Acuclavella makah Richart & Hedin 2013

Description of male. Body arched and convex dorsally (Figure 7), sides parallel with equal scutum and carapace widths; nearly all of body heavily sclerotized, black, with densely scattered hemispherical warts which irregularly house short setae apically or posteriorly. Total length 4.11 mm (n=3; 4.05–4.20 mm), carapace length in midline 1.26 mm (n=10; 1.05–1.44 mm), greatest carapace width 2.57 mm (n=3; 2.50–2.72 mm); length of fused scutes I-V in midline 2.33 (n=10; 2.20–2.48 mm), scutum length in midline 2.74 (n=3; 2.60–2.90 mm) greatest scutum width 2.57 mm (n=3; 2.50–2.72 mm). Eye tubercle at anterior edge of carapace, prolonged anteriad into a sharp conical spine 1.27 mm (n=10; 1.05–1.45 mm) from ventral edge of eye to tip of spine; 1.58 mm above the carapace (n=3; 1.53–1.64 mm). Eyes light-brown to brown, located basally on tubercle. Surface of carapace evenly curved, posterior margin arcuate. Metapeltidial paramedian sensory cones short, acute spines standing 0.19 mm (n=10; 0.13–0.25 mm) above the surface of the metapeltidium, shiny, lacking warts. All scutal areas with pairs of paramedian tubercles. Area I paramedian tubercles cluster of cuticular warts standing 0.04 mm above the surrounding scute (n=10; 0.025–0.075 mm), two additional pairs of warty tubercles reduce in size laterally. Paramedian tubercles of area II rise to form large acute spines standing 1.37 mm above the scutum surface (n=10; 1.13–1.75 mm); lateral to spines a pair of tubercles typically small cluster of warts, though one individual (CHR1536) with lateral pair of short spines. Scute areas III, IV, and V with three pairs of wart-clustered tubercles each; paramedian pair largest, diminishing in size laterally along scute, and posteriorly across scute areas. Paramedian tubercles of area III stand 0.03 mm (n=10, 0.03–0.05 mm) above surface of the tergite; area IV tubercle height 0.04 mm (n=10, 0.03–0.08 mm). Holotype and paratype (CAS) with first free tergite (area VI) with barely distinguishable tubercle as median pair of enlarged warts, tergites VII and VIII without tubercles; paratype (UWBM) tergite VI with median and lateral pair of enlarged warty tubercles, tergite VII with barely distinguishable tubercles, these lacking on tergite VIII. Tergite IX divided, triangular, bracketing tergite X, which forms the anal operculum. Abdominal sternites with infrequent setae; warty sculpturing strongest on posterior and lateral margins; brown to dark brown. Prosomal sternum length 0.14 mm (n=2, 0.13–0.16 mm), width 0.28 mm (0.26–0.30 mm); brown; without setae. Labium weakly sclerotized, wider than long, length 0.08 mm (n=3; 0.05–0.11 mm), width 0.15 mm (0.13–0.17 mm); light brown to yellow-brown, without setae. Palpal endites brown to yellow-brown, large, free, bearing many setae; leg II endite bearing 3 setae in holotype and paratype (CAS), 2 in paratype (UWBM); legs I, III, IV endites without setae. Epistome with horn-like anteriad projection, decurved or slightly decurved, projecting 0.34 mm (n=2, 0.33–0.36 mm) from sulcus. Chelicerae basal article (I) dark brown dorsally, middle article (II) with prolateral and retrolateral striations of darker, more sclerotized striations. Article I length 1.18 mm (n=3, 1.06–1.30 mm), width (I) at widest point 0.41 mm (0.38–0.43 mm), article II length 1.40 mm (1.34–1.46 mm), width (II) at widest point 0.40 mm (0.38–0.43 mm), article III length 0.53 mm (0.50–0.57 mm). Article I with raised, setose glandular area on dorsal surface (Figure 8). Article I with boss-like tubercles proximally on proventrolateral and retrolateral surfaces, one individual with proventrolateral tubercles bilobed; proventrolateral tubercle may function to macerate food or manipulate food items in conjunction with the epistome process. Cleavage of corpus and fixed finger housing 5 or 6 setae on prolateral side of article II; 12 or 15 setae on ventral surface of article II; these patches discrete. Palpal coxae yellow-brown to brown, with two seta-bearing tubercles ventrally (Figure 8). Palpal measurements given in Table 5. Trochanter brown to dark-brown with 3 (holotype) or 4 seta-bearing tubercles; femur white; patella white without dark band medially, with prolateral, distal darkened tubercles; bearing microtrichia and small setae distally; tibia white with scattered setae and dense microtrichia; tarsus white, usually darkening distally. Claw rudiment very small. Acuclavella makah palpus and leg measurements.
Appendage Segment Male Female Mean Range n Mean Range n Palpus trochanter 0.58 0.54-0.62 3 0.57 0.54-0.60 3 femur 0.95 0.90-0.98 10 0.98 0.88-1.05 14 patella 0.67 0.62-0.72 3 0.70 0.67-0.74 3 tibia 0.79 0.73-0.84 3 0.72 0.68-0.76 3 tarsus 0.73 0.71-0.76 3 0.68 0.67-0.68 3 Leg I trochanter 0.57 0.56-0.60 3 0.53 0.50-0.56 3 femur 2.67 2.60-2.72 3 2.46 2.36-2.56 3 patella 0.97 0.92-1.00 3 0.90 0.88-0.92 3 tibia 1.75 1.72-1.76 3 1.57 1.55-1.60 3 metatarsus 2.36 2.24-2.44 3 2.13 2.08-2.20 3 tarsus 2.93 2.76-3.04 3 2.72 2.56-2.80 3 Leg II trochanter 0.60 0.56-0.64 10 0.61 0.56-0.64 14 femur 4.01 3.76-4.35 10 3.85 3.60-4.20 14 patella 1.12 1.00-1.20 10 1.14 1.04-1.28 14 tibia 2.65 2.40-2.88 10 2.64 2.40-2.92 14 metatarsus 3.91 3.60-4.25 10 3.80 3.52-4.75 14 tarsus 5.11 4.55-5.50 10 4.62 4.25-4.94 14 Leg III trochanter 0.55 0.52-0.56 3 0.57 0.55-0.60 3 femur 2.47 2.32-2.56 3 2.21 2.12-2.32 3 patella 0.93 0.92-0.96 3 0.96 0.88-1.05 3 tibia 1.64 1.60-1.68 3 1.60 1.52-1.65 3 metatarsus 2.64 2.56-2.76 3 2.48 2.40-2.64 3 tarsus 3.16 3.00-3.32 3 2.95 2.85-3.12 3 Leg IV trochanter 0.67 0.60-0.72 3 0.65 0.60-0.72 3 femur 3.64 3.52-3.80 3 3.34 3.16-3.60 3 patella 1.05 0.96-1.12 3 1.11 1.04-1.20 3 tibia 2.32 2.32 3 2.30 2.16-2.44 3 metatarsus 4.16 4.05-4.30 3 3.99 3.76-4.25 3 tarsus 4.17 3.85-4.35 3 3.86 3.68-3.95 3 All measurements in millimeters; n= sample size Leg measurements given in Table 5. Trochanters, femora, patellae, tibiae black, lighter at joints, with scattered, distally elevated scales which subtend short setae, scales occasionally house setae apically or posteriorly. Metatarsi of leg III with proximal half black or darkened; leg IV proximal three-quarters black or darkened; legs I and II with proximal end darkened; remaining metatarsal areas pale-brown to yellow-brown. Scaled-microsculpture subequal to darkened areas. Metatarsi and tarsi without tubercles. Six of ten males with false leg articulations on metatarsi of leg II, including holotype. Leg claws single, black, not toothed, evenly curved. Penis 2.39 mm in length (n=2, 2.38–2.40 mm); glans plate length 0.34 mm (n=2, both 0.34 mm); stylus length 0.16 mm (0.14–0.17 mm). Shaft evenly tapered, broadening slightly at glans; glans with scattered small setae; stylus spirally twisted, very slightly decurved. Description of female. Similar to male for nearly all characters. Total length 5.14 mm (n=3; 5.00–5.31 mm); carapace length 1.37 mm (n=14; 1.25–1.81 mm); carapace width 3.16 mm (n=3; 3.00–3.31 mm); scutum length 3.82 mm (n=3; 3.63–3.94 mm); scutum width 3.33 mm (n=3; 3.19–3.50 mm); length of fused sternites I-V 2.96 mm (n=14; 2.75–3.19 mm). Eye tubercle height above surface of carapace 1.37 mm (n=3; 1.31–1.46 mm); distance from ventral surface of eye to tip of spine 1.21 mm (n=14; 1.08–1.33 mm). Eye color brown. Metapeltidial spine 0.16 mm (n=14; 0.10–0.23 mm). Paramedian tubercles of tergite I height 0.06 mm (n=14; 0.03–0.10 mm) above surface of tergite. Tergite II paramedian tubercles greatly enlarged spines standing 1.10 mm (n=14; 0.93–1.28 mm) above tergite surface; tubercles lateral to spines warty mounds. Paramedian tubercle height of tergite III 0.07 mm (n=14; 0.05–0.10 mm); IV 0.06 mm (n=14; 0.03–0.08 mm). Tergites III, IV, V with three pair of tubercles with median pair largest, reducing in size laterally along tergite and posteriorly across tergites; the right median tubercle of tergite III of paratype (CAS) enlarged into mound with diminished frequency of warts standing 0.22 mm above carapace. First free tergite (IV) with median and lateral pair of enlarged warty tubercles, or barely distinguishable median pair of enlarged warts; tergite VII without tubercles, or tubercles barely distinguishable, or more noticeable; tergite VIII without distinguishable tubercles. Sternites brown. Prosomal sternum length 0.17 mm (n=2, 0.17–0.18 mm), width 0.32 mm (0.30–0.33 mm); dark brown. Labium wider (0.17 mm, 0.16 mm, 0.14 mm) than long (0.09 mm, 0.09 mm, 0.14 mm), or nearly equal; yellow-brown to light brown. Palpal endites brown, yellow-brown, or light brown. Paratypes (AMNH, CAS) with 3 setae on leg II endite; paratype (UWBM) with 2 setae. Horn-shaped process of epistome decurved or projecting downward; length 0.48 mm (n=2, 0.47–0.50 mm). Chelicerae article I length 1.35 mm (n=3; 1.20–1.47 mm), width 0.45 mm (n=3, 0.44–0.46 mm); article II length 1.49 mm (n=3; 1.48–1.50 mm), width 0.42 mm (0.42–0.43); article III length 0.59 mm (n=3; 0.56–0.60 mm). Article I without raised glandular mound (Figure 8); prolateral side of cheliceral article II with 2 or 4 setae at cleavage of corpus and fixed finger; 12 setae on ventral surface of article II; these patches discrete. Palpus dimensions in Table 5; coxae brown with two seta-bearing tubercles; trochanter brown to dark brown with 4 seta-bearing tubercles; only paratype with tubercle on patella. Leg measurements given in Table 5. Leg trochanters, femora, patellae, and tibiae black, lighter at joints; metatarsi of leg III with proximal half black or darkened, leg IV with proximal three-quarters black or darkened, proximal end of legs I and II black or darkened, remaining metatarsal areas yellow-brown or pale brown; tarsi yellow-brown or pale brown, darkening distally. Ovipositor length 0.74 mm (n=2, 0.72–0.77 mm), width 0.46 mm (0.44–0.47 mm); furca without dorsoventral differentiation; corona of setae at furcal base surround lobes; apical setae on lobes.

Known from the northwest areas of the Olympic Peninsula in Clallam and Jefferson Counties, Washington State (Appendix I). Found in coniferous or riparian forests along small, perennial water-features such as headwater streams, springs, and seeps; underneath woody debris and moss.