First report of the family Micropterigidae (Lepidoptera) from Central America with descriptions of two new genera and five new species

We describe five new micropterigid species representing three genera (Magnijuxta n. gen. and Sporaphaga n. gen., and Squamicornia Kristensen and Nielsen) of the Sabatinca group from Costa Rica’s Atlantic slope: Magnijuxta purpuravena n. sp., M. nishidai n. sp., M. watkinsi n. sp., Sporaphaga costaricensis n. sp., and S. purpuraguttata n. sp.). Adults were collected in the vicinity of sporulating fronds of seven fern genera:  Dicksonia, Diplazium, Lomariopsis, Megalastrum, Olfersia, Polybotrya, and Sticherus.  Adults often occurred in mixed-species swarms, containing dozens to more than 200 individuals, in and around spore-producing fern fronds, especially those of a Olfersia at La Selva Biological Station at 60 m (a low-elevation Caribbean rainforest), a Stichterus at 1500 m, and a Megalstrum at 2000 m. Adults used fertile fronds at the peak of spore release as mating and feeding stations. Sex ratios were strongly male biased. No larvae were located; nor were liverworts found in the vicinity of the swarms. Males of Magnijuxta bear highly derived sexual characters: both the juxta and valva are hypertrophied; they possess unique (pre-anal) valvoid lobes roughly in the position of the gnathos or socii of other Lepidoptera, which have no known homologue in Lepidoptera; and bear external androconial tufts that extend across exposed portions of the valvae. Males and females of all five species are figured, described, and a key to adults is provided.