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A new species of tiphiid wasp, namely, Tiphia (Tiphia) andhraensis Hanima & Girish Kumar sp. nov. is described from Andhra Pradesh in the southern coastal region of India based on the female holotype. The new species is described, illustrated and compared with congeneric species. The diagnostic character of the new species is the presence of a strong, median longitudinal carina on posterior side of propodeum. The new species described here was collected from the Mudasarlova reservoir area of the Visakhapatnam district of Andhra Pradesh. The previous key to the species of Tiphia from the Indian subcontinent is modified to accommodate the new species. This new species is the first tiphiid wasp described from Andhra Pradesh. [ABSTRACT FROM AUTHOR]

The tiphiid wasp fauna of Madagascar consists of 28 endemic species, including 12 species of Anthobosca (Anthoboscinae), nine species of Methocha (Methochinae), two species of Tiphia (Tiphiinae) and in the Myzininae three species of Meria, eight species of Mesa and two species of Myzinella. Seven species of Methocha, arcuata, depressa, flavipalpus, impunctata, nasiformis, robusta and strigosa, and one species of Myzinella, minima, are described as new. All of the genera are shared with mainland Africa.

Tiphia vernalis Rohwer and Tiphia popilliavora Rohwer are ectoparasitoids of root-feeding larvae of the Japanese beetle, Popillia japonica Newman, and oriental beetles, Anomala orientalis Waterhouse (Coleoptera: Scarabaeidae). Little is known about the influence of host species and location in the host detection ability of tiphiid wasps. In this study, we examined the response of female T. popilliavora wasps, an understudied Tiphia species, to potential host stimuli using dual choice tests in an observation chamber filled with soil. T. popilliavora wasps were able to successfully discriminate the trails containing body odor or frass of P. japonica grubs fromtrails without cues. Frass trails of P. japonica grubs elicited stronger responses than body odor trails. We also examined the preference of host cues by tiphiid wasps using dual choice behavioral assays. Both T. vernalis and T. popilliavora wasps did not show preference toward trails that either contained P. japonica or A. orientalis cues. In addition, we also determined the detection of host cues by tiphiid wasps in a dual-choice test for cues presented at varying soil depths. Wasps were able to successfully discriminate between the Y-tube arms with and without cues when the cues of P. japonica were buried at a depth of 2 cm. In contrast, both Tiphia species were unable to distinguish between the Y-tube arms with and without cues when the cues were buried at a depth of 5 cm. Thus, our findings suggest that once Tiphia wasps land on the ground, they can detect the presence of their specific hosts, just below the soil surface by exploiting the kairomones present in grub body odor trails and frass and once the wasps are in the soil, they use the same cues to direct themselves to the host grubs. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examine how tiphiid wasps handle Japanese and oriental beetle grubs. [•] We examine the defensive behaviors of scarab grubs. [•] Tiphia vernalis spent longer time trying to sting oriental beetles. [•] Oriental beetles spent longer time on defensive behaviors. [•] Oriental beetle grubs are less susceptible to T. vernalis attack. [ABSTRACT FROM AUTHOR]

Japanese beetle, Popillia japonica Newman, and oriental beetle, Anomala orientalis (Waterhouse) (both Coleoptera: Scarabaeidae) are considered invasive species and have been reported as key pests of urban landscapes in the Northeastern USA. Tiphia vernalis Rohwer and Tiphia popilliavora Rohwer ( Hymenoptera: Tiphiidae) were introduced as biocontrol agents against these beetles. These parasitic wasps burrow into the soil and search for grubs. When a host is found, the wasp attaches an egg in a location that is specific for the wasp species. It is unknown if these wasps can detect patches of concealed hosts from a distance above ground and what role, if any, herbivore-induced plant volatiles play in their host location. This study evaluated the responses of female T. vernalis and T. popilliavora to grub-infested and healthy plants in Y-tube olfactometer bioassays. Also the effect of root herbivory on the composition of turfgrass ( Poaceae) volatile profiles was investigated by collecting volatiles from healthy and grub-infested grasses. Tiphia wasps were highly attracted to volatiles emitted by grub-infested tall fescue ( Festuca arundinacea Schreb.) and Kentucky bluegrass ( Poa pratensis L.) over healthy grasses. In contrast, wasps did not exhibit a significant preference for grub-infested perennial ryegrass ( Lolium perenne L.) as compared with the control plants. The terpene levels emitted by grub-infested Kentucky bluegrass and tall fescue were greater than that of control plants. Low levels of terpenes were observed for both test and control perennial ryegrass. The elevated levels of terpenes emitted by grub-infested Kentucky bluegrass and tall fescue coincided with the attractiveness to the tiphiid wasps. Here, we provide evidence that plant exposure to root-feeding insects P. japonica and A. orientalis resulted in an increase in terpenoid levels in turfgrasses, which strongly attracts their above-ground parasitoids. [ABSTRACT FROM AUTHOR]

Tiphia vernalis Rohwer is a hymenopteran ectoparasitoid of Japanese beetle, Popillia japonica Newman, larvae. The adult wasps feed on nectar or honeydew between mid-April and late June. Adults may contact pesticides when landing on foliage or when females hunt for grubs in the soil. The lethal effect of nursery, tuff, and landscape pesticides was determined by exposing wasps to treated foliage in the laboratory. Pesticides tested at labeled rates were the insecticides bifenthrin, carbaryl, chlorpyrifos, halofenozide, and imidacloprid; the herbicides oryzalin, pendimethalin, and a combination product with 2,4-D, dicamba, and mecoprop (multiherbicide); and the fungicides chlorothalonil and thiophanate-methyl. During 2001 and 2002, male and female T. vernalis were exposed to pesticides by using turf cores. For both years, bifenthrin, chlorpyrifos, and imidacloprid treatments lowered adult survival relative to the control, but halofenozide had minimal effect on mortality of males and females. More males than females died after exposure to carbaryl treatments. Survival of females was not reduced by exposure to herbicides or fungicides. Females were apparently more tolerant of pesticides than males. Mortality of males in response to herbicides and fungicides was more variable than for females; in 2002 trials, male mortality was higher after exposure to multiherbicide, oryzalin, pendimethalin, and thiophanate-methyl than the control. The fungicide chlorothalonil did not increase mortality of males or females in either year. Sublethal effects were not evaluated. The study indicates the choice of pesticide may be important for conserving T. vernalis in nursery, landscape, and turf settings. [ABSTRACT FROM AUTHOR]

The effect of insecticides on oviposition of Tiphia vernalis Rohwer and subsequent survival of parasitoid progeny to the cocoon stage was determined in the laboratory by using larval Japanese beetle, Popillia japonica Newman, as the host. Insecticides tested were imidacloprid, thiamethoxam, halofenozide, chlorpyrifos, and carbaryl at labeled rates. Female T. vernalis were allowed 2 d to parasitize P. japonica larvae after the parasitoids had received a 4-d exposure to insecticide-treated soil. Another group of female T. vernalis were allowed 2 d to parasitize P. japonica larvae that had been exposed to insecticide-treated soil for 3-4 d. Percentage of parasitism of P. japonica larvae in these trials after exposure of adult parasitoids to carbaryl, chlorpyrifos, halofenozide, or imidacloprid-treated soil (23.3-50.0%) or adult parasitoids to chlorpyrifos, halofenozide, or imidacloprid treated grubs (33.0 -56.7%) was not negatively affected relative to the control treatment (21.7-54.2%). A third group of adult T. vernalis and P. japonica larvae were simultaneously exposed to chlorpyrifos or carbaryl treatments. Percentage parasitism in these trials was lower for T. vernalis adults exposed to the chlorpyrifos and carbaryl (15.0-25.0%) relative to the control (57.5-62.5%) with the exception of one trial with carbaryl (40.0%). However, exposure of the parasitoid and P. japonica to chlorpyrifos 0.5×, carbaryl 0.5×, imidacloprid, halofenozide, or thiamethoxam in several trials resulted in parasitism that was equivalent or greater than (45.0- 80.0%) the untreated control (57.5-62.5%). Japanese beetle larval mortality in these trials was greater in the insecticide and parasitoid combination (97.5-100.0%) than with insecticides alone (45.0-100.0%). Percentage of survival of T. vernatis progeny to the cocoon stage was not negatively affected by a 4-d adult parasitoid exposure to carbaryl and chlorpyrifos treated soil (11.7-16.7% versus 18.3% control) or a 2-d exposure to p. japonica-treated larvae (16.7-18.3% versus 28.3% control). However, simultaneous exposure of T. vernalis progeny and P. japonica larvae to chlorpyrifos and carbaryl-treated soil resulted in no parasitoids surviving to the cocoon stage. Between neonicotinoids, thiamethoxam had more adverse impact on percentage parasitism (52.5%) and survival to the cocoon stage (10.0%) than imidacloprid (80.0 and 32.5%, respectively). Results of this study indicate soil incorporation of imidacloprid and halofenozide had minimal effect on the number of P. japonica larvae parasitized by T. vernatis or survival of T. vernalis progeny to the cocoon stage; therefore, they are more suitable for use with T. vernalis. In contrast, chlorpyrifos, carbaryl, and thiamethoxam lowered the number of T. vernalis progeny surviving to the cocoon stage, and carbaryl and chlorpyrifos reduced the number of P. japonica larvae parasitized. The soil incorporation of insecticides is discussed as one explanation for the minimal effects of some insecticides on T. vernalis. [ABSTRACT FROM AUTHOR]

We examined the effects of supplemental food sources on parasitism of turf-infesting white grubs (Coleoptera: Scarabaeidae) by tiphiid wasps (Hymenoptera: Tiphiidae). Survival of spring active Tiphia vernalis Rohwer and late summer active Tiphia pygidialis Allen, parasitoids of Japanese beetle, Popilliajaponica Newman, and masked chafer, Cyclocephala spp., grubs, respectively, was significantly increased when wasps were provided with 10% sugar water in the laboratory. Presence of a grub for host feeding did not affect wasp longevity. Sugar sprays applied directly to turf were examined as a method for increasing grub parasitism rates. Large numbers of T. pygidialis visited turf sprayed with sugar water to feed. Parasitism of Cyclocephala spp. grubs by T. pygidialis was reduced in sugar-sprayed turf, but higher in turf plots located near sugar-sprayed tuff. T. vernalis, which feeds on homopteran honeydew secretions, was never observed feeding on sugar-sprayed tuff, nor did such treatments affect its parasitism of P. japonica in or near sugar-sprayed turf. Gardens of spring- or fall-blooming flowering plants were established and monitored to determine whether particular species might attract Tiphia spp. No T. pygidialis were observed feeding on flowers in fall-blooming gardens. Large numbers of T. vernalis were observed feeding on nectar from peony, Peonia lactiflora Pallas, in the spring-blooming garden. When replicated plantings of P. lactiflora were established in a stand of turf, parasitism of P. japonica was significantly higher near the peonies. Incorporating such nectar-producing flowers into a landscape may increase parasitism of P. japonica by T. vernalis. [ABSTRACT FROM AUTHOR]

The events leading to oviposition by Tiphia pygidialis Allen and Tiphia vernalis Rohwer on their host Cyclocephala spp. and Popillia japonica Newman grubs, respectively, were compared and quantified using videotaped recordings. Mean (±SE) duration of the oviposition process was 49.3± 2.9 min for T. pygidialis and 31.5 ± 2.2 min for T. vernalis. Behaviors included stinging, moving soil from around grubs, host kneading, host examination, host feeding, and scraping of the grub's cuticle. Sequence of behavioral events was translated into a first-order (Markovian) contingency table to construct flow charts of the oviposition process for both species. T. pygidialis spent more time kneading and scraping the cuticle of grubs than did T. vernalis, whereas T. vernalis performed more stinging and soil-moving events. These behaviors most likely serve to move the grubs into a suitable position for oviposition. Scraping of the host's cuticle where an egg was to be laid took more time than any other behavior. Compared with nonparasitized grubs, cuticle from parasitized grubs contained numerous grooves filled with cement used to anchor the parasitoid egg. Scanning electron microscopy revealed peg-like structures, similar in size to the grooves made in the cuticle of parasitized grubs, on the ovipositor sheath of female wasps. These structures are thought to be used in making the grooves in the cuticle, whose postulated function is to increase the surface area of the host cuticle to facilitate egg attachment. This is the first study to implicate such use of the ovipositor sheath by a parasitoid. [ABSTRACT FROM AUTHOR]