Aegiale hesperiaris (Walker, 1856)

Sapkota, Sajan Kc Anisha, 2024, First record of the Mexican-M hairstreak Parrhasius moctezuma (Clench, 1971) (Lepidoptera: Lycaenidae) in Texas, USA, and possible sighting of the tequila giant skipper Aegiale hesperiaris (Walker, 1856) (Lepidoptera: Hesperiidae), Insecta Mundi 2024 (84), pp. 1-6 : 4-5

Aegiale hesperiaris (Walker, 1856)

Material examined. Observation (no photograph or specimen). 1, sex unknown, USA, National Butterfly Center, Mission, Hidalgo County, Texas (26.179889, -98.366167, 35 m), 04-XII-2022.

Diagnosis. Aegiale is a monotypic genus, but it resembles most species of Agathymus H. Freeman, 1959 ( Hesperiidae ), with which it is sympatric in parts of Mexico. Morphologically, Aegiale hesperiaris is characterized by its distinctive white antennae bearing apiculi, that extend to or beyond the forewing cell ( Freeman 1969); the overall size is generally larger than that of Agathymus ; the dorsal fore- and hindwings showcase broad orange patches, providing a notable contrast against the dark background ( Fig. 3a ), whereas the ventral hindwing surface features grey overscaling with dark-lined, muted spots ( Fig. 3b ; see Warren et al. 2024).

Remarks. On the given date and location, at approximately 3:00 pm CT, a potential individual of Aegiale hesperiaris was observed perched on a Duranta erecta L. ( Verbenaceae ) twig with its wings half-open and dorsal orange bands well-visible; it possessed white antennae. The sighting was made by the first author, who was alone in the area. Unfortunately, the individual flew away when the author attempted to take a photo, leaving no visual record. Later discussions with butterfly enthusiasts at the National Butterfly Center suggested possible identifications as Megathymus yuccae (Boisduval and Le Conte, [1837]) ( Hesperiidae ) or Stallingsia maculosus (H. Freeman, 1955) ( Hesperiidae ), but neither of these species has broad orange patches on their dorsal wings. The author recalls the butterfly with wings as long as those of a “giant grasshopper”, orange patches on the dorsal side, and white antennae. It was not until sharing the anecdote with Jeffrey Glassberg (pers. comm. 2023) six months later that the possibility of A. hesperiaris was proposed. Although adults are reported from April to May ( Jaimes-Rodríguez et al. 2020) and August to November ( Freeman 1969) in Mexico, there are two observations from December on iNaturalist (2024). Following a thorough examination of online specimens and those at the MGCL, the author is confident in the identification, although regretful that a photograph was not obtained, which would have represented the first documented record of this species in the US. Owing to the lack of photographic evidence or a specimen, this sighting will remain unconfirmed; however, there remains a possibility of rediscovery in the vicinity of the study area or elsewhere in south Texas, as species of the subtribe Megathymina are known to be non-migratory and are often found near their host plants ( Freeman 1967, 1969; Quinn 2020). Additionally, Bordelon and Knudson (2006) reported a potential sight record of A. hesperiaris near Sinton, Texas, suggesting that the species may be sporadically present in south Texas or occasionally introduced through plant imports from Mexico, a possibility that cannot be ruled out. Given the species’ typical habitat at higher elevations (usually above 1200 m), the likelihood of a sustainable population establishing itself in south Texas is, however, low (Andrew Warren pers. comm. 2024).

Distribution. In addition to the preliminary evidence presented here suggesting a Texas distribution, this species is found in arid regions of the Mexican Altiplano south to Oaxaca (see Warren et al. 2024).

Figures

Figure 3. Spread specimen of Aegiale hesperiaris (Walker, 1856) from Mexico, currently deposited in the MGCL. a) Dorsal view. b) Same specimen, ventral view.