Etymology: The specific epithet is a patronym honoring Dr Ansie Dippenaar-Schoeman of the Agricultural Research Council, Plant Protection Research Institute, South Africa, for her many contributions to African arachnology.

Diagnosis: Uroplectes ansiedippenaarae sp. n. appears to be most closely related to U. variegatus (Fig. 2F) but differs from the latter in the following respects: Uroplectes ansiedippenaarae sp. n. is smaller, total length 16.2–19.4 mm (n = 11) in both sexes, than U. variegatus, total length 19.1–22.4 mm (n = 6) in ♂ and 21.8–25.9 mm (n = 6) in ♀ (Tables 1, 2). The habitus of U. ansiedippenaarae sp. n. is more robust, with an incrassate pedipalp chela manus and a globose telson (Fig. 2C–E), than that of U. variegatus, which is more gracile, with a slender chela manus and telson (Fig. 2F). The number of subrows in the median denticle rows of the pedipalp chela fixed and movable fingers is lower (7 and 8, respectively; Table 1) in U. ansiedippenaarae sp. n., than in U. variegatus (8 and 9, respectively; Table 2). The pectinal tooth count is also lower, with 12–14/12–14 (n = 10) (♂) and 11/13 (♀), and the basal pectinal tooth of the female much smaller (ca. twice the size of the other teeth) in U. ansiedippenaarae sp. n., than in U. variegatus, with 15–18/16–18 (n = 6) (♂) and 14–15/14–16 (n = 6) (♀) pectinal teeth and the basal pectinal tooth of the female ca. five times larger than the other teeth (Tables 1, 2). Uroplectes ansiedippenaarae sp. n. is generally less granular, with less developed metasomal carinae than U. variegatus. For example, the spiniform granules on the dorsosubmedian carinae of metasomal segments I–III and, especially, IV, are small, the ventrosubmedian carinae of segments I–IV and the ventrolateral carinae of segment V obsolete, and the primary subaculear tubercle rounded in U. ansiedippenaarae sp. n., whereas the spiniform granules on the dorsosubmedian carinae of metasomal segments I–IV are prominent, the ventrosubmedian carinae of segments I–IV and the ventrolateral carinae of segment V distinct and costate-granular, and the subaculear tubercle conical in U. variegatus. The two species differ further in the pattern of infuscation. The legs and pedipalps are immaculate, except for the pedipalp chela fingers, in U. ansiedippenaarae sp. n., whereas the leg femora and patellae and the pedipalp femur, patella, chela fingers and often the manus are spotted with infuscation in U. variegatus. Metasomal segments I–III, and often segment IV are immaculate in U. ansiedippenaarae sp. n., whereas the metasomal carinae and often the dorsomedian surface of metasomal segments I–IV are striped with infuscation in U. variegatus. The mesosomal tergites of U. ansiedippenaarae sp. n. bear at most three stripes of infuscation (a median stripe and usually a pair of lateral stripes; Fig. 2C–E), whereas the tergites of U. variegatus bear at least five stripes of infuscation (a median stripe, a pair of submedian stripes and one or two pairs of lateral stripes; Fig. 2F).

Description: The following account is based on the type material.

Total length: Adult: small, maximum length, measured from anterior margin of carapace to tip of aculeus, 18.2 mm (16.2–19.4 mm, n = 6) (♂), 17.3 mm (♀) (Table 1).

Colour: Base colour uniformly pale yellowish to reddish orange (Fig. 2C–E), with paler sternum, genital operculum, pectines, sternites, telson and ventral surface of legs. Uniformly immaculate except for infuscation as follows: Pedipalp chela fingers infuscate; cheliceral manus, retrolateral surfaces usually infuscate; some or all carapace surfaces (notably interocular, circumocular, anterolateral, median lateral, posteromedian and posterolateral) with patches of infuscation; mesosomal tergites with a median stripe and usually a pair of lateral stripes of infuscation (Figs 2C–E, 4); metasomal segment IV and, to a much lesser extent, segment III with ventromedian stripe, pair of ventrolateral stripes and sometimes pairs of lateral and/or dorsolateral stripes of infuscation; segment V entirely infuscate, except posteriorly. Dark, infuscate metasoma V contrasts with paler carapace, pedipalps, legs and metasomal segments I–IV, and very pale telson.

Chelicerae: Movable finger, ventral surface with two subdistal teeth; distal external (dorsal) and distal internal (ventral) teeth subequal, opposable. Fixed finger, ventral surface without denticles. Fingers and manus, proventral surfaces with long, dense vestiture of macrosetae.

Carapace: Anterior width of posterior width, 46 % (42–50 %, n = 10) (♂), 36 % (♀); posterior width of length, 100 % (95–105 %, n = 10) (♂), 100 % (♀) (Table 1). Anterior carapace margin slightly procurved, with median projection (epistome) and without median notch (Fig. 3A, B). Five pairs of lateral ocelli (Type 5 pattern); each lateral ocular tubercle with three major ocelli, situated laterally, and two minor ocelli, situated posterior and posterodorsal to the posterolateral major ocellus. Median ocelli considerably larger than lateral ocelli, distance between ocelli less than width of ocellus. Median ocular tubercle situated anteromedially, distance from anterior carapace margin 33 % (28–37 %, n = 10) (♂), 33 % (♀) of carapace length (Table 1). Superciliary carinae obsolete, finely granular, not protruding above median ocelli. Other carinae absent. Anteromedian sulcus shallow, narrow; posteromedian sulcus narrow, shallow anteriorly, becoming deeper posteriorly; posterolateral sulci shallow, wide, curved; posteromarginal sulcus obsolete. Carapace surfaces finely and sparsely granular.

Pedipalps: Femur width of length, 40 % (33–43 %, n = 10) (♂), 38 % (♀) (Table 1). Prodorsal, promedian, proventral, retrodorsal and retromedian carinae obsolete, granular, complete (Fig. 5A). Promedian carina additionally with a few subspiniform granules. Other carinae absent. Dorsal and prodorsal intercarinal surfaces finely and sparsely granular. Other surfaces smooth or nearly so. Patella width of length, 42 % (40–44 %, n = 10) (♂), 41 % (♀) (Table 1). Promedian and proventral carinae obsolete, comprising discontinuous rows of spiniform granules, and demarcated with prominent macrosetae, especially proximally (Fig. 5B–D). Other carinae absent. Prodorsal intercarinal surfaces finely and sparsely granular. Other surfaces smooth or nearly so. Chela manus slightly incrassate (♂, Fig. 5E–G) or slender (♀, Fig. 5H); width of height, 114 % (113–150 %, n = 10) (♂), 114 % (♀); width of length along ventroexternal carina, 62 % (56–64 %, n = 10) (♂), 62 % (♀); length along ventroexternal carina of length movable finger, 90 % (81–100 %, n = 10) (♂), 81 % (♀) (Table 1). Manus sparsely setose; surfaces acarinate, smooth (Fig. 5E–H). Fixed and movable fingers sublinear, little to no gap between fingers proximally, when closed (Fig. 5F, H); surfaces smooth; median denticle rows respectively comprising seven and eight oblique denticle subrows (Table 1), each subrow terminating in a large median denticle proximally, and flanked proximally by a large retrolateral denticle, and distally by a larger prolateral denticle, prolateral denticles separated from median subrows by approximately one denticle width; fingers each with enlarged terminal denticle.

Trichobothria: Orthobothriotaxic, Type A, α-configuration (Fig. 5) with the following segment totals: 11 femur: 5 dorsal (d ₁–d ₅), 4 internal (i ₁–i ₄), 2 external (e ₁, e ₂); 13 patella: 5 dorsal d ₁–d ₅, 1 internal (i), 7 external (et, est, em, esb ₁, esb ₂, eb ₁, eb ₂); 8 chela manus: 2 ventral (V ₁, V ₂), 6 external (Eb ₁–Eb ₃, Esb, Est, Et); 7 chela fixed finger: dt, db, it, et, est, esb, eb. The following trichobothria are noticeably smaller (‘petite’): femur: d ₂, d ₃, d ₄, i ₄, e ₂; patella: d ₂, eb ₂; chela manus: V ₁, Et, Eb ₃, Esb; chela fixed finger: esb.

Legs: Femora I–IV, each with two obsolete granular carinae and retrolateral surfaces finely and sparsely granular. Patellae I–IV, retrolateral surfaces finely and sparsely granular. Other segments acarinate and smooth. Tibiae I–IV, retrolateral and ventral surfaces with scattered macrosetae; III and IV with spurs. Basitarsi I–IV, each with pro- and retroventral rows of fine, acuminate macrosetae; macrosetal combs absent; pro- and retrolateral pedal spurs present. Telotarsi I–IV, each with pro- and retroventral rows of fine, acuminate macrosetae; laterodistal lobes truncated; median dorsal lobes extending to ungues; ungues short, distinctly curved, equal in length.

Sternum: Subtriangular (Fig. 3C, D). Median longitudinal furrow Y-shaped, shallow anteriorly, becoming deeper posteriorly.

Genital operculum: Genital opercula suboval, completely divided longitudinally; genital papillae present (♂, Fig. 3C), absent (♀, Fig. 3D).

Hemispermatophore: Flagelliform.

Pectines: Distal edge reaching past distal edge of coxa IV but not reaching to distal edge of trochanter IV (♂, Fig. 3C) or to distal edge of coxa IV (♀, Fig. 3D). Three marginal lamellae and 7 or 8 (♂) or 6 (♀) median lamellae; first proximal median lamella (scape) of each pecten unmodified, mesial margin angular, approximately 90º, teeth present along entire posterior margin. Fulcra present. Pectinal teeth curved, all similar in size (♂) or basal pectinal tooth oval, enlarged, approximately twice the size of other teeth (♀); tooth count, 13/13 (12–14/12–14, n = 10) (♂) and 11/13 (♀) (Table 1).

Mesosoma: Tergites I–VI unicarinate, each bearing costate to costate-granular median carinae in posterior half to two-thirds of segment and pair of submedian depressions. Tergite VII pentacarinate, with obsolete median carina, restricted to anterior half of segment, distinct costate-granular submedian carinae in posterior half, and distinct costate-granular lateral carinae in posterior two-thirds. Pre-tergites smooth. Post-tergites, intercarinal surfaces sparsely and finely granular, becoming more coarsely granular posteriorly. Sternites III–VII, acarinate, smooth, except for sternite VII, which is finely and sparsely granular posterolaterally; IV–VI, each with paired longitudinal depressions prolateral to spiracles, absent on VII. Sternite VII, length of width, 61 % (50–72 %, n = 10) (♂), 56 % (♀) (Table 1).

Metasoma and telson: Metasomal segments I–V progressively increasing in length but similar in width (Figs 4, 6); segment V, width of segment I, width, 90 % (82–100 %, n = 10) (♂), 82 % (♀) (Table 1). Metasoma slender, width of length, segment I, 77 % (71–85 %, n = 10) (♂), 85 % (♀); II, 63 % (56–67 %, n = 10) (♂), 71 % (♀); III, 56 % (56–63 %, n = 10) (♂), 67 % (♀); IV, 47 % (45–52 %, n = 10) (♂), 56 % (♀); V, 43 % (35–48 %, n = 10) (♂), 45 % (♀). Telson vesicle, width of metasomal segment V, width, 89 % (80–90 %, n = 10) (♂), 100 % (♀); globose, height of length, 60 % (53–64 %, n = 10) (♂), 60 % (♀); dorsal surface sublinear, concave basally, ventral surface markedly curved. Aculeus relatively short and abruptly curved, length of vesicle length, 45 % (40–58 %, n = 10) (♂), 47 % (♀). Length metasoma and telson, of total length, 49 % (46–50 %, n = 10) (♂), 46 % (♀). Dorsosubmedian carinae, segments I–IV distinct, costate-granular, complete, each terminating posteriorly in prominent spiniform granule, less pronounced on IV than on I–III (Fig. 6A, B); segment V, absent. Dorsolateral carinae, segments I–IV, distinct, costate-granular, complete, terminating posteriorly in prominent spiniform granule on segments I–III; segment V, obsolete or absent. Median lateral carinae, segments I–III, distinct, costate-granular, complete on I, partial, restricted to posterior three-quarters, on II and III (Fig. 6C, D); segments IV and V, absent. Ventrolateral carinae, segments I–IV, distinct, costate-granular, complete; segment V, obsolete, granular, complete (Fig. 6E, F). Ventrosubmedian carinae, segments I–IV, obsolete, granular, complete; segment V, absent or obsolete, discontinuous granular row, restricted to anterior half. Ventromedian carina, segment V, obsolete, granular, complete, unmodified posteriorly. Dorsolateral, median lateral and, to a lesser extent, dorsomedian intercarinal surfaces, segments I–IV, finely and sparsely granular; segment V, smooth. Ventral intercarinal surfaces, segment I, smooth; segments II and III, finely and sparsely granular posteriorly; segments IV and V, more coarsely and densely granular, especially posteriorly. Metasomal segments uniformly sparsely setose. Telson vesicle acarinate, with compound subaculear tubercle, comprising at least three subspiniform granules ventrally and prominent anterodorsal lateral lobes; dorsal, lateral and ventral surfaces smooth; ventral surfaces moderately setose, becoming more so distally at base around subaculear tubercle.

Variation: The specimens from Ezelkopvlakte and Grootgraafwater on the Knersvlakte are markedly paler than those from Kamdaniekop and Loeriesfontein on the Bokkeveld plateau, lacking infuscation on the chelicerae and metasomal segment III, and most infuscation on the carapace and tergites including all or most of the pair of lateral stripes. The specimens from Langkloof in the Tankwa Karoo are more reddish in base colouration (Fig. 2E) than the specimens from the Bokkeveld plateau and the Knersvlakte, and more infuscate than the specimens from the Knersvlakte (Fig. 2D), but less so than the specimens from the Bokkeveld plateau, lacking most infuscation on the carapace and tergites including all or most of the pair of lateral stripes.

Holotype ♂ (AMNH): SOUTH AFRICA: Northern Cape Province: Calvinia District: Farm Loeriesfontein 675, 4.6 km N Loeriesfontein on road AP 2972 to Granaatboskolk, opposite landing strip, 30°54.348′S 19°25.449′E, 860 m, 16.ii.2007, L. Prendini & J. Huff, Nama/Succulent karoo transition on shallow pan with hard clayey-loam soil, cracked clay surface, with succulent mats, UV detection on cold, windy, moonless night, sympatric with Uroplectes carinatus (Pocock, 1890) and Opistophthalmus sp.

Paratypes: SOUTH AFRICA: Northern Cape Province: Calvinia District: same data as holotype, 6♂ 1♀ (AMNH), 1 subad. ♀ (AMCC [LP 6882]); Farm Ezelkopvlakte 333, 13.9 km SW intersection with R355 (Kliprand-Loeriesfontein) on Loop 6 road along Sishen-Saldanha railway line, 30°55.974′S 19°00.070′E, 369 m, 26.ii.2009, L. Prendini & H. Bichard, Succulent Karoo along pans in Kromrivier bed, mesems and Salsola L. dominant vegetation on consolidated, compacted alluvium, soft near surface but becoming harder below, UV detection on cool, still, dark night, specimens collected sitting on the ground, sympatric with Opistophthalmus spp., U. carinatus and U. gracilior Hewitt, 1914, 3♂ (AMNH); Kamdaniekop valley, 7 km SW Loeriesfontein, 30°59′S 19°24′E, 27–28.ii.1979, B.H. Lamoral, sympatric with U. carinatus, 15♂ 1♀ (NMSA 22128 old 11338). Sutherland District: Tankwa Karoo National Park: Farm Lange Kloof 60, Langkloof, 13 km NE intersection with P2250 (Calvinia-Ceres), 32°09.242′S 20°09.824′E, 662 m, 11.ii.2010, L. Prendini & I. Engelbrecht, dry riverbed (Langkloof) and adjacent steep rocky slopes, Succulent karoo on clayey-loam soil, relatively open area, UV detection on warm, moonless night with slight breeze, wind at 1 am, specimens sitting or walking on open, stony ground, sympatric with O. pallipes C.L. Koch, 1842, Parabuthus capensis (Ehrenberg, 1831) and Uroplectes sp., 3♂ (AMNH), 32°09.271′S 20°09.827′E, 655 m, ibid., 6♂ (AMNH), 1♂ (AMCC [LP 10382]). Western Cape Prov.: Vanrhynsdorp District: Farm Grootgraafwater, 31°18.06′S 18°29.34′E, 30.ix.2013, M. Weideman, active search, open ground, 2♂ (NCA 2014/257).

Distribution: Endemic to South Africa, and presently known from eight localities in the Calvinia and Sutherland districts of the Northern Cape Province, and the Vanrhynsdorp District of the Western Cape Province (Fig. 1). The type material originates from two localities situated very close to one another in Langkloof, on the western slope of the Roggeveldberge, in the Tankwa Karoo National Park, two localities in the Knersvlakte (Ezelkopvlakte and Grootgraafwater) and two on the Bokkeveld plateau (Kamdaniekop and Loeriesfontein). Glen Lyon (31°14.700′S 19°05.543′E), a third locality on the Bokkeveld plateau, is based only on a photographic record (Fig. 2C).

Ecology: The known locality records of U. ansiedippenaarae sp. n., which range in altitude from 370–860 m, occur in four vegetation zones of the Succulent Karoo Biome (Mucina et al. 2006): Central Knersvlakte Vygieveld, Northern Knersvlakte Vygieveld (Fig. 2A), Hantam Karoo (Fig. 2B), and Tanqua Escarpment Shrubland. All specimens were collected by UV light detection at night, except the specimen from Glen Lyon (Fig. 2C), which was captured in a pitfall trap. The specimens from Langkloof, a deep gorge on the western slope of the Roggeveldberge, were sitting or walking on open, stony ground on clayey-loam soil, near a dry riverbed and on the adjacent rocky slopes, on a warm, moonless night with a slight breeze. The specimens from Ezelkopvlakte were sitting on the ground on pans of consolidated, compacted alluvium in the dry bed of the Kromrivier, dominated by Mesembryanthemaceae Fenzl and Salsola bushes (Fig. 2A), on a cool, still, moonless night. The specimens from Loeriesfontein were sitting on a shallow pan of hard clayey-loam soil with a cracked surface, small stones, and Mesembryanthemaceae mats (Fig. 2B), on a cold, windy, moonless night. The habitat and habitus of U. ansiedippenaarae sp. n. are consistent with the lapidicolous ecomorphotype (Prendini 2001b). Eight other scorpion species were collected in sympatry at one or more of the localities: four buthids, Parabuthus capensis, U. carinatus, U. gracilior, and another species of Uroplectes, and five scorpionids, Opistophthalmus granifrons Pocock, 1896, O. pallipes and three other species of Opistophthalmus C.L. Koch, 1837.