Arcas Swainson, 1832

Martins, Ananda Regina P., Duarte, Marcelo & Robbins, Robert K., 2019, Phylogenetic Classification of the Atlides Section of the Eumaeini (Lepidoptera, Lycaenidae), Zootaxa 4563 (1), pp. 119-134 : 125-126

Arcas Swainson, 1832

Type species: Papilio imperialis Cramer

The species currently placed in Arcas have been recognized as a distinct and widespread Neotropical group for more than a century ( Godman & Salvin 1887 –1901; Draudt 1919 –1920). Nicolay (1971) first revised the genus, recognizing seven species. In the ensuing decades, other names were proposed, leading to the phylogenetic revision in Robbins et al. (2012) and the recognition of nine species.

The study of Martins et al. (2018) identified ten synapomorphies for Arcas ( Table 1, Fig. 8), but the emerald green ventral wings, long hindwing tails, and deep anal lobe cleft are conspicuous characterizing traits ( Fig. 2 and 9 ). The genus can also be recognized by its male and female genitalic structures.

The phylogenetic results in Martins et al. (2018) differ from those in Robbins et al. (2012) in the position where the genus is rooted. The grouping A. splendor + A. alleluia + A. gozmanyi was a monophyletic lineage previously, but because of the changed rooting, is now a paraphyletic group.

Arcas imperialis (Cramer, 1775) (Papilio) , type locality: Surinam

actaeon (Fabricius, 1775) ( Papilio ), type locality:?, suppr. (ICZN, Op. 1058)

venus (Fabricius, 1781) ( Papilio ), type locality: Surinam, repl. name

oakesii (Butler, 1884) ( Theritas ), type locality: Colombia

magnifica Austin & K. Johnson, 1995, type locality: Brazil (RO)

Distribution and Habitat. Mexico to Argentina and southern Brazil in wet lowland forest up to about 1,000 m elevation.

Arcas ducalis (Westwood, [1851] ( Thecla ), type locality: Brazil

Distribution and Habitat. Brazil from RJ to RS in wet lower montane forest in the north and at lower elevations in the south.

Arcas cypria (Geyer, 1837) (Theritas) , type locality: Mexico (YUC)

paphia (C. Felder & R. Felder, 1865) ( Pseudolycaena ), type locality: Colombia

publica (Röber, 1923) ( Thecla ), type locality: Colombia

Distribution and Habitat. Mexico to Venezuela and Colombia in wet lowland forest.

Arcas jivaro Nicolay, 1971 , type locality: Ecuador

Distribution and Habitat. Ecuador to Bolivia in wet lower montane forest.

Arcas delphia Nicolay, 1971 , type locality: Costa Rica

katia Salazar, 2001, type locality: Colombia, nom. nud.

katia K. Johnson & Salazar, 2002, type locality: Colombia

Distribution and Habitat. Costa Rica to western Ecuador in wet lowland forest.

Arcas tuneta (Hewitson, 1865) (Thecla) , type locality: [ Brazil (AM)]

marginata Austin & K. Johnson, 1995, type locality: Brazil (RO)

viriditas Austin & K. Johnson, 1995, type locality: Brazil (RO)

arcadia Bálint, 2002, type locality: Brazil (SC)

Distribution and Habitat. The Guianas to southern Brazil in wet lowland forest up to lower montane elevations.

Arcas gozmanyi Bálint, 2006 , type locality: Panama

Distribution and Habitat. Costa Rica to western Ecuador in wet lower montane forest.

Arcas splendor ( H.H. Druce, 1907) (Thecla) , type locality: Colombia

nicolayi Salazar & Constantino, 1995, type locality: Colombia

lecromi Salazar & Constantino, 1995, type locality: Colombia

Distribution and Habitat. Colombia and Ecuador in montane forest (mapped in Robbins et al. 2012).

Arcas alleluia Bálint, 2002 , type locality: Peru

Distribution and Habitat. Eastern Peru in montane forest.

Figures

FIGURES 1–7. Male wing pattern in the Atlides Section. Dorsal and ventral surfaces. 1. Theritas mavors. 2. Arcas imperialis. 3. Lucilda crines. 4. Pseudolycaena marsyas. 5. Brangas caranus. 6. Atlides halesus. 7. Denivia deniva.

FIGURES 9–15. Hindwing anal lobe cleft (black arrows). 9. Arcas imperialis, 10. Brangas getus, 11. Atlides cosa (with a forewing double scent pad in the discal cell—red arrow), 12. Theritas drucei, 13. Lucilda danaus, 14. Pseudolycaena damo, 15. Denivia silma.