I've previously shown you the cocoons of these silkmoths, and the spectacular coloration of the female. The top photo is of a typical male; when compared with the female the sexual dimorphism is quite apparent. The males have a black and brown color palette, quite attractive on close viewing, but at a distance when they are flying they look more like bats than moths.
When our female emerged she was emitting pheromones each afternoon beginning about 4 p.m. These attracted males from miles around; at one point we had about a dozen of them hovering around our screen porch and deck - much to the delight of the neighborhood children. As shown in the second photo above, the males exhibited a particular fascination with my house slipper; at one point I had four of them vigorously exploring the slipper. I suspect the coloration was similar enough to the female to evoke the response, and the pheromones were probably everywhere in the air.
The moth that eclosed from the second cocoon in the terrarium was a male, and he thus became the successful suitor to the female. We found him the following morning thoroughly exhausted and with battered wingtips on the floor of the terrarium; the female remained in pristine condition. Over the next few days she then proceeded to oviposit on the sticks and vegetation in the terrarium, and even on the glass walls (photo below). These should begin hatching in several weeks, after which I hope to be able to show you the growth stages of the remarkably colorful silkworm caterpillars.
Update August 2: The eggs were infertile. Over the next several weeks they became umbilicated with a central depression and wound up desiccated. I found a statement in an old text on Google Books that these changes indicate infertile eggs; I also learned in the process that a day or two after hatching, a female will start laying eggs - whether or not she has been fertilized.
Quite a disappointment for us.
She's gorgeous, but he's absolutely piss-elegant. Will he survive the mating? Will he go on to mate another day?
ReplyDelete@Swift Loris - the answer to your question was too sad to include in the text. The moths have no mouth parts. They can never feed. Their only purpose in life is to mate and produce eggs to create another generation of caterpillars. It's so sad that such exquisite beauty only lasts for a few days until they use up the energy stores they accumulated as fat caterpillars.
ReplyDeleteWe had moths on our bottle brush tree in Arizona that drank the necta from the flowers. So, this must not apply to all of them.
ReplyDeleteReally fascinating post there... too bad you are taking a break, I read your blog in between repainting my front porch and wall;)Now that the heat has broken, I guess we've got to get while the gettins' good.