Hesperia aurelius Plötz, 1882

Nakahara, Shinichi, Zilli, Alberto, Calhoun, John V., Espeland, Marianne, Padrón, Pablo Sebastián & Grishin, Nick V., 2022, Resolving two centuries of mistaken identity: Reinterpretation of Papilio marcus Fabricius, 1787 (Lepidoptera: Nymphalidae, Hesperiidae), Zootaxa 5195 (3), pp. 241-255 : 248-250

Hesperia aurelius Plötz, 1882

Plötz (1882: 455) described Hesperia aurelius based on an unspecified number of specimens from Brasilien (= Brazil). Despite the fact that the original description in German was not accompanied by illustrations, the existence of drawings is indicated in the original description (as t. 444), as well as evidenced from an external source ( Godman 1907). Plötz’s rather detailed description in the form of a dichotomous key (see below) suggests that his H. aurelius is in accordance with the current concept of Troyus aurelius (e.g., Godman 1900: pl. 102, figs 11, 12; Draudt 1923: pl. 188h; Zhang et al. 2019: fig. 13), largely by mentioning the snow-white tornus and anal margin of the ventral hindwing. As discussed below, the whereabouts of the type material and illustrations for the skipper species discussed in Plötz (1882) are currently unknown (but see below). Types of some African butterfly taxa described in Plötz (1880) are documented in Libert (2004) and are currently deposited at the ZIMG. Lara Lopardo (pers. comm.), the present collection manager at the ZIMG, examined Plötz’s collection of 157 skipper specimens housed in Greifswald, including 30 type specimens, and confirmed that the type material for H. aurelius is not deposited at Greifswald.

The name aurelius subsequently appeared in combination with the generic name Carystus Hübner, [1819] in Godman (1900: 585), where both surfaces of a female specimen were figured (pl. 102, figs 11, 12). The rationale of associating the species-group name aurelius to the illustration by Frederick Godman remains unknown. At some point between 1882 and 1907, Godman did receive Carl Plötz’s drawings ( Godman 1907), but little evidence exists to determine when he examined them. Actually, in the NHMUK archives there exists a copy of Plötz’s numbered drawings that Godman commissioned to Horace Knight and other artists to keep pictorial evidence of the taxa illustrated by the German entomologist. However, in the collation there are many leaps with regard to Plötz’s sequence, as Godman evidently requested copies only of the taxa lesser known to him. Unfortunately, neither aurelius nor lyrcea Plötz, 1882 (see below) were copied, likely because Godman had no doubts about their identity.

The collation is tentatively dated as from 1912 and ought to cover only the American taxa, as per the title on its binding (“ Copies of Plötz’s unpublished figures of American Hesperiidae ”), but in reality, a number of species from other zoogeographical regions are also illustrated. Godman’s (1907) statement “ I have recently had an opportunity of examining …. by the late Carl Plötz ”, suggests he was only able to examine these plates just prior to Godman (1907), and not during the course of preparing Godman (1900). Having died in 1886, Carl Plötz was not able to provide his illustrations to Godman in this time-frame, and we are unable to trace how drawings ended up with Godman. Plötz’s originals seem to have ended up in ZSM, where a number of them are pinned inside the Hesperiidae drawers. It is therefore likely that additional drawings may be in the massive and yet unsorted miscellaneous collection of Plötz’s documents, letters, manuscripts etc. in the ZSM library (A. Hausmann & U. Buchsbaum, pers. comm.).

Godman’s (1900) illustration of aurelius on pl. 102, figs 11, 12, appears to be in accordance with how the species is recognized today. largely by having a white posterior band on the hindwing covering most of the inner margin (in accordance with Plötz’s (1882) description). Despite being treated as a valid species, Godman (1900) noted that “ Carystus ” aurelius is merely a form of C. marcus since he could detect no difference in the male genitalia of these two taxa. This species-group name has since been considered subspecific by some authors (e.g., Evans 1955; Mielke 2004, 2005) and species-level by others (e.g., Draudt 1923; Steinhauser 1975), although none of these authors provided meaningful arguments towards its taxonomic status. Evans (1955) did not illustrate the genitalia for aurelius , perhaps for the same reason Godman (1900) did not figure them, namely that they are identical to P. “ marcus ”. The series of T. aurelius at NHMUK, 46 of which were examined by Evans (1955), appear to consist of specimens that fit the current concept of Troyus aurelius . These specimens, as well as literature references where the specific epithet “ aurelius ” was associated with figures (see above), show a consensus in the characters throughout time regarding the identity of the skipper taxon represented by the name “ aurelius ”. Furthermore, Zhang et al.’s (2019) genetic data supports its species-level status, rather than as a subspecies of Troyus “ marcus ”. Finally, the ambiguous application of the species-group name justifies our consideration of the specific epithet “ aurelius ” as “in use” and should not be applied to the current concept of P. “ marcus ”, compared to the name “ phyllides ” discussed below.

Descending order of the relevant key couples and taxa in Plötz’ (1882) key are as such:

A, B, C, etc. a., b., c., etc. ○, ○○, ○○○, etc. ‒, ‒ ‒, ‒ ‒ ‒, etc. ^, ^^, ^^^, etc. |, | |, | | |, etc. ˅, ˅˅, ˅˅˅, etc. §, §§, §§§, etc.

A. Antennae almost always more than half the length of the forewing

b. [p. 323] Wings with hyaline spots. [opposed to: a. Wings without hyaline spots.

○○ [p. 324] The palpi are not red. [opposed to: ○ Upperside black, The body and the base of the wing roots with glossy blue or green long scales (hairs), forewing with white glass spots. Palpi red.]

‒ ‒ ... ‒ [p. 453] Upperside black. FW with a pale spot in cell 1, a white hyaline spot in cell 2, one in cell 3, a half or a point in the middle cell and two points in cells 6 and 7. HW with a large white or yellow spot in the middle and against the anal margin such a ray. Beneath have the FW a large pale yellow spot in front of the apex or at least in cells 4 and 5, the HW are yellowish, vein 6 is mostly very darkened in its entire length and the anal angle is darkened. [opposed to all the other ‒ ‒ ... ‒ couples of the key, with diverse comments.]

^^ [p. 454] Forewing with a dot or line on upper part of the discoidal cell. Hindwing underside with a narrow brown longitudinal stripe. [opposed to: ^ FW with half a spot on the inner margin of the central cell and a blue stripe on the rear edge of the wings. HW above with a large white central spot and two blue rays, beneath with a broad brown longitudinal stripe along vein 6, brownish anal margin and tornus. Collar red.]

| [p. 454] Discal spot on the hindwing upperside sharply limited [yes], tornus blackened on the underside. [opposed to: || Hindwing above with a white large central spot that flows into the rear corner up to vein 2, below with the tornus and the anal margin snow-white. Forewing below with a large pale yellow spot at the apex. Collar red.]

˅ [p. 454] All the spots are white on the upperside. [opposed to: ˅˅ The forewing spot in cell 1, the spot and the streak on the hindwing, the fringes, and, on the underside, the costa of the forewing are pale sulfur yellow. Collar black.]

§ [p. 454] The pale spot beneath at the apex of the FW is washed out [=fading]; on the HW the white middle spots elongated. → Marcus [opposed to: §§ On the forewing underside, the hyaline spots in cells 4 and 5 are sharply delimited; on the hindwing, the white center spot is rounded on the rear flights. Collar red. Club of the antenna with a white point.]

§§ [p. 454] The pale spot beneath in cells 4 and 5 of the FW is sharp delimited; on the HW the white spot is rounded. Collar red. Head dotted with white. → Lyrcea [opposed to: § On the forewing underside, the lower hyaline apical spot is washed out; on the hindwing, the white center spot is stretched.]

|| [p. 455] HW dorsal with a white large central spot that has “flowed out” into the tornus angle up to vein 2, beneath at the tornus and anal margin snow-white. FW beneath with a large pale yellow spot in front of the apex. Neck collar red.→ Aurelius [opposed to: | Discal spot on the hindwing upperside sharply limited [yes], tornus blackened on the underside.]