Hottentotta pellucidus, Lowe, 2010

Lowe, Graeme, 2010, Two new species of Hottentotta Birula, 1908 (Scorpiones: Buthidae) from northern Oman, Euscorpius 103 (103), pp. 1-23 : 2-8

Hottentotta pellucidus , sp.nov.

Figs. 1–26 , 53–54 , 57–59 , 65–66 , Tab. 1

Holotype: adult ♂, Oman, Jabal Bani Jabir , UV detection on rocky terrain, rock strewn plateau with small wadis, on bare rock, 22°49.76' N 59°01.47' E, 1620 m a.s.l., 14 September 1995, 23:10 h, leg. G. Lowe, M.D. Gallagher & J. Dundon, NHMB.

Paratypes: Oman: 1 ♂, Jabal Bani Jabir , under stone, limestone plateau, 22°50' N 59°02' E, 1650 m a.s.l., 6 November 1992, leg. A.S. Gardner, SQU41, NHMB ; 2 ♂, Jabal Bani Jabir, UV detection, 22°49' N 59°02' E, 1800 m a.s.l., September 1995, leg. A. François & C. Delise, ONHM ; 9 ♂, 10 ♀, 7 juveniles, Jabal Bani Jabir, UV detection, stationary on rocks and ground under rocks, loose rock strewn plateau with small wadis, sparse vegetation, few bushes, grass, region of burial towers, 22°49.6' N 59°01.59' E, 1640 m a.s.l., 14 September 1995, 19:40 h, leg. G. Lowe, M.D. Gallagher & J. Dundon, NHMB , GL, ONHM; 15 ♂, 7 ♀, 10 juveniles, same locality as holotype, NHMB, MNHN, BMNH, FKCP ; 1 ♀, Ras Al Hamra , 23°38' N 58°30' E, May 1998, leg. C. Rose, NHMB ; 1 ♀, Jabal Bani Jabir, UV detection, rocky slope, 22°49.86' N 59°01.36' E, 1686 m a.s.l., 14 December 2001, 15:30–17:30 h, leg. A. Winkler, NHMB ; Jabal Bani Jabir , UV detection, rocky slope, between rocks, 22°49.6' N 59°01.36' E, 1695 m a.s.l., 12 December 2001, 18:30–21:30 h, leg. A. Winkler & B. Winkler, NHMB .

Diagnosis. Medium sized Hottentotta (Sissom, 1990; Kovařík, 2007; Sun, Zhu & Lourenço, 2010), adults 56– 70 mm; color uniform pale yellow without contrasting markings; carapace and tergites with strong, granular carinae; anterior margin of carapace with coarse granules; tergites tricarinate, posterior margins with carinae protruding in short spiniform processes; pedipalp femur, pedipalp patella, legs, metasoma and telson conspicuously hirsute, with numerous long and short macrosetae; metasoma with numerous intercarinal macrosetae; genital opercula densely setose; pedipalp chela finely hirsute with mostly short macrosetae; posterior margin of tergites I– VI mostly bare, usually with just one pair of short macrosetae internal to lateral carinae; pedipalps slender, femur L/ W 3.6 –4.4, patella L/ W 3.0 –3.5, chela L/ W 5.9 –6.5; pedipalp chela without carinae; pedipalp fixed finger primary denticles divided into 13–14 subrows (98 % of cases), movable finger primary denticles divided into 14–15 subrows (98 % of cases); male pedipalp fingers without strong basal scalloping; metasoma moderately robust, segment L/W ratios: metasoma I 1.01–1.15, metasoma II 1.24–1.40, metasoma III 1.29 – 1.48 , metasoma IV 1.50–1.85, metasoma V 2.02 – 2.40 ; metasoma I– III with 10 carinae, median lateral carinae complete but weak on segment III; lateral surfaces of metasoma I–IV coarsely granulated; pectine teeth in males 29–35, in females 25– 33 .

Etymology. The specific epithet refers to the uniform, pale yellow, semi-translucent body, which contrasts with the varied dark coloration of many other members of the genus.

Comparisons. Other species of Hottentotta with pedipalps bearing numerous long macrosetae are differentiated as follows: H. franzwerneri (Birula, 1914) , H. gentili (Pallary, 1924) , H. saulcyi (Simon, 1880) and H. schach (Birula, 1905) : larger scorpions (70–130 mm), dark color on carapace or body, tergites with numerous macrosetae, male with more swollen pedipalp chela manus; H. zagrosensis Kovařík, 1997 and H. lorestanus Navidpour et al., 2010 : larger scorpions (> 100 mm), body entirely black, tergites with numerous macrosetae; H. jabalpurensis Kovařík, 2007 : male with more swollen pedipalp chela manus, tergites with numerous macrosetae; H. scaber (Ehrenberg, 1828) : light and dark color pattern, metasoma with sparse setation, metasoma I–III more stout; H. flavidulus Teruel et Rein, 2010 : similar to H. pellucidus in being a smaller Hottentotta with uniform yellow coloration, but metasoma is more stout and lacks dense setation.

In Oman, the hirsute species H. jayakari (Pocock, 1895) and H. salei (Vachon, 1980) differ as follows: larger species (60–90 mm), dark pigmentation on body and pedipalps; denser pilosity on legs and pedipalps; numerous macrosetae on entire posterior margins of tergites I–VI; metasomal segments of adults more robust, with more sparse intercarinal setation ( H. salei ) or bare, lacking macrosetae ( H. jayakari ); lateral intercarinal surfaces of metasoma I–IV smooth, not granulated; male pedipalp chelae with more swollen manus and distinct scalloping at base of fingers.

Description (holotype male unless otherwise specified).

Coloration ( Figs. 1–4 ). Base color pale translucent yellow; without contrasting markings; melanic pigmentation confined to median and lateral eyes; denticles of chelicerae and pedipalp fingers, articular condyles of pedipalp movable fingers, tarsal ungues and aculeus of telson castaneous.

Carapace ( Figs. 1 , 5 ). Subquadrate, only slightly wider than long, dorsoventrally compressed, lateral flanks moderately sloped; median eyes slightly raised; lateral eyes with 5 ocelli (3 large, 2 small); anterior margin concave, smooth except for weak median denticulations, bordered by coarse granules; carination: anterior median, central median and posterior median carinae strongly developed, coarsely granular; central lateral and lateral ocular carinae less distinct, granular; central median and posterior median carinae not collinear, but connected by short transverse series of 4–6 granules; supraocular part of superciliary carinae smooth, postocular part with enlarged granule; other carinae indistinct; chaetotaxy: short macrosetae present on anterior part of carapace, 12 along anterior margin, 7 among anterior bordering granules, 1–2 behind lateral eyes, 2 on anterior median carinae; granulation: group of coarse granules on anterior interocular triangle behind lateral eyes; lateral flanks with coarse granulation; posterior median intercarinal area mostly smooth, with scattered fine granules; area between anterior median carinae smooth; posterior margin of carapace bordered by row of fine granules between posterior median carinae.

Chelicera (paratype male) ( Figs. 6–7 ). Dorsal surface of manus smooth, glabrous, with transverse row of coarse, subdistal granules; base of fixed finger with prominent dorsointernal carina bearing coarse granules; chaetotaxy: manus with pair of short pale microsetae on apical border; long reddish macroseta on dorsointernal carina, shorter reddish macroseta medially located on subdistal granule row; dorsal surface of movable finger with 5 short pale microsetae in distal half; manus ventrally smooth, bearing numerous long, fine microsetae, sparser medially, denser on medio-internal aspect, merging with dense setal brush on ventral aspect of fixed finger; dense fine setae extend to medial and dorsomedial surfaces at base of fixed finger; ventral surface of movable finger densely setose; dentition: fingers with normal buthid dentition (Vachon, 1963; Sissom, 1990); fixed finger with large distal tine, subdistal denticle and large proximal bicusp, two prominent denticles on ventral surface; movable finger with large dorsal and ventral distal tines; dorsal margin of movable finger with two large triangulate denticles and small proximal bicusp, ventral margin with two robust denticles.

Coxosternal area ( Fig. 2 ). Coxae smooth; posterior margins of coxae III–IV finely granulated proximally; coxa I with 8–9 macrosetae, endite I of coxa I with 9–12 macrosetae, endite II with 3–6 macrosetae; coxa II with 8–10 macrosetae on anterior and distal margins; coxa III with 5–6 macrosetae on anterior margin; coxa IV with single basal macroseta; sternum subtriangular, smooth anteriorly, finely granulated on posterior margin, with deep posteromedian excavation; genital opercula smooth, each with 20 short macrosetae; genital papillae present.

Pectines ( Figs. 2 , 19 ). Basal piece with deep anteromedian incision, surface smooth; 2 short macrosetae on left half; distal tips of pectines extending slightly past middle of trochanter IV; pectines with 3 marginal lamellae, 9 or 10 middle lamellae, plus small intermediate lamella at distal end of basal marginal lamella, 31–33 teeth; marginal lamellae, middle lamellae and fulcra with numerous short reddish macrosetae, 2–5 on fulcra; when anterior margins of both pectines are aligned with posterior margins of coxae IV, basal 3 teeth overlap with gap between basal middle lamellae.

Mesosoma ( Figs. 1–2 , 5 ). Tergites: pretergites smooth; tergites I–VI with 3 granulose, moderately strong carinae; median carinae of III–VI and lateral carinae of I–VI with terminal spinoid granule projecting slightly beyond posterior margins of tergites; lateral carinae of tergite I short, reduced to terminal projection; tergite VII with two pairs of coarsely granular lateral carinae, and granulated median hump; margins of all tergites with well-spaced small granules; lateral flanks of all tergites moderately sloped, with numerous coarse granules; median intercarinal surfaces mostly smooth, with sparse fine and coarse granules; tergites mostly bare with less than 4 macrosetae; tergites I–VI with paired marginal macrosetae on medial side of lateral carinae; additional small marginal macrosetae on lateral sides of lateral carinae on tergites III and VI; tergite VII devoid of macrosetae. Sternites: all sternites smooth, sternite III without carinae, sternites IV–VI with smooth, weak lateral carinae; sternite VII with 4 carinae, medial pair weak, smooth, lateral pair moderate, weakly granular; macrosetal counts on medial and lateral surfaces + posterior margin: III 29+15, IV 11+17, V 16+15, VI 19+7, VII 21+3; lateral margins shagreened on sternite III, denticulate on IV–VII, posterior margins microdenticulate on III–VI, granular on VIII.

Hemispermatophore (paratype male) ( Figs. 17–18 ). Flagelliform, trunk elongate, slender; flagellum filiform, relatively short, pars recta 0.2 times length of trunk, pars reflecta 0.4 times length of trunk; inner lobe a broad untapered lamina with truncate rounded apex; median lobe wide, triangulate with curved inner edge, outer lobe tapered, apically bent; basal lobe a stout blunt hook. Measurements (paratype): trunk L (to base of flagellum) 11.5 mm, pars recta 2.1 mm, pars reflecta 4.6 mm, inner lobe (from base of flagellum) 860 µm, median lobe 530 µm, outer lobe 400 µm, basal lobe 330 µm.

Metasoma ( Figs. 1–2 , 10–11 ). Moderately elongate, total length plus telson length 5.4 times carapace length; segments I–III with 10 carinae, segment IV with 8 carinae; segment V with 5 complete carinae; dorsosubmedian carinae strong, coarsely granular on I–VI; dorsolateral carinae strong, on I–IV, weak on V, coarsely granular on all segments; median lateral carinae strong, complete on segment I–II, weak, indistinct on anterior 1/4 of segment III, coarsely granulate on I–III; ventrolateral carinae strong, granulose on I–III, granulocrenulate on IV–V; ventrosubmedian carinae moderate, smooth on I–II, moderate to strong, granulose on III–IV; ventromedian carina strong, broadly granulated on V; ventrosubmedian carinae on V weak, nearly obsolete, only discernible on anterior 1/3 of segment, marked by linear series of coarse dentate granules; dorsal intercarinal surfaces smooth on segments I–IV, smooth medially and weakly granular laterally on V; dorsolateral intercarinal surfaces weakly granular on I, strongly, coarsely granular on II–IV; segment I granulated on lateral surface above median lateral carina, ventrolateral and ventral intercarinal surfaces smooth; segments II–V with coarse granulation on lateral and ventral intercarinal surfaces; lateral anal lobes not dissected; ventral anal arc with 26 crenulations; chaetotaxy: ventrolateral and ventral surfaces on all segments with numerous long macrosetae on carinae and intercarinal surfaces; dorsolateral intercarinal surfaces with macrosetae absent on I– III, present on IV; dorsosubmedian carinae with macrosetae absent on I, present on II–IV; dorsal intercarinal surfaces of all segments lacking macrosetae; segment V with macrosetae around dorsolateral carinae.

Telson ( Figs. 10–11 ). Vesicle bulbous, steeply sloped posteriorly; dorsal surface of vesicle smooth, without setae, lateral and ventral surfaces studded with coarse granules, bearing numerous long macrosetae; aculeus robust, curved, slightly shorter than vesicle.

Pedipalp ( Figs. 12–16 , 21–26 , 53–54 ). Femur ( Fig. 12 ): slender, 4.03 times longer than wide; dorsoexternal, dorsointernal and ventrointernal carinae moderate, with regular small dentate granules; other carinae obsolete; dorsal surface flat, external surface convex, ventral surface concave, all smooth; internal surface convex, with scattered enlarged dentate granules; distal external macrosetae arranged in two longitudinal rows on distal half of femur (16–20 shorter ventral setae, 9–11 longer dorsal setae); numerous long and short macrosetae on dorsoexternal, dorsointernal and ventrointernal carinae, and dorsal and internal surfaces; ventral surface without setae. Patella ( Figs. 13–14 ): elongate, 3.14 times longer than wide; dorsointernal carina moderate, weakly granulose; dorsomedian and ventromedian carinae weak, smooth to weakly granular; internal carina weak, marked by widely spaced granules; other carinae obsolete; all intercarinal surfaces smooth; external, dorsal and internal surfaces with numerous long and short macrosetae, ventral surface without setae. Chela ( Figs. 15–16 , 53–54 ): slender with tenuous fingers, 6.12 times longer than wide; movable finger 2.45 times manus ventral length; manus smooth, carinae obsolete; fixed and movable fingers smooth, lacking scalloping of proximal dentate margins; short macrosetae dense on dorsal, external and ventral surfaces of manus and fingers, sparse or absent on internal surfaces; 14 primary denticle subrows on both fixed and movable fingers ( Figs. 53– 54 ); all denticle subrows flanked by internal and external accessory denticles, except for most proximal subrow of fixed finger; movable finger with 4 enlarged subdistal denticles. Trichobothrial pattern ( Figs. 21–26 ): orthobothriotaxic, type Aβ (Vachon, 1974; 1975); femur d 2, patella d 2, chela Eb 3, Esb and esb petite; patella with d 3 internal to dorsomedian carina (Fet, Soleglad & Lowe, 2005); db positioned on fixed finger midway between est and et (Kovařík, 2007); line joining V 1 and V 2 on manus oblique, not perpendicular to axis of movable finger articulation (Sun, Zhu & Lourenço, 2010).

Legs ( Figs. 1–2 , 8–9 ). Slender; ventral carinae prominently denticulate on femora, weakly crenulate on tibiae; legs III–IV with tibial spurs; retrolateral pedal spurs simple, non-setose; prolateral pedal spurs basally bifurcate, bearing 0 (I) or 1 (II–IV) macrosetae; prolateral and retrolateral surfaces of basitarsi and telotarsi with numerous macrosetae, not arranged into wide bristle-combs; ventral aspect of basitarsi I–III with single row of short, stout macrosetae; ventral aspect of telotarsi I–IV paired rows of stout spiniform macrosetae; ungues stout.

Measurements of holotype male (mm). Total L 60.00; metasoma and telson L 37.50; carapace L 6.97, anterior W 3.57, posterior W 7.37, preocular L 2.79; metasomal segments (L/D/W) I 4.68/3.51/4.37, II 5.42/3.43/4.30, III 5.89/3.52/4.23, IV 6.84/3.61/4.05, V 8.00/3.41/3.72; telson L 7.47; vesicle L 4.44, D 3.12, W 3.11; pedipalp chela L 14.38, manus ventral L 4.26, chela W 2.35, D 2.42, fixed finger L 9.05, movable finger L 10.42; pedipalp femur L 7.62, W 1.89, patella L 8.03, W 2.56; pectine L 8.44; leg III patella L 6.33, D 1.58, sternite VII L 4.43, W 7.27.

Adult female (paratype, Jabal Bani Jabir) ( Figs. 3–4 , 20 , 5 9 ). Similar to male, but differs as follows: a larger scorpion, coarser granules on carapace and tergites; pectines shorter, distal tips extending to proximal 1/4 of trochanter IV, with 7–8 middle lamellae; pectine teeth smaller, shorter; when anterior margins of both pectines are aligned with posterior margins of coxae IV, basal teeth do not overlap; basal piece with more shallow anteromedian incision; lateral carinae obsolete on sternite IV.

Measurements of paratype female (mm). Total L 6 4.00; metasoma and telson L 36.50; carapace L 7.40, anterior W 3.52, posterior W 7.66, preocular L 2.91; metasomal segments (L/D/W) I 4.48/3.58/4.51, II 5.22/3.55/4.33, III 5.54/3.58/4.16, IV 6.51/3.56/3.96, V 8.00/3.39/3.73; telson L 7.37; vesicle L 4.50, D 2.91, W 3.12; pedipalp chela L 14.16, manus ventral L 4.00, chela W 2.43, D 2.43, fixed finger L 9.05, movable finger L 10.18; pedipalp femur L 6.90, W 1.77, patella L 8.22, W 2.69; pectine L 7.31; leg III patella L 6.19, D 1.65; sternite VII L 4.12, W 7.48.

Variation. Juveniles: differed from adults as follows: carapace and tergites with weaker carination, intercarinal surfaces smooth; metasoma I–IV with weaker, finely granulated carinae, intercarinal surfaces smooth; metasoma V smooth except for granules on ventral surface; metasomal setation more sparse, most setae located on carinae; setation on pedipalps, basitarsi and telotarsi more sparse; metasoma V with faint fuscous markings on lateral and ventral surfaces.

Sexual dimorphism: Morphometric data for adults of both sexes are summarized in Table 1. Males had on average significantly longer (relative to carapace) and more slender metasomal segments, pedipalps, legs, pectines and sternite VII than females. Pectine teeth: males 29–35 (mode 33, 62/68 = 91.2% of combs with 31–34 teeth), females 25–33 (mode 29, 60/78 = 76.9% of combs with 27–30 teeth). The number of denticle subrows on the pedipalp fingers of males was not significantly different from that of females. The mean number of subrows for movable fingers was significantly higher than that for fixed fingers (P <0.001, paired t-test, n = 142). In 143 fixed fingers (sexes pooled), there were 39/143 (27.3 %) with 13 subrows, 101/143 (70.6 %) with 14 subrows, and 3/143 (2.1 %) with 10 or 12 subrows; in 143 movable fingers (sexes pooled), there were 107/143 (74.8 %) with 14 subrows, 33/143 (23.1 %) with 15 subrows, and 3/143 (2.1 %) with 6 or 13 subrows.

Reproduction. An adult female from Jabal Bani Jabir, collected on 14 September 1995, was held in isolated captivity, and on 21 August 1998 was observed after parturition with a live second instar juvenile and 4 dead embryos. This suggests that this species is capable of storing viable spermatozoa for up to 3 years (Kovoor, Lourenço & Muñoz-Cuevas, 1987). The abundance of males implies that this is not a parthenogenetic population (Matthiesen, 1962; Lourenço, 2002).

Distribution ( Figs. 65–66 ). This species is found on Jabal Bani Jabir in the eastern Al Hajar Mountains (Al Hajar Ash Sharqi) of Oman, where all specimens were collected at high elevation (> 1,600 m a.s.l.). A single isolated specimen from Ras al Hamra, along the edge of the sea near Muscat, may be a spurious record due to human transport. There were no other specimens of this species in a large sample of scorpions (2,048) collected from lower elevations (<1,500 m a.s.l.), including the heavily populated coastal areas in the vicinity of Muscat. The lack of records from the western Al Hajar ranges suggests that this species does not cross the Sumail Gap dividing the eastern and western ranges, and may be confined to higher elevations in the eastern Al Hajar.

Ecology. Ultraviolet detection on Jabal Bani Jabir revealed a dense population of H. pellucidus on the remote high plateau of Shir (1,600 –1,800 m a.s.l.). At the collection sites the terrain was open, very dry, sparsely vegetated and littered with abundant loose rock broken into blocks and slabs ( Figs. 61–63 ). The scorpions were found at night sitting stationary, some clinging to rocks, others on the ground under the edges of loose rocks. Many males were wandering out in the open. Other less common lithophilic or lapidicolous scorpions collected in the same area included Compsobuthus maindroni (Kraepelin, 1900) , Hemiscorpius flagelliraptor Lowe, 2010 , Nebo omanensis Francke, 1980 and Microbuthus gardneri Lowe, 2010 . The Shir Plateau is an important archaeological site where prehistoric residents of the 3 rd millennium BC utilized the same broken rock that provides so much scorpion microhabitat to construct tower tombs that still stand as memorials to respected members of their society ( Fig. 63 ) (Yule & Weisgerber, 1998; Seibert et al., 2005).

Figures

Figures 1–4: H. pellucidus, sp. nov., habitus, 1–2, holotype male; 3–4, paratype female. 1, 3. Dorsal aspect. 2, 4. Ventral aspect. Scale bar: 10 mm.

Figures 5–11: H. pellucidus, sp. nov. 5, 8–11, holotype male; 6–7, paratype male (Jabal Bani Jabir). 5. Carapace and tergites I– II, dorsal aspect. 6–7, right chelicera. 6. Dorsal aspect. 7. Ventral aspect. 8–9, right basitarsus and telotarsus III. 8. Ventral aspect. 9. Retrolateral aspect. 10–11, metasoma and telson. 10. Right lateral aspect. 11. Ventral aspect. Scale bar: 5: 3.19 mm; 6–7: 2.125 mm; 8–9: 1.5 mm; 10–11: 6.22 mm.

Figures 12–20: H. pellucidus, sp.nov., 12–16, 19, holotype male; 17–18, paratype male; 20, paratype female. 12. Right pedipalp femur, dorsal aspect. 13. Right pedipalp patella, dorsal aspect. 14. Right pedipalp patella, external aspect. 15. Right pedipalp chela, external aspect. 16. Right pedipalp chela, ventral aspect. 17–18. Right hemispermatophore, lobes at base of flagellum. 17. Convex aspect. 18. Inner aspect. 19. Left male pectine, ventral aspect. 20. Left female pectine ventral aspect. Scale bar: 12–16, 19–20: 4.1 mm; 17–18: 1.06 mm.

Figures 21–26: H. pellucidus, sp. nov., trichobothrial map, holotype male. 21. Right pedipalp femur, dorsal aspect. 22. Right pedipalp femur, proximal internal aspect. 23. Right pedipalp patella, dorsal aspect. 24. Right pedipalp patella, external aspect. 25. Right pedipalp chela, external aspect. 26. Right pedipalp chela, ventral aspect. Trichobothrial notation after Vachon (1974).

Figures 53–56: Pedipalp finger dentition of new Hottentotta species. 53–54, H. pellucidus, sp. nov., holotype male. 55–56, H. saxinatans, sp. nov., holotype male. 53, 55: right fixed finger, ventral aspect. 54, 56: right movable finger, dorsal aspect. Scale bar: 1 mm. Images acquired under UV fluorescence.

Figures 57–64: In vivo habitus and habitats of new Hottentotta species in Oman. 57–59. H. pellucidus, sp. nov. 57–58. Paratype male. 59. Paratype female. 60. H. saxinatans, sp. nov., paratype female. 61–63. Shir Plateau, Jabal Bani Jabir, type locality of H. pellucidus. 61–62. Terrain photos showing extensive fields of loose rock. 63. Prehistoric tower tomb constructed from broken rock.64. Jabal Shams, type locality of H. saxinatans.

Figures 65–66: Maps showing collection sites of new species of Hottentotta in northern Oman. 65. Records plotted on larger scale terrain and elevation map of southeast Arabia with geopolitical borders. 66. Records plotted on color topographic map of northern Oman showing locations in the Al Hajar mountain ranges. Magenta circles: H. pellucidus, sp. nov.; red circles: H. saxinatans, sp. nov. The isolated record of H. pellucidus at Muscat may be spurious.