Zaretis itylus ( Westwood, 1850 )

Dias, Fernando Maia Silva, Casagrande, Mirna Martins & Mielke, Olaf Hermann Hendrik, 2012, Description of a new species of the genus Zaretis Hübner, [1819], with taxonomic notes on Z. itys and Z. itylus, stat. rev. (Lepidoptera: Nymphalidae: Charaxinae) and illustration of a gynandromorph, Zootaxa 3382, pp. 29-40 : 36-38

Zaretis itylus ( Westwood, 1850) , stat. rev. (Figs 17–20; 26–30)

Siderone itylus Westwood, 1850 , In: Doubleday, Westwood & Hewitson. p. 321; described from a single specimen; Rio de Janeiro.

Zaretes [sic] itys pseuditys Fruhstorfer, 1909 . p. 166–167, fig. 2 (male genitalia); described from three males and one female; Espirito Santo.

Zaretis isidora leopoldina ; Röber, 1916, In: Seitz. p. 578. p. 57, pl. 116c (male dorsal); misidentification.

Zaretis itys itys f. pseuditys ; D’Abrera, 1988. p. 720 (male dorsal).

Zaretis ( itys ?) leopoldina; Brown & Freitas, 2000. p. 78, p. 105, fig. 1f (female live specimen); misidentification.

Zaretis itys itylus ; Lamas, 2004. p. 225; syn. pseuditys Fruhstorfer, 1909 – Willmott & Hall, 2004. p. 30. – Willmott & Hall, 2004. p. 30; syn. pseuditys Fruhstorfer, 1909 .

Diagnosis: Male specimens can be distinguished from any other Zaretis species by the dark reddish brown color of the wings upper side, with the spots in the apex and in the costal margins of the forewing suffused, hardly discernible. The shape of the male forewing is similar to that of the female, with the outer margin evenly rounded until close to the apex. The emargination at the inner margin of the forewing is strongly developed, and the emargination at the apex of the hind wing has a pronounced lobe in the outer margin, also resembling the wing shape of the female. These characters, strongly different of the characters found in males of Z. itys , corroborate the specific validity of Z. itylus . Females are distinguished from most Zaretis species by the forewings upper side color pattern that is brown distally, pale at the medial area, and orange basally, similar only to females of Z. itys . However, the spot in the space M1–M2 at the end of discal cell is short, giving a more or less straight appearance to the yellowish/ creamy band along the forewing; this is more readily observable in the forewing underside. There is little seasonal polyphenism in this species.

Taxonomic comments: Z. itylus was described from a single male specimen, thought to be a female by the author, as it can be deducted from Westwood’s (1850: 321) comments: “Another species in the same collection, which I have named S. Itylus [sic], has the upper surface of the wings entirely of a dark rich red brown colour, without the slightest indication of the vitreous spots. The fore legs are unfortunately wanting, but the specimen appears to be a female”. The lack of the fore legs and the unusual wing shape of the male probably drove Westwood (1850) to that conclusion. Since no specimen other than the type was specified in the original description, Hemming (1941: 456) concluded that this specimen is the holotype of Siderone itylus Westwood, 1850 .

Fruhstorfer (1909) described Z. itys pseuditys , clearly synonymous with Z. itylus , and placed Z. itylus as subspecies of Z. isidora . Willmott & Hall (2004) presumed that Fruhstorfer’s (1909) new species was described presumably because he was unable to examine the type of Z. itylus . While Vane-Wright (1975) indicated two males and one female syntypes of Z. pseuditys in the BMNH, Willmott & Hall (2004) found all four of the Fruhstorfer’s syntypes in that collection. Given that we were unable to examine all specimens in the Fruhrstorfer’s type series and that there are at least two different species of Zaretis in the area of occurrence of Z. itylus , a male syntype from Espírito Santo, Brazil, illustrated in Warren et al. (2012) which agrees with the original description given by Fruhstorfer (1909) is here designated lectotype (see below) to avoid future uncertainty (ICZN 1999 Art. 74.7.).

Because of the similarity between females of Z. itylus and Z. itys and the lack of evidence that these species are sympatric, Willmott & Hall (2004) regarded the former species as subspecies of the latter. However, we feel that there are enough differences in both male and female coloration and wing shape (Figs 13–30) to regard these two taxa as separate species. Our study indicates that these two species are not sympatric: Z. itys is widely distributed in the Amazon basin and Z. itylus is restricted to the Atlantic coastal forests of Rio de Janeiro and Espírito Santo.

An illustration of the male of Z. itylus given by Röber (1916), is wrongly identified as Z. isidora leopoldina ( Fruhstorfer, 1909) . Brown & Freitas (2000) also misidentified as Z. ( itys ?) [sic] leopoldina ( Fruhstorfer, 1909) a female of Z. itylus recorded in the same state where Z. isidora leopoldina was described. Nevertheless, examination of the types confirms that Z. itylus is not synonymous with Z. isidora leopoldina . Finally, many authors have identified specimens collected in south and southeast Brazil and neighboring areas as Z. itylus , and frequently as a subspecies of Z. itys (e.g. Canals 2003; C. Mielke et al. 2004a, b, c; Bonfantti et al. 2011; Dolibaina et al. 2011). Most of these records must belong to another species, as Z. itylus seems to occur in a restricted range and are rather rare in collections when compared to most Zaretis species, including Z. itys .

Distribution: The know range is restricted to the Atlantic Forest along the coastlines of Rio de Janeiro and Espírito Santo; possibly also occurs in southern Bahia.

Type material of Z. itylus: The holotype of Siderone itylus is deposited in the Rothschild collection ( BMNH) and bears the following labels: / Type / Rio/ B.M. TYPE No. Rh 10378 Siderone itylus ɗ Westw./ Siderone itylus Westwood det. R.I. Vane-Wright, 1972 Holotype ɗ/ Itylus Westw G.D.L. p.321/.

Type material of Z. pseuditys: The lectotype of Zaretes [sic] itys pseuditys , here designated, is deposited in the Fruhstorfer collection ( BMNH) and bears the following labels: /Espirito Santo Brasil ex. coll. Fruhstorfer/ Fruhstorfer Coll. B.M. 1937 285/ Type / Type / Zaretes itys pseuditys Fruh. Det. R.I. Vane-Wright 1972 ɗ SYN- TYPE / pseuditys Fruhst. / LECTOTYPE Zaretes itys pseuditys Fruhstorfer, 1909 Dias, Casagrande & Mielke, det. 2012/ Lectotypus /. The characteristic lectotype labels will be sent to the curator of the BMNH collection.

Examined Material: BRAZIL: Rio de Janeiro, Guapimirim, 1ɗ 13.VIII.1941, 1Ψ 7.VIII.1941, Gagarin leg., DZ 20.000 ( DZUP); 1ɗ, no data, May leg., 19.258 ( DZUP); Guapimirim, Caneca Fina, 1ɗ 20.V.1978, Pearson leg. ( MNRJ); Duque de Caxias, Imbariê, 1Ψ 5.I.1975, 1Ψ 2.IX.1970, Ebert leg., DZ 15.505, DZ 15.491 ( DZUP); Espirito Santo, 1ɗ, no data, ex. coll. Arp, 22/883 ( MNRJ); Linhares, 1Ψ III.1973, Elias leg., DZ 15.526 ( DZUP); Linhares, Goytacazes, 2ɗ, 1Ψ 9-17.IX.1907, May leg., 27/407, 52/775 ( MNRJ); Conceição da Barra, 1Ψ 4.IX.1969, Elias leg., 15.487 ( DZUP); Colatina, 1ɗ 24.VIII.1937, May leg., 27/406 ( MNRJ).