Leiurus nigellus, Afifeh & Aloufi & Al-Saraireh & Badry & Al-Qahtni & Amr, 2023

Afifeh, Bassam Abu, Aloufi, Abdulhadi, Al-Saraireh, Mohammad, Badry, Ahmed, Al-Qahtni, Abdulmani H. & Amr, Zuhair S., 2023, A new remarkable species of Leiurus Ehrenberg, 1828 from Saudi Arabia (Scorpiones: Buthidae), Ecologica Montenegrina 69, pp. 91-106 : 93-101

Leiurus nigellus sp. nov. Abu Afifeh, Aloufi & Al-Saraireh

https://zoobank.org/ urn:lsid:zoobank.org:act:F2C4226B-233D-4266-BF78-8FD6C8C5195B ( Figures 1-7 ; Tables 1 and 3)

Type material examined: Saudi Arabia: holotype: 1 ♀, BAPC 0250 , Al Buriakah, beside old Tabuk-Al Ula highway, Al Ula Governorate , Al Madinah Al Monawwarah Province , 27° 19' 53.99"N, 37° 47' 31.11"E, 1109 m a.s.l., 5 August 2023, leg. A. Aloufi. Paratypes: 1 ♀, BAPC 0251 , 1 juv. ♀, BAPC 0254 , Al Buriakah, beside old Tabuk-Al Ula highway, Al Ula Governorate , Al Madinah Al Monawwarah Province , 27° 19' 53.99"N, 37° 47' 31.11"E, 1109 m a.s.l., 29 July 2023, leg. A. Aloufi. 2 ♀♀, BAPC 0252-0253 , 1 subadult ♀, BAPC 0255 , 3 ♂♂, BAPC 0256-0258 , 1 subadult ♂, BAPC 0259 , Al Buriakah, beside old Tabuk-Al Ula highway, Al Ula Governorate , Al Madinah Al Monawwarah Province , 27° 19' 53.99"N, 37° 47' 31.11"E, 1109 m a.s.l., 5 August 2023, leg. A. Aloufi.

Comparative material examined:

Saudi Arabia: Leiurus arabicus : 1 ♂, BAPC 0150 , 1 ♀, BAPC 0151 , Alaab, Al Madinah Al Monawwarah Province , 24° 06' 13.08"N, 38° 55' 48.13"E, 412 m a.s.l., 21 March 2019, leg. A. Aloufi. 1 ♀, BAPC 0149 , Wadi Al Jala'b, Al Madinah Al Monawwarah Province , 24° 44' 25.80"N, 39° 42' 57.29"E, 838 m a.s.l., 6 August 2017, leg. A. Aloufi. Leiurus haenggii : 1 ♂, BAPC 0200 , 1 ♀, BAPC 02011 , Wadi Reem (Al Aseel), Al Madinah Al Monawwarah Province , 23° 55 '06.50"N, 39° 18' 05.50"E, 1090 m a.s.l., 23 May 2022, leg. A. Aloufi. 1 ♀, BAPC 02021 , Al Fegrah (Wadi Mzaber), Al Madinah Al Monawwarah Province , 24° 21' 44.34"N, 38° 57' 44.75"E, 1551 m a.s.l., 28 August 2022, leg. A. Aloufi. Jordan: Leiurus jordanensis : 1 ♂, 2♀♀, BAPC 0100-0102 , Al Mudawwarah, Ma'an Governorate, 29° 23' 05.7" N 35°54' 10.2" E, 24 October 2020, leg. B. Abu Afifeh & M. Al-Saraireh. 4♀♀, BAPC 0102-0105 , Wadi Rum , 13 km SE Al Ghal, Aqaba Governorate, 29° 26' 00.1" N, 35° 40' 56.8" E, 890 m a.s.l., 15 July 2022, leg. B. Abu Afifeh & R. Abu Afifeh . 6 ♀♀, BAPC 0106-0111 , Batn El-Ghol , Ma'an Governorate, 29° 42' 48.4" N, 36° 08' 53.6" E, 879 m a.s.l., 7 July 2023, leg. B. Abu Afifeh & R. Abu Afifeh. Leiurus hebraeus : 2♀♀, BAPC 0300-0301 , Wadi Shueib , Balqa Governorate, 31° 56' 10.0" N 35°39' 55.0" E, - 5 m a.s.l. 20 July 2023, leg. B. Abu Afifeh & M. Al-Saraireh.

Etymology: The specific epithet from Latin “ nigellus ” is masculine adjective, diminutive of “ niger ” (Black), which refers to the predominantly blackish colour of the new species.

Diagnosis: Large Leiurus , adults 81-104 mm in total length, carapace of female reaching 11.40 mm in length; body colour is predominantly black; carapace, mesosoma, metasoma and telson, pedipalps and proximal segments of legs black to blackish-brown; distal third of pedipalp chela fingers and the three most distal segments of legs dark yellow to yellowish-brown; anterior margin of carapace slightly concave; all carapace carinae strongly developed; central lateral and posterior median carinae fused to form lyre shaped row of granules. chelicerae with characteristic buthid dentition (Vachon, 1963); tergites I–II, VII pentacarinate, III–VI tricarinate; sternites III with weak to moderate median carinae in females; strong in males; pectinal tooth counts ranging from 36-39 in males and 29-33 in females. Pedipalps slender; femur L/W 4.25 in male, 3.80-3.96 in females; patella L/W 4.00 in male, 3.35-3.60 in females; chela L/W 7.96 in male, 7.00- 7.60 in females; fixed and movable finger of pedipalps with 12-13 rows of granules and marked accessory granules; trichobothrial pattern orthobothriotaxic, type A-β ( Vachon, 1974, 1975); pedipalp chela fixed finger with trichobothrium db distal to est; metasoma I–III with 10 carinae, median lateral carinae complete on I, reduced on II–III; metasoma IV with 8 carinae; metasoma V with 7 carinae; metasoma slender, metasoma I L/W 1.36 in male, 1.27-1.30 in females, metasoma II L/W 1.91 in male, 1.78-1.86 in females; metasoma III L/W 2.16 in male, 1.97-2.10 in females; metasoma IV L/W 2.81 in male, 2.52-2.62 in females; metasoma V L/W 3.40 in male, 2.97-3.11 in females. F s (slenderness factor) of adult females ranging from 27.78–32.32.

Description: Based on female holotype and paratypes. Measurements are in Table (1).

Coloration. Generally black ( Figs. 1 & 2 ), carapace black to blackish-brown; tergites black to blackish-brown; venter yellowish-brown except sternite VII blackish-brown; metasomal segments black to blackish-brown; vesicle black to blackish-brown; aculeus dark reddish-brown at the base and dark black at its extremity; chelicerae retrodorsal surface dark yellow to yellowish-brown; prodorsal surface reticulated with dense dark spots; teeth blackish; pedipalps black to blackish-brown overall excepted for the chela fingers which are gradually turn to yellowish-brown on the distal third; rows of granules on the dentate margins of the fingers dark red; legs with black to blackish-brown proximal segments and the three most distal becoming lighter.

Morphology

Prosoma ( Figs. 3 & 4 ). Anterior margin of carapace slightly concave; all carapace carinae strongly developed, granulose, including central median, posterior median, anterior median, central lateral and central median; central lateral and posterior median carinae fused to form lyre shaped row of granules. Intercarinal spaces with very few irregular granules and almost smooth laterally and distally; median ocular tubercle only slightly anterior to the centre of the carapace, almost in a central position; median eyes separated by slightly more than two ocular diameters; five pairs of lateral eyes; (3 large, 2 small) on each side.

Mesosoma ( Figs. 3 & 4 ). Tergites I, II and VII pentacarinate; III and IV tricarinate; all carinae strong, granular; median carina on I moderate to strong; on II-VI strong, crenulate; terminating distally on each segment with a spinoid process that extends very slightly beyond the posterior margin of the tergite; tergite VII with 5 strong, granular carinae; inner and outer lateral carinae joined anteriorly by transverse granule rows; median carina present on anterior one-half to 2/3 of the total length, moderate to strong. Intercarinal spaces weakly granular, almost smooth, excepted for the lateral margins of tergites III-VI which are strongly granulated; sternites: lateral carinae absent from sternite III; moderate to strong on sternites IV-VI; strong, crenulate on VII; median carinae on sternite III weak to moderate, irregularly granular; on IV weak; on V weak to obsolete; on VI moderate; on VII strong crenulate. Pectines long; reaching to or slightly beyond coxa-trochanter joint of leg IV in the female, well beyond this articulation in males; pectinal tooth count 36- 39 in males and 29-33 in females. Pectines with 3 marginal lamellae, 9 middle lamellae, marginal and middle lamellae with dense cover of short reddish macrosetae; fulcra with 4–7 setae.

Metasoma ( Fig. 5 ). Metasomal segments I to III with 10 carinae, crenulate; median lateral carinae on I moderate to strong, crenulate; on II present on posterior one-third, crenulate; on III limited to posterior onefifth; IV with 8 carinae; dorsosubmedian carinae moderate on I–II, weak on III–IV; dorsolateral and ventrolateral carinae moderate on I–IV; ventromedian carinae moderate on segments I to IV. Segment V with 7 carinae; dorsolateral carinae very weak, faintly granulated, ventrolateral carinae strong with dentate granules increasing in size posteriorly, with several slightly enlarged subtriangular denticles, ventrosubmedian carinae marked by series of small to medium dentate granules on anterior 2/3 of segment, ventromedian carina strong, armed with small to large more spiniod than lobate granules; anal arch with 3 lateral spinoid lobes and 12-13 irregular, transverse crenulations on ventral margin. Dorsal furrows of all segments moderately to weakly developed with a thin granulation, almost smooth; intercarinal surfaces smooth on segment I, smooth to minutely shagreened on II-III, sparsely, finely shagreened on IV-V.

Telson ( Fig. 5 ). Vesicle smooth, bulbous; ventral surface with scattered fine microsetae and several short macrosetae; aculeus slightly shorter than vesicle, subaculear tubercle absent.

Chelicerae: Dorsal surface of manus smooth, convex, prodorsal margin finely granular; retrodorsal surfaces smooth; prolateral and ventral surfaces densely setose; fingers with normal buthid dentition (Vachon, 1963), fixed finger dorsal and ventral surfaces densely setose, dorsal margin bears 4 teeth: distal, subdistal, median, and basal; ventral margin with basal and median denticles; movable finger dorsal surface smooth; ventral surface densely setose; dorsal margin bears 5 teeth: distal, subdistal, median, and a pair of basal denticles fused in bicusp; ventral margin with distal, median, and basal teeth. The movable finger always ends in two distal teeth–one dorsal and one ventral– between which is inserted the distal tooth of the fixed finger.

Pedipalps

Femur ( Figs. 6 A-B, G-H) slender, L/W= 3.8; with five carinae; dorsoexternal, dorsointernal and ventrointernal carinae strong with regular large conical granules; internal carina strong, with irregular large granules; external carina obsolete, a smooth ridge with isolated large dentate granules; dorsal and internal surfaces finely, sparsely shagreened, ventral and external surfaces nearly smooth.

Patella ( Figs. 6 C-D, I-J) slender, L/W= 3.8; with seven carinae; dorsointernal carinae moderate to strong, with one conspicuous spinoid granule and several smaller granules; dorsomedian carina weak, finely granular; dorsoexternal, external and ventroexternal carinae weak, smooth; ventromedian carina weak, with fine granules; ventrointernal carina weak, with well-spaced medium to small granules and ventral patellar spur; internal carina moderate, with closely spaced small granules and dorsal patellar spur.

Chela ( Figs. 6 E-F, K-L). slender, L/W=7.44; with elongated fingers; all carinae almost vestigial. Dentate margins of fixed and movable fingers composed of 12-13 almost linear rows of granules and conspicuous accessory granules ( Figs. 7 , C-D, G-H).

Trichobothrial pattern orthobothriotaxic ( Fig. 6 ). type A ( Vachon, 1974); dorsal trichobothria of femur in beta configuration ( Vachon, 1975); pedipalp chela fixed finger with trichobothrium db distal to est.

Legs: ( Figs. 7 , A-B, E-F). with ventral aspect of tarsi presenting numerous thin setae not well arranged in rows. retrosuperior setae on basitarsus III counts 12-15. Tibial spurs present on legs III and IV strong. Pedal spurs present, strong on all legs, prolateral spurs basally bifurcate.

Sexual dimorphism:

Males differed from females as follows: Males with more robust carination on tergites and sternites III–V, more slender pedipalps and metasoma, longer pectines with larger teeth.

Affinities

Leiurus nigellus sp. nov. is distinguished from most other species of Leiurus known from the Arabian Peninsula by its distinctive predominantly blackish colour pattern, the new species differs from L. jordanensis by having: (a). less slender body parts, including metasomal segments, legs and pedipalps ( Table 3); and by combining morphometric ratios describing slenderness of three segments (leg, pedipalp and metasomal segments) of adult females resulted in F s that ranged from 27.78–32.32 (n=4) in L. nigellus sp. nov., 35.06–41.78 (n =12) in L. jordanensis ; (b). sternite III with median carinae weak to moderate, irregularly granular, sternites IV–V with lateral carinae moderate, granular, median carinae weak in females of the new species, whereas sternite III with median carinae strong, granular, sternites IV–V with lateral carinae strong, granular, median carinae moderate in females L. jordanensis ; (c). different colour pattern, with vesicle of telson black to blackish brown in adults, and it is light black in juveniles, whereas the vesicle is yellow in adults and juveniles of L. jordanensis , also pedipalp fingers of the new species are black to blackish brown overall except for the distal third with yellowish-brown, but they are completely yellow in L. jordanensis .

Leiurus arabicus is distinguished from L. nigellus sp. nov. by having: (a). less slender metasomal segments, and less slenderness factor in adult females (Table 2 & 3); Fs ranged from 26.24–26.27 in females (n=2); (b). different colour pattern, base colour is yellow, with less or more dark reddish-brown pigmentation on carapace, tergites and metasoma V, in contrast the new species is black to blackish-brown overall; (c). ventrolateral carinae of metasoma V with enlarged triangular or subtriangular denticles, whereas in L. nigellus sp. nov. ventrolateral carinae of metasoma V with slightly enlarged subtriangular denticles.

Leiurus haenggii is distinguished from L. nigellus sp. nov. by having (a). less slender metasomal segments, legs and pedipalps (Table 2 & 3); Fs ranged from 20.02–21.23 in females (n=2); (b). sternite III with median carinae very weak, smooth, almost obsolete; sternites IV–V with weak, finely granulated lateral carinae, obsolete median carinae; whereas sternite III with median carinae weak to moderate, irregularly granular, sternites IV–V with lateral carinae moderate, granular, median carinae weak in females of the new species; (c). different colour pattern, base colour is yellow, with less or more dark reddish-brown pigmentation on carapace, tergites and metasoma V, in contrast L. nigellus sp. nov. is black to blackish-brown overall; (d). ventrolateral carinae of metasoma V with enlarged subtriangular or lobate denticles, whereas in L. nigellus sp. nov. ventrolateral carinae of metasoma V with slightly enlarged subtriangular denticles.

Habitat

The collection site is located in Al Buriakah village (1109 m a.s.l.), 130 km north of Al Ula Governorate, north of Al Madinah Al Monawwarah Province. Leiurus nigellus sp. nov. was collected from an arid environment with sparse vegetation. The habitat is a flat desert covered with thin layer of sand on top of gravel with scattered sandstone bed rocks of various sizes, with several deserted rodent burrows ( Fig. 8 ). More to the west, sandstone deserts become more prominent interrupted by narrow wadi systems, with few vegetation of Haloxylon salicornicum , Retama raetam , Panicum sp. and Citrullus colocynthis . Other scorpions found in the same area include Androctonus crassicauda (Olivier, 1807) , Vachoniolus globimanus Levy, Amitai & Shulov, 1973 , and Buthacus sp.

Figures

Figure 1. Leiurus nigellus sp. nov., female paratype from Al Buriakah, Al Ula governorate, Saudi Arabia.

Figure 2. Habitus of Leiurus nigellus sp. nov., male paratype and female holotype. A. male in dorsal view. B. male in ventral view. C. female in dorsal view. D. female in ventral view. Scale bar = 20 mm.

Figure 3. Leiurus nigellus sp. nov., female holotype under UV light. A. carapace and mesosoma. B. sternopectinal area and ventral of mesosoma. Scale bar = 5 mm.

Figure 4. Leiurus nigellus sp. nov., male paratype under UV light. A. carapace and mesosoma. B. sternopectinal area and ventral of mesosoma. Scale bar = 5 mm.

Figure 5. Leiurus nigellus sp. nov. female holotype under UV light. A. metasoma and telson dorsal view. B. metasoma and telson ventral view. C. metasoma and telson lateral view. Male paratype under UV light. D. metasoma and telson dorsal view. E. metasoma and telson ventral view. F. metasoma and telson lateral view. Scale bar = 5 mm.

Figure 6. Leiurus nigellus sp. nov., pedipalp segments, female holotype (A-F), A. femur internal view. B. femur dorsal view. C. patella dorsal view. D. patella external view. E. chela external view. F. chela ventral view; male paratype (G- L), G. femur internal view. H. femur dorsal view. I. patella dorsal view. J. patella external view. K. chela external view. L. chela ventral view. Trichobothrial pattern indicated by yellow circles. Scale = 5 mm.

Figure 7. Leiurus nigellus sp. nov., right tibia, basitarsus, and telotarsus, retrolateral view, female holotype, A. leg III. B. leg IV. C. pedipalp chela fixed finger. D. pedipalp chela movable finger; male paratype. E. leg III. F. leg IV. G. pedipalp chela fixed finger. H. pedipalp chela movable finger.

Figure 8. Habitat of Leiurus nigellus sp. nov. in Al Buriakah village, Al Ula Governorate, Al Madinah Al Monawwarah Province, Saudi Arabia.