Vettius phyllides Röber, 1925

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 : 251-252

Vettius phyllides Röber, 1925

The species-group name phyllides was established based on a single male and female individuals from Santa Catarina [ Brazil] ( Röber 1925: 99). The first half of the original description serves as the diagnosis to distinguish Vettius phyllides from V. phyllus based on wing pattern differences: “ I have one pair of this species from Santa Catharina [ Brazil], and also one pair of phyllus from the same locality before me, both species are similar sized. The forewings of phyllades [sic] are somewhat narrower, and the posterior half of the hindwings is more curved in than in phyllus. The hyaline spots are smaller in phyllades [sic] than in phyllus, the phyllides female has two post-apical spots. The hind wings show clean, broad white, middle bands (without blue coloration) that start before the M 3 (=hintere Radialis) and reach until the above the 3A (=Innenrandrippe), but is divided by the black 2A (=Submediana); the fringes on the inner margin and in the anal angle are strikingly white and long; the underside of the forewings is almost identical in both species, but the white subapical drawings are more developed in phyllides, which is also the case for the light spot at the inner margin. The underside of the hindwings is white with yellow tint on the anal part; from the wing root stretching along the M 3 (=Mediana?) and the M 1 (= vordere Radialis), as well as at the end of the discoidal cell, from off the 2A to the outer margin there is one narrow grey band, respectively, which both unite in a large, proximally not clearly differentiated spot, at the outer margin between M 1 and Cu 1; in the anal angle, there, however, is a large, dark green distally and proximately undifferentiated spot set apart from the margin. The color of the upper side of the body is identical to that of the wings, but with white hairs, the collar brown, a large white spot in front of each antenna, palpi white with bluish scales; underside of the thorax and body white, and so are the legs; antennae as the wings, the clubs with yellowish underside.”

Subsequently, Evans (1955: 182) synonymized V. phyllides under Papilio “ marcus ” without providing justification for this taxonomic rearrangement. He apparently examined specimens from southern Brazil, Paraguay, and Argentina, and they enabled him to reach a conclusion regarding the identity of V. phyllides , given its type locality of Santa Catarina, Brazil. This status as a junior synonym of Papilio marcus Fabricius, 1787 was followed by subsequent authors (e.g., Bridges 1983, 1994). In particular, Mielke (1989: 138) mentioned the examination of a pair of syntypes housed at SMT and designated the male syntype as a lectotype ( Fig. 1D ), consequently treating the name as a junior subjective synonym of P. marcus Fabricius, 1787 . The information regarding the lectotype and paralectotype of V. phyllides , including associated labels, is also reflected in Nekrutenko (2003: 87). There exists no revisionary work on relevant groups to date, and the status of V. phyllides as a junior subjective synonym of Papilio marcus has been retained in all the literature regarding Hesperiidae classification ( Mielke, 2004, 2005). The name was therefore never treated as valid subsequent to Evans (1955).

Phenotypic inspection and genomic sequencing of the V. phyllides lectotype reveals that it is not conspecific with V. phyllus , and instead belongs to the genus Troyus ( Fig. 3 , red and magenta). The two genera Vettius and Troyus are not sisters, each being recovered as sister to other genera, Thoon Godman, [1900] and Monca Evans, 1955 , respectively, than to each other ( Fig. 3 ). Because P. marcus is a junior subjective synonym of V. phyllus , and V. phyllides is not even congeneric with V. phyllus , V. phyllides cannot remain as a synonym of P. marcus . Reviewing all available names in Troyus , we were not able to find one that could be applied to V. phyllides . Therefore, we propose that Troyus phyllides is a species-level taxon (reinstated status, new combination). This species has been frequently misidentified as Troyus marcus : one such specimen from Suriname is included in the tree ( Fig. 3 ). Finally, the phylogenetic tree reveals that Troyus aurelius is sister to T. phyllides ( Fig. 3 , red and blue).

In conclusion, given the circumstances surrounding the species-group names associated with Papilio marcus Fabricius, 1787 , we propose the following three taxonomic changes:

(1) Treatment of Papilio marcus Fabricius, 1787 as a junior subjective synonym of P. phyllus Cramer, 1777 (new synonym). By virtue of article 23.9.5 of ICZN (1999), the current placement of Papilio marcus Fabricius, 1787 in Vettius Godman, 1901 was already preventing its automatic replacement as a junior primary homonym of Papilio marcus Schaller, 1785 (now in Morpho Fabricius, 1807 ), so pending referral of the case to the ICZN, prevailing usage had to be maintained. Removing P. marcus from use as a valid taxon following the above synonymy also eliminates referral to the ICZN as Article 23.9.5 applies only to species-group names “in use”.

(2) Removal of the name Vettius phyllides from the synonymy of P. marcus and consideration of this specific epithet as a name to represent a concept regarded by the name Papilio “ marcus ” for nearly 200 years, following Article 23.3.5 of ICZN (1999) (reinstated status). The rationale of applying phyllides to P. “ marcus ” is based on the fact that these two specific epithets have been associated with each other since Evans (1955), and continued to be considered as conspecific in the recent comprehensive catalogue of Hesperiidae ( Mielke 2004, 2005). Furthermore, the genomic sequencing data supports the lectotype of V. phyllides as conspecific with specimens that have been misidentified as P. marcus Fabricius, 1787 . On the other hand, as explained above, aurelius and other relevant species-group names currently associated with the genus Troyus are no longer associated with Papilio “ marcus ” and, importantly, type material is not available for these taxa to settle their nomenclature. In addition, genetic data exists to support the specific status of these names, which are currently in use (Zhang et al. 2019). We argue that the application of “in use” species-group names to different taxa would cause confusion, and we avoid this situation by proposing a replacement name based on a taxon which has been considered to be a junior subjective synonym. Name-bearing types exist for both Papilio marcus Fabricius, 1787 and Vettius phyllides Röber, 1925 , allowing the removal of any ambiguity regarding the application of these names.

(3) Proposal of the combination Troyus phyllides (new combination) as a name to refer to a skipper species known as Vettius marcus for over 100 years until its recent taxonomic change in Zhang et al. (2019).

Figures

FIGURE 1. Pictures of relevant Troyus species:A) sequenced Troyus phyllides from Suriname (molecular voucher: 19022E04; deposited in USNM); B) genitalia of Troyus phyllides from Rondônia, Brazil (dissection vial: SN-20-107; deposited in MGCL); C) Lectotype of Papilio marcus Fabricius, 1787 housed in ZMUC (ZMUC 00029699); D) Lectotype of Vettius phyllides housed at SMT (molecular voucher: 18094F06).

FIGURE 3. Phylogenetic tree of Vettius and Troyus representatives constructed from protein-coding regions of the Z chromosome.