to characterize their physiological properties, ligand-binding experiments were performed using five biologically relevant substances including sex pheromones and interspecific signals. The results showed that one of the pheromone-binding proteins, HarmPBP1, binds strongly to each of the two principal pheromone components of H. armigera, (Z)-11-tetradecenal and (Z)-9-hexadecenal, but not to the interspecific signal (Z)-9-tetracecenal. The two remaining pheromone-binding proteins, HarmPBP2 and HarmPBP3, showed only weak affinities with the ligands tested. The 3-D structure of HarmPBP1 was predicted and the docking experiments indicate that the key binding site of (Z)-9-hexadecenal to HarmPBP1 includes Thr112, Lys111, and Phe119 whereas that of (Z)-11-tetradecenal includes Ser9, Trp37, Phe36, and Phe119.