Butterflies of New Mexico: The Brushfoots I: Snouts (Nymphalidae: Libytheinae)

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 distributed as shown below. Other works may arrange, lump, or divide families in other ways.

  • Libytheinae: Snout Butterflies (1),
  • Danainae: Milkweed Butterfllies (3),
  • Heliconiinae:Fritillaries and Longwings (17),
  • Limenitidinae: Admirals and Sisters (4),
  • Apaturinae: Emperors (4),
  • Biblidinae: Tropical Brushfoots (3 or 4?),
  • Cyrestinae: Daggerwings (1),
  • Nymphalinae: True Brushfoots (48?),
  • Charaxinae: Leafwings (2), and
  • Satyrinae: Satyrs (17).

Snouts (Libytheinae). Does it seem silly to erect an entire subfamily to house one (okay, two) species? I suppose the Snouts must be just that different. There is one species of snout butterfly in North America, a second in the Caribbean.

  • American Snout (Libytheana carinenta)

Libytheana carinenta (Cramer)              American Snout (updated January 8, 2021)

Description. This, the only member of this subfamily found regularly in the US, is easily identified by the elongated palpi (the “snout”) and the notch in the outer forewing margin. Libytheana carinenta has orange patches on dark wings, with white spots near the dorsal forewing apex. The underside is iridescent gray when freshly emerged, aging to mottled, camouflaged gray. The combination of wing shape and ventral colors mimics a dried leaf when perched on a twig with wings closed; the snout serves as the leaf “petiole.” Range and Habitat. Libytheana carinenta is most common in Mexico and the southern US, including southern New Mexico (counties: Be,Ca,Ch,Ci,Co,DA,Ed,Gr,Gu,Hi,Le,Li,LA,Lu,MK,Mo,Ot,Ro,SJ,SF,Ta,To). It lives in Upper Sonoran Zone riparian habitats where the larval hosts thrive. This species is strongly migratory, often penetrating far north during late summer and fall, but with no return flight in autumn. Life History. Larvae eat foliage of hackberry trees (Ulmaceae). In our area Snouts use Celtis reticulata and Celtis pallida, scrubby trees that grow in riparian canyons and arroyos in southern and eastern New Mexico. Flight. New Mexico records fall between January 19 and December 5. Usually the Snout must reinvade New Mexico each year from farther south, after which it may produce up to two warm season broods. Individuals flying in early spring may have overwintered here. Peak numbers are in July to October. Adults come to riparian nectar (e.g., Baccharis). Comments. Other guides may present this butterfly as Libytheana bachmannii Kirtland, but that name no longer applies. Our Snouts belong to subspecies Libytheana carinenta larvata (Strecker). J. D. Eff reported “thousands” in Belen (Va) from 29 June to 15 July 1950.

American Snout (Libytheana carinenta larvata) north of Dexter, Chaves Co. NM; October 9, 1994 (photo by Steve Cary).
American Snout (Libytheana carinenta larvata) Silver City, Grant Co., NM; October 6, 2017 (photo by Steve Cary).
American Snout (Libytheana carinenta larvata) Wild Rivers Recreation Area, Rio Grande del Norte National Monument, Taos Co., NM; September 8, 2016 (photo by Steve Cary).