Brontostoma colossus (Distant, 1902)

Figs. 1E, F

Distribution: This species was originally described from Paraguay (Distant 1902), and additionally recorded from Argentina, Bolivia, and Brazil (Dougherty 1995; Maldonado 1990; Wygodzinsky 1951). It is a new record from Colombia and Ecuador.

Remarks: Wygodzinsky (1951) indicated the highly variable color pattern of this species, not only across its known distributional range, but also within a single locality. Nonetheless, the yellowish longitudinal markings on the corium, usually with transverse ones connecting the longitudinal ones, is indicative of this species. One aspect of the examined specimen not agreeing with the short notes of Wygodzinsky (1951) is that the all the specimens examined by him—mostly from Argentina —had a uniformly darkened forewing membrane. In the examined specimen here (Fig. 1E), as well as one specimen from Ecuador (from iNaturalist, see below), the membrane is variegated with pale brown markings. Other specimens of B. colossus from the northern portion of its distribution (e.g., French Guiana: https://www.inaturalist.org/observations/178448936; Brazil, [Amazonas]: https://www.inaturalist.org/ observations/178448936, [Pará]: https://www.inaturalist.org/observations/143728928, [Mato Grosso]: https://www. inaturalist.org/observations/143569846), have the membrane with a few pale brown small and localized areas, in contrast to the strongly variegated brown areas of the specimens from Colombia and Ecuador. We interpret this as intraspecific variation of the northern populations of B. colossus. Clearly, better collecting efforts in these areas, and study of the male genitalia, will help elucidate the variation and limits of this species.

Examined material: COLOMBIA. Guaviare: 1 ♀, San Jose del Guaviare, playa Güio [02.5722°N 72.7090°W, 180 m], x.2013, E. Flórez y estudiantes de Taxonomia Animal, ICN103360 (ICN). ECUADOR. Napo: adult, sex unknown, Wild Sumaco Lodge, 0.675693°N 77.601286°W, Emily Hjalmarson, https://www.inaturalist.org/ observations/149450579.