I've been able to capture moths at mercury vapour lights and recognize females using two methods:
1) examination of abdomen--females tend to have a shorter "turkey baster" shape while males have abdomens which taper consistently and gradually.
2) examination of frenulum--males have a single stiff spine at the top of the hindwing very close to the juncture with the thorax; females have multiple, softer spines which project at an angle closer to the wing.
When I capture a moth whose abdomen seems to indicate it is a female, I examine the frenulum for confirmation.
I hold the moth at the base of the forewings between the thumb and index finger of one hand and gently use the other forefinger or thumb to put some (considerable) separation between the hindwing and the forewing.
I'm getting better with experience and can usually spot the male "spine" in bright light when my initial diagnosis has been wrong. A hat-, partner- or mouth-held flashlight will probably be necesssary in the field.
I separated the forewings of a
few "euthanized" males from their bodies and examined the frenula. |
Confirmed females were placed in inflated brown paper grocery bags and have thus far deposited eggs on the flat sides and bottom of the grocery bag, in folds of a wrinkled/crinkled brown paper sandwich bag added to the "housing unit" and even on a crinkled napkin moistened with a sugar/fruit mix and placed on the bottom of the grocery bag.
It may be necessary to put moths in sleeves over appropriate hosts to get maximum egg deposition.
It is difficult to get high quality photographs of eggs which are extremely small, much smaller than typical Saturnidae and Sphingidae eggs. Relicta a very dark grey brown while those of concumbens have a rosy hue. The Kirby Wolfe images below are the best I have seen and reveal some of the intricacy of these finely sculpted orbs.
Catocala concumbens courtesy of Kirby Wolfe
Catocala relicta courtesy of Kirby Wolfe.
Others, still affixed to paper strips, will be stored outside in a plastic jar with some air holes in the lid. I'll put the jar(s), carefully labelled as to species, in a camping cooler and store it out of direct sunlight on a balcony on the north side of the house.
Hopefully I will have larvae in the spring. Those eggs in the microcentrifuge tubes (just to further conserve moisture) will be taken out of cold storage when poplar foliage becomes available, poured out of the tubes into a litre (approx. quart) sized clear plastic storage tub, lid on tight and no air holes, kept at room temperature and watched carefully for newly emerged larvae.
Those eggs stored outdoors will receive similar treatment when poplar leaves have opened.
Foliage will only be offered once eggs have hatched. Some larvae will be reared indoors on cut food in airtight containers and other larvae will be reared outdoors in sleeves.
It is my hope to get scans of the larvae in each of the instars.
At maturity, the larvae wil be moved to pupation buckets or tubs.It is my understanding that usually the pupae are covered with a powdery bloom, and they emerge in two to three weeks. Catocala aholibah pupa courtesy of Jeremy B.Tatum and Dr. John Snyder. |
"Catocala ilia are placed in a paper bag for 2 -3 nights with no food. Adults are removed to outdoor screened cages in the morning and sprayed heavily with water three times and then placed back in the bags at dusk. On the 4th night I introduce my bait mixture on a container lid at the bottom of an inflated grocery bag.
"I take two pieces of burr oak bark and wire it onto both sides of the bag and the females will dump just about all their eggs the 4th night."