El género Leptonema (Trichoptera: Hydropsychidae) en Costa Rica, con la descripción de una nueva especie

Abstract

El género Leptonema Guérin 1943 (Hydropsychidae: Macronematinae) es uno de los géneros de Trichoptera más abundantes y más ampliamente distribuidos en el Nuevo Mundo. En Costa Rica son conocidas 24 especies. El presente trabajo incluye la descripción e ilustración del genital del macho de una especie no descrita para Costa Rica: Leptonema tica. Además de la descripción diagnóstica y ilustración de la larva, se incorporan las descripciones diagnósticas e ilustraciones del phallus de los machos de las otras 24 especies. Anotaciones de la historia natural del adulto y la larva del género son incluidas. Finalmente, se incluyen una clave de identificación en inglés y español de las especies conocidas de Leptonema para Costa Rica y se ilustran sus registros de distribución en Costa Rica.

Translated abstract

The genus Leptonema Guérin 1843 (Trichoptera: Hydropsychidae: Macronematinae) is one of the best known and most easily recognized of the Neotropical caddisflies. In the New World, the genus is widely distributed from southern North America through Central and South America, including the Antilles, but excluding souther Chile and adjacent Argentina. The adults of Leptonema are large (10-40 mm) with light brown to light green translucent wings. Some species have small black or dark spots or patterns on the forewings. Larvae of Leptonema build refuges with small silken nets, and this way feed by filtering fine organic particles from the water. The refuges and nets are built with small gravel, sand, and silk. In 1914, Banks reported L. albovirens from Costa Rica, the first record of the genus for Costa Rica. In 1987, Flint et al. provided an exhaustive taxonomic review of the world species, and recognized 15 species groups, five of which were present in Costa Rica. In addition, they described 48 new species, four from Costa Rica, and reported five additional records. Holzenthal added six additional species records, and Muñoz-Q. described five new species, of these L. tapanti is the first species in the stigmosum Group defined by Flint et al. and present in the country. In total, 24 species of Leptonema have been previously recorded in Costa Rica. For this research, collections of Leptonema specimens in the University of Minnesota Insect Collection, St. Paul, MN and the National Museum of Natural History, Smithsonian Institution, Washington, DC. were examined. In this paper, one additional undescribed species from Costa Rica is diagnosed, described and illustrated: Leptonema tica. Diagnoses and illustrations of the male genitalia of the other species are presented. Figures of the larva and adult, as well as aspects of natural history of the genus are included. Finally, an identification key in English and Spanish is provided, together with distribution record maps of all species in Costa Rica are included.