Hemileucinae

Distinguished from other Saturniidae subfamilies by the combination of: (1) presence of urticating spines or setae in larvae, (2) New World distribution (North and South America only), and (3) adults with reduced mouthparts. Within Saturniidae, differs from Saturniinae (giant silk moths) by generally smaller size and different larval spine morphology; from Cercophaninae by geographic restriction to the Americas. Genus-level identification relies on wing pattern, genitalia morphology, and larval characteristics.

Diverse habitats across the Americas including tropical and subtropical forests, montane grasslands, and temperate woodlands. Specific habitat associations vary by genus; some species show affinity for particular host plant communities such as pine forests (Hispaniodirphia) or grasslands (Leucanella).

Endemic to North and South America; approximately 630 species distributed across the continents. Notable regional endemics include Hispaniodirphia in the Greater Antilles (only saturniid genus documented from this region).

Varies by species and latitude. Some species exhibit facultative pupal diapause enabling bivoltine or multivoltine life cycles under favorable conditions (e.g., Dirphia dolosa in southern Brazil). Tropical species may breed continuously.

• Ligustrum ovalifolium - laboratory food plantAccepted by Lonomia electra in captivity
• Psidium guajava - laboratory food plantAccepted by Hylesia metapyrrha; natural host unknown
• Schizolobium parahyba - natural host plantNatural host of Automeris jucunda in Colombia
• Rubus fruticosus - laboratory food plantReplacement food plant for Automeris jucunda
• Diospyros khaki - laboratory food plantAccepted by Periga circumstans; prolonged larval development compared to alternative host
• Ilex paraguariensis - laboratory food plantAccepted by Periga circumstans
• Anacardium occidentale - host plantNatural host of Dirphia moderata; species considered potential defoliator pest of cashew
• Pennisetum clandestinum - host plantExotic grass used by Meroleuca (Meroleucoides) dargei in Colombia
• Solanum lycocarpum - host plantHost plant of Leucanella memusae in Brazilian mountain grasslands
• Pinus - supposed host associationCaterpillars of Hispaniodirphia spp. suspected to associate with pine trees; unconfirmed

Complete metamorphosis with variable development times. Egg stage: 15–52 days depending on species and conditions. Larval stage: 5–7 instars, duration 6–12+ weeks; larvae are gregarious in many species. Pre-pupal stage: approximately 8–9 days. Pupal stage: 50–60 days; females often larger and longer-developing than males. Adult stage: short-lived, 5–6 days average, non-feeding. Total development from egg to adult: approximately 120–191 days under laboratory conditions.

Larvae of many species exhibit gregarious behavior, traveling and feeding in groups (documented in Lonomia electra, Hylesia metapyrrha, Automeris jucunda, Dirphia dolosa). This social behavior increases risk of severe envenomation when humans contact large congregations. Adult females of some genera (e.g., Hylesia) possess easily detachable urticating abdominal hairs.

Larvae function as herbivores; some species are potential defoliator pests of economically important crops (e.g., Dirphia moderata on cashew). Medical importance due to venomous larvae creates human-wildlife conflict in affected regions.

Medical significance due to larval envenomation. Lonomia caterpillars cause severe accidents: L. obliqua and L. achelous produce hemotoxins causing disseminated intravascular coagulation and hemorrhagic disease, potentially fatal. Other species cause erucism (skin irritation from urticating setae). Adult females of Hylesia cause lepidopterism (allergic reactions from airborne scales/hairs). Venom toxins have potential medical applications as anticoagulants.

• SaturniinaeAlso in Saturniidae but distinguished by generally larger size, different larval morphology, and cosmopolitan distribution including Old World
• CercophaninaeAlso in Saturniidae but restricted to southern South America and Australia; lacks the characteristic larval urticating spines of Hemileucinae
• ArsenurinaeNeotropical Saturniidae subfamily with large size but different wing venation and larval characteristics

• urticating spines
• venomous caterpillars
• medical entomology
• envenomation
• gregarious larvae
• New World endemic
• Saturniidae
• Lepidoptera
• erucism
• lepidopterism

• BugGuide
• Wikipedia
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• Up Close and Personal With Venomous Moths
• Biological aspects of Hylesia metapyrrha (Lepidoptera; Saturniidae; Hemileucinae), in laboratory
• Hispaniodirphia lemaireiana n. sp., a new saturniid from the Greater Antilles (Lepidoptera: Saturniidae, Hemileucinae)
• Biology of Automeris jucunda (Lepidoptera: Saturniidae, Hemileucinae) with taxonomic notes on A. hamata subgroup
• Un caso de braquipterismo y observaciones en meroleuca (meroleucoides) dargei lemaire, 1982 (lepidoptera: saturniidae: hemileucinae)
• Aspects of the biology and morphology of Dirphia dolosa Bouvier, 1929 (Lepidoptera: Saturniidae: Hemileucinae)
• Biology and External Morphology of the Immature Stages of Dirphia moderata Bouvier (Lepidoptera: Saturniidae: Hemileucinae) in Anacardium occidentale L.
• Biological aspects of Periga circumstans Walker, 1855 (Lepidoptera: Saturniidae: Hemileucinae) with larvae reared on khaki and mate-plant leaves
• Solanum lycocarpum Saint Hilaire (Solanaceae) is Host Plant of Leucanella memusae (Walker) (Lepidoptera: Saturniidae: Hemileucinae) in Brazilian Mountain Grasslands