Portentomorphini

Distinguished from other Pyraustinae by unique male genitalia: costa detached and projecting freely dorsally with setose apex, reduced valva with large sacculus, and presence of curved fibula. Female genitalia with appendix bursae and variable signum structure. External appearance of yellow forewings with red/orange postmedial area is suggestive but not diagnostic without genital examination.

Adults are relatively small moths with forewing length 7.5–9.5 mm (wingspan 20–29 mm). Forewings typically yellow with distinct red or orange postmedial (outer) area. Male genitalia unique among Pyraustinae: costa detached from valva and projecting freely dorsally with setose apex; valva reduced to large membranous sacculus extending outward with setose terminal field; thin elongate often articulated curved fibula emerging from dorsal valva edge. Female genitalia with membranous appendix bursae at anterior end of ductus bursae (laterally attached to corpus bursae in Pioneabathra); signum shape variable—four-armed star in Hyalobathra and Cryptosara, elongate ovoid in Portentomorpha, two large opposing granulose areas in Pioneabathra and Isocentris filalis.

Tropical and subtropical regions; one species (Hyalobathra intermedialis) recorded from montane habitat at 1,700 m elevation in Qin Mountains, China.

Tropics and subtropics of Australia, Africa, Asia, South America, and Central America. Montane exception in Central China (Shaanxi province).

Caterpillars primarily feed on Phyllanthaceae: Margaritaria nobilis (Portentomorpha xanthialis), Glochidion and Phyllanthus (Hyalobathra), Flueggea (Pioneabathra olesialis, Isocentris filalis), Phyllanthus urinaria (Mabra eryxalis). Additional recorded hosts: Euphorbia virosa (Euphorbiaceae), Sphaeranthus indicus (Asteraceae), Abrus precatorius (Fabaceae), Helianthus annuus (Asteraceae), Solanum (Solanaceae), and rice (Poaceae).

• Margaritaria nobilis - food plantPortentomorpha xanthialis
• Glochidion - food plantHyalobathra species
• Phyllanthus - food plantHyalobathra species, Mabra eryxalis
• Flueggea - food plantPioneabathra olesialis, Isocentris filalis
• Euphorbia virosa - food plantIsocentris
• Sphaeranthus indicus - food plantIsocentris
• Abrus precatorius - food plantHyalobathra
• Helianthus annuus - food plantHyalobathra
• Solanum - food plantPioneabathra olesialis
• Oryza sativa - food plantMabra eryxalis

Mabra eryxalis has been recorded feeding on rice, indicating potential agricultural relevance.

• PyraustiniPortentomorphini has been found nested within Pyraustini in some phylogenetic studies, rendering Pyraustini paraphyletic; distinguished by the unique genital synapomorphies of Portentomorphini
• Other Pyraustinae tribesLack the distinctive male genitalia with detached costa, reduced valva with large sacculus, and curved fibula characteristic of Portentomorphini

Long treated as a synonym of Pyraustinae due to lack of phylogenetic study; reinstated as valid tribe in 2019, though 2022 study suggests it may render Pyraustini paraphyletic.

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