Ichneumonidae

Ichneumons are a diverse group of parasitic wasps. Female ichneumons lay their eggs on or in a living host, usually an insect or spider. When the larvae hatch, they begin to feed on the host, frequently eating it in such a way as to allow it to remain alive for as long as possible, permitting the larvae to complete their development. The host is literally eaten alive.

In 2019, a group of international entomologists suggested the name “Darwin wasps” for this family, in reference to a famous letter that Darwin wrote in 1860 to American botanist Asa Gray. He wrote: “I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice.” (Darwin solved this vexing issue by saying that there is no solution. Nature is not cruel or evil, and does not exist to offer us moral lessons; it just exists.)

Gross as endoparasitism sounds, these wasps play an important role in regulating insect populations. This specimen was in my dining room … looking for caterpillars??

Dermacentor variabilis

Ticks are parasitic arachnids of the order Ixodida. They live by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians. They’ve been around for a long time; the oldest known tick fossils are from the Cretaceous period, around 100 million years old.

I’d never heard of the American dog tick (or wood tick) till I brought one home on my neck last weekend. They mostly live east of the Rocky Mountains. Dermacentor variabilis is a three-host tick—the larva, nymph and adult all need to ingest blood.

Some ticks attach to their host rapidly, while others wander around searching for thinner skin, such as that in the ears of mammals. Mine was obviously still on the hunt for a good feeding site. Reading up on tularemia and Rocky Mountain spotted fever, I’m glad I removed it before it latched on!

Pholcus phalangioides

I thought I’d learn a bit more about our most common spider, the ubiquitous daddy long-legs, also known as the cellar spider. As a synanthrope (an organism that lives near and benefits from humans and their environmental modifications), these spiders can be found on every continent in the world. They prefer the warmth inside human dwellings; daddy long-legs living outdoors can be found in the dimly-lit, calm environment of caves and in between rock crevices.

It takes about one year for these spiders to mature after they are born, and their life span can be two years or more post-maturity.

There is a common misconception that this spider’s venom is extremely dangerous but that their fangs are too short to pierce human skin. Neither statement is true. The fangs are longer (0.25mm) than the epidermis is thick (0.1mm); the venom has a negligible effect on mammals, including humans. So let’s put that urban legend to bed.

Phoca vitulina

Annette and I drove up the coast a ways to join the Channel Island Nature Journalers for a windswept nature journaling session at Carpinteria. (Note to my Australian friends: the emphasis is on the penultimate syllable, Car-pin-ter-REE-a) A good (blustery) time was had by all.