Synonyms and other taxonomic changes
Thyreodon atricolor (Olivier, 1812)
= Thyreodon morio transversalis Viereck [!] misspelling of transitionalis?
= Orig. comb.: Ophion atricolor Olivier, 1812
Thyreodon atricolor atricolor (Olivier, 1812)
= Thyreodon brullei Viereck, 1917
= Thyreodon morio Auctt., non Fabricius
= Ophion morio Auctt., non Fabricius
=
Ichneumon morio Auctt., non
Fabricius, 1781
= Orig. comb.: Ophion atricolor Olivier, 1812
Thyreodon atricolor flavicornis (Say, 1823)
= Thyreodon morio transitionalis Viereck, 1906
= Thyreodon snowi Viereck, 1905
= Orig. comb.: Anomalon flavicornis Say, 1823
Numbers
2 sspp. recognized with distinct geographic separation:
(1)
1. Thyreodon atricolor atricolor: widespread eastern (QC west to MB, south to FL and e. TX)
2. Thyreodon atricolor flavicornis: western (AZ, CO, se. ID, w. KS, NM, UT)
Identification
A very distinct and large species with a black body, black wings, and orange-yellow antennae. Distinguishable as an Ophioninae by the laterally compressed abdomen with a distinct, circular "knob" between the first and second segments. Further distinguishable as a
Thyreodon by the very large, bulging propodeum. Unlike most Ophioninae, however, the ocelli are very small and inconspicuous.
(2) The basal tarsomere is just slightly shorter than the total length of subsequent tarsomeres, not slightly longer as in
Therion or nearly twice as long as in
Heteropelma (both Anomaloninae: Gravenhorstiini).
Variability
Wings with a fulvo-hyaline (yellowish translucent) spot around the discosubmarginal cell
(3)
Face and legs flavous or ferruginous
(3)
Range
The most northern species of the genus, occurring in our area from latitudes in Texas all the way into Canada,
(3)and from the east coast west to MB, se. ID, CO, and AZ.
(1)
* BugGuide evidence for as far west as SK
Food
Larval hosts: caterpillars of Sphingidae including
Lapara bombycoides (northern pine sphinx moth),
Lapara coniferarum (southern pine sphinx moth), and
Paonias excaecatus (blinded sphinx moth)
(2)Life Cycle
Diurnal unlike most other Ophioninae, which are nocturnal.
(3)Remarks
"Although most members of the huge family Ichneumonidae are difficult to identify, this large species is an easily recognized, day active, slow flying parasitoid of sphinx moth caterpillars."
See Also
Therion morio is a smaller black ichneumonid with yellow-marked hind legs. Females have a longer, more visible ovipositor. They also have a more strongly elongate basal segment of the hind tarsus, with the following segments significantly shortened.
Therion nigripes and T. tenuipes are smaller black ichneumonids and the only member of its genus with dark hind legs like Thyreodon atricolor. As with Therion morio, females have a longer, more visible ovipositor, and both sexes have a strong difference in the length of the hind tarsal segments.
Gnamptopelta obsidianator is another mimic of tarantula-hawk wasps and allied members of Pepsini. The abdomen isn't laterally compressed as in Thyreodon or Therion. This species also has a characteristically pyramidal scutellum.
Conocalama brullei is structurally very similar to G. obsidianator, except that the scutellum is shelf-like rather than pyramidal and that the first segment of the abdomen has a conical projection at the base.