Factors Influencing Oviposition in \u3ci\u3eAedes Triseriatus\u3c/i\u3e (Diptera: Culicidae)

Five factors associated with natural oviposition sites were tested for their attractancy to ovipositing Aedes triseriatus, including dyed oviposition water, presence of decaying organic matter, a dark oviposition container, water in which conspecific larvae have been reared to the 4th instar and the presence of eggs on the balsa wood oviposition substrate. A replicated fractional factorial design was used to examine the effects of the above factors on oviposition behavior in laboratory experiments. Regression analysis showed dyed oviposition water and eggs on the oviposition substrate to be statistically significant attractants for ovipositing A. triseriatus females. The attraction to dyed oviposition water indicated that dyed water in oviposition traps may greatly increase their competiveness with naturally occurring oviposition sites

Suboptimal Larval Habitats Modulate Oviposition of the Malaria Vector Mosquito Anopheles coluzzii.

Selection of oviposition sites by gravid females is a critical behavioral step in the reproductive cycle of Anopheles coluzzii, which is one of the principal Afrotropical malaria vector mosquitoes. Several studies suggest this decision is mediated by semiochemicals associated with potential oviposition sites. To better understand the chemosensory basis of this behavior and identify compounds that can modulate oviposition, we examined the generally held hypothesis that suboptimal larval habitats give rise to semiochemicals that negatively influence the oviposition preference of gravid females. Dual-choice bioassays indicated that oviposition sites conditioned in this manner do indeed foster significant and concentration dependent aversive effects on the oviposition site selection of gravid females. Headspace analyses derived from aversive habitats consistently noted the presence of dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS) and 6-methyl-5-hepten-2-one (sulcatone) each of which unitarily affected An. coluzzii oviposition preference. Electrophysiological assays across the antennae, maxillary palp, and labellum of gravid An. coluzzii revealed differential responses to these semiochemicals. Taken together, these findings validate the hypothesis in question and suggest that suboptimal environments for An. coluzzii larval development results in the release of DMDS, DMTS and sulcatone that impact the response valence of gravid females

Chemical Cues for Malaria Vectors Oviposition Site Selection:\ud Challenges and Opportunities

The attractiveness of oviposition site for malaria vector mosquitoes is dependent upon a number of physical and chemical factors. Many aspects of mosquito behavior, including host location and oviposition, are mediated by volatile semiochemicals. It is anticipated that selection of oviposition site by semio-chemicals in the form of attractants or stimulants can be used in oviposition traps to monitor or possibly in combination with insecticides to control gravid mosquito populations for mass trapping. So far, volatile compounds identified as oviposition attractants for mosquitoes include phenol, 4-methyl phenol, 4-ethyl phenol, indole, skatole, and p-cresol from hay infusions; 3-carene, terpinene, copaene, cedrene, and d-cadinene released by copepods; alcohol and terpenoids including p-cresol fromplants; ethyl acetate and hydrocarbon substances, probably released by filamentous algae; 3-methyl-1-butanol identified frombacteria. Research priorities should be directed at identifying more oviposition attractants to determine the properties of these semio-chemicals for possible use in designing control tools. This would aim at luring females to lethal traps or stimulants to increase their exposure to insecticide-impregnated substrates.\ud \u

Oviposition by the Banded Sunflower Moth, \u3ci\u3eCochylis Hospes\u3c/i\u3e (Lepidoptera: Cochylidae) in Response to \u3ci\u3eHelianthus Annuus\u3c/i\u3e Pollen

Oviposition on an artificial substrate by the banded sunflower moth Cochylis hospes Walsingham was examined in response to sunflower pollen (Helianthus annuus) and sunflower pollen extract. Sunflower pollen in quantities as small as 0.2 mg significantly reduced oviposition on an artificial substrate relative to a control without pollen. Aqueous pollen extract applied to the artificial substrate significantly reduced oviposition with respect to the control substrate that was treated with solvent. Banded sunflower moths have gained some reproductive or competitive advantage by ovipositing on the bracts of sunflower and a deterrent effect of pollen could, at least in part, have had functional significance in the development of a behavioral preference for the bracts of the sunflower head as an oviposition site

Honeylocust Twig-gall Midge (Diptera: Cecidomyiidae) in Michigan

Emergence and oviposition data were gathered for Neolasioptera brevis, a recently described pest of honeylocust. In 1984 the insects first emerged on 21 May and first oviposited on 4 June; in 1985 they first emerged on 28 April and first oviposited between 5-20 May. Average raceme length at emergence and at oviposition were 2.7 and 4.4 cm in 1984 and 2.6 and 4.8 cm in 1985. Approximate duration of the emergence period was one week. In 1985 observed oviposition wounds averaged 0.5/cm

Phenology of Oviposition of \u3ci\u3eDasyneura Oxycoccana\u3c/i\u3e (Diptera: Cecidomyiidae) in Relation to Cranberry Plant Growth and Flowering

Eggs of cranberry tipworm, Dasyneura oxycoccana (Diptera: Cecidomyiidae) were sampled in a Wisconsin cranberry marsh from 1990 through 1992. Oviposition began in May within one week after the first cranberry shoots elongated more than 5 mm. Oviposition fluctuated in June, then greatly decreased in July, after over 90% of cranberry flowers had opened. Some oviposition continued into August. Tipworm probably has greatly overlapping generations, as no distinct broods could be detected. Consequently, D. oxycoccana may be difficult to manage without control methods effective against multiple life stages

EVIDENCE OF COMMUNAL OVIPOSITION AND NEST ABANDONMENT IN THE NORTHERN TWO-LINED SALAMANDER (EURYCEA BISLINEATA, (GREEN, 1818)) IN NORTHEASTERN CONNECTICUT

Most plethodontid salamanders oviposit their eggs in an individual nest and attend the clutch until hatching. Here, we describe aspects of the reproduction of Eurycea bislineata (Northern Two-lined Salamander) from three field sites in northeastern Connecticut that contrast with the typical plethodontid reproductive behavior. Rocks used as oviposition sites contained up to 296 eggs, with an average of more than 100. These numbers exceed the maximum ovarian egg counts for this species, indicating that communal oviposition is common. The lack of correlation between rock size and number of eggs, as well as the lack of discrete clutches when eggs are laid in large clusters, suggests that communal oviposition may be caused by something other than nest site limitation. Additionally, the rate of maternal attendance at nests was low. Thus, communal oviposition with high rates of nest abandonment is the dominant reproductive strategy in E. bislineata at these sites

Effect of Habitat on Blow Fly (Diptera: Calliphoridae) Oviposition in Michigan

Forensic entomology applies data gained from insects to aid the criminal justice system. Blow flies (Diptera: Calliphoridae) are usually the first insects to arrive and oviposit (lay eggs) on carrion. Their quick appearance is the foundation for post mortem interval estimations, making any factors that influence their oviposition crucial. This study examined the effects of habitat (forest vs. prairie) on blow fly oviposition timing. Research was conducted in 2015 at Pierce Cedar Creek Institute in Barry County, Michigan. No significant differences were found in oviposition timing or frequency between prairie and forest habitats. Temperature and humidity were not correlated with oviposition timing, which contradicted previous studies. Lucilia coeruleiviridis (Macquart) was the dominant species found, comprising about 90% of collected specimens. The data confirm previous reports that Lucilia species are the first to arrive on carrion

Diurnal Oviposition of Blow Flies in Different Aged Carrion

Blow flies (Diptera: Calliphoridae) are among the first insects to oviposit (lay eggs) on carrion. The timing of blow fly oviposition is critical for determining a postmortem interval (PMI) estimation, which is the time that has passed between death and corpse discovery. The objective of this investigation is to gain more information about the timing of blow fly oviposition in relation to sunrise. Past research in our lab has shown that blow fly oviposition occurs an average of 4.75 hours after sunrise. This year’s research expanded on previous studies by placing six piglets of different ages, in a remote, wooded area one hour after sunrise. To see if there was a difference in the timing of oviposition related to the age of the carrion, three of the piglets had been thawed for 15 hours (new pigs), and the other three had been thawed for approximately 55 hours (old pigs). The piglets were checked once an hour until oviposition occurred, and it was recorded whether flies and eggs were present each hour. Egg masses were collected and reared to the third larval instar stage for identification using taxonomic keys. The timing of oviposition, in hours after sunrise, was compared between treatments and there was no significant difference found (P=.441). The research was repeated five times in the fall of 2017. The most common flies found ovipositing were Diptera: Calliphoridae, Phormia regina (Meigen) and Diptera: Calliphoridae, Lucilia coeruleiviridis (Macquart). This research has importance in both the scientific and forensic communities, as a more accurate PMI can strengthen the validity of a forensic investigation