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Estimating parasitism rates in the field is essential for developing and evaluating biocontrol strategies using parasitoids. In this study, we developed a simple polymerase chain reaction (PCR)‐based method for detecting parasitism of the cassava mealybug Phenacoccus manihoti Matile‐Ferrero (Hemiptera: Pseudococcidae) by the primary parasitoid Anagyrus lopezi De Santis (Hymenoptera: Encyrtidae) and its hyperparasitoid Prochiloneurus pulchellus Silvestri (Hymenoptera: Encyrtidae). Primers were designed to amplify partial cytochrome c oxidase subunit I genes of each species, and their sensitivity was evaluated with mealybugs that had been parasitized by A. lopezi 0, 3, and 6 days earlier, and mummified mealybugs containing A. lopezi pupae that had been parasitized by P. pulchellus 0, 3, 6, 9, and 12 days earlier. The detection rate of parasitism by A. lopezi was 100% for all ages of A. lopezi. The detection rate of parasitism by P. pulchellus ranged from 94.1% to 100%, depending on its developmental stage. For P. pulchellus, template DNA was diluted 10 times before PCR because PCR with the original concentration showed low detection rates, presumably due to the presence of PCR inhibitors. Overall, our primers can be considered sufficiently sensitive to be used for detecting each species. [ABSTRACT FROM AUTHOR]

Intracellular bacteria that are mainly transmitted maternally affect their arthropod hosts' biology in various ways. One such effect is known as cytoplasmic incompatibility (CI), and three bacterial species are known to induce CI: Wolbachia, Cardinium hertigii, and a recently found alphaproteobacterial symbiont. To clarify the taxonomic status and provide the foundation for future studies to reveal CI mechanisms and other phenotypes, we investigated genetic and morphological properties of the third CI inducer that we have previously reported inducing CI in the coconut beetle Brontispa longissima. The draft genome of the bacteria was obtained from the oocytes of two isofemale lines of B. longissima infected with the bacteria: one from Japan (GL2) and the other from Vietnam (L5). Genome features of the symbionts (sGL2 and sL5) were highly similar, showing 1.3 Mb in size, 32.1% GC content, and 99.83% average nucleotide sequence. A phylogenetic study based on 43 universal and single-copy phylogenetic marker genes indicates that they formed a distinct clade in the family Anaplasmataceae. 16S rRNA gene sequences indicate that they are different from the closest known relatives, at least at the genus level. Therefore, we propose a new genus and species, "Candidatus Mesenet longicola", for the symbionts of B. longissima. Morphological analyses showed that Ca. M. longicola is an intracellular bacterium that is ellipsoidal to rod-shaped and 0.94 ± 0.26 μm (mean ± SD) in length, and accumulated in the anterior part of the oocyte. Candidates for the Ca. M. longicola genes responsible for CI induction are also described. [ABSTRACT FROM AUTHOR]

• The egg parasitoid P. saccharalis has the potential to control M. cribraria. • On the first day of emergence, starved wasps oviposited more activity than fed ones. • Fitness (r m) did not differ between starved and fed female wasps. • They altered oviposition behavior to maximize their fitness when food is lacking. Life history theory predicts that animals should increase their current reproductive effort as the probability of survival to the next reproductive opportunity decreases. We studied the effects of food depletion on life history and oviposition behavior in the egg parasitoid Paratelenomus saccharalis (Hymenoptera: Platygastridae) to determine if the parasitoid alters its reproductive strategy based on life expectancy. We first examined survivorship and reproductive effort of females provided only with water (i.e. starved) and females fed honey. Fed females lived up to 40 days, whereas starved females lived only up to 4 days. Fed females produced more offspring during life and had a higher net reproductive rate, i.e. R 0 , compared to starved females. Starved females did produce more offspring on the first day of emergence, however, and the intrinsic rate of natural increase, i.e. r m , did not differ between honey-fed and starved females. We further observed oviposition behavior in response to food availability during 24 h on the first day of emergence to determine the mechanism by which starved females increased reproductive output. Results showed that starved females oviposited more frequently than honey-fed females, and that the time required for a single oviposition was shorter for starved females. These results revealed that starved females had higher oviposition rates on the first day of emergence, leading to the similar r m of starved and fed females. This indicates that P. saccharalis altered their oviposition behavior to maximize their fitness under food-depleted conditions. [ABSTRACT FROM AUTHOR]

The kudzu bug, Megacopta cribraria (Fabricius), is native to Asia but recently invaded the US and is expanding its distribution rapidly. To assess the probability of this bug traveling by attaching to the exteriors of fast-moving vehicles, we investigated the ability of M. cribraria adults to cling to stages with different surfaces (cloth, metal, or glass) against extreme airflows in a transparent acrylic tube connected to a vacuum cleaner. On the stages with cloth and metal, insects remained on the stages at 100 km/h wind speed. Estimated wind velocities required to blow 50 % of insects from the stages within 1 min were more than 100 km/h (cloth); 60 km/h (metal); and 40 km/h (glass) for males and 100 km/h (cloth); 50 km/h (metal); and 30 km/h (glass) for females. Together with frequent observations of attached M. cribraria on vehicle exteriors in the field, our results indicate a fairly high probability of range expansion of this species by attachment to vehicles. [ABSTRACT FROM AUTHOR]

The coconut hispine beetle Brontispa longissima ( Gestro) supposedly originated in Indonesia and Papua New Guinea. It is a serious invasive pest of the coconut palm Cocos nucifera L. in Southeast and East Asia. In Japan, it has established itself using Satakentia liukiuensis ( Hatushima) H. E. Moore as a main host on Ishigaki and Iriomote Islands where C. nucifera is rare. To assess the probability of further establishment of B. longissima in novel habitats where C. nucifera and S. liukiuensis are not available, we examined the suitability of four common palm species in Japan for oviposition and immature development of B. longissima: Chrysalidocarpus lutescens ( Bory) H. Wendl., Phoenix roebelenii O' Brien, S. liukiuensis and Washingtonia filifera ( Linden ex André) H. Wendl. When seedlings of the four palm species were placed in pots in an experimental field on Ishigaki Island, all four species were inhabited and infested by wild B. longissima adults. Oviposition and immature development were observed on P. roebelenii and S. liukiuensis but not on C. lutescens and W. filifera. When field-collected adults were released into mesh bags enclosing the potted seedlings, they oviposited on all four species. The eggs developed into adults on P. roebelenii, S. liukiuensis and W. filifera. On C. lutescens, however, hatched larvae died during the first or second instar. [ABSTRACT FROM AUTHOR]

Brontispa longissima is a serious pest of the coconut palm Cocos nucifera, presumed to have originated in Papua New Guinea and Indonesia. It recently invaded Southeast and East Asia, where outbreaks have been reported. Mitochondrial DNA analysis reveals two cryptic species in B. longissima: one is distributed over a wide area including Asia and the Pacific region (the Asian clade) and the other in a limited area in the Pacific region (the Pacific clade). Recent invasions and outbreaks have been reported only from the area where the Asian clade has been found, suggesting that this clade has become a pest in Asia. To infer if the Asian clade has the ability to establish, spread and outbreak in novel habitats more effectively than the Pacific clade, we compared life-history traits between the two populations of different clades. The net reproduction rate ( R0) was 130.0 and 94.0, the mean length of a generation ( T) was 57.7 and 54.7 days, and the intrinsic rate of natural increase ( r) was 0.084 and 0.083 per day for the population from Ishigaki Island, Japan ( ISH) (the Asian clade) and for the population from Papua New Guinea ( PNG) (the Pacific clade), respectively. Although the difference in r was little, the simulated population growth showed that the ISH population can be 1.6 times larger than that of the PNG after ten generations. The rapid population growth of the Asian clade would be partly responsible for its establishment, spread and frequent outbreaks in Asia. [ABSTRACT FROM AUTHOR]

Brontispa longissima (Coleoptera: Chrysomelidae) is a serious invasive pest of coconut palm ( Cocos nucifera) supposedly originating from Indonesia and New Guinea. It has recently invaded Southeast and East Asia, where it has caused serious damage to coconut plants. Brontispa longissima as currently defined contains two cryptic species: we herein referred to one as the 'Asian clade', which is distributed over a wide area, including Asia and the Pacific region; and we referred to the other one as the 'Pacific clade', which is found in a limited area in the Pacific region. We developed a PCR-RFLP method for differentiating the two clades. Digestion of the PCR product of a 1,014-bp region within the mitochondrial cytochrome oxidase I gene ( COI) with BslI, HpyCH4III, or NlaIV resulted in clade-specific patterns as estimated by the sequence data. We applied the method to specimens newly obtained from various locations to investigate the geographical distribution of B. longissima. Although B. longissima collected from Samoa in April 2003 had been placed in the Pacific clade, specimens collected from the same island in April 2010 were placed in the Asian clade, suggesting that the predominant clade may have been changing from the former to the latter. On Timor, specimens included both clades in apparently segregated habitats. [ABSTRACT FROM AUTHOR]

The coconut hispine beetle Brontispa longissima has been causing serious damage to the coconut palm Cocos nucifera in the Pacific, and Southeast and East Asia. This beetle also attacks Satakentia liukiuensis, an endemic palm on Ishigaki and Iriomote Islands, Japan. To assess the potential impact of B. longissima on S. liukiuensis, we examined the development period, survival rate, egg production and body size of B. longissima on S. liukiuensis at 22-31°C and consumption of S. liukiuensis leaf at 28°C. We also examined these life history traits on C. nucifera at 28°C to compare with those on S. liukiuensis. Brontispa longissima completed their development and reproduced on S. liukiuensis at 22-30°C. Linear regression analysis was used to estimate the effective cumulative temperature ( k) as 891.2 degree-days, and the lower developmental threshold as 13.3°C. On the basis of these values and monthly average temperatures on Ishigaki Island, it was estimated that B. longissima has four generations per year on the island. Satakentia liukiuensis was less suitable for B. longissima than C. nucifera in terms of immature survival, development time, resultant adult size and reproduction. The low quality of S. liukiuensis as a host-plant may prevent the outbreak of B. longissima, which has not occurred yet on Ishigaki and Iriomote Islands. [ABSTRACT FROM AUTHOR]

The beetle Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae) is a serious invasive pest of the coconut palm, Cocos nucifera L., in Southeast Asia and the Pacific region. Genetic analysis is essential to ecological and evolutionary study of such invasive species. We therefore conducted molecular analyses by using partial sequences (1044 bp) of the mitochondrial cytochrome oxidase subunit I (COI) genes of B. longissima collected from several locations. We found two monophyletic groups: one distributed over a limited area (Australia, Papua New Guinea, Samoa, and Sumba Island; referred to as the Pacific group) and the other collected from a wide area of Asia and the Pacific region (referred to as the Asian group). We compared the biological and morphological traits of the two groups. We found that insects in the Pacific group had a shorter developmental time from hatching to adult emergence, produced fewer eggs, and had a larger adult body size than insects in the Asian group. Elytral color patterns did not differ between the two groups. Our interpopulation crosses produced significantly fewer progeny than intrapopulation crosses, suggesting that B. longissima represents two cryptic species. [ABSTRACT FROM AUTHOR]

We conducted field experiments to examine flight orientation behavior of Ooencyrtus nezarae Ishii, an egg parasitoid of soybean feeding bugs, using sticky traps with synthetic aggregation pheromones of the host, Riptortus clavatus (Thunberg). Experiments were conducted in plots either containing a soybean field or not containing one. When the traps were suspended at heights of 0.5, 1.5 and 3.0 m above a soybean field in Kobe, O. nezarae females were most frequently caught in the 0.5 m traps. In an open field on the same campus where the vegetation was predominantly tall goldenrod, females were more frequently trapped at 1.5 or 3.0 m. In a soybean field in Kumamoto, females were most frequently trapped in the 0.8 m traps, compared to traps placed at 2.0, 4.0 and 6.0 m. In an oat field in the same area, females were trapped most frequently at heights of 0.8 and 2.0 m. Unlike females, only a small number of males were trapped in the fields in both areas. The result that O. nezarae females were caught in traps at higher positions in non-host habitats than in soybean fields probably reflects differences in host searching behavior in or movement between the habitats. In host habitats, females mainly walk on the plants or fly within the plant canopy to search for hosts. In non-host habitats, females may not intensively search for hosts within the plants, and directly respond to host pheromones in the traps at heights equal to or a little higher than the plant canopy. [ABSTRACT FROM AUTHOR]

Pupal parasitoids are considered to be idiobionts. However, some pupal parasitoids do not seem to kill or paralyze hosts at oviposition, including Tetrastichus brontispae , an endo-pupal parasitoid of Brontispa longissima. We conducted laboratory experiments to determine if T. brontispae parasitizes pupal hosts with a koinobiont developmental strategy. For this to be the case, its immatures would have to develop during the host transition from pupa to adult and in adulthood. With 0-d-old to 5-d-old pupal hosts, the T. brontispae females stung hosts of all ages with over 80% frequency. When the pupal hosts were parasitized, there were two modes of parasitism: pupal parasitism and pupal-adult parasitism. For pupal hosts that were parasitized, the majority showed a typical pupal parasitism, involving first the mummification of parasitized pupae and then the development of the parasitoid immatures within and emergence from these mummified pupae. However, the parasitized pupae that did not become mummified developed to host adults in which the parasitoid immatures developed, indicating pupal-adult parasitism. When parasitized pupal hosts were mummified, the 0-d-old to 3-d-old pupae were more likely than the older pupae to be mummified and had a greater number of parasitoid adults produced per host. The pupal-adult parasitism was not as successful. The parasitoid adults only successfully emerged from two host adults, which were parasitized as 2-d-old pupae, and one host adult parasitized as a 3-d-old pupa. The parasitoid eggs laid in 4-d-old and 5-d-old pupae continued to develop during and after the host transition from the pupa to adult. However, when the host adults died within 10 days after emergence, all the parasitoids died without completing their development. These results suggest that T. brontispae is a koinobiont parasitoid that successfully parasitizes young pupal hosts mainly through host mummification and rarely through pupal-adult parasitism. The fact that many parasitized 4-d-old or 5-d-old pupae died at the pupal or adult stage without producing any parasitoids, may also suggest that, under natural conditions, the pupal and adult mortality of B. longissima resulting from parasitism by T. brontispae is significant. [ABSTRACT FROM AUTHOR]

To clarify the reproductive properties of the coconut pahn pest, Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae), we investigated in the laboratory the diel periodicity in copulation, effect of adult age after emergence on copulation and ovarian development, reproductive development in relation to female age, and the possibility of multiple mating. The beetles used in this study were reared in the laboratory and were fed an alternative food plant, narrowleaf cattail, Typha domingensis Pers. (Typhaceae). Copulation occurred throughout the 24-h cycle but mostly occurred in the photophase with two peaks, one at the onset of lights-on and the other 8-12 h after lights-on, indicating that most copulation activity in B. longissima in the field occurs in the early morning and the afternoon. Females could copulate immediately after emergence, whereas males began copulating 3 wk after emergence. Ovaries of females started to develop in the absence of mating and were correlated with adult age. Mature males could copulate with females regardless of ovarian developmental stage, and females with undeveloped ovaries accepted copulation attempts. Our study showed that the tinting of copulation during the preoviposition period would not affect numbers of eggs laid, length of preoviposition period, or viability of eggs. B. longissima adults engaged in multiple mating. [ABSTRACT FROM AUTHOR]