Occulta Nakahara & 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 : 35-67

Occulta Nakahara & Willmott , genus novum.

Type species: Euptychia ocnus Butler, 1867 , by present designation.

Zoobank registration: https://zoobank.org/Nomenclatural Acts/7B2BBC71-C2FC-40B8-A24A-14A986151D85

Systematic placement and diagnosis. Occulta gen.n. is a member of the ‘ Splendeuptychia clade’, and it is rather distantly related to the remainder of the clade. Currently, Occulta gen.n. is modestly supported (SH-aLRT 100, UFB 75) as sister to a large clade including species-rich genera such as Caeruleuptychia , Paryphthimoides , and Splendeuptychia , among others ( Figure 10 ). Based on hybrid enrichment data, Espeland et al. (2019a) recovered Occulta gen.n. (as ‘ Magneuptychia ocnus ’) as sister to ‘ Erichthodes ’ narapa (now Capronnieria narapa comb.n.) and Capronnieria galesus , although with only moderate support (BS and PP>0.75 <0.95). This relationship, with similar low support, was also found in the backbone tree in this study ( Figure S1 ). The single species of Occulta gen.n. ( Figure 30 ) resembles some species of Deltaya gen.n. (see Figures 33 and 34 below), but may be distinguished by possessing elongate, ‘smudge-like’ orangish spots with a silver marking in the middle in VHW cells M 2 and M 3, whereas the ocelli in these cells in Deltaya gen.n. are more rounded and have double silver spots encircled by a better defined yellowish ring. Furthermore, the dark ventral discal and postdiscal bands are typically narrower in Occulta gen.n. compared to Deltaya gen.n. species, perhaps with the exception of D. ocypete , whose ventral bands are often narrower in comparison with other closely related species. In particular, in Occulta gen.n. the VHW marginal band is of even width throughout, whereas this band forms a ‘wedge-shaped’ swelling at the tornus in Deltaya gen.n. In addition, Occulta gen.n. possesses a tiny, rather incomplete ocellus in VHW cell Cu 2, which is absent in Deltaya gen.n. The male genitalia also differ between Occulta gen.n. ( Figure 31 ) and the type species of Deltaya gen.n. and close relatives (referred to as ‘core’ Deltaya gen.n.) ( Figure 34 ), at least, by the lack of a developed ‘hump’ on the dorsal margin of the valva, and instead only have a slightly serrated region at the dorsal margin distal of the costa. In lateral view, the costa appears as a narrow plate in Occulta gen.n., whereas the costa appears as a somewhat trapezoidal plate in lateral view in ‘core’ Deltaya gen.n. See description of Deltaya gen.n. below for details about ‘core’ Deltaya gen.n.

Etymology. The generic name is a Latin feminine adjective treated as a noun in the nominative singular, ‘occulta’, meaning a ‘hidden’ or ‘secret’ thing, in reference to the former concealment of this taxon within Magneuptychia . The generic name is also coined in alliteration with the species-group name.

Description ( Figures 30 and 31 ). Wing pattern and shape as illustrated ( Figure 30 ). Other notable characters include eyes setose; pterothoracic legs dorsally darker, tibia with two principal longitudinal rows of spines ventrally, in addition to some spines laterally, pair of spurs of similar length at distal end of tibia, first tarsomere with three principal longitudinal rows of spines ventrally, remaining distal tarsomeres with four principal longitudinal rows of spines ventrally. Medium-sized Euptychiina (FW length typically 23 – 26 mm), DFW and DHW of males without obvious androconial scales, but long setiform scales visible in discal cell and adjacent areas, especially extending along inner margin. Male with 8th tergite a narrow stripe at basal side of the eighth abdominal segment, broad weakly sclerotized patch present at posterior side of eighth abdominal segment; genitalia as illustrated ( Figure 31 ); costa appearing as a narrow plate in lateral view; cornuti present, otherwise genitalia as illustrated ( Figure 31 ). Female genitalia ( Figure 31 ) with intersegmental membrane of between seventh and eighth abdominal segment somewhat pleated and expandable with very weak sclerotization ventrally; lamella antevaginalis membranous; eighth segment with irregular lateral sclerotized plate narrowing slightly dorsally; pair of well-defined signa present.

Occulta Nakahara & Willmott , gen.n.

ocnus ( Butler, 1867) , comb.n., was Magneuptychia

= gracilis ( Weymer, 1911) , comb.n., was Magneuptychia

Figures

FIGURE 1 Summary tree based on the FULL dataset showing the major clades supported in this study. Colours are the same as in Espeland et al. (2019a). Support for major clades is shown. Interpretation of support values can be found in the legend.

FIGURE 10 Phylogeny of the ’Splendeuptychia 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 30 Occulta ocnus comb.n. (a) male wing venation; (b and c) male (LEP-10408) dorsal (b) and ventral (c); (d and e) female (ST ocnus) dorsal (d) and ventral (e), with specimen labels. Scale bars 1 cm.

FIGURE 31 Occulta ocnus comb.n. (a and b) male genitalia (dissection SN-19-157), lateral (a) with posterior view juxta, aedeagus lateral (b); (c–e) female genitalia (dissection NHMUK010402850), lateral view exterior tip abdomen (c), ventral view exterior tip abdomen (d), dorsal view interior abdomen (e), corpus bursae perpendicular to signa (f). Scale bars 1 mm.

FIGURE 33 Deltaya ocypete comb.n. (a) male wing venation; (b and c) male (FLMNH-MGCL-209681) dorsal (b) and ventral (c); (d and e) female dorsal (d) and ventral (e). Scale bars 1 cm.

FIGURE 34 Deltaya gen.n. representative species. (a) D. opima comb.n; (b) D. louisammour comb.n (FLMNH-MGCL-111522); (c) D. andrei comb.n; (d) D. probata comb.n. Scale bars 1 cm.