The “Taygetis ypthima species group” (Lepidoptera, Nymphalidae, Satyrinae): taxonomy, variation and description of a new species

Abstract A new species of Taygetis Hübner, [1819] (Lepidoptera, Nymphalidae, Satyrinae) from southeastern Brazil is described: Taygetis drogoni sp. n. In addition, T. servius Weymer, 1910 and T. fulginia d’Almeida, 1922 are resurrected from synonymy and a taxonomic discussion on the species T. ypthima Hübner, [1821] and T. rectifascia Weymer, 1907 is provided. A dichotomous key for the species is also provided.


Introduction
The butterfly subtribe Euptychiina includes over 400 described species in 45 genera, being one of the most diverse groups in the subfamily Satyrinae (Lepidoptera, Nymphalidae) (Lamas 2004, Peña et al. 2010, Zacca et al. 2013). This group is predominantly Neotropical, but some species also occur in the Neartic region and in Southeast Asia (Peña et al. 2010, Matos-Maraví et al. 2013. The taxonomy of the group is among the most poorly known of all Neotropical butterflies, and the relationships within the subtribe are still in debate (Marín et al. 2011). Several genera are polyphyletic, new species and genera are regularly described, and the delimitation of the recognized genera and species needs much effort before a better understanding on the systematics of the group emerges (e.g. Freitas and Peña 2006, in press, Zacca et al. 2013. In a recent study based on molecular data, Peña et al. (2010) proposed a phylogenetic hypothesis of Euptychiina, and defined five major clades within this group. The "Taygetis clade" is one of those five major groupings and it includes 10 valid genera. A preliminary molecular phylogeny of the "Taygetis clade" (Matos-Maraví et al. 2013) gave insights on the non-monophyletic nature of most genera, and also revealed several new cryptic species waiting to be described. Taygetis appeared as polyphyletic, with Taygetis kerea Butler, 1869 and Taygetis weymeri Draudt, 1912 as part of the "Taygetina subclade", and with the clade T. ypthima+T. rectifascia (hereafter "Taygetis ypthima species group"), as part of the "Pseudodebis subclade" (Matos-Maraví et al. 2013).
The genus Taygetis comprises 27 described species and several undescribed species (Lamas 2004), which are widely distributed throughout the neotropics, from Mexico to Uruguay (Lamas 2004, Marín et al. 2011. Adult Taygetis are mid-sized to large butterflies, with brown dorsal wings and with the ventral surface resembling dried leaves (D'Abrera 1988). Some species are crepuscular and are easily captured using rotting fruit in bait traits (Murray 2001a, b). A number of species of Taygetis show high apparent intraspecific phenotypic variation, and some species have been described several times. For example, T. virgilia (Cramer, 1776) has five synonymized names (Lamas 2004).
Although intraspecific phenotypic variation appears to be common in several Euptychiina, in some cases hidden taxonomic diversity might be underestimated. Similar to T. virgilia (see above), T. ypthima is a highly variable species that has five synonymized names (Lamas 2004).
The present paper studied in detail the morphology of male and female genitalia and wing pattern variation of T. ypthima, and related species, such as its sister species Taygetis rectifascia Weymer, 1907(Matos-Maraví et al. 2013. As a result, a new species of Taygetis from Brazil is described, and T. servius Weymer, 1910 andT. fulginia d'Almeida, 1922, synonyms of T. rectifascia and T. ypthima respectively (see Lamas 2004), were revalidated.

Methods
Dissections of the genitalia were made following standard techniques. The abdomen was removed, soaked in a heated 10% KOH solution for 5 minutes before dissection of the genitalia to analyze its structures. Illustrations were prepared with the aid of a camera lucida attached to a stereoscopic microscope. Genitalia terminology follows Oiticica-Filho (1946) and Niculescu (1972Niculescu ( -1983. Distributional data were obtained from seven entomological institutions (see below) and, when possible, from the literature (Biezanko 1960, Ebert 1969, Kochalka et al. 1996, Krüger and Silva 2003, Iserhard and Romanowski 2004, Quadros et al. 2004, Uehara-Prado et al. 2004, Giovenardi et al. 2008, Paz et al. 2008, Bonfantti et al. 2009, Iserhard et al. 2010, Peña et al. 2010, Dolibaina et al. 2011, Pedrotti et al. 2011, Santos et al. 2011, Soares et al. 2011, Bellaver et al. 2012. Ventral and dorsal wings surfaces were photographed and their patterns compared to original descriptions. All previously described taxa were studied in detail, including photographs of type specimens and original descriptions. Dissections were made for individuals corresponding to all observed variation, including phenotypes corresponding to all available names for the species in this group.
All examined material belongs to the following institutions:  Diagnosis. Taygetis drogoni sp. n. is very similar to T. ypthima, differing from the latter by the following characters: forewing with pale brown dorsal post discal band less contrasting than in T. ypthima; underside pale post discal band slightly constricted at M 3 , tapering abruptly in CuA 1 -CuA 2 and becoming conspicuously thinner or even absent from CuA 2 to the inner margin; hind wing underside with the discal line evenly curved and regular, extending from the costal margin to 1A; and dark post discal line straight and only slightly irregular. Tegumen larger and protruding; valva stouter and shorter, with a larger dorsal rough area. Signa dorsal; laterally, sternum VIII not fused with tergum VIII; lamella antevaginalis without process.

DZUP
Description. Head. Brown. Post-genal area light brown. Eye glabrous, brown. Antennae without scales at apical third, mostly light brown; club dark brown with last flagellomere light brown. Labial palpus mixed with brown and light brown, with elongated scales at first and second segment; about 1.5 times total length of eye; third segment thin, same size as first. Thorax. Uniformly brown. Legs brown; meso-and metathoracic femurs light brown on inside. Forewing, size and shape: length: 34.5-37.0 mm (n = 23). Triangular, costal margin convex, apex pointed, outer margin convex, tornus rounded, inner margin straight. Forewing upper side ( Male genitalia (Fig. 6A-E). Tegumen dorsally convex, subtriangular in lateral view, ventral projection wide; appendix angular reduced. Uncus straight, down curved at apex and dorsally keeled. Gnathos larger than uncus; straight and projected dorsally, without a ventral projection at base. Anterior projection of saccus cylindrical, length equal to tegumen. Valva subrectangular, with dorsal projections at apical third; costa developed and subtriangular; ventrally covered by setae. Aedeagus straight, thin and larger than valva; opening of aedeagus almost the total length of posterior portion.
Etymology. The specific epithet refers to Drogon, one of the three dragons of Daenerys Targaryen, a fictional character from the George R. R. Martin's novel "A Song of Ice and Fire". Distribution (Fig. 8). This species occurs in southeastern Brazil (Minas Gerais and São Paulo) at elevations from 800 to 1,500 m a.s.l.
Taxonomic comments. This species has presumably not been recognized in the past because of the intrinsic phenotypic variation within Taygetis and, in particular, within T. ypthima, the most similar and probably closest species to Taygetis drogoni sp. n. The species appears cited as T. ypthima in Ribeiro et al. (2012). In Matos-Maraví et al. (2013), Taygetis ypthima PM10-02 is in fact T. drogoni (one of the paratypes, see above). A real T. ypthima (Taygetis ypthima NW 149-8) is also included in that study, and it appears as sister to T. drogoni in the phylogeny presented in that paper. The genetic distances between these two specimens in the available COI and nuclear genes provide further support for the description of T. drogoni sp. n. Diagnosis. T. ypthima can be distinguished from T. drogoni by the forewing underside submarginal band, not conspicuously constricted at M 3 ; the proximal line is oblique in M 3 -CuA 1 to the direction of the base of the wing, disjointed of the remainder of the line from CuA 1 to the inner margin; submarginal band irregular, but about the same width from M 1 to the inner margin, sometimes slightly wider at M 3 -CuA 1 ; hind wing underside with the discal line curved and irregular, extending from the costal margin to the inner margin; and proximal line of the submarginal band distinctly curved and irregular. Tegumen smaller; valva thinner and longer, with a smaller dorsal rough area. Signa ventral; laterally, sternum VIII fused with tergum VIII; lamella antevaginalis with two lateral process. Distribution (Fig. 8). Occurs in northeastern, southeastern and southern Brazil, and also in Paraguay and Argentina, from sea level to 2000 m a.s.l. Based on label data, adults are present all year round.

Taygetis ypthima
Taxonomic comments. This is the commonest and more widespread species of the group. The high intraspecific variation observed in T. yphtima yield a number of descriptions of local forms or synonyms: T. xantippe Butler, [1870], T. ophelia Butler, 1870; T. ophelia f. semibrunnea Weymer, 1910 and T. ypthima [sic] ab. lineata Kivirikko, 1936, all synonyms of T. ypthima (Lamas 2004;Warren et al. 2013). Based on collected specimens, different phenotypes associated with these taxonomic names frequently occur in a same locality. Furthermore, the genitalia of these specimens are exactly alike the genitalia of typical T. ypthima. Nonetheless, Taygetis fulginia D'Almeida, 1922, until recently considered a synonym of T. ypthima (Lamas op. cit.), is in fact a valid species, with clear differences on morphology of male and female genitalia and wing pattern (see below).
Distribution (Fig. 8). Occurs in southeastern and southern Brazil (Rio de Janeiro, São Paulo, Paraná and Santa Catarina), at elevations from 300 to 1,200 m a.s.l. Based on label data, adults are present all year round.
Taxonomic comments. Despite its superficial resemblance to T. fulginia, this species presents a very distinctive genitalia. T. rectifascia presents strong intraspecific variation in the wing pattern, which in the past has motivated the description of several aberrations and forms: Taygetis rectifascia ab. stigma Weymer, 1907; Taygetis rectifascia ab. latifascia Weymer, 1907 (all synonyms of T. rectifascia) (Warren et al. 2013). Taygetis epithyma Forster, 1964 is a nomem nudum. The genitalia of these different phenotypes are alike the genitalia of typical T. rectifascia. Diagnosis. T. servius stat. n. can be distinguished from T. fulginia stat. r. and T. rectifascia by the following characters: forewing rounded at the apex; dorsal wings light brown without any suffused dark brown bands along the outer margin; ventral hind wing with the proximal border of the submarginal band and post discal line straight and regular, forming a 2 mm wide creamy white fascia. The base of the gnathos presents a pointed ventral projection, as in T. rectifascia and T. fulginia, but differs from T. rectifascia by the absence of the claw-shaped bifid valva apex, and from T. fulginia by its stouter valva, with a shorter but wider distal projection of the valva. In additional, T. servius is considerably smaller than the other species treated in the present paper.
Diagnosis. T. fulginia can be distinguished from Taygetis ypthima and other species of the genus by the following characters: in size it is slightly smaller, the forewing is only slightly pointed at the apex, the hind wing has smaller projections at M 3 , CuA 1 and CuA 2 , similar to T. servius stat. n., the dorsal wings lack suffused dark brown bands along the outer margin. The base of the gnathos presents a ventral pointed projection, as in T. rectifascia and T. servius stat. n., but T. fulginia differs from the former by the absence of a developed dorsal projection on the valva, and from the latter by the longer and thinner distal projection of the valva, which is also longer and with a dorsally protruding area in T. fulginia. Distribution (Fig. 8). This species occurs in southeastern Brazil (Minas Gerais, Rio de Janeiro and São Paulo), from sea level to 250m.
Taxonomic comments. The description of T. fulginia was based on a single specimen in the D'Almeida collection, now deposited at DZUP (see above). This species was previously considered a synonym of T. ypthima, but the morphological study confirms its specific status and indicates closer relationship with T. rectifascia and T. servius stat. n.

Key to males and females of the "Taygetis ypthima species group"
A combination of wing shape and color pattern permits identification of all five species without dissection, and genitalia of both sexes (not included here but discussed in the text) provide diagnostic characters for all species. 1 Forewing upper side with suffused dark brown marginal band developed (Figs 1A, C; 2A, C); hind wing with long projections at CuA 1 , CuA 2 and 2A (Figs 1, 2)  Forewing underside submarginal band constricted at M 3 and reduced or absent in CuA 1 -CuA 2 (Fig. 1B, D); hind wing underside with the discal line evenly curved and regular; dark post discal line straight and more or less regular (Fig. 1B, D) (Fig. 2B, D); hind wing underside with the discal line irregular; post discal line distinctly irregular and not straight (Fig. 2B, D)  Forewing apex conspicuously pointed (Fig. 3 A-G); forewing upper side with suffused dark brown marginal band reduced (Fig. 3A, C)

Discussion
The "Taygetis ypthima species group" is not part of the genus Taygetis, but in fact a clade related to the genus Pseudodebis Forster, 1964(including Taygetomorpha L. D. Miller, 2004  The five species treated here can be easily distinguished from one another by wing pattern and genitalia, and two main subgroups can be identified based on morphology -group 1, composed of T. ypthima and T. drogoni sp. n., and group 2, composed by T. rectifascia, T. fulginia stat. r. and T. servius stat. n. Species in group 2 can be distinguished from those of the group 1 by bearing shorter tails at M 3 , CuA 1 and CuA 2 , by the lighter dorsal ground color of wings, and by a clear reduction (T. rectifascia) or total absence (T. fulginia stat. r. and T. servius stat. n.) of the suffused dark brown marginal bands. The base of the gnathos in the species of the group 2 presents a conspicuous ventral projection, and there is a longer saccus and aedeagus, and a relatively shorter posterior opening of the aedeagus. Wing color and pattern present conspicuous intraspecific variability in all five species treated here, especially in T. ypthima and T. rectifascia (Warren et al. 2013), and thorough studies including additional sources of informative characters, e.g. molecular data, might reveal hidden taxonomic diversity.
Although species in the "Taygetis ypthima species group" are not part of the genus Taygetis (a fact also reinforced by karyological data, see Brown et al. 2007), a taxonomic revision of Taygetis and related taxa is not yet available. The lack of such revision is an impediment for eventual species delimitation and the assessment of intraspecific variation as well as the usage of generic synapomorphies. In addition, the diagnosis of many genera within Euptychiina have mostly relied on wing shape and pattern of genitalia (e.g. Forster 1964), making it a hard task to correctly assign species to a genus. As a result, most recent taxonomic rearrangements within Euptychiina are based on DNA sequence data. For example, Taygetomorpha L. Miller, 2004 has been recently synonymized with Pseudodebis Forster, 1964(Matos-Maraví et al. 2013, based only on molecular data and larval morphology (Matos-Maraví et al. 2013, Murray 2001a, with no clear adult synapomorphies yet identified.
The present study revealed that morphological characters, such as wing shape and pattern, and male and female genitalia, were efficient to provide clear-cut species delimitation. However, further detailed morphological studies on Euptychiina are highly required to clarify the species and genera delimitations within the subtribe. As clear morphological keys are generated, several monophyletic groups are easily identified using informative synapomorphies (Freitas 2007, Zacca et al. 2013. Nonetheless, because of this lack of information, the description of a new genus for the five species treated here would be premature.