Mastigoproctus scabrosus Pocock, 1902

Barrales-Alcalá, Diego, 2018, Systematic Revision Of The Giant Vinegaroons Of The Mastigoproctus Giganteus Complex (Thelyphonida: Thelyphonidae) Of North America, Bulletin of the American Museum of Natural History 2018 (418), pp. 1-64 : 32-33

Mastigoproctus scabrosus Pocock, 1902 ,

stat. nov.

Mastigoproctus giganteus scabrosus Pocock, 1902a: 48 ; Mello-Leitão, 1931: 28; Harvey, 2003: 67; Zárate-Gálvez and Chame- Vázquez, 2007: 393–395 (misidentification); McMonigle, 2013: 100, fig. unnumbered, 100 (part); Barrales-Alcalá et al., 2016: 26, 46, fig. 3A–D.

Mastigoproctus giganteus scatrosus: Franganillo, 1936: 147 .

TYPE MATERIAL: MEXICO: Oaxaca: Holotype ♂ (Natural History Museum, London) [photographs examined].

DIAGNOSIS: Mastigoproctus scabrosus , stat. nov., is among the most conspicuous North American species of Mastigoproctus and may be distinguished from M. mexicanus and M. vandevenderi , sp. nov., both of which also exhibit tubercles on the retrolateral surface of the pedipalp femur, as follows. Mastigoproctus scabrosus is sparsely setose whereas M. mexicanus is densely setose. A cheliceral-coxal stridulatory organ is absent in M. scabrosus , but present in M. mexicanus and M. vandevenderi . Spines S4 and S5 on the prodorsal margin of pedipalp trochanter of the adult male are fused in M. scabrosus , but separated in M. mexicanus and M. vandevenderi . The terminal spiniform tubercle on the retroventral surfaces of the femora of legs II–IV is conical in M. scabrosus whereas it is more tubular (digitiform) in M. vandevenderi and M. mexicanus .

DESCRIPTION: The following description is based on three males and one female.

Total length: Maximum length from anterior margin of carapace to posterior margin of opisthosomal segment XII (pygidium) in adult specimens 73.7 mm (♂) and 64.2 mm (♀) (table 3).

Color: Carapace dark reddish brown, anterior margin blackish, lateral margins dark brown. Tergites I–IX dark reddish brown, posterior and lateral margins blackish. Sternites I and II reddish brown; III–IX and pygidium dark reddish brown. Flagellum dark brown, segments with reddishbrown macrosetae. Pedipalp trochanter, femur, patella, and tibia dark brown, mesal surfaces with few reddish macrosetae; patellar apophysis, fixed finger and basitarsus, blackish, with reddish macrosetae. Legs I–IV dark reddish brown; II–IV coxae, ventral surfaces reddish brown.

Carapace: Epistoma visible in dorsal aspect. Pair of strongly developed carinae anterolater- ally, extending from lateral ocelli to two-thirds the distance to median ocular tubercle (fig. 10G). Three pairs of lateral ocelli with accessory translucent eyespot situated between anterior and posterior ocelli; anterior ocelli larger than median and posterior ocelli; anterior two pairs slightly separated from posterior pair by tubercle, distance between median and posterior ocelli 10× distance between anterior and median ocelli. Median ocular tubercle rugose, situated in anterior 10% of carapace (table 3); distance between ocelli almost 2× ocular diameter. Carapace surfaces densely granular, tuberculate mediolaterally. Posterior fovea present, distinct.

Chelicerae: Retrolateral surface without stridulatory surface; mesal surface with reddish macrosetae (figs. 4E, 5E).

Pedipalps: Cuticle punctate and tuberculate with cristulae. Coxa, retrolateral surface with cristulae; ventral surface rugose; coxal apophysis with one terminal spine; prodorsal surface smooth, with macrosetae (fig. 6E). Trochanter longer than wide; retrodorsal surface tuberculate; prodorsal margin with five terminal spines (S1– S5) and one subterminal accessory spine ( AS), varying in size such that S4> S3> S2> S5 ≥ S1> AS (♂; fig. 7G) or S4> S3 ≥ S5 ≥ S2> S1> AS (♀; fig. 7H); spaces between S2 and S3 equal to or greater than length of S2 and between S3 and S4 equal to or greater than length of S3 (♂; fig. 7G) or spines evenly spaced (♀); prolateral surface with several spiniform tubercles and reddish macrosetae (♂); proventral margin with two spines (♂). Femur laterally compressed (♂) or terete (♀), 2× (♀) to almost 3× (♂) longer than wide (table 3); prolateral surface with two spines, one prodorsal, short, blunt (♂) or sharply pointed (♀), the other proventral, sharply pointed, length almost one-third femur width (♂; fig. 9C) or short, sharply pointed, and situated apically (♀); retrolateral surface rugose, with short, blunt (♀) or long, sharply pointed (♂) tubercles. Patella slightly shorter (♂) or longer (♀) than tibia (table 3); prolateral surface with reddish macrosetae, one vestigial (♂) or distinct (♀) spine situated distally on proventral