Ceratogastra ornata

(Say, 1835)

Ceratogastra ornata is a small ichneumon (10–12 mm) recognized by its ornate yellow and reddish-brown or black coloration. Four are recognized across its broad North American range, with northern specimens darker and more reduced in yellow markings than southern and western . The has been suggested to mimic stinging in appearance. Females are known to oviposit in flower buds, targeting or early of in the Feltia.

Ceratogastra ornata by (c) Owen Strickland, some rights reserved (CC BY), uploaded by Owen Strickland. Used under a CC-BY license.

Ceratogastra ornata by (c) Gordon C. Snelling, some rights reserved (CC BY), uploaded by Gordon C. Snelling. Used under a CC-BY license.

Ceratogastra ornata sicca by the Smithsonian. Used under a CC0 license.

Pronunciation

How to pronounce Ceratogastra ornata: /sɛrətoʊˈgæstrə ɔrˈneɪtə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from similar () by antennal structure: ichneumon have many short antennal versus fewer, longer segments in spider wasps. differs but is difficult to observe in the field. The "horse " in the forewing is visible in good images. Resembles spider wasps in the Poecilopompilus and Ceropales in coloration and pattern, but these are generally larger.

Images

Appearance

Small , 10–12 mm in body length. Ornately patterned with yellow and reddish-brown or black, with geographic variation in color intensity. Northern specimens generally darker with reduced yellow markings and darkened ; southern and western specimens distinctly paler. with many short (characteristic of ichneumon wasps). Wings with venation including a "horse " near the middle of the forewing, with the "nose" pointed toward the wingtip.

Habitat

Found in varied across its range. frequently visit flowers, especially composites (Asteraceae).

Distribution

North America, from southern Ontario, Massachusetts, and southern Wisconsin west to eastern California and south to northern Florida, Louisiana, and Mexico. Four recognized with geographic variation in coloration.

Diet

feed on nectar from flowers, including . are internal of in the Feltia.

Host Associations

Feltia - or newly-hatched of in this are the larval . Female oviposit into flower buds where eggs have been laid.
Ambrosia artemisiifolia - siteCommon Ragweed; observed site for by female .
Eupatorium - siteThoroughworts; observed site for .
Helianthus annuus - nectar sourceCommon Sunflower; observed feeding at , but not known to oviposit here.

Life Cycle

Complete with larval stage. Female injects into egg or early . develops internally as , likely allowing host to mature partially before feeding in earnest and ultimately killing it. presumably occurs within or near host remains, though details are not fully documented.

Behavior

Females visit flowers to obtain nectar and to locate . involves probing flower buds with the , appearing to "sting" the flower but actually targeting concealed or . have been observed on goldenrod flowers but do not oviposit there.

Ecological Role

of , potentially regulating of pests. Acts as while foraging for nectar.

Human Relevance

agent for certain agricultural pests (). Subject of citizen science through image documentation on platforms such as Bugguide.net, where observations contribute to knowledge of distribution and .

Similar Taxa

Poecilopompilus suggested as model for ; similar color pattern but larger size and different antennal structure.
Ceropales observed as potential model in Colorado Springs; similar appearance but larger size and fewer, longer antennal .

More Details

Mimicry

Suggested to be a mimic of stinging , with striking similarities in color and pattern to Poecilopompilus and Ceropales .

Taxonomic Authority

described by Thomas Say in 1835.

Research Needs

and geographic range of most ichneumonid remain poorly known; image documentation encouraged to advance understanding.