Thiratoscirtus iyomii Pett, 2024

Pett, Brogan L., Iyomi, Dieu Merci Mpongo & Mbende, Menard, 2024, Discovery of three new species of Thiratoscirtus (Araneae: Salticidae: Thiratoscirtinae) from Central African rainforest, Zootaxa 5399 (2), pp. 155-162 : 156-158

Thiratoscirtus iyomii Pett , sp. nov.

Figs 1–10

Type material. Holotype: ♁, D. R. Congo, Salonga National Park , 2°17’15.6”S, 21° 01’18.8”E, 6 December 2022, 15:29, “ pitfall traps ”, Merlijn Jocque leg (BE_ RMCA _ARA.Ara 247655) . Paratypes: 2♀, D. R. Congo, Salonga National Park , 1°39’57.5”S, 20°31’ 58.1”E, 13 December 2022, 11:11, “opportunistic search”, Brogan L. Pett leg (BE_ RMCA _ARA.Ara 247656) ; 1♀, same data as previous (BE_ RMCA _ARA.Ara 247657) .

Etymology. The specific epithet is a genitive patronym in reference to the previous great and powerful Monkoto village war chief “Iyomi”. Iyomi was capable of miracles, including crossing the Iyenge river on foot.

Diagnosis. Males of Thiratoscirtus iyomii Pett , sp. nov. are easily separated from congeners by the very broad and long embolus, arising at 3 o’clock position and insetting into the tegulum for over half of its length; the rounded and relatively broad tip of embolus which is directed anteromedially; and the tusk-like and anteriorly directed promarginal tooth. Females are separated by the rhomboidal epigynal atria with small shallow annulations, the small and spherical ST, the long, narrow and straight CD.

Description. Male holotype (BE_RMCA_ARA.Ara 247655). Measurements. CL 1.82, CW 1.42, CH 1.28, SL 0.72, SW 0.64, AL 1.48, AW 1.08, chelicera length 0.62, chelicera width 0.34. Legs. I: 1.14, 0.52, 1.00, 0.72, 0.40. II: 0.90, 0.29, 0.60, 0.54, 0.32. III: 1.36, 0.48, 0.78, 0.92, 0.31. IV: 1.08, 0.36, 0.78, 0.98, 0.42. Eyes AME 0.44, ALE 0.22, PME 0.07, PLE 0.12, ORW 1.35. Colouration ( Figs 1, 3, 5 ). Carapace generally dark brown, with lighter patch posterior to fovea, five distinctive spots of white setae arranged in a wide U-shape, white fringe of setae around posterior ventral part of carapace and dense yellowish patch of setae just below AMEs, fluoresce at various parts of carapace; chelicerae orangish-brown; legs brownish, with small patches of white setae throughout, coxae pale both dorsally and ventrally; abdomen generally beige with many long flattened black setae, many patches of white setae including a mostly contiguous white band around lateral midpoint, venter beige with black mottling. Carapace. Very high ( Fig. 3 ), declining sharply just posterior to fovea, foveal depression shallow and circular. Sternum. Broad oval shape, truncated anterior margin ( Fig. 5 ). Legs. Formula 4132, of similar width/ broadness, with F & Ti I slightly broader. Chelicerae. Two teeth on promargin, apical tooth very large and curved dorsally, tusk-like, one tooth on retromargin ( Fig. 5 ), broad triangular. Abdomen ( Figs 1, 3, 5 ). Ovoid, widest at 2/3 rd along length; several longish black hairs protrude at a 45°—30° angle at anterior margin; venter dull. Leg spination. I: F 2, Ti 4-4, Mt 2-2; II: F 2, Ti 2pl 2v 1rlv, Mt 2pl 2-2 2rl (i.e. 2-2-2-2).

Pedipalp ( Figs 7, 8 ). Tibia with fringe of long setae on both prolateral and retrolateral sides, prolateral setae black, retrolateral setae white; RTA claw-like, broad and dorsally curved, arising on dorsal portion of tibia; embolus arising at 9 o’clock position at mid-point of bulb and long, about 1.3x total length of bulb, apical 1/3 part wellsclerotized.

Female paratype (BE_RMCA_ARA.Ara 247655). Measurements. CL 1.60, CW 1.26, CH 1.08, SL 0.60, SW 0.56, AL 1.58, AW 1.38, chelicera length 0.52, chelicera width 0.36. Legs. I: 1.02, 0.36, 0.80, 0.50, 0.36. II: 0.81, 0.33, 0.54, 0.44, 0.32. III: 1.10, 0.40, 0.70, 0.64, 0.30. IV: 1.10, 0.30, 0.78, 0.82, 0.44. Eyes: AME 0.38, ALE 0.20, PME 0.08, PLE 0.22, ORW 1.22. Colouration and general body form all as in male except the following characters. Chelicerae without very large promarginal tooth ( Fig. 6 ), apical tooth about twice the size of small basal tooth, retromarginal tooth largest. One spine on retromargin of pedipalp ( Figs 2, 4, 6 ). Legs generally pale yellowishbrown, abdomen generally pale brownish with abundant black mottling and streaks and setae, complete absence of white setae on abdomen ( Figs 2, 4, 6 ). Leg spination. I: P 1, Ti 4-4, Mt 2-2; II: F x, Ti 2pl 3-4 (plv, rlv), Mt 2pl 2-2 2rl (i.e. 2-2-2-2).

Epigyne ( Figs 9, 10 ). Epigynal region large, twice as long as wide, externally ST clearly visible through translucent and weakly sclerotized integument, integument with weak annulations. Internally with relatively large spherical ST that are situated at posterior 1/4 of epigyne, CD long, thin, and mostly straight.

Figures

FIGURES 1–6. Thiratoscirtus iyomii Pett, sp. nov. 1, 3, 5 male; 2, 4, 6 female; 1, 2 dorsal view; 3, 4 lateral view; 5, 6 ventral view. Scale bars: 1 mm.

FIGURES 7–10. Thiratoscirtus iyomii Pett, sp. nov. genitalia drawings. 7, 8 male pedipalp; 9, 10 female epigyne; 7, 9 ventral view; 8, 10 dorsal view. Scale bars: 0.5 mm.