Odontobuthus baluchicus, Barahoei & Prendini & Navidpour & Tahir & Aliabadian & Siahsarvie & Mirshamsi, 2022

Barahoei, Hossein, Prendini, Lorenzo, Navidpour, Shahrokh, Tahir, H. Muhammad, Aliabadian, Mansour, Siahsarvie, Roohollah & Mirshamsi, Omid, 2022, Integrative systematics of the tooth-tailed scorpions, Odontobuthus (Buthidae), with descriptions of three new species from the Iranian Plateau, Zoological Journal of the Linnean Society 195, pp. 355-398 : 365-369

ODONTOBUTHUS BALUCHICUS SP. NOV.

( FIGS 1–8 , TABLES 1 –5)

Zoobank registration: urn:lsid:zoobank.org:act:BA97ECB6-A884-4088-922A-FFAD47EA0C84

Odontobuthus doriae: Shahi et al., 2008: 211 (misidentification); Fekri et al., 2012: 137 (misidentification); Navidpour et al., 2013: 12 (misidentification).

Type material: Holotype ♀ ( SMF), three ♂♂, two ♀♀ paratypes ( ZMFUM), IRAN: Sistan and Baluchistan Province : Nikshahr , Chanf, Goank village, 26°38′N 60°27′E, 1199 m, 3.viii.2017, H. Barahoei, daytime excavation, sandy soil.

Etymology: The specific epithet is an adjective, derived from Baluchistan, the Iranian province where the type locality is located.

Diagnosis: Odontobuthus baluchicus may be separated from other species of the genus by the following combination of characters. Scorpions of medium to large size, adults 66–68 mm (♂) and 56–82 mm (♀) ( Fig. 6A–D ). Colour yellow to brownish-green. Median ocular tubercle situated in anterior half of carapace, distance from anterior carapace margin, 0.35– 0.39. Pedipalp chela movable finger long relative to manus (MFL/ML, 2.44–2.57). Median denticle rows of pedipalp chela fixed and movable fingers each comprising 13 or 14 oblique subrows of denticles. Pectinal tooth count, 29–31 (♂) and 20–24 (♀). Ventrosubmedian carinae of metasomal segments II and III each with two to four pairs of prominent tooth-like processes ( Fig. 7C, D, G, H ). Metasomal segment length to width (L/W), 1.83–2.11. Ventrolateral carinae of metasomal segment V with three or four prominent lobate processes; anal arch with two prominent lobes laterally; posteroventral margin of metasomal segment V with six reduced lobes. Telson small, narrow, length to width (TL/W), 2.22– 2.63 and length to height (TL/H), 2.42–2.63 ( Fig. 7A, B, E, F ).

KEY TO IDENTIFICATION OF THE SPECIES OF ODONTOBUTHUS

1. Metasomal segment V, anal arch with two lobes laterally.............................................................................. 2

- Metasomal segment V, anal arch with three lobes laterally........................................................................... 4

2. Metasomal segment II, ventrosubmedian carinae with three pairs of tooth-like processes ............ O. doriae

- Metasomal segment II, ventrosubmedian carinae with four or five pairs of tooth-like processes ............... 3

3. Adult length, 66–68 mm (♂), 56–82 mm (♀); metasomal segment I longer than wide .............. O. baluchicus

- Adult length, 43–55 mm (♂), 48–68 mm (♀); metasomal segment I equal to or wider than long.. O. kermanus

4. Colour greenish brown; metasomal segment III, ventrosubmedian carinae with four or five pairs of toothlike processes; segment V, anal arch with two large and one small lobes laterally......................... O. tirgari

- Colour light brown to yellow; metasomal segment III, ventrosubmedian carinae with two or three pairs of tooth-like processes; segment V, anal arch with three large lobes laterally .................................................. 5

5. Colour light brown; pedipalp chela movable finger, median denticle row comprising 13 or 14 subrows; metasomal segment I equal to or wider than long; segments II and III, ventrosubmedian carinae with two pairs of tooth-like processes.............................................................................................................................. 6

- Colour yellow; pedipalp chela movable finger, median denticle row comprising 10–12 subrows; metasomal segment I longer than wide; segments II and III, ventrosubmedian carinae with three or more pairs of tooth-like processes ........................................................................................................................................... 7

6. Metasomal segment V, anal arch with four reduced lobes posteroventrally.............................. O. bidentatus

- Metasomal segment V, anal arch with six reduced lobes posteroventrally.................................. O. tavighiae

7. Metasomal segment V, anal arch with six lobes posteroventrally; adult length <50 mm; occurs in India and Pakistan.......................................................................................................................................... O. odonturus

- Metasomal segment V, anal arch with two distinct lobes posteroventrally; adult length> 50 mm; does not occur in India or Pakistan................................................................................................................................. 8

8. Pedipalp chela movable finger short relative to chela manus (MFL/ML = 1.40–1.75); pectinal tooth count (♀), 20–25; occurs in the Arabian Peninsula ( Oman and United Arab Emirates................. O. brevidigitus

- Pedipalp chela movable finger long relative to chela manus (MFL/ML = 2.00–2.30); pectinal tooth count (♀), 18–20; occurs in Iran......................................................................................................... O. chabaharensis

Affinities: Odontobuthus baluchicus is closely related to O. doriae , with which it shares the presence of two prominent lateral lobes on the anal arch of metasomal segment V, and differs from all other species of the genus, which possess three lateral lobes. It differs from O. doriae in its coloration, longer than wide metasomal segment I and three pairs of prominent tooth-like processes on the ventrosubmedian carinae of metasomal segment II, and from O. kermanus in its larger body size and longer than wide metasomal segment I.

Description: Based on holotype ♀ (SMF) ( Figs 6A, B , 7A–D , 8A, C, E ) and paratype ♂ (ZMFUM 1302) ( Figs 6C, D , 7E–H , 8B, D, F ). Measurements: ♀: BL: 71.0; CL: 8.0; CWP: 9.3; CWA: 5.6; CX: 3.2; CY: 8.1; CHL: 15.4; ML: 4.3; MFL: 11.1; MtIL: 5.5; MtIH: 4.1; MtIW: 5.4; MtIIL: 6.0; MtIIH: 3.9; MtIIW: 4.7; MtIIIL: 6.2; MtIIIH: 3.8; MtIIIW: 4.2; MtIVL: 7.2; MtIVH: 3.6; MtIVW: 4.1; MtVL: 8.5; MtVH: 3.3; MtVW: 3.4; TL: 8.1; TW: 3.5; TH: 3.2. ♂: BL: 67.8; CL: 7.2; CWP: 7.6; CWA: 4.7; CX: 2.7; CY: 7.0; CHL: 14.7; ML: 4.2; MFL: 10.5; MtIL: 5.8; MtIH: 5.2; MtIW: 4.3; MtIIL: 6.5; MtIIH: 3.8; MtIIW: 4.6; MtIIIL: 6.7; MtIIIH: 3.5; MtIIIW: 4.0; MtIVL: 7.8; MtIVH: 3.2; MtIVW: 3.8; MtVL: 9.0; MtVH: 3.0; MtVW: 3.0; TL: 7.3; TW: 3.0; TH: 3.0. Colour: Carapace and mesosoma brownish-green, slightly paler ventrally; dark pigmentation around median and lateral ocelli. Pedipalps and legs lighter, distal part of femur and proximal part of patella darker especially on legs III and IV. Pectines light yellow to cream. Metasoma brown to yellow, segments darker dorsally, segment V darker than preceding segments. Telson vesicle yellowish-brown; aculeus brown anteriorly, becoming dark brown to black posteriorly. Chelicerae: Fi x e d f i n g e r ventral surface with two basal denticles. Movable finger prolateral and retrolateral distal denticles equal in size. Carapace: Trapezoid, wider than long, CWA/CL, 0.70 (♀) or 0.65 (♂), CWP/CL, 1.16 (♀) or 1.05 (♂); anterior margin moderately emarginate; median ocular tubercle situated in anterior half of carapace, CX/CL, 0.40 (♀) or 0.37 (♂), CX/CY, 0.39 (♀) or 0.38 (♂), distance between median ocelli twice ocular diameter; five pairs of lateral ocelli ( Fig. 6A, C ); anteromedian and posteromedian sulci deep (♂) or shallow (♀); posterolateral sulci w i d e, c u r v e d; c a r i n a e d i s t i n c t, c e n t r a l l a t e r a l and posteromedian carinae completely aligned; anteromedian carinae granular; central median, posteromedian and central lateral carinae granular (♀) or serratocrenulate (♂); intercarinal surfaces of prosoma finely granular. Pedipalps: Pedipalp segments relatively long. Femur 3.8 (♀) or 3.9 (♂) times longer than wide; four complete, granular carinae; retrodorsal, prodorsal and proventral carinae granular (♀) or serratocrenulate (♂); prolateral carinae comprising isolated spiniform granules; intercarinal surfaces smooth ( Fig. 8A, B ). Patella 2.96 (♀) or 3.5 (♂) times longer than wide; eight complete carinae; prodorsal carinae distinct, granular; dorsomedian, retrodorsal, retrolateral, retroventral and ventromedian carinae obsolete to moderate, smooth ( Fig. 8C ); proventral and prolateral carinae comprising several spiniform granules (♂) ( Fig. 8D ). Chela 3.6 (♀) or 3.5 (♂) times longer than manus; manus narrower (♀) or wider (♂) than patella; fingers 2.6 (♀) or 2.5 (♂) times longer than manus; median denticle subrows, including proximal subrow (left/right) of fixed finger, 13/13 and movable finger, 14/14; all subrows except proximal flanked by prolateral and retrolateral accessory denticles; movable finger with five (♂) or six (♀) subdistal denticles, two prolateral and three (♂) or four (♀) retrolateral. Orthobothriotaxic type A-β, with following segment totals: femur, 11 (five dorsal, four internal, two external) ( Fig. 8A, B ), patella, 13 (five dorsal, one internal, seven external) ( Fig. 8C, D ) and chela, 15 (eight manus, seven fixed finger) ( Fig. 8E, F ), totalling 39 trichobothria per pedipalp; trichobothria esb (fixed finger), Esb, Eb 3 (manus), d 2 (patella) and d 2 (femur) petite; trichobothrium et adjacent to proximal (♀) or distal (♂) end of median denticle subrow 7; est adjacent to midpoint (♀) or distal end (♂) of subrow 9 ( Fig. 8E, F ). Legs: Legs III and IV each with tibial spurs; I–IV each with bifurcate prolateral pedal spurs; telotarsi, ventral surfaces with two rows of fine setae. Sternum: Type I, triangular; slightly wider than long (♀) or longer than wide (♂); with deep median depression. Genital operculum: Completely divided longitudinally with fine, short bristles ( Fig. 6B, D ). Pectines: Distal margin extending to (♀) or beyond (♂) coxa-trochanter joint of leg IV; three marginal and eight (♀) or nine (♂) median lamellae; fulcra present; teeth present along entire posterior margin of pecten, count (left/right), 29/30 (♂) and 21/21 (♀). Mesosoma: Tergites I –VI tricarinate; VII pentacarinate, lateral carinae granular (♀) or serratocrenulate (♂), median carinae incomplete, restricted to anterior half of segment and weakly granular; intercarinal surfaces finely (♀) or coarsely (♂) granular. Sternites III–VI acarinate; VII with four moderate, granular carinae, lateral carinae restricted to anterior half of segment. Metasoma: Metasomal segment I decacarinate; II – IV octocarinate; V pentacarinate; all complete carinae moderately to markedly granular on segments I–III and weakly to moderately granular on IV (♀) or weakly to moderately granular on I–IV (♂). Lateral inframedian carinae incomplete, restricted to posterior half of segment II; vestigial, reduced to few granules posteriorly, on III. Ventrosubmedian carinae on segments II and III each with four pairs of rounded (♀) or subtriangular (♂) toothlike processes. Anteroventral margins of segment III with six large, rounded granules, IV with four (♂) to six (♀) large, rounded granules. Ventrolateral carinae on segment V markedly dentate with large, rounded (♀) or subtriangular (♂) lobate processes posteriorly; anal arch with two large (♀) or one small and two large (♂) lobes laterally and six distinct lobes posteroventrally ( Fig. 7A–H ). Telson: Oblong-ovoid, TH/TL, 0.39 (♀) or 0.41 (♂), TW/TL, 0.43 (♀) or 0.41 (♂); slightly wider than (TW/MtVW, 1.02) (♀) ( Fig. 7A, B ) or similar to (TW/MtVW, 1.00) (♂) ( Fig. 7E, F ) width of metasomal segment V; dorsal surface flat, ventral surface curved, smooth (♀) or sparsely granular (♂).

Distribution: Odontobuthus baluchicus is endemic to Iran and recorded in only two provinces: Hormozgan; Sistan and Baluchistan. The distributions of O. baluchicus , in south-eastern Iran, and O. kermanus , in central Iran, are allopatric.

Additional material: IRAN: Hormozgan Province: Jask–Beshagard road, 25°50′N 57°50′E, 149 m, 6.iv.2018, H. Barahoei, daytime excavation, four ♀♀ ( ZMFUM). Sistan and Baluchistan Province: Nikshahr, Konari village , 26°20′N 60°06′E, 660 m, 3.iv.2018, H. Barahoei, daytime excavation, sandy soil, two ♀♀, one subad. ♀ ( ZMFUM) .

Figures

Figure 1. Geographical distribution of the buthid scorpion genus Odontobuthus plotted on topography of the Middle East. A, known locality records obtained from fieldwork and the literature. Circles with black or white dots indicate type localites of each species. B, localities of material used in molecular phylogenetic analysis (see Table 1 for details).

Figure 2. Boxplots of sex-corrected total length for species of Odontobuthus occurring in Iran.

Figure 3. Lineardiscriminant analysis (LDA) of38 metricand fivemeristic variables among18 populationsofOdontobuthus. Conspecific populations in same colour.

Figure 4. Neighbour-joining phenogram generated from morphometric Mahalanobis distance matrix of 18 populations of Odontobuthus. Conspecific populations in same colour.

Figure 5. Fifty per cent majority rule consensus obtained by analysis of partial DNA sequences of mitochondrial COI gene from Odontobuthus with Bayesian inference (BI). Nodal support values above branches represent posterior probability values from BI and bootstrap values from maximum likelihood analyses, respectively. Letters A and B refer to clades also recovered by Azghadi et al. (2014).

Figure 6. Odontobuthus baluchicus. Habitus, dorsal aspect (A, C), ventral aspect (B, D). A, B, holotype ♀ (SMF). C, D, paratype ♂ (ZMFUM 1302). Scale bars = 10 mm.

Figure 7. Odontobuthus baluchicus. Metasomal segmentV and telson, lateral aspect (A, E), ventral aspect (B, F), metasomal segments II and III, lateral aspect (C, G), ventral aspect (D, H). A–D, holotype ♀ (SMF). E–H, paratype ♂ (ZMFUM 1302). Scale bars = 3 mm (A–D), 2.5 mm (E–H).

Figure 8. Odontobuthus baluchicus. Pedipalp femur, dorsal aspect (A, B), patella, dorsal aspect (C, D) and chela, lateral aspect (E, F). A, C, E, holotype ♀ (SMF). B, D, F, paratype ♂ (ZMFUM 1302). Scale bars = 2.5 mm.