Manduca sexta

Larvae distinguished from the closely related tomato hornworm (Manduca quinquemaculata) by seven white diagonal lines with black borders (versus eight V-shaped white markings without borders) and red-tipped horn (versus dark blue or black horn). Adults can be separated from M. quinquemaculata by hindwing pattern and geographic overlap. First instar larvae possess a tubular silk-producing spigot and well-developed Lyonet's glands, which are lost in later instars—a unique developmental trajectory among sphingids.

Agricultural and natural areas supporting host plants in family Solanaceae; larvae prefer humid microenvironments and will actively seek water sources when dehydrated. Adults frequent flowering plants for nectar.

Widespread through much of the Americas: North America, Central America, South America, and Caribbean. Multiple subspecies recognized including M. s. sexta (North and Central America), M. s. caestri (Chile), M. s. jamaicensis (Caribbean), M. s. leucoptera (Galápagos Islands), M. s. paphus (South America), M. s. saliensis (Argentina), and M. s. garapa (Saipan). Natural populations show genetic differentiation across the United States, with Arizona populations particularly distinct.

Two generations per year in most areas; three to four generations possible in Florida. Larvae most abundant in midsummer with possible secondary peak in late summer. Winter passed in pupal stage. Total life cycle 30–50 days under favorable conditions.

Larvae are facultative specialists preferring Solanaceae, principally tobacco (Nicotiana), tomato (Solanum lycopersicum), and Datura species; can develop on alternative hosts but with reduced growth rates. Larvae use lateral and medial sensilla styloconia on mouthparts to identify solanaceous plants via detection of indioside D, a steroidal glycoside. Adults are nectarivorous, feeding on flowers while hovering.

• Nicotiana - primary host plantlarvae sequester nicotine as defense
• Solanum lycopersicum - primary host plantcommonly known as tomato
• Datura - primary host plantincludes jimsonweed
• Capsicum - host plantpepper
• Solanum melongena - host planteggplant
• Solanum tuberosum - host plantpotato
• Cotesia congregata - parasitoidbraconid wasp that lays eggs in larvae; parasitizes 31–57% of field populations
• Polistes erythrocephalus - predatorpaper wasp that feeds on larvae

Complete metamorphosis with five larval instars separated by ecdysis; additional instars may occur under poor nutrient conditions. Final instar larvae enter "wandering" phase to seek pupation site, then burrow underground to pupate. Pre-pupa stage involves considerable shrinkage. Adults eclose from pupal case; females mate once, males multiple times. Mating occurs on vertical surfaces at night with pairs in opposite-facing position.

Larvae exhibit "wandering" behavior before pupation, leaving host plants to burrow underground. When attacked, larvae emit clicking sounds (5–50 kHz) from mandibles as acoustic aposematism, followed by thrashing and biting. Larvae demonstrate humidity-seeking behavior using antennae to locate water. Adults are strong fliers capable of sustained hovering while feeding. Spatial odor discrimination between antennae (>70% accuracy) enables tracking of turbulent odor plumes.

Significant herbivore in agricultural ecosystems; serves as host for parasitoid wasps contributing to biological control dynamics. Larvae bioaccumulate plant secondary compounds, influencing tri-trophic interactions. Adults may contribute to pollination while nectaring.

Major agricultural pest of tobacco, tomato, and other solanaceous crops; larvae cause defoliation and fruit damage. Widely used as model organism in neurobiology, developmental biology, immunology, and medical imaging research due to large size and accessible anatomy. Genome sequenced and publicly available. Commercially reared as food for captive insectivorous animals. Subject of extensive biological control efforts using Cotesia congregata.

• Manduca quinquemaculataLarvae nearly identical but distinguished by eight V-shaped white markings without borders (versus seven diagonal lines with black borders) and dark blue or black horn (versus red); adults separable by hindwing pattern
• Manduca rusticaOverlapping distribution and similar adult morphology; larvae have different host plant preferences and patterning

The common name "tobacco hornworm" is often applied indiscriminately to both M. sexta and M. quinquemaculata larvae found on tomatoes. The white cocoons of Cotesia congregata on parasitized hornworms are frequently mistaken for large eggs rather than emergent wasp pupae. The pre-pupal stage, during which larvae shrink considerably, is often misidentified as a dead or dying caterpillar.

• model organism
• agricultural pest
• chemical defense
• nicotine sequestration
• parasitoid host
• silk loss
• neurobiology
• genome sequenced

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• The Hornworms Are Not Your Friends | Bug Squad
• National Moth Week Ended But... | Bug Squad
• Insect FAQs | Entomology Research Museum
• News Flash: Don't Miss 'Current Techniques in Morphology' | Bug Squad
• Advanced Morphology Techniques Reveal Tobacco Hornworm's Secrets
• Scientists Sequence the Genome of the Tobacco Hornworm
• Discovery of a Manduca sexta Allatotropin Antagonist from a Manduca sexta Allatotropin Receptor Homology Model
• Spatial odor discrimination in hawkmoth, Manduca sexta (L.)
• Linking brain activity to odor-guided behavior inManduca sexta
• Population differentiation and structural variation in the Manduca sexta genome across the United States
• Manduca sexta experience high parasitoid pressures in the field but minor fitness costs of consuming plant secondary compounds