Reduction of Gypsy Moth Male Mating Potential in Dense Populations by Mistblower Sprays of Microencapsulated Disparlure1

J. Granett; C. C. Doane

doi:10.1093/jee/68.4.435

Bounds on Absolute Gypsy Moth (Lymantria dispar dispar) (Lepidoptera: Erebidae) Population Density as Derived from Counts in Single Milk Carton Traps

Insects ◽

10.3390/insects11100673 ◽

2020 ◽

Vol 11 (10) ◽

pp. 673

Author(s):

Ksenia S. Onufrieva ◽

Alexey V. Onufriev ◽

Andrea D. Hickman ◽

James R. Miller

Keyword(s):

Population Density ◽

Gypsy Moth ◽

Management Strategies ◽

Dispersal Distance ◽

Upper And Lower Bounds ◽

United States Department ◽

Department Of Agriculture ◽

Moth Male ◽

Monitoring Traps ◽

Absolute Population

Estimates of absolute pest population density are critical to pest management programs but have been difficult to obtain from capture numbers in pheromone-baited monitoring traps. In this paper, we establish a novel predictive relationship for a probability (spTfer(r)) of catching a male located at a distance r from the trap with a plume reach D. spTferr=spTfer01+rD2, r≤Rmax0, r>Rmax, where spTfer(0) is the probability of catching an insect located next to the trap and Rmax is the maximum dispersal distance for the insect during the trapping period. The maximum dispersal distance for gypsy moth is known to be 1600 m. The probability of catching a gypsy moth male located next to a United States Department of Agriculture (USDA) milk carton pheromone-baited trap is 0.37, the overall probability of catching a male from the entire trapping area (Tfer) of ~800 ha is 0.0008, and plume reach of this trap is D = 26 ± 3 m. The equation for spTfer(r) is used to derive statistical upper and lower bounds (95% confidence interval) on the population density for the given value of a single trap catch. This combination of trap parameters appears to produce an effective trap: even a catch of 1 male provides meaningful lower and upper bounds on absolute population density. Applications in the management programs are discussed, and a look-up table is provided to translate the catches in USDA milk carton pheromone-baited traps to absolute population bounds, which can help design better management strategies.

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The Effects of the sphragis on male and female genitalia in Acraea (Nymphalidae) butterflies

UF Journal of Undergraduate Research ◽

10.32473/ufjur.v22i0.121244 ◽

2020 ◽

Vol 22 ◽

Author(s):

Shannon L Summers ◽

Akito Y Kawahara ◽

Ana P. S. Carvalho

Keyword(s):

Interspecific Variation ◽

Sperm Storage ◽

Male Mating ◽

Museum Collections ◽

Storage Organ ◽

Mating Plug ◽

Males And Females ◽

Comparison And Analysis ◽

Imagej Software ◽

Sexually Antagonistic Coevolution

Male mating plugs have been used in many species to prevent female re-mating and sperm competition. One of the most extreme examples of a mating plug is the sphragis, which is a large, complex and externalized plug found only in butterflies. This structure is found in many species in the genus Acraea (Nymphalidae) and provides an opportunity for investigation of the effects of the sphragis on the morphology of the genitalia, which is poorly understood. This study aims to understand morphological interspecific variation in the genitalia of Acraea butterflies. Using specimens from museum collections, abdomen dissections were conducted on 19 species of Acraea: 9 sphragis bearing and 10 non-sphragis bearing species. Genitalia imaging was performed for easier comparison and analysis and measurements of genitalia structures was done using ImageJ software. Some distinguishing morphological features in the females were found. The most obvious difference is the larger and more externalized copulatory opening in sphragis bearing species, with varying degrees of external projections. Females of the sphragis bearing species also tend to have a shorter ductus (the structure that connects the copulatory opening with the sperm storage organ) than those without the sphragis. These differences may be due to a sexually antagonistic coevolution between the males and females, where the females evolve larger and more difficult to plug copulatory openings and the males attempt to prevent re-mating with the sphragis.

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