Argentaria Huertas & Willmott, 2023

Espeland, Marianne, Nakahara, Shinichi, Zacca, Thamara, Barbosa, Eduardo P., Huertas, Blanca, Marín, Mario A., Lamas, Gerardo, Benmesbah, Mohamed, Brévignon, Christian, Casagrande, Mirna M., Fåhraeus, Christer, Grishin, Nick, Kawahara, Akito Y., Mielke, Olaf H. H., Miller, Jacqueline Y., Nakamura, Ichiro, Navas, Vanessa, Patrusky, Brooke, Pyrcz, Tomasz W., Richards, Lindsay, Tan, Denise, Tyler, Stephanie, Viloria, Angel, Warren, Andrew D., Xiao, Lei, Freitas, André V. L. & Willmott, Keith R., 2023, Combining target enrichment and Sanger sequencing data to clarify the systematics of the diverse Neotropical butterfly subtribe Euptychiina (Nymphalidae, Satyrinae), Zoological Research 2023, pp. 1-73 : 25-59

Argentaria Huertas & Willmott , genus novum.

Type species — Euptychia itonis Hewitson, 1862 , by present designation.

Zoobank registration: https://zoobank.org/Nomenclatural Acts/F5A5D4DD-82D3-40AA-BD88-978B9A55AB46

Systematic placement and diagnosis. Argentaria gen.n. is a member of the ‘ Amphidecta clade’, in which its monophyly is strongly supported in all datasets (FULL dataset, SH-aLRT 100, UFB 100, Figure 6 ). However, its relationships to other members of the clade, which include (among described species) Zischkaia , Amphidecta , ‘ Euptychia ’ ordinata / insignis , and ‘ Pharneuptychia ’ innocentia , are not strongly resolved. The new genus can be distinguished from other Euptychiina by the combination of the following three characters: (a) the VFW has a postdiscal series of ocelli extending from cell 2A-Cu 2 to M 2 -M 1, with these ocelli similar in form and elongate parallel to the wing margin, often with either a linear silvery pupil or double pupils in each cell ( Figure 17 ). In some individuals of A. salvini comb.n., the ocelli are fused into a continuous band and the pupils absent, thus superficially resembling the dark postdiscal band, which surrounds the postdiscal ocelli in other species (e.g. Magneuptychia libye ). (b) the VHW has the postdiscal ocellus in cell M 3 -M 2 elongated parallel to the veins, with the silvery pupil divided into two distinct spots, except in A. clementia comb.n., in which the two spots touch or are partly fused ( Figure 17 ). A few other species have an elongated pupil similar to that in A. clementia comb.n., such as Splendeutychia purusana comb.rev. or Nhambikuara furina comb.n. (c) the VHW tornus in cell 2A-Cu 2 has several silver streaks, which appear to represent the pupils of ocelli in both the anterior and posterior half of the cell, with the former often being split into two or elongated and pinched in the middle, while the latter is visible as an additional silver spot in some species (e.g. A. itonis comb.n.) ( Figures 18 and 19 ). Other genera with an elongate ocellus and silver pupil in cell 2A-Cu 2, such as Nhambikuara , have only a single pupil that is not as elongate as in Argentaria gen.n. The genitalia of both sexes ( Figure 19 ) are described below and are broadly like those of a number of other relatively distantly related euptychiine genera (e.g. Amiga , Pseudeuptychia , Scriptor ). Notable features include, in the male, the lack of cornuti in the aedeagus (similar to many other euptychiine genera), and in the female, the pleated, expandable intersegmental membrane between the seventh and eighth abdominal segments, antrum and lamella antevaginalis membranous, and small, round corpus bursae with slender, elongate, converging signa. The other two described genera within the ‘ Amphidecta clade’, namely Amphidecta and Zischkaia , each have distinctive male and female genitalia differing in numerous respects from Argentaria gen.n., with these distinctive characters apparently representing generic autapomorphies ( Marín et al., 2017; Nakahara, Zacca, et al., 2019; Nakahara pers. obs.).

Etymology. The generic name is a feminine Latin noun in the nominative singular, meaning a silver-mine, in reference to the distinctive silver scales arranged as spots on the ventral hindwing and forewing of species in this genus.

Description ( Figures 17 – 19 ). Some notable characters include: eyes naked; pterothoracic legs dorsally slightly darker, tibia with two principal longitudinal rows of spines ventrally, pair of spurs of similar length at distal end of tibia, first tarsomere with three principal longitudinal rows of spines ventrally, remaining tarsomeres with four principal longitudinal rows of spines ventrally. Small to medium-sized Euptychiina (FW length typically 15 – 25 mm), FW triangular and varying from being rather pointed (e.g. A. itonis comb.n.) to more rounded (e.g. A. quadrina comb.n.), HW rounded with margin variably undulating. No strong sexual dimorphism in most species: Dorsal wings dark grey brown, some species with white patches in discal part of DFW, and white patches in basal or discal part of DHW and yellowish or orangish distally, no androconial scales present except in male A. libitina comb.n., which has dark androconial scales lining the DFW cubital vein and basal part of vein Cu 2, and basal part of vein 2A. Ventral wings showing relatively large inter-specific variation in pattern across the genus, with ground colour ranging from dark grey-brown to paler yellowish brown; a dark discal and postdiscal line traversing both wings, ranging from a thin, irregular line to a straight, broad band, which may be absent or scarcely visible in some species; discal area of one or both wings often white to pale yellowish brown, sometimes extending basally or distally beyond postdiscal line; VFW with series of narrow postdiscal ocelli in cells 2A-Cu 2 to M 2 -M 1, elongated parallel to distal margin, usually with pupil present as single silver line or double silver spots, often fused into a broad band, variably surrounded by orange or yellow and in some species a further black border, ocelli variably distinct across species; VHW with a complex array of postdiscal ocelli in cells 2A-Cu 2 to M 1 -Rs, with that in Cu 2 -Cu 1 typically the largest, and, along with that in M 2 -M 1, often the only ocellus to be present as a black spot with a single, double, or further modified silver pupil, remaining ocelli typically lacking black with their silver pupils enlarged into spots or streaks, orange rings around ocelli expanded and fused in all species to form an orange background around the ocelli; silver pupil in cell M 3 -M 2 elongated and pinched in the middle ( A. clementia comb.n.) or split into two spots (all other species), and that in cell 2A-Cu 2 similarly pinched or split, often forming three distinct spots in combination with a silver spot presumed to represent a posterior ocellus in that cell; two black submarginal lines parallel to wing margin with pale scaling between them, sometimes pierced by elongate silver pupils of the postdiscal ocelli. Male 8th abdominal tergite reduced dorsally, leaving a sclerotized strip along anterior edge and usually an isolated sclerotized patch in posterior portion, that can be broader (e.g. A. jadea comb.n.) or absent (e.g. A. pagyris comb.n.) in some species. Male genitalia with uncus longer than tegumen, brachia pointing dorsally of uncus or parallel with uncus and ranging from slightly longer than uncus (e.g. A. quadrina comb.n.) to very short/vestigial (e.g. A. kendalli comb.n., A. jadea comb.n., A. clorimena comb.n.); valva usually broadening at distal tip in lateral view, with distal tip sometimes with an inwardly pointing dorsal lobe (e.g. A. itonis , A. clementia , A. quadrina ) and sometimes without (e.g. A. libitina comb.n., A. kendalli comb.n., A. clorimena comb.n.); vinculum in most species (but not all, e.g., A. pagyris ) elongated above articulation with dorsal base of valva; aedeagus relatively straight and lacking cornuti. Female genitalia showing relatively little inter-specific variation, eighth tergite with small sclerotized posterior patch and thin strip at ventral anterior edge, intersegmental membrane between segments A7 and A8 pleated and expandable with a circular to quadrate sclerotized plate ventrally, eighth segment with large irregular oval lateral sclerotized plate, lamella antevaginalis and antrum unsclerotized, ductus bursae narrow and unsclerotized, corpus bursae small, circular and with two narrow, posteriorly converging signa.

Distribution and natural history ( Figure 20 ). Argentaria gen.n. species are found in rainforest and cloudforest from sea level to 2100 m, although the great majority of species are found below 1200 m. Similarly, although the genus occurs throughout the Neotropical region, only a couple of species occur west of the Andes, and the known centre of diversity is in the bamboo-rich forests of the south-western Amazon (Madre de Dios, Peru, and Acre, Brazil), where up to 10 species can be found in sympatry, and to a lesser extent in south-eastern Brazil (Atlantic region). All species occur in close association with bamboos ( Poaceae : Bambusoideae: Bambuseae), including Guadua and various species of weeping bamboos (unpublished data), and many species are known from only a handful of widely scattered localities, with a number of species still undescribed. The immature stages were recently described for A. quadrina comb.n. by See et al. (2018), which was recorded feeding on the climbing bamboo Rhipidocladum racemiflorum with several other species having been reared in south-eastern Brazil ( Freitas, 2022) and Ecuador (Willmott & Hall, unpublished data).

Discussion. The type species for this genus, Euptychia itonis , was described by Hewitson (1862) from the ‘Amazon’ based on specimens in his collection and the collection of W. W. Saunders. The underside of a specimen was illustrated in his Figure 3 and it closely matches the three syntypes examined in the NHMUK, in particular in having a thin, broken dark brown postdiscal line in the white area of the VHW, which is unique within the genus to A. itonis comb.n.

Butler (1867) placed all of the species included here in Argentaria gen.n. that were described at that time in his Division V, Subdivision 2, which he characterized as having the VHW ocelli represented as silver streaks with a large black tornal ocellus, with his correct recognition of the close relationships of the species in this group reflecting the distinctive VHW pattern of the genus. Weymer (1911) likewise successfully grouped described Argentaria gen.n. species in his ‘Clorimene [sic] group’, which he placed alongside his ‘Doxes group’, which corresponds to Nhambikuara . Forster ’ s (1964) decision to move Argentaria gen.n. species from Euptychia into his newly described genus Splendeuptychia , with type species Euptychia ashna , seems somewhat surprising, since Weymer (1911) evidently did not regard E. ashna as being closely related to the former two groups. Equally puzzling are Forster ’ s (1964) drawings of the male genitalia of A. clementia comb.n. and A. pagyris comb.n. (p. 129, figure 163, 164), which are rather different to specimens we have examined, most notably in showing an aedeagus with cornuti, which was not observed in any dissected Argentaria gen.n. In general, Forster (1964) separated numerous taxa from the genus Euptychia into different genera, based on wing pattern and male genitalia, but he also frequently grouped species by overall appearance. Lamas (2004) followed Forster ’ s arrangement, and retained in Splendeuptychia the species placed here in Argentaria gen.n., but shortly afterwards Murray and Prowell (2005) showed that, based on DNA sequence data, A. itonis comb.n. and S. ashna were distantly related. Subsequent molecular ( Espeland et al., 2019a; Peña et al., 2010) and morphological ( Huertas, 2014; Marín et al., 2017) phylogenetic studies have corroborated that discovery, including this study, which contains sequence data for all but three of the described species.

The relationships of Argentaria gen.n. to other members of the ‘ Amphidecta clade’ are not strongly resolved, but the numerous morphological differences that separate the genus from other genera within the clade, and the fact that its constituent species have universally been recognized as closely related for more than 150 years, support its recognition as a distinct genus.

Argentaria Huertas & Willmott , gen.n.

argyropsacas (Bryk, 1953) , comb.n., stat.rev., was Splendeuptychia [treated as a synonym of " Splendeuptychia " telesphora by Lamas (2004), but ventral wing pattern is distinct]

clementia (Butler, 1877) , comb.n., was Splendeuptychia

clorimena (Stoll, 1790) , comb.n., was Splendeuptychia

= boliviensis ( Forster, 1964) , comb.n., syn.n., was Splendeuptychia [wing pattern variation and DNA barcodes suggests this is a southern form of clorimena ]

cosmophila (Hübner, 1823), comb.n., was Splendeuptychia

= argenteus (Swainson, 1823), comb.n., was Splendeuptychia

hygina (Butler, 1877) , comb.n., was Splendeuptychia

itonis ( Hewitson, 1862) , comb.n., was Splendeuptychia

jadea (Brévignon & Benmesbah, 2012) , comb.n., was Splendeuptychia [Brévignon & Benmesbah (2012, Complément à l'inventaire des Satyrinae de Guyane ( Lepidoptera : Nymphalidae ), pp. 36-52, 4 pls., 1 tab. In: Lacomme, D. & L. Manil (Eds.), Lépidoptères de Guyane. Tome 7. Nymphalidae )]

kendalli (L.D. Miller, 1978) , comb.n., was Splendeuptychia

libitina (Butler, 1870) , comb.n., was Splendeuptychia

pagyris (Godart, [1824]) , comb.n., was Splendeuptychia

= ava (Anken, 1998), comb.n., was Splendeuptychia

quadrina ( Butler, 1869) , comb.n., was Splendeuptychia

salvini ( Butler, 1867) , comb.n., was Splendeuptychia

telesphora (Butler, 1877) , comb.n., was Splendeuptychia

zischkai ( Forster, 1964) , comb.n., was Splendeuptychia

Figures

FIGURE 3 Phylogeny of the Cyllopsis clade based on the FULL dataset. Interpretation of support values can be found in the legend. The scale bars under the butterfly images equal 1 cm.

FIGURE 6 Phylogeny of the Amphidecta clade based on the FULL dataset. Interpretation of support values can be found in the legend. The scale bars under the butterfly images equal 1 cm.

FIGURE 17 Argentaria itonis comb.n. (a) male wing venation; (b and c) male dorsal (b) and ventral (c); (d and e) female dorsal (d) and ventral (e). Scale bars 1 cm.

FIGURE 18 Argentaria gen.n. representative species. (a) A. clementia comb.n.; (b) A. clorimena comb.n.; (c) A. kendalli comb.n.; (d) A. pagyris comb.n.; (e) A. quadrina comb.n.; (f) A. salvini comb.n. Scale bars 1 cm.

FIGURE 19 Argentaria itonis comb.n. A-E, male genitalia (dissection KW-21-41), lateral tip abdomen (a), lateral (b) with posterior view juxta, dorsal (c), aedeagus lateral (d) and aedeagus dorsal (e); (f–i), female genitalia (dissection KW-21-60), lateral view exterior tip abdomen (f), ventral view exterior tip abdomen (g), dorsal view interior abdomen (h), corpus bursae perpendicular to signa (i). Scale bars 1 mm.

FIGURE 20 Argentaria gen.n. Species diversity mapped on a 2 degree grid. Colours ranging from dark green to red represent increasing diversity.