Psednocnemis davidgohi West, Nunn & Hogg, 2012, sp. nov.
Creators: name: West, Rick C.
name: Nunn, Steven C.
name: Hogg, Stephen
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Theraphosidae
Psednocnemis
Psednocnemis davidgohi

description: Psednocnemis davidgohi sp. nov.
(Figs 1–27, 39)
Coremiocnemis hoggi (in part: male) West & Nunn 2010: 28, figs 112–118.
Etymology: A patronym in honour of Mr. David Goh for his help and support with our research over the past decade in West Malaysia.
Types: female holotype QM S88303, Fraser’s Hill [3°42'N, 101°45'E], Selangor, West Malaysia; female paratypes QM S88306, QM S88313, QM S88074 and QM S88075, Fraser’s Hill [3°42'N, 101°45'E], Selangor, West Malaysia, R. C. West and S. Hogg col., Sept. 7, 2009, QM.
Coremiocnemis hoggi, paratype male QM S88022, Fraser’s Hill [3°42'N, 101°45'E], Selangor, West Malaysia, QM.
Diagnosis: P. davidgohi sp. nov. females differ from all other Psednocnemis species in possessing female bilobed spermathecae with lateral lobes mildly shorter than medials, and in extremely thick build of largest lyrate bacillae. P. davidgohi sp. nov. females also differ from P. brachyramosa comb. nov. and P. jeremyhuffi comb. nov. in possessing paddleform lyrate bacillae and from P. gnathospina comb. nov. in <45 intercheliceral pegs. Males differ from all other male Psednocnemis in having distally pointed lyrate bacillae (West & Nunn 2010b, fig. 102).
Description: Female holotype QM S88303. Body length: 49.88.
Carapace (Fig. 2): length 20.61, width 16.91 (width across anterior edge 11.34). Fovea 3.21 wide, procurved, deep, not as wide as OT. Distance from anterior carapace to fovea, 14.94. Carapace with 4 discernible hair types (C1 to C4): type C1 long, needleform pallids border carapace entirely: type C2 long brown spiniforms, located along posterior carapace border only: type C3 short, thin wavy pallids, forming basis of carapace mat: type C4 emerge from what look to be bothrial collars, largely spiniform, pallid, aligned in uniform arrangement: (>9) along anterior edge of each radial groove, (>7) along anterior edge of each thoracic groove, (>5) along anterior edge of each caput groove and a line of>3 along medial caput ridge (between OT and fovea).>3 more behind each side of the OT, nearest median caput row.
Eyes (Fig. 3): ocular tubercle; length 1.75, width 3.25. Anterior row straight. Posterior row slightly recurved. Eyes: AME 0.51/0.52, ALE 0.48/0.22, PLE 0.46/0.22, PME 0.41/0.22. Inter–ocular distances: AME–AME 0.51, AME–ALE 0.61, AME–PME 0.41, ALE–ALE 2.49, ALE–PME 0.44, PME–PME 1.71, PME–PLE 0.19, PLE– PLE 2.76, ALE–PLE 0.26. OT hair types: 16 to 20 C4’s directly posterior to AME’s and PME’s. OT entirely covered in short weak, pallid setae (C3), directionally point to centre of OT, posteriorly and anteriorly. Lateral small pallids (C3) very sparse with no uniform direction/random point.
Chelicerae (Figs 10–11): length 11.99, width at base of each lobe 5.35 (bases widest point, dorsally). Retrolateral lyrate region (Fig. 12): a series of strikers (>80), in>7 horizontal rows (rows unordered). Strongest/ longest strikers on lowest rows. Each striker needleform, with some filiform ends. Teeth 12 larger,>120 proximomesals. Intercheliceral pegs (>10 larger: 0.26–0.52 long,>27 smaller) in tight cluster on proximodorsal surface (Figs 14, 16). Retrolateral face proximomedially with 1 short but strong spine (0.47 long) and>6 strong spiniform setae (Fig. 15), distad.
Maxillae (Fig. 8): prolaterally plano-convex, anterior lobe well pronounced, many cuspules (> 90) on inner proximoventral surface. Lyra (Fig. 9): many bacilliform rods (>90 larger,>150 smaller) form dense, ovoid patch prolaterally (3.35 long, 1.95 high), lowest row with>15 bacillae, longest rods in centre of lowest row. Rods paddleshaped (paddles up to 0.40 long) medium shafts (length including paddles up to 0.63), largest without distal blades (very thick and powerful ca. congeners). At widest point, lyrate patch 10–12 rows deep, smallest rods dorsally. Proximal end of patch truncate, distal end mildly pointed. Dorsal to maxillary suture> 30 small spines (Fig. 8) on distal margin of maxillae, rows unordered.
Labium (Fig. 4): length 3.44, width 4.51, many small cuspules (>600) along anterior 1/4 surface. Two hair types on labium (L1, L2), L1: long, reasonably dark spiniform in shape, curving distally toward anterior, most concentrated along lateral borders. Setae longest along anterior edge. L2: short dark spiniforms, similar morphology to L1, but half size.
Sternum (Fig. 5): length 8.99, width 4.47. Slightly wider posteriorly than anteriorly, with 5 discernible hair types (S1 to S5): type S1 longest, thickest, darker basally, becoming pallid distally, entire but sparse over sternum: type S2 elongate spiniforms, entirely dark, border sternum, most concentrated posteriorly: type S3 with same morphology as S1, although only 1/4–1/2 length by comparison, entire but sparse over sternum: type S4 short thin pallids, forming basis of sternal mat: type S5 elongate filiforms bordering sternum, most concentrated posteriorly. Posteriorly between left and right cox. IV, sternal border acuminate, lateral sternal points also acuminate. Sternal sigilla (Fig. 5): 3 pairs (not including labio-sternal sigilla), posterior medium in size; right length 1.36, width 0.35, left length 1.36, width 0.34, ovoid, 2.4 apart, 1.65–1.68 from sternal margin. Median pair 1/3 size of posterior, similar in form, 0.45–0.61 from sternal margin. Anterior pair quarter size of posterior, somewhat obscured, border sternal margin. Labio-sternal sigilla large, as big as PSS, 1.25 apart.
Leg setation: All longer leg setation curves distad, lengths of specimen longer tibial setae: palp 0.79, I 0.85, II 0.74, III 0.75, IV 0.94. Lengths of specimen longer metatarsal setae: I 1.08, II 0.97, III 0.98, IV 1.21. Tibia and metatarsi IV with most setae (met. IV ca. 12X met. I). All femora covered in short dark setae that form the setal mat, with many long distally curving pallids, most concentrated ventrally.
Legs: formula (length); IV, I, II, III: (width) I, II, III, IV. Leg RF ~94.74. Leg lengths (fem., pat., tib., met., tar., total): palp: 11.19, 6.72, 8.17, 0.00, 7.02, 33.10. I: 15.58, 10.79, 11.92, 9.35, 6.76, 54.40. II: 13.23, 8.89, 9.60, 9.56, 5.69, 46.97. III: 12.79, 7.19, 7.68, 9.11, 5.94, 42.71. IV: 16.74, 7.98, 11.88, 14.6, 6.22, 57.42. Leg mid–widths (fem., pat., tib., met., tar., total.): palp: 2.97, 3.01, 3.15, –, 2.15, 11.28. I: 3.78, 3.55, 3.63, 4.04, 3.54, 18.54. II: 3.75, 3.42, 3.42, 3.41, 2.74, 16.74. III: 3.91, 3.62, 3.27, 2.76, 2.39, 15.95. IV: 3.69, 3.64, 3.2, 2.29, 2.67, 15.49. Tar. IV with transverse weakening, most obvious from lateral views.
Scopula: met. and tar. I–III undivided, met. and tar. IV divided by several rows of long, straight spiniform setae (Fig. 20). Met. I: entire, II: 4/5, III: 3/4, IV: 1/4. Tar. IV without wider /incrassate retrolateral scopulate field than seen prolaterally. Met. I–III with dense scopula, setae long, met. IV not as dense, scopula sparse.
Coxae (Figs 5, 23): many small black thorns prolatero-dorsally, some thorns retrolaterally on I–III. Coxae easily seen dorsally. I longest, ca. 1.2 times length of II. IV widest, basally rectangular with rounded corners. Coxae with small patch of dorsoprolateral thorns on I–IV. I–III ventrally with many long thick blunt setae proximally, dark in color. Sparse mid-length black setae found evenly over ventral surfaces. IV with mixture of long thick blunt setae entirely, pallid intermixed with shorter thin pallid setae. Ventral I–IV gently sloping anteriorly. Retrolateral setation: I–III with median narrow light brush, grading to spiniform setae dorsally. IV with distodorsal brush, setae long, spiniform. I–IV retrolaterally lack ventral ledge. Ventral measurements for coxae: palp–length 8.43, width 4.83; I– 9.12, 4.78; II– 7.55, 4.59; III– 6.56, 4.33; IV– 7.28, 4.86.
Trochantera: palp–length 2.11, width 3.14; I– 4.13, 4.42; II– 4.06, 4.09; III– 3.78, 4.23; IV– 3.61, 4.22.
Trichobothria: Tarsi: on all tarsi proximal filiform field slightly wider than clavate field, merges evenly. Clavates on tar. I in proximal 2/3 (>30), long filiforms only in proximal half, shorter filiforms intermixed with clavates distally. Clavate extent on tar. II–IV cf. I, in distal 2/3. Shorter filiforms for length (following Raven 2005). Short epitrichobothrial field on tar. I shorter than clavates, uniform height for length. Tarsal organ evident on legs I–IV under stereoscope (up to 50X), organ domed. Tar. I with field 0.82 long, 0.16 wide distally, 0.23 wide proximally. Tar. IV with field 0.83 long, 0.11 wide distally, 0.19 proximally. Metatarsi: trichobothrial field not detected. Tibia: Tib. I prolaterally and proximally with short, possibly clavate trichobothria (>12 per 0.2 mm squared) with patch 0.87 long, 0.94 wide, clearly pallid:>8 filiforms detected in semicircular pattern proximally to clavate patch. Tib. IV prolaterally and proximally with short clavates (>9 per 0.2 mm squared) with patch 1.15 long and 1.21 wide:>9 filiforms detected in semicircular pattern ventrally to clavate patch.
Spines: right met. I with 1 DV (left absent), met. II with 1 DV, 1 DRV, met. III (right) with 1 DV, 1 DPV, 1 DRV, (left) with 1DV, 1 DRV, 1 DPD, 1 DD, met. IV with 2 DV, 1 DPV, 1 DRV, 1 DPD, 1 DD.
Claws: paired claws on all legs and palpal claw unarmed. Reduced third claw present on leg IV.
Abdomen (Fig. 7): 21.76 long, ovular, elongated, yellow brown (in alcohol), with 4 discernible hair types (A1 to A4): Dorsally with 3 hair types: type A1 long, dark, but distally pallid: type A2 mid-length, also dark, but distally spiniform: type A3 form dense mat of abdomen, mid-length, but not spiniform. Longest hairs (A1) more concentrated posteriorly toward spinnerets, distad. Ventral hair types similar to dorsal, although types A2, A3 more dense entirely. Hair type A 4 in very sparse patch (1.08 length, 1.15 width), trapezoid-shaped, immediately posterior to pedicel between median regions of cox. IV. Hairs medium length, wavy, pallid.
Genitalia: epigastric fold 3.14. Spermathecae (Fig. 6): paired but not fused, separated by 0.45 (width including spermatheca 2.05), bilobed (basally dividing), each lobe with apical rounded ends (lateral bulbs strongest), not apically swollen: lateral bilobe apical widths 0.23 (left)– 0.25 (right): medial bilobe apical widths 0.2 (left)– 0.17 (right), sclerotization heaviest apically, gradually decreasing basally. Lateral lobes (including shaft length) not as long as medials (laterals 0.96–medials 1.23). Epigastric fold extends ca. 2/3 length of medial spermathecal lobes.
Spinnerets: PMS: length 2.93, width (medially) 1.08. PLS: section lengths; proximal 4.27, medial 3.4, distal 3.57. PLS section widths (medially); proximal 1.63, medial 1.34, distal 1.17. Spinnerets with 2 discernible hair types (SP1, SP2): SP1 very short and distally blunt pallid, covers both pairs ventrally, second form (SP2), very similar but up to two times longer, dorsally on all segments.
Color (in life, Fig. 1) post and mid moult; chelicerae, carapace and abdomen dorsally chocolate brown with violet hues, coxae and trochantera slightly paler: darker ventrally. Femora I–IV dark violet, pat., tib., met. and tar. I bright cinnamon, pat., tib., met. and tar. II pallid cinnamon, pat., tib., met. and tar. III and IV mildly paler than femora, similar color; premoult: orange brown entirely, femora slightly darker.
Distribution and natural history: To date, all specimens (known to the authors) of P. davidgohi sp. nov. have come from the summit and south-western slopes of Fraser’s Hill, Selangor, West Malaysia, at approximately 1150 meters in elevation (Figs 24, 27). It is a fossorial theraphosid that constructs its burrow retreat in steep sloped ground in shaded areas of montane tropical rainforest. Depending on the size of the specimen, burrows were found to range 25–90 cm in depth and to be a simple, self-excavated, unsilk-lined, tunnel that terminated in an enlarged flask-like chamber. The soil was moist and clay-like soil. The burrow opening consisted of an unflared and poorly silken collar, usually cryptic amongst low mosses (Figs 25, 26). Psednocnemis davidgohi sp. nov. was found living sympatrically with Coremiocnemis hoggi West & Nunn 2010 and Psednocnemis jeremyhuffi (West & Nunn 2010), sometimes as close as 70 cm. The species were found in the lower region of sloped embankments and in areas that were denser in root fibers and mosses (R. West and S. Hogg, pers. obs.). Although Peninsular Malaysia is monsoonal, it has two more noticeable monsoon seasons: February to May and August to December. Males have been found between the months of September and November, during the onset of the monsoons.
description: Published as part of West, Rick C., Nunn, Steven C. & Hogg, Stephen, 2012, A new tarantula genus, Psednocnemis, from West Malaysia (Araneae: Theraphosidae), with cladistic analyses and biogeography of Selenocosmiinae Simon 1889, pp. 1-43 in Zootaxa 3299 on pages 16-22, DOI: 10.5281/zenodo.280919