Pachythone palades Hewitson, 1873

Dolibaina, Diego Rodrigo, Dias, Fernando Maia Silva, Mielke, Olaf Hermann Hendrik & Casagrande, Mirna Martins, 2024, An overview of the Brazilian Atlantic Forest species of Pachythone Bates (Lepidoptera: Riodinidae), with the description of a new species and an updated checklist of Pachythonina, Zootaxa 5523 (1), pp. 35-48 : 39-41

Pachythone palades Hewitson, 1873 syn. nov

( Figs 7–17 , 23 )

Comments. Hewitson (1873) described both P. palades and P. pasicles from Espírito Santo state, Brazil. Pachythone palades is described in page [69], based on an unknown number of female specimens, even though Kirby (1879) mentioned five specimens in Hewitson’s collection. Two different females were illustrated in the original description, one representing the assumed “usual color” ( Hewitson (1873), pl. [37], fig. 2) and other a “variety” ( Hewitson (1873), pl. [37], fig. 1). Two female syntypes, deposited at the NHMUK, match the original description and illustrations of P. palades . D’Abrera (1994) wrongly assumed that the one female syntype representing the “variety” was the only type specimen of P. palades deposited at the NHMUK. He overlooked the label that explicitly identifies the other female syntype of P. palades , wrongly recognizing it as a female type of P. pasicles . The marked pattern of fine lines of orange scales on both wings surfaces of the “variety” of P. palades is the only character that distinguishes it from its “usual color”. Similar intraspecific variation is also observed in other species of the genus, as in females of P. conspersa Stichel, 1926 , for example.

On page [70], Hewitson (1873) described a second species, P. pasicles , also based on an unknown number of male and female specimens; Kirby (1879) mentioned two specimens in Hewitson’s collection. The description is said to be based on the female specimen, and the male is only mentioned briefly, indicating that it differs from the female only in its smaller size. However, apparently all specimens used by Hewitson (1873) in the description P. pasicles are males.

The study of the type series of P. palades and P. pasicles reveals that the dark brown dots and spots on the dorsal and ventral fore and hind wings are virtually identical in both species. It is likely that P. palades and P. pasicles are sympatric, based on the known distribution of the species. Additionally, P. palades is only known from female specimens and P. pasicles from male specimens. Considering this evidence, these names most possibly represent a single species. Even though P. palades was described on page [69] and P. pasicles on page [70], both species were illustrated together earlier, in plate [37]. These pages and plates are assumed to have been published in the same volume and number, on January 1 st 1873, however, Lamas (2023) assumes it had been published on January 8 th 1873. As pages and plates within a publication are considered to have been published on the same date, the Principle of the First Reviser ( ICZN 1999, Art. 24.2.1) is invoked to select Pachythone pasicles as the senior subjective synonym and P. palades as its junior subjective synonym (syn. nov.). Pachythone pasicles was described based on male specimens, and since males tend to have more informative characters than females and females tend to be similar and more easily confused between species of Pachythone , the selection of a species described based on male specimens will best serve stability and universality of nomenclature ( ICZN 1999, Recommendation 24A).

Pachythone pasicles is rare and, as far as known, not represented in any major Brazilian collections. Several collecting trips conducted in various habitats in Espírito Santo state, including low-elevation hilltops, yielded no specimens of P. pasicles . However, a female identified as P. pasicles was recently recorded at the Reserva Vale, in Linhares, north of Espírito Santo, Brazil on July 31, 2022, by Ítalo dos Santos Agustinho ( Agustinho 2024) ( Fig. 17 ), suggesting the tableland forests north of Doce river as the species typical habitat.

Pachythone crepusculi , recently described by Gallard & Fernandez (2017) based on specimens from French Guyana, is remarkably similar to the Atlantic Forest endemic P. pasicles . However, Gallard & Fernandez (2017) note that P. crepusculi is smaller than P. pasicles , with more rounded wings (margins straighter and apex somewhat pointed in P. pasicles ), more marked spots, and wider submarginal bands in the underside of the wings (spots duller and bands narrower in P. pasicles ), the postdiscal band along the outer margin on the hind wing underside is somewhat angled (band smoothly curved in P. pasicles ), and the fringes have three white spots (uniformly brown in P. pasicles ).

Type material. Pachythone palades was described based on at least two female specimens from Espírito Santo state, Brazil. Two female syntypes are deposited at the NHMUK. The female specimen regarded by Hewitson (1873) as of the “usual color” (i.e. typical) is here designated lectotype, to ensure stability and the correct identification of the name, bearing the following labels: / Type/ Espirito Santo [, Brazil] Hewitson Coll. 79-69. Pachythone palades 2/ NHMUK 010247232/. The following labels will be added to the specimen: / LECTOTYPUS / Lectotype of Pachythone palades Hewitson, (1873) Dolibaina, Dias, O. Mielke & Casagrande des. 2024/. The female specimen regarded by Hewitson (1873) as the “variety” is here designated as paralectotype and will be labeled accordingly.

Pachythone pasicles was described by Hewitson , (1873) from at least two specimens from Espírito Santo state, Brazil. Two male syntypes, one of them erroneously regarded as a female by Hewitson (1873), are deposited at the NHMUK. One of the syntypes is here designated lectotype to ensure stability and the correct identification of the name and has the following labels: / Type / Espirito Santo [, Brazil] Hewitson Coll. 79-69. Pachythone pasicles . 2./ B.M.(N.H.) Rhopalocera Slide No. 29882/ NHMUK 010247231 /. The following labels will be added to the specimen: / LECTOTYPUS / Lectotype of Pachythone pasicles Hewitson, (1873) Dolibaina, Dias, O. Mielke & Casagrande des. 2024/. The other male syntype is here designated paralectotype and will be labeled accordingly.

Distribution. This species is only known to occur in lowland forests in the north of the Espírito Santo state, Brazil, although it is expected to live in similar, continuous habitats in the Bahia state.

Figures

FIGURE 17. Pachythone pasicles, female recorded from Reserva Vale, Linhares, Espírito Santo, Brazil at July 31, 2022 (Agustinho 2024).

FIGURE 23. Distribution map of the species of Pachythone endemic to the Brazilian Atlantic Forest.

FIGURES 7–12. Pachythone species endemics from the Atlantic Forest of Brazil, in dorsal (left) and ventral (right) views. 7–12. P. palades: 7–8, female lectotype; 9–10, female paralectotype. P. pasicles: 11–12, male lectotype.All specimens are from Espírito Santo and are deposited at the NHMUK. Scale bar: 1 cm.

FIGURES 13–16. Original illustration of Pachythone palades (Figs 13–14) and P. pasicles (Figs 15–16) (adapted). 13–14. P. palades: female, dorsal view of the variety and dorsal view of the usual form. 15–16. P. pasicles: male, ventral view and dorsal view of the male (regarded as a female).