Hydririni

Distinguished from other Spilomelinae tribes by two synapomorphies: (1) female genitalia with appendix bursae on corpus bursae, and (2) male genitalia with hair scale patches on central anterior edge of abdominal sternite 8. Distinguished from the 'euspilomeline' clade by plesiomorphic characters: absence of longitudinal sclerotized strip on pleural membranes of male abdominal segment 8, straight or concave costa of valves, and evenly sclerotized phallus apodeme in male genitalia. Female signa either 'ediacaroid' (elongate, zipper-shaped to nearly circular with reduced transverse axis) or circular with radiating spines; Ommatospila possesses both types. Genera Choristostigma, Hydriris, Nehydriris and Rhectothyris share additional male genitalic features: lobar processes with hair-pencil fields and phallus with long caecum.

Tropical and subtropical environments, predominantly in Central and South America. Specific microhabitat preferences are poorly documented.

Primarily Neotropical, with majority of species described from tropical Central and South America. The genus Lamprosema contains many Old World species that are taxonomically misplaced in this tribe.

Larvae predominantly feed on Sapindaceae: recorded hosts include Allophylus psilospermus, A. racemosus, Paullinia bracteosa, P. costaricensis, P. faginea, P. fuscescens, P. grandifolia, P. turbacensis, Serjania atrolineata, S. mexicana, S. rhombea, S. schiedeana, S. valerioi, and Urvilea ulmacea. Hydriris ornatalis larvae feed on Ipomoea batatas (Convolvulaceae) and related plants—young larvae on leaf undersides, older instars skeletonizing leaves. A single record of Lamprosema feeding on Senna obtusifolia (Fabaceae) from Costa Rica.

• Allophylus psilospermus - larval food plantSapindaceae
• Allophylus racemosus - larval food plantSapindaceae
• Paullinia bracteosa - larval food plantSapindaceae
• Paullinia costaricensis - larval food plantSapindaceae
• Paullinia faginea - larval food plantSapindaceae
• Paullinia fuscescens - larval food plantSapindaceae
• Paullinia grandifolia - larval food plantSapindaceae
• Paullinia turbacensis - larval food plantSapindaceae
• Serjania atrolineata - larval food plantSapindaceae
• Serjania mexicana - larval food plantSapindaceae
• Serjania rhombea - larval food plantSapindaceae
• Serjania schiedeana - larval food plantSapindaceae
• Serjania valerioi - larval food plantSapindaceae
• Urvilea ulmacea - larval food plantSapindaceae
• Senna obtusifolia - larval food plantFabaceae; single Costa Rican record for Lamprosema
• Ipomoea batatas - larval food plantConvolvulaceae; Hydriris ornatalis

Complete metamorphosis (egg, larva, pupa, adult). Larval morphology and chaetotaxy have not been scientifically described. In Hydriris ornatalis, young larvae feed on leaf undersides while older instars skeletonize leaves.

Larvae of Hydriris ornatalis exhibit age-related feeding behavior shift: young larvae feed on leaf undersides, older instars skeletonize leaves.

Larvae function as herbivores, predominantly on Sapindaceae. Role in food webs and ecosystem processes otherwise undocumented.

Hydriris ornatalis larvae feed on sweet potato (Ipomoea batatas), indicating potential agricultural relevance. No other documented economic or cultural significance.

• Other Spilomelinae tribesHydririni distinguished by appendix bursae in females and hair scale patches on male sternite 8; 'euspilomelines' lack these plesiomorphic traits and possess derived characters including longitudinal sclerotized strip on male abdominal segment 8 pleural membranes
• PyraustinaeShares plesiomorphic characters with Hydririni (appendix bursae, ediacaroid signum) but is sister group to Spilomelinae rather than nested within it; precise distinction requires phylogenetic analysis

• Crambidae
• Spilomelinae
• Lepidoptera
• Neotropical
• Sapindaceae
• genitalic morphology
• systematics
• phylogenetics
• herbivory
• agricultural pest potential

• BugGuide
• Wikipedia
• iNaturalist taxon