Orgyia antiqua

Adult males distinguished from similar Orgyia species by orange-red forewings with white comma-shaped tornal spot and markedly plumose antennae. Flightless females with vestigial wings are unique among sympatric moths; grey-brown coloration and swollen abdomen aid recognition. Caterpillars unmistakable due to combination of dark body, red tubercles, and prominent hair tufts including four dorsal 'humps' and anterior/posterior 'horns' and 'tail' projections. In North America, may be confused with O. leucostigma (white-marked tussock moth) or O. pseudotsugata (Douglas-fir tussock moth), but O. antiqua males lack the white forewing markings of O. leucostigma and have different host plant associations than O. pseudotsugata.

Shrub-based habitats including gardens, parks, open woodland, fens, hedgerows, heaths, and moors. In North America, occurs in forested areas where host plants are present. Associated with birch woodlands in Scotland.

Native to Europe; transcontinental distribution in Palaearctic and Nearctic regions. Present in UK as common resident. GBIF records confirm presence in North America, Belgium, and multiple Belgian regions.

In UK, protracted single generation from July to October in south, September to October in north. In North America, one generation per year with adults flying from May to October. Caterpillars present May to early September in UK. Overwinters as eggs.

Polyphagous caterpillars feed on wide range of deciduous trees and shrubs including birch (Betula), hawthorn (Crataegus), lime (Tilia), Prunus, oak (Quercus), Rubus, willow (Salix), tamarisk (Tamarix), Vaccinium, and others. In Scotland, almost exclusively associated with birch; also recorded on Sitka spruce.

• Betula - primary hostespecially in Scotland
• Salix myrsinifolia - hostaffects pathogen resistance
• Salix viminalis - hosthigher phenolic glycosides, reduced larval growth but better pathogen resistance
• Crataegus - host
• Tilia - host
• Prunus - host
• Quercus - host
• Rubus - host
• Tamarix - host
• Vaccinium - host
• Picea sitchensis - hostrecorded damaging in Scotland

Eggs: several hundred laid on exterior of female's empty cocoon, attached to host plant or nearby structures; brownish, rounded, somewhat flattened with small darker depression on upperside; overwintering stage. Larvae: hatch early spring when foliage appears; present May to early September in UK; defensive glands at rear used to charge setae with toxins; females considerably larger than males. Pupae: formed in crevices inside silk cocoons. Adults: males fly in zigzag pattern, often high, diurnal or nocturnal, attracted to pheromone traps; females flightless, remain attached to cocoon, release pheromone to attract males.

Males fly in zigzag pattern, often at height, searching for females; active day or night and occasionally attracted to light. Females are sedentary, releasing pheromones from their cocoon to attract males via concentration gradient; mate and lay eggs on their own cocoon. Caterpillars exhibit defensive behavior: wipe setae against posterior glands to charge them with toxins. Group rearing affects individual condition (body weight, development time) but host plant species dominates pathogen resistance outcomes.

Herbivore in deciduous woodland and shrubland ecosystems; tritrophic interactions involving host plant quality, herbivore performance, and fungal pathogen (Metarhizium anisopliae) resistance. Minor forest pest in North America; potential urban pest in UK cities. Serves as host for nuclear polyhedrosis virus (OaNPV) which has been studied for cross-species infection potential with gypsy moth (Lymantria dispar).

Minor forest pest in North America; occasional pest in UK cities. Subject of pheromone disruption studies for potential management using (Z)-6-heneicosen-11-one. Genome sequenced as part of Darwin Tree of Life project. Used in research on insect-pathogen interactions, immune ecology, and evolutionary trade-offs between growth and resistance.

• Orgyia leucostigmaWhite-marked tussock moth; males have white forewing markings unlike O. antiqua's orange-red wings with single white comma spot; both share pheromone sensitivity to (Z)-6-heneicosen-11-one
• Orgyia pseudotsugataDouglas-fir tussock moth; conifer-feeding specialist in western North America, unlike polyphagous O. antiqua; females also flightless but associated with Douglas-fir forests
• Dasychira plagiataConifer-feeding tussock moth; also susceptible to pheromone disruption with same compound, but in different genus with different host associations

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Plant hunting in South Essex - Buglife Blog - Buglife
• Bug Eric: National Moth Week Recap, 2015
• Bug Eric: National Science Foundation Suspends Funding Support for Biological Collections
• RFID Tracking: Where It Fits in an Entomologist's Toolbox
• How Students Can Get Involved Entomological Preservation Projects
• Hate mail | Beetles In The Bush
• DISRUPTION OF PHEROMONE COMMUNICATION OF THE RUSTY TUSSOCK MOTH, ORGYIA ANTIQUA (LEPIDOPTERA: LYMANTRIIDAE), WITH (Z)-6-HENEICOSEN-11-ONE
• Pathogen resistance in the mothOrgyia antiqua: direct influence of host plant dominates over the effects of individual condition
• On the susceptibility of different geographical races of the gypsy moth (Lymantria dispar L.; Lep., Lymantriidae) to a nuclear polyhedrosis virus of the rusty tussock moth (Orgyia antiqua Hbn.; Lep., Lymantriidae)1
• The genome sequence of the Vapourer moth, Orgyia antiqua (Linnaeus, 1758).