2024 Caterpillar Season – Red-fringed Emerald

Red-fringed Emerald
Nemoria bistriaria fam. Geometridae
Host plant: Found on white oak (Quercus alba)
Date found: 7, Sep, 2024
Locations Found: Kaintuck Hollow, Phelps County, MO
Notes: Although some reports suggest other host plants are used, it is likely that this species specializes on white oak.

A Beautiful Ichneumonid

This post is related to the rearing work I shared previously of the Orgyia leucostigma (white-marked tussock moth). During a caterpillar hunting outing with Sarah, I found what was obviously a cocoon of a tussock moth. I can’t say for certain it belonged to O. leucostigma, but it is likely. So, I photographed it in the field and brought it home, keeping it separate from the O. leucostigma cocoons that I was rearing that were collected from my yard. As time went on and the other cocoons I was rearing began producing moths, I figured something was going to be different with the one pictured below.

A tussock moth (Orgyia sp.) cocoon collected on 21, Sep, 2024 at Onondaga Cave State Park. Note the long setae from the tussock moth caterpillar that are incorporated into their cocoons

Checking the container on 6-October, I found this beautiful Orgichneumon calcatorius, an Ichneumonid wasp with a Holarctic range that is a parasitoid of moths in the Orgyia and Dasychira genera. After taking a few photos, I let it go in the backyard. After emerging, females of the species mate and then overwinter as adults utilizing crevices in tree bark. In the spring and summer of the following year, they look for new caterpillars to insert their eggs.

A newly emerged Orgichneumon calcatorius with the pupa and cocoon that hosted it in the background.
A closeup look of the brilliantly patterned Orgichneumon calcatorius

2024 Caterpillar Season – Small Necklace

Small Necklace Moth
Hypsoropha hormos fam. Erebidae
Host plant: Found on persimmon (Diospyros virginiana)
Date found: 3, Aug, 2024
Locations Found: Cuivre River State Park, St. Louis County, MO
Notes: Described by one of the fathers of entomology, German lepidopterist, Jacob Hübner.

2024 Caterpillar Season – Virginia Creeper Sphinx Moth

Virginia Creeper Sphinx Moth
Darapsa myron fam. Sphingidae
Host plant: Found on wild grape (Vitis sp.)
Date found: 13, Sep, 2024
Locations Found: River’s Edge Park, St. Louis County, MO
Notes: Other common name is hog sphinx.

2024 Caterpillar Season – Lace-capped Caterpillar

Lace-capped Caterpillar
Ianassa lignicolor fam. Notodontidae
Host plant: Oaks and other Fagaceae members
Date found: 21, Sep, 2024
Locations Found: Onondaga Cave State Park, Crawford County, MO
Notes: Adult moth is named white-streaked prominent.

Ianassa lignicolor
Characteristic head mottling of Ianassa lignicolor head capsule

2024 Caterpillar Season – Nason’s Slug Moth

Nason’s Slug Moth
Natada nasoni fam. Limacodidae
Host plant: Found on oak (Quercus sp.)
Date found: 07, Sep, 2024
Locations Found: Kaintuck Hollow, Phelps County, MO
Notes: Named after William Abbott Nason, American entomologist (1841-1914).

2024 Caterpillar Season – Variable Oakleaf Caterpillar

Variable Oakleaf Caterpillar
Lochmaeus manteo and L. bilineata fam. Notodontidae
Host plant: Found on oaks (Quercus sp.)
Date found: Multiple dates in August – September, 2024
Locations Found: Hawn State Park, Ste. Genevieve County, MO; Onondaga Cave State Park, Crawford County, MO
Notes: Highly variable and larvae are apparently impossible to distinguish between the two species.

First, a glimpse of the variable patterns and colors of these cats.

The adult photographed at Schoolcraft Prairie in Washington County, MO in mid-August, 2024.

2024 Caterpillar Season – White-dotted Prominent

White-dotted Prominent
Nadata gibbosa fam. Notodontidae
Host plant: Found on white oak (Quercus alba)
Date found: 02, Sep, 2024
Location Found: Hawn State Park, Ste. Genevieve County, MO
Notes: One of the most common finds while searching oak trees.

2024 Caterpillar Season – Monkey Slug

Monkey Slug Moth (Hag Moth)
Phobetron pithecium fam. Limacodidae
Host plant: Found on oak (Quercus sp)
Date found: 02, Sep, 2024
Location Found: Hickory Canyon Natural Area, Ste. Genevieve County, MO
Notes: One theory to explain their appearance is that they evolved to mimic the shed exoskeletons of tarantulas.

2024 Caterpillar Season – Maple Spanworm

Maple Spanworm
Ennomos magnaria fam. Geometridae
Host plant: Found on ash (Fraxinus sp)
Date found: 02, Sep, 2024
Location Found: Hickory Canyon Natural Area, Ste. Genevieve County, MO
Notes: While caterpillars of this species are perfect twig mimics, the adults of this species look amazingly like autumn-turned maple leaves.