The identity of an elusive Chilean harvestman, Pachylus crassus (Roewer, 1943) (Opiliones: Gonyleptidae: Pachylinae), with taxonomic and distribution notes Author Acosta, Luis E. text Zootaxa 2021 2021-06-10 4984 1 134 147 journal article 4999 10.11646/zootaxa.4984.1.13 584e2dcf-4364-4770-9fb7-1a4febcc1233 1175-5326 4926753 BA9DD175-7CFA-4D80-9250-16EE6C8CE0C4 Gonyleptes acanthops Gervais, 1849 , species inquirenda urn:lsid:zoobank.org:act: 7B4B3DD8-A40D-4E33-A06B-F5410466BE20 Gonyleptes acantops Gervais 1849: 22 [presumed misprint in text: see Kury 2003 ] Gonyleptes acanthops : Gervais 1854 : pl. 1, figs “ 4♀ ”, 4a, “ 4♂ ” [=4c], d (not 4b). Pachylus acanthops : Sørensen 1902: 35 ; Roewer 1913: 40 , fig. 14 ( ♀ ); Canals 1936: 69 ; Soares & Soares 1954: 283 ; Cekalovic 1968: 8 ; 1985: 21 ; Kury 2003: 183 . FIGURES 4A–F. Comparison of diagnostic features between Pachylus crassus (A, C, E; male from Los Queñes, AMNH) and P. quinamavidensis (B, D, F; male from Vilches, CDA 000.910). A–B Concavity in posterior margin of stigmatic segment, outline and armature. C–D Trochanter IV, dorsal. E–F Patella IV, retrolateral (with retroventral apophyses absent [E] and present [F]). Not to scale. FIGURE 5. Map of central Chile giving an overview of the distribution of the genus Pachylus : P. crassus (blue dots), P. quinamavidensis (orange dots), and Pachylus spp. of the chilensis -group (red dots). Administrative regions are labelled on the sides. Abbreviations: CAU—Cauquenes Province; CCR—Cardenal Caro Province; COL—Colchagua Province; CON—Concepción Province; CUR—Curicó Province; LIN—Linares Province; Metrop. Reg.—Metropolitan Region of Santiago; Reg.— Region; TAL—Talca Province. Color gradient: below (light brown) and above (dark brown) 1000 m elevation. Inset: location of the represented area within Chile. Remarks: The recurrent inclusion of this “ghost species” in Pachylus appears to be a case of “nomenclatural remainder”, which persisted after the generic definition was refined ( Roewer 1913 ), just because it was unrecognizable. The current combination was proposed by Sørensen (1902) , to whom the species was unknown (“species mihi incognita”), a decision simply followed by subsequent authors ( Kury 2003 ). By detecting inconsistencies between text and figures, Sørensen (1902: 20 , “descriptio et figura 4 eandem speciem non representant”) concluded that Gervais (1849 , 1854) must have referred fig. 4 to G. acanthops by mistake, because it supposedly corresponds to Gonyleptes bicornis Gervais, 1849 instead (assigned by Sørensen in 1902 to his new genus Lycomedes ). For Roewer (1913) , who considered G. acanthops to be an “unsichere Art” (uncertain species), only the figure labelled as “ 4♀ ” can be linked to this species. However, the alleged mismatch is probably only true for Gervais’ (1854) figure 4b (lateral view of a male), while figures “ 4♂ ”, “ 4♀ ” (general views of a male and a female) correspond with the description of G. acanthops quite well. For example, dorsal scutum and lateral areas are described as “scarcely granulous” in G. bicornis , contrary to what Gervais’ (1854) figures “ 4♂ ”, “ 4♀ ” display: they look clearly granulous, like given in the diagnosis of G. acanthops . The general color shown in the figures is that described for G. acanthops (greenish), not that given for G. bicornis (auburn-cinnamon-colored). The only misleading feature seems to be Gervais’ (1849) statement “intra oculos unispinigero” (one spine between eyes), referring to G. acanthops . This feature alone appeared to be enough for Sørensen (1902) to include the species in his wide concept of Pachylus (as wide as to harbor species now belonging to Metagyndes Roewer, 1913 and Acanthoprocta Loman, 1899 ). In any case, a few conclusions can be drawn here: (1) Gervais’ (1854) figures “ 4♂ ” and “ 4♀ ” are likely pertinent to the description of G. acanthops given in Gervais (1849) , (2) the depicted specimens have no match with Pachylus , so G. acanthops is accordingly removed from this genus, (3) except for the ocularium, G. acanthops has a faint resemblance with the genus Sadocus Sørensen, 1886 , but as its identity is for the time being unresolved, its systematic placement is currently considered Gonyleptidae incertae sedis.