by Steven J. Cary
The Brushfoots (Nymphalidae). This family is our second richest in terms of number of species and perhaps the most variable in terms of sizes, colors, patterns and behaviors. Despite the obvious differences in wing morphology, members all share a unifying structural character: on adults, the forelegs are reduced to tiny, brush-like structures, leaving only four functional legs. Many of our most familiar butterflies are members of this family. Pursuant to Pelham’s (2019) catalog, we have ~100 species in ten subfamilies.
Tropical Brushfoots (Nymphalidae: Biblidinae). This subfamily is tropical and subtropical in composition and contributes only four strays to our butterfly fauna. Of those, only the Common Mestra is seen here with any regularity. Membership in this group is under debate among taxonomists. There is no doubt that other butterfly species in this family have wandered to New Mexico or will do so in the future. It is a large family with many species. In fact, several other Biblidine species have been anecdotally reported from our state, but without substantiating data. The discussion below addresses those species for which a date, location and observer are confidently known. Photos are needed.
- Dingy Purplewing (Eunica monima)
- Blackened Bluewing (Myscelia cyananthe)
- Gray Cracker (Hamadryas februa)
- Common Mestra (Mestra amymone)
Eunica monima (Stoll) Dingy Purplewing
Dingy Purplewing is native to Central America, the Caribbean and south Florida. It occurs in our area rarely as an accidental stray. In its tropical habitat, larvae are herbivorores on Zanthoxylum pentamon, a member of the citrus family (Rutaceae). Dingy Purplewings produce continuous generations in their tropical home. Individuals turn up in our area preferentially in late summer, coinciding with southerly air flow during the monsoon season. Our solitary report came from Cloverdale (Hidalgo County), on 1 August 1986 (Kilian Roever). Adults will feed at flowers, tree sap, excrement and moist earth.
Myscelia cyananthe (C. Felder & R. Felder) Blackened Bluewing
All the Myscelia species are tropical and subtropical. The nearest breeding areas for the Blackened Bluewing are the Atlantic and Pacific coasts of Mexico, including much of Sonora. Myscelia cyananthe flies and breeds year-round in the tropics. Occasional strays are reported from Texas, New Mexico and Arizona, usually in late summer and autumn. Our single record is from 12 May 1902, when an individual was captured in Dry Canyon near Alamogordo at the base of the Sacramento Mountains (Otero County) by Henry L. Viereck (Skinner 1902c).
Hamadryas februa (Hübner) Gray Cracker
The various crackers (Hamadryas species) are a subtropical group distributed northward from Argentina, reaching North America only infrequently and by accident. They inhabit Lower Sonoran Zone woodlands. Euphorbiaceae (e.g., Dalechampia species, Tragia species) are larval hosts, but there is no evidence of breeding in New Mexico. Gray Cracker is multivoltine farther south. Our one report is dated 19 July 1990, from Clanton Draw, Peloncillo Mountains (Hidalgo Cocunty) by Kilian Roever, suggesting occasional penetration into New Mexico during the summer monsoon. Males perch head-down on tree trunks with wings laid flat, then dart out at passing butterflies while making a cracking sound with specialized abdominal structures. Presumably the sound warns away competing males and attracts females. The several Hamadryas species can be difficult to tell apart. Hamadryas februa and Hamadryas glauconome, both reported from southeast Arizona (Bailowitz and Brock 1991), are particularly challenging.
Mestra amymone (Ménétriés) Common Mestra (updated January 13, 2021)
Description. Mestra is of modest size, rather pale and rounded. The ventrum is apricot in color with bands of white spots. The upperside is white with gray patches. Black vein-ends give the wing margin a scalloped appearance. Range and Habitat. Mestra amymone lives from Central America northward along both Mexican coasts as far as south Texas. Adults stray northward in summer, singly or in groups, into the Great Plains. It strays somewhat regularly to southeast New Mexico (counties: Ch,Cu,DA,Ed,Gr,Hi,Le,Ot,Qu,Ro,So,Un). Life History. Larvae eat plants in Euphorbiaceae family. Dalechampia scandens, Tragia volubilis and Tragia neptifolia are used elsewhere; Tragia ramosa is the likely host in our state. There is no evidence of reproduction in New Mexico, but a late season generation is quite conceivable. Flight. Our records of Mestra fall between August 9 and November 5, on the heels of the summer thunderstorm season. In New Mexico, look for it in moist, shady oases where it flies delicately near the ground and siphons nectar from flowers. Comments. The first two New Mexico specimens of Mestra amymone are in the Carnegie Museum collection, captured in the Magdalena Mountains (So) in August 1894 by H. Kahl, a member of F. H. Snow’s final New Mexico collecting expedition. As with many subtropical strays, years may elapse during which none are seen, but when conditions are particularly favorable in its breeding range, it may enter our state in surprising numbers.