Opoptera aorsa Godart 1824
Creators: name: Penz, Carla M.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Nymphalidae
Opoptera
Opoptera aorsa

description: Opoptera aorsa (Godart, 1824)
(Fig. 1 D, 2D, 4D, 5D, 6D)
Type locality. Brazil [presumably Atlantic forest]
Diagnosis. Male FW length range 38.1–41.6 mm (based on specimens in Appendix 1). Although very similar to O. hilaris, it can be distinguished by the following characters. FW with a thin orange postmedial band that is disjointed at cell M3, and a reduced distal arm that forms a very thin line that usually reaches the white crescent spot in cell M1. Posterior portion of this band usually forming a smooth curve, in contrast to a ‘coarser’ shape in hilaris. A continuous transverse band is present across the center of the FW discal cell. HW submarginal band faded but noticeable. Similarly to hilaris, aorsa males lack a thin hairpencil inside HW discal cell, but have a conspicuously long, dark hairbrush adjacent to vein 1A+2A, plus a smaller hairbrush inside cell Cu2 below the scent-pocket. Females are paler than males, and have brighter and thicker orange bands. The male genitalia of aorsa and hilaris are similar, being highly divergent from other Opoptera (Fig. 4–5). The valvae are markedly thin, narrowed at base to produce a midline gap, and the sclerotized carena is elongated to form a solid, curved prong. In dorsal view, the uncus wings of aorsa are conspicuously broader than those of hilaris (compare Fig. 5 D and E). The female sterigma of aorsa and hilaris are markedly different (compare Fig. 6 D and E).
Distribution. Brazil, Atlantic forest (Testón & Corseuil 2002, Casagrande 2004, Appendix 1).
Remarks. Casagrande (2004) listed four subspecies; the nominal aorsa from Brazil, colombiana (Rothschild) from Colombia, fuscata Stichel from Brazil (Amazonas), and hilaris Stichel from Ecuador, which is treated below. I dissected males and females from Espírito Santo and Paraná, Brazil (Appendix 1), and the genitalia and wing pattern were consistent among the specimen series, but differed from specimens collected in other areas (see below).
Opoptera hilaris Stichel, 1901, NEW STATUS (Fig. 1 E, 1J, 2E, 4E, 5E, 6E)
Type locality. Ecuador.
Diagnosis. Male FW length range 38.3–42.5 mm (based on specimens in Appendix 1). Although very similar to O. aorsa, it can be distinguished by the following characters. FW with a thin orange postmedial band that is disjointed at cell M3, and a reduced distal arm that forms a very thin line that usually does not reach the white crescent spot in cell M1. Posterior portion of this band usually ‘coarse’, in contrast to a somewhat smooth curve in aorsa. The transverse band present across the center of the FW discal cell is composed of a series of contiguous small rounded segments (i.e., ‘broken’). HW submarginal band barely visible, contrasting the faded, but noticeable band seen in aorsa. Similarly to aorsa, males lack a thin hairpencil inside HW discal cell, but have a conspicuously long, dark hairbrush adjacent to vein 1A+2A, plus a smaller hairbrush inside cell Cu2 below the scent-pocket. Females are paler than males, have brighter and thicker orange bands, and faint blue iridescence. The male genitalia of hilaris and aorsa are similar, being highly divergent from other Opoptera (Fig. 4–5). The valvae are markedly thin, narrowed at base to produce a midline gap, and the sclerotized carena is elongated to form a solid, curved prong. This prong is slightly wider in hilaris than in aorsa, and the serrations are slightly larger and therefore more noticeable. In dorsal view, the uncus wings of hilaris are conspicuously narower than those of aorsa (compare Fig. 5 E and D). The female sterigma of hilaris and aorsa are markedly different (compare Fig. 6 E and D).
Distribution. Venezuela, Colombia, Ecuador, Peru, Bolivia, Paraguay, western Brazil (Amazon forest to Mato Grosso) (D’Abrera 1987, Casagrande 2004, A. Neild pers. comm., Appendix 1).
Justification for new status. In his original description Stichel (1901) identified two key characters that separated Ecuadorean O. aorsa hilaris from nominal aorsa from Eastern Brazil: ventral FW discal cell with a broken transverse band, and dorsal HW solid brown (i.e., lacking the orange submarginal band present in aorsa). Neither the original nor subsequent descriptions (e.g., Stichel 1902) mentioned genitalia, and I thus assume that Stichel did not dissect hilaris. I examined and dissected males from Ecuador, Peru, Bolivia and Brazil (Amazonas; Appendix 1). Although there is slight variation among these specimens, they can be consistently recognized as hilaris by the characters given here, including genitalia (Fig. 1 E, 2E, 5E, 6E). The remarkable divergence in the female sterigma (Fig. 6 E) provides strong support for the separation of these two taxa. Opoptera aorsa ocurrs in the Brazilian Atlantic forest, while O. hilaris seems to be more widespread across the Amazonian region and western side of South America. It is unknown to me whether these species occur in sympatry.
New combinations. The descriptions of the subspecies fuscata (Stichel 1908; Brazil, Amazonas, examined here) and colombiana (Rothshild 1916; Colombia, not available for examination) are consistent with the diagnostic characters of hilaris. Therefore, two new combinations are proposed: O. hilaris fuscata, NEW COMBINATION and O. hilaris colombiana, NEW COMBINATION.
description: Published as part of Penz, Carla M., 2009, The phylogeny of Opoptera butterflies, and an assessment of the systematic position of O. staudingeri (Lepidoptera, Nymphalidae), pp. 1-20 in Zootaxa 1985 on pages 11-12, DOI: 10.5281/zenodo.185409