Friday, September 23, 2022

Rusty Spider Wasp


Building her nest - BC

Ben Caruthers comes through again with a great set of pictures.  He shot this red wasp and identified it as a rusty spider wasp (RSP), a lot easier to pronounce than its scientific name Tachypompilus ferrugineusThis is a large and impressive wasp that dives into its work head first.


 

Rusty spider wasp dragging a wolf spider across the ground
Click to enlarge - MDC

Spider wasps belong to the family Pompilidae.  These wasps visit flowers for nectar but their fame comes from killing spiders to feed the family.  The female stings her spider prey into paralysis and then drags the spider backwards to her nest, gripping the incapacitated spider with her mandibles.  The trip can be long and laborious as the spider is frequently much larger than the wasp.  Maybe that is why they call it going into labor?

Spider Wasp and Wolf Spider - Tachypompilus ferrugineus
With a wolf spider prey - Ted Kropiewnicki CC

Once the nest is prepared to her satisfaction, she grabs the spider and rolls it over so it is on top of her while she deposits a single egg before covering it with soil.  I frequently wonder how we know details like these but in this case it was observations by R.W. Strandtman described in this more detailed source.

The RSP specializes in collecting wolf spiders (Lycosidae).  Other species of spider wasps also tend to specialize in their spider prey, some with free living hunting species and others using web spiders.  The young wasp will get all its nutrition from this spider while all adults feed on nectar.

After this considerable effort to deliver and feed a single young, I wonder if she doesn't tell the next male that finds her, "Not tonight, I have a headache!"