Zaretis itylus, (WESTWOOD, 1850)

Dias, Fernando Maia Silva, Janzen, Daniel, Hallwachs, Winnie, Chacón, Isidro, Willmott, Keith, Ortiz-Acevedo, Elena, Mielke, Olaf Hermann Hendrik & Casagrande, Mirna Martins, 2019, DNA barcodes uncover hidden taxonomic diversity behind the variable wing patterns in the Neotropical butterfly genus Zaretis (Lepidoptera: Nymphalidae: Charaxinae), Zoological Journal of the Linnean Society 185, pp. 132-192 : 158-162

ZARETIS ITYLUS ( WESTWOOD, 1850)

( FIGS 8E–H, 15D, 16G, H, 19; SUPPORTING INFORMATION, APPENDIX S6)

Type material

Male holotype of Siderone itylus Westwood, 1850 with the following labels: / Type/ Rio / B.M.TYPE No. Rh 10378 Siderone itylus #m Westw[ood]./ Siderone itylus Westwood det. R.I. Vane-Wright, 1972 Holotype #m/ Itylus Westw [ood] G.D.L. p.321/ (NHMUK).

Male lectotype of Zaretes [sic] itys pseuditys Fruhstorfer, 1909 and consequently of Zaretes [sic] pseuditys Fruhstorfer, 1909 with the following labels: / Espírito Santo Brasil ex. coll. Fruhstorfer/ Fruhstorfer Coll. B.M. 1937-285/ Type/ Type/ Zaretes itys pseuditys Fruh [storfer].Det. R.I.Vane-Wright 1972 #m SYNTYPE / pseuditys Fruhst [orfer]./ LECTOTYPE Zaretes itys pseuditys Fruhstorfer, 1909 Dias, Casagrande & Mielke , det. 2012/ LECTOTYPUS / (NHMUK).

Diagnosis

Zaretis itylus , as with most species of the genus, is somewhat variable, but more-or-less distinctive. The species was recently redescribed and diagnosed by Dias et al. (2012), but the diagnosis focused on a comparison with one of the most similar and likely sister species, Z. itys , which is not sympatric with Z. itylus . Zaretis itylus is sympatric only with Z. isidora and Z. strigosus in the coastal Atlantic forests of Brazil. Males ( Fig. 8E, F) can be distinguished from the above species by the shape of the FW, which is similar to that of the female, with the outer margin evenly rounded until just before the apex; the colour of the upperside of the wings, which is reddish brown, with the marginal and submarginal areas suffused with reddish brown; and the shape of the HW, which is strongly emarginated at Sc–Rs and projected at Rs, resembling the wing shape of a female. Females ( Fig. 8G, H) are similar to Z. itys , but the FWD and HWD basal areas are generally darker, and the FW discal spot less developed; nevertheless, they can be distinguished from Z. isidora and Z. strigosus (and from Z. crawfordhilli sp. nov.) by the same set of characters.

Discussion

Zaretis itylus was recently redescribed and discussed by Dias et al. (2012). This name was widely misused in the past by several authors, who presumably, owing to its type locality, assumed it to represent the phenotype of Zaretis occurring in southern and southeastern Brazil. However, Z. itylus represents a distinctive, rare and restricted species. Numerous citations to Z. itylus in fact represent Z. strigosus or Z. isidora (see Dias et al., 2012). Siderone itylus Westwood, 1850 was described from a single male specimen ( Hemming, 1941), thought to be a female by Westwood owing to the lack of forelegs in the holotype and the unusual wing shape ( Dias et al., 2012). The species represented by the names Zaretes [sic] pseuditys Fruhstorfer, 1909 and Zaretes [sic] itys pseuditys Fruhstorfer, 1909 was described twice by Fruhstorfer (1909a, b; certainly by a lapsus memoriae), first as a species ( Fruhstorfer, 1909a), based on an unstated number of specimens from Espírito Santo, Brazil, and later as a subspecies ( Fruhstorfer, 1909b), based on four specimens from the same locality. Most probably, both descriptions were based on the same three males and one female specimen collected by Mr J. Michaelis and cited in the latter publication. Therefore, the male lectotype designated by Dias et al. (2012) applies to both names. Although Willmott & Hall (2004) found all four of Fruhstorfer’s syntypes in the NHMUK, Vane-Wright (1975) located only two males and one female. Only two of those specimens are currently in the NHMUK type collection, the male lectotype designated by Dias et al. (2012) from Espírito Santo, Brazil, illustrated by Warren et al. (2016), and one female paralectotype from the same locality.

Distribution Restricted to dense ombrophilous forests of coastal Brazil ( Rio de Janeiro , Espírito Santo, Bahia; Fig. 19). It is not known whether this species occurs further north or south along the Brazilian coast, where it might be expected based on the distributions of endemic species with which it occurs.

Examined material See Supporting Information, Appendix S1.