Melanesotypus guadal, Raven, 2015

Melanesotypus guadal View in CoL sp. nov.

( Figs 14a–f View FIGURE 14 , 15a–f View FIGURE 15 . Map 3)

Material. Solomon Islands: holotype ♂, paratype (allotype) ♀, Guadalcanal, Mt Austen , [9°29’S, 159°59’E], 13 Nov 1964, P. Greenslade, BMNH GoogleMaps .

Diagnosis. Melanesotypus guadal differs from Sphecotypus birmanicus ( Thorell, 1897) in the much less constricted eye region of the carapace ( Fig. 14e, f View FIGURE 14 ), the broader embolus tip ( Fig. 15b View FIGURE 15 ) and the presence of a paracymbial spine ( Fig. 15b–d View FIGURE 15 ).

Etymology. The species epithet is a noun in apposition from the type locality.

Description. Holotype male BMNH

Carapace 3.92 long, 1.60 wide. Abdomen 2.56 long, 1.76 wide. Total length 6.5.

Colour: carapace uniformly dark brown; abdomen shiny black; leg I black basally, rest yellowish; legs II–IV faded black; ventrally, sternum, coxae and abdomen black. Carapace: strong saddle basally with long sharply defined caput for ca. 1/3 length of carapace. Cuticle with fine points (as in Fig. 14b View FIGURE 14 ) along edges. Thoracic region domed medially, fovea absent. Posterior margin strongly constricted from coxae IV, with gradual slope. Eyes: occupy ca. 0.5 width of head in broad spaced group. Eight eyes in two recurved rows. AME>ALE>PME>PLE. AME ca. 1.5 x diameter of ALE, and ca. 1 diameter apart and clypeus = AME diameter. PME ca. 3–4 of their diameters apart. Back row much wider than front. Chelicerae: small, vertical; fangs short, transverse. Maxillae: long with outer edge broadly concave, forming Clubiona -like maxillae, labium longer than wide. Sternum: very long, narrow, deeply indented for each coxa. Long cylindrical sclerotised pedicel. Legs: I and II distinctly thinner than III and IV. Scopula absent but ventral tarsi with dense cover of thick setae. Claw tufts dense, enclosing claw. Tarsal trichobothria of similar length for distal half and, with metatarsal trichobothria, all short, recurved. Femora I and II bulbous basally, 2–3 times thicker than distally. Pair of preening combs ventrally on distal metatarsi IV. Spines: all close to leg (obliquely angled) and weak. I: fe p1; ti v2.2; me v2.2. II: fe 0; ti v2.2; me v2.2. III: fe p2 as distal pair; r1; pa 0; ti p2r2v1.2; me p3d1 distal r3v2.2.2. IV: fe d2 as distal pair d1r1; pa 0; ti p2r2v2.2.2; me p3r3v2.2.3. Palp fe d2; pa p1d1; ti p1 + retrolateral line of bristles. Palp: short, tibia without ventral groove; RTA absent; cymbium short with distodorsal scopula; complex folded paracymbial spine plate retrobasally ( Fig. 15b–d View FIGURE 15 ); bulb with long vertical folded spermatic duct ( Fig. 15b View FIGURE 15 ); bulb constricts predistally with wide pre-embolic ridge, broad thick tapered embolus sweeps across ridge. Abdomen: with full scute; tracheal scute broad, transverse but small; weak genital scute.

Allotype Female as male, except:

Carapace 4.40 long, 1.92 wide. Abdomen 3.12 long, 2.88 wide. Total length 7.4.

Colour: femur I ventrally pallid, II with two long bands dorsolaterally, I and II generally darker. Carapace: shallow depression on anterior face of thoracic dome, caput dome much lower; margin serrate. Chelicerae: short, vertical, not projecting forward, dense group of black fang setae; dentition 2R, 2P; boss very small. Labium: strong precoxal triangles; intercoxal triangle extends up to but not fused to carapace on I/II, II/III and III/IV; widest point at coxae II, with strong narrowing and indentation at each coxae; short ridge between coxae IV not fused to pedicel. Pedicel: with long sclerotised cylinder bearing lateral keels and medial keel; only short gap, ca. 1/10 length of pedicel ring, to leading edge of genital scute. Legs: RCH not evident; scopula absent; trichobothria longer on tarsi subcentrally; claw tufts high, dense; ventral tarsi and metatarsi with thick, obliquely set hairs. Spines: I: fe p1d1; ti v.2.2. II: fe p1d1; ti v2.2; me v2.2. III: fe 3 on distal edge; pa d1; ti p2r2v2.2 (bs); me p3r3v2.2.3. IV: fe 3 on distal edge; pa d1; ti p2r2v2.2.2; me p3r3v2.2.3. Palp: fe d1; pa p1d1; ti p2d1; ta p2 basal. Palp: emerges well back off front edge of carapace; tarsus pre-apically incrassate then tapers to short blunt point, claw distinct, dentate. Abdomen: short, spherical; large subcircular shiny dorsal scute extends for 3/4 length and slightly onto lateral faces, without feathery hairs, light pile of very fine hairs; genital scute without collar; post-epigastric sclerites short. Translucent, triangular small colulus present. Tracheal scute a wide ovoid zone with rounded medial ridge. Epigyne: a distinctly raised mound with small lateral fossae, without paragenital brackets. Spinnerets: all short; 3 large spigots on PMS, 2 on PLS.

Distribution and habitat. Known only from rainforest at Mt Austen, Guadalcanal, Solomon Islands.