Friday, October 11, 2019

Friday Ramble - Waspish

 American Pelecinid Wasp (female)
(Pelecinus polyturator)
The lady looks dangerous, but there is no need for concern. She is a placid creature, and not malignant at all. The glossy curling appendage is actually an ovipositor, used to deposit her daughter eggs on underground beetle larva.
American pelecinids are sometimes called scorpion flies, but they are not related to either scorpions or true scorpion flies, and they don't have stingers. As adults, they feed on nectar and are important pollinators of fruit trees and wildflowers, a role they share with other wasps, bumbles, honey bees and hoverflies. They have a particular fondness for late blooming goldenrod, and that is where I encounter them from time to time, but these are the first images I have ever been able to capture. There was a strong north wind in the field that morning, and I was surprised that any of my clumsy efforts turned out.

Wasps of this species reproduce parthenogenetically, and they do not need males for procreation, a proliferation strategy that probably originated in the general scarcity of male pelecinids in the northern hemisphere. Obviously, the same strategy also serves to perpetuate the rarity of males of the species. Early pelecinid specimens have been found preserved in amber, and males seem to have been just as scarce in ancient times as they are now.

Of the three species in the genus, ours is the only one that reproduces without a mate. Lacking a male parent, the offspring are all female of course, exact copies (or clones) of the mother's genetic matrix. Scientists studying American pelecinid populations think that the genetic variations necessary for the survival of the species may be provided by mutation, including the birth of a male now and then. Male pelecinids are rare indeed, and if you encounter one of these exquisite creatures in the wild, chances are it is female. Not needing an ovipositor, the males have much shorter tails.

Encountering this female in a stand of goldenrod a few days ago, I was happy to make her acquaintance. She was beautiful, and I loved her expression.

3 comments:

One Woman's Journey - a journal being written from Woodhaven - her cottage in the woods. said...

I continue to learn from you

Dee said...

Well, I learned something. I LOVE this photo. Thank you for sharing.
Dee

Kay G. said...

Fascinating, as always.