Monatractides heracles n. sp.

(Figs. 30M, 37A–C, 38A–D)

Type series. Holotype male, dissected and slide mounted, Malaysia, Borneo, Little Lumotok stream, Sayap, Mt Kinabalu, 6º09.467 N, 116º34.027 E, alt. 1069 m asl., 17.ix.2012 Smit.

Diagnosis. Idiosoma large in size (> length 1300 µm) and roundish (dorsal shield L/W ratio 1.2); gnathosomal bay deep, narrow Y-shaped; medial margin of Cx-II/III relatively long; genital field anteriorly enlarged, laterally straight, tapering posteriorly; ejaculatory complex normal in shape (Fig. 30M); palp with thick, pennate setae on P-2 and P-3, distal margin of P-2, P-3 and P-4 medially with several pointed extensions; ventral setae on P-4 thickened and short.

Description

Male. General features —Idiosoma large in size and roundish; frontal plates broad (L/W ratio 1.8), shorter than shoulder plates (shoulder/frontal plate L ratio 1.16–1.2); frontal margin medially slightly convex between flat, anterolaterally directed protrusions (Fig. 37A); Cxgl–4 located far anteriorly, near tips of Cx-I; the tips of Cx-I orientated to the lateral side, gnathosomal bay deep, narrow Y-shaped (Fig. 37C); medial margin of Cx-II/III relatively long; genital field anteriorly enlarged, laterally straight, tapering posteriorly; ejaculatory complex (Fig. 30M) normal in shape (proximal and distal arms and proximal chamber well developed); posterior suture line of Cx-IV distinct, extending posteriorly beyond posterior margin of genital field, medially approaching and parallel to each other; line of primary sclerotization close to posterior margin of genital field; excretory pore and Vgl–2 well separated from the line of primary sclerotization, Vgl–2 posterior to excretory pore; gnathosomal rostrum truncated (Fig. 38D); palp with thick, pennate setae on P-2 and P-3, distal margin of P-2, P-3 and P-4 medially with several pointed extensions (Figs. 38A–B); ventral setae on P-4 short, not reaching the tip of P-5.

Measurements— Idiosoma (ventral view: Fig. 37C) L 1363, W 1067; dorsal shield (Fig. 37B) L 1131, W 944, L/W ratio 1.2; dorsal plate L 1006; shoulder plate L 322–325, W 147, L/W ratio 2.2; frontal plate L 272–277, W 153–158, L/W ratio 1.76–1.78; L shoulder/frontal plate ratio 1.16–1.2. Gnathosomal bay L 253, Cx-I total L 438, Cx-I mL 184, Cx-II+III mL 160; ratio Cx-I L/Cx-II+III mL 2.74; Cx-I mL/Cx-II+III mL 1.15. Genital field L/W 248/194, ratio 1.28; ejaculatory complex L 256; distance genital field-excretory pore 338, genital field-caudal idiosoma margin 497. Gnathosoma vL 204; chelicera total L 237; palp total L 294, dL/H, dL/H ratio: P-1, 39/25, 1.6; P-2, 75/46, 1.63; P-3, 78.5/40, 1.96; P-4, 67/23, 2.9; P-5, 34/14, 2.44; P-2/P-4 ratio 1.1. Legs: dL of I-L-5–6: 126, 100, I-L-6 H 25.4, dL/H I-L-6 ratio 3.9.

Female: unknown

Etymology. Named after Heracles (Ancient Greek: ρακλῆς), who was the greatest of the Greek heroes and a paragon of masculinity. The species name is a noun in apposition (in the nominative case), despite the Recommendation 31A of the ICZN (1999) about avoidance of personal names as nouns in appositions, because there is no case for it being confusing or misleading.

Discussion. The male of Monatractides heracles n. sp. is easily distinguished from other members of the genus due to the combination of a large idiosoma dimensions (> length 1300 µm) and a narrow Y-shaped gnathosomal bay. Further diagnostic features of the new species include the relatively long medial suture line of Cx-II+III, posterior suture line of Cx-IV extending beyond posterior margin of genital field and medially approaching to each other, and by the shape of the palp with thick, pennate setae on P-2 and P-3, distal margin of P-2 and P-3 medially with several pointed extensions and a thickened and short ventral setae on P-4.

Habitat. Sandy/bouldery stream, shaded by rain forest.

Distribution. Borneo; known only from the locus typicus.