Oligowithius achagua, Romero-Ortiz & Sarmiento & Harvey, 2023

Romero-Ortiz, Catalina, Sarmiento, Carlos E. & Harvey, Mark S., 2023, A new genus and five new species of pseudoscorpions (Arachnida, Pseudoscorpiones, Withiidae) from Colombia, ZooKeys 1184, pp. 301-326 : 301

Oligowithius achagua sp. nov.

Figs 1D , 2 , 8 , 9E, F , 10 , 11

Material examined.

Holotype. Colombia • ♂; Meta, Puerto Gaitán, Carimagua ; 160 m; 22 Apr. 2012; D. Martinez leg.; estuary on the eastern plains; ICN-APs-388.

Paratypes. Colombia • 1 ♂ and 1 ♀; Meta, same data as the holotype .

Diagnosis.

Oligowithius achagua sp. nov. differs from O. abnormis by its smaller size (1.7 mm vs 2.18 mm in O. achagua ), more slender patella in O. achagua (3.05 × longer than broad) than in O. abnormis (2.74 ×), and a stouter chela in O. abnormis (3.70 × longer than broad) than in O. achagua (4.05 × longer than broad).

Description.

Adults. Color: yellowish brown; carapace and pedipalp reddish brown; legs yellowish, paler than the abdomen, darker in the edges; carapace metazone without paired pale spots (Fig. 1D ).

Dimensions (mm): male: holotype (followed by male paratype): body length 2.18 (2.10). Pedipalps: trochanter 0.33/0.16 (0.27/0.15), femur 0.58/0.15 (0.54/0.15), patella 0.54/0.18 (0.50/0.16), chela (with pedicel) 0.94/0.23 (0.88/0.22), chela (without pedicel) 0.88 (0.84), hand (without pedicel) length 0.48 (0.43), movable finger length 0.45 (0.43). Chelicera 0.19, movable finger length 0.16. Carapace 0.74/0.58 (0.68/0.56) (width at medial area); eyespots diameter 0.08. Leg I: femur 0.14/0.14, patella 0.26/0.14, tibia 0.26/0.08, tarsus 0.26/0.06. Leg IV: femur + patella 0.47/0.16, tibia 0.34/0.11, tarsus 0.33/0.06, TS 0.76.

Female: paratype: body length 2.36. Pedipalps: trochanter 0.28/0.16, femur 0.54/0.15, patella 0.52/0.18, chela (with pedicel) 0.94/0.25, chela (without pedicel) 0.88, hand (without pedicel) length 0.48, movable finger length 0.44. Carapace 0.73/0.58.

Carapace (Fig. 8A ): 1.28 (1.20) (♂), 1.07 (♀) × longer than broad; posterior lateral margins slightly widened; with two non-corneate eyes; with 55 (♂) setae, including 2 (♂) near anterior margin, 11 (♂) near posterior margin, 21 in the medial zone and 23 in the anterior region; with two distinct furrows; posterior furrow slightly closer to posterior carapace margin than to median furrow (Fig. 8A ).

Chelicera (Fig. 8B ): with five setae on hand, sb missing, b slightly denticulate, all others acuminate; movable finger with one subdistal seta; galea of male broken in holotype, galea with multiple rami in paratype (Fig. 10A ); rallum of four blades, the most distal blade with several serrations on leading edge, other blades smooth (Fig. 8E ); two lyrifissures on dorsal side.

Pedipalp (Fig. 8C, H ): trochanter, femur, patella and dorsal chelal hand granulate, ventral chelal hand and fingers smooth; dorsal setae clavate and denticulate; trochanter 2.05 × (1.79) (♂), 1.75 × (♀), femur 3.79 × (3.58) (♂), 3.53 × (♀), patella 3.05 × (3.10) (♂), 2.95 × (♀), chela (with pedicel) 4.05 × (4.07) (♂), 3.79 × (♀), chela (without pedicel) 3.79 × (3.89) (♂), 3.55 × (♀), hand 2.07 × (2.0) (♂), 1.94 × (♀)longer than broad, movable finger 0.93 × (1.00) (♂), 0.92 × (♀)longer than hand. Fixed chelal finger with eight trichobothria, movable chelal finger with four trichobothria (Fig. 8H ): eb and esb situated basally, as well as ib and ist; est situated midway between it and isb in the middle of the finger, et close to fingertip; b and sb situated near one another, st located midway between sb and t, t parallel to it. Venom apparatus not visible, venom ducts not visible in ♂; nodus ramosus not visible. Retrolateral margin of fixed finger with two double sense-spots (Fig. 8H ) situated midway between esb and est, movable finger with one double sense-spot close to sb. Chelal teeth rounded; fixed finger with 40 (♂) teeth; movable finger with 43 (♂) teeth; accessory teeth absent.

Coxal region: coxal chaetotaxy: ♂, 6: 7: 9: 18; maxilla with 19 setae including two apical setae and one very small internal, sub-oral seta; median maxillary lyrifissure medial-anterior in position, posterior lyrifissure present.

Legs (Fig. 8F, G ): junction between femora and patellae I and II parallel, junction in legs III and IV oblique; tarsal tactile seta of leg IV situated distally, 0.76 (♂) of tarsus length (Fig. 8G ); arolium slightly shorter than claws. Ratios: leg I: femur 1 ×, patella 1.94 ×, tibia 3.30 ×, tarsus 4.72 × deeper than broad; Leg IV: femur + patella 2.85 ×, tibia 3.00 ×, tarsus 5.13 × deeper than broad.

Abdomen (Fig. 8D ): first four tergites entire, the others with faint medial suture. Tergal chaetotaxy: ♂, 12: 14: 13: 18: 18: 19: 19: 18: 19: 15: 6: 2, 2; all setae foliate; mostly uniseriate but some tergites with a few setae placed anteriorly. All sternites entire, except for the last three with a faint medial suture. Sternal chaetotaxy: ♂, 10: (1) 6 (1): (1) 8 (1): 14: 12: 8 + 13/13 gls: 8 + 18/16 gls: 8: 8: 6 (including two clavate setae): 2; sternites VII-VIII of ♂ with two small patch circles of glandular setae each (Figs 9F , 10B-D ), paratypes with one circular patch of glandular setae each (Fig. 9E ); setae uniseriate and acuminate; ♂ without paired invaginations on anterior margins of sternites.

Genitalia: simple structure with most of the components extremely reduced to chitinized lateral apodemes that do not merge with the dorsal apodemes. The level of sclerotization of the ejaculatory channel is weak; however, it is projected from the lateral apodemes, which allows us to classify Oligowithius as a Cacodemoniini (Fig. 11 ).

Etymology.

This species is named after the indigenous people, original inhabitants of the Meta, Vichada and the Venezuelan Llanos, the Achaguas. The name should be treated as a noun in apposition.

Figures

Figure 1. Habitus of the new species (males) A Paciwithius chimbilacus sp. nov. B Cystowithius florezi sp. nov. C Parawithius bromelicola sp. nov. D Oligowithius achagua sp. nov. Scale bars: 0.5 mm.

Figure 2. Distribution of the new species and the new record of Withiidae from Colombia.

Figure 8. Oligowithius achagua sp. nov. (male holotype, ICN-Aps- 388) A carapace B chelicera C left pedipalp D abdomen, sternites E rallum F left leg I G left leg IV H right chela (arrow shows sense-spots). Abbreviations: Pedipalp movable finger: b = basal; sb = sub-basal; st = sub-terminal; t = terminal; fixed finger: eb = exterior basal; esb = exterior sub-basal; est = exterior sub-terminal; et = exterior terminal; ib = interior basal; isb = interior sub-basal; ist = interior sub-terminal; it = interior terminal. Cheliceral setae: b = basal seta; es = exterior seta; is = interior seta; ls = laminal seta. Scale bars: 8 µm (A, C, D, F-H); 2 µm (B, E). Granulation is shown in detail on each segment in a small section but is meant to cover all the structure.

Figure 9. Glandular setae patches of the new species A Paciwithius chimbilacus sp. nov. (holotype, ICN-Aps- 076) B Parawithius bromelicola sp. nov. (holotype, ICN-Aps- 082) C Paciwithius valduparensis sp. nov. (holotype, ICN-Aps- 597) D Cystowithius florezi sp. nov. (holotype, ICN-Aps- 07) E, F Oligowithius achagua sp. nov. E male paratype (ICN-Aps- 388) F male holotype (ICN-Aps- 388). Scale bars: 0.1 mm (A-C, E, F); 0.05 mm (D).

Figure 10. Oligowithius achagua sp. nov. (male paratype, ICN-APs- 388) A right galea B sternites VII-VII C patch of glandular setae on sternite VIII D detail of the glandular setae on sternite VIII. Scale bars: 100 µm (A, B); 10 µm (C); 5 µm (D).

Figure 11. Light micrograph of male genitalia of Oligowithius achagua sp. nov. (holotype, ICN-Aps- 388). Scale bar: 100 µm.