Odontobuthus chabaharensis, 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 : 372-377

ODONTOBUTHUS CHABAHARENSIS SP. NOV.

( FIGS 1–5 , 9–11 , TABLES 1 –5)

Zoobank registration: urn:lsid:zoobank.org:act:9D7EDE35-D7A4-4212-98C1-62875DE1B881

Type material: Holotype ♀ ( SMF), one ♂, two ♀♀ paratypes ( ZMFUM), IRAN: Sistan and Baluchistan Province : Chabahar, Parak-e Sheykhan village, 25°30′N 60°35′E, 19 m, 13.vi.2019, H. Barahoei, daytime excavation, silty clay.

Etymology: The specific epithet is an adjective derived from Chabahar, the type locality.

Diagnosis: Odontobuthus chabaharensis may be separated from other species of the genus by the following combination of characters. Scorpions of small to medium size, adults 36 mm (♂) and 53–63 mm (♀) ( Fig. 9A–D ). Colour golden yellow. Median ocular tubercle situated in anterior half of carapace, distance from anterior carapace margin, 0.33–0.36. Pedipalp chela movable finger long relative to manus (MFL/ ML, 2.00–2.30). Median denticle rows of pedipalp chela fixed and movable fingers each comprising 12 oblique subrows of denticles. Pectinal tooth count, 31 (♂) and 18–20 (♀). Ventrosubmedian carinae of metasomal segments II and III each with two or three pairs of large spiniform processes ( Fig. 10C, D, G, H ). Metasomal segment IV length to width (L/W), 1.82– 1.93. Ventrolateral carinae of metasomal segment V with two or three prominent lobate processes; anal arch with three prominent spiniform lobes laterally; posteroventral margin of segment V with two prominent lobes. Telson small, wide, length to width (TL/W), 2.26–2.50 and length to height (TL/H), 2.26– 2.57 ( Fig. 10A, B, E, F ).

Affinities: Odontobuthus chabaharensis is closely related to O. odonturus , with which it shares the presence of three prominent lateral lobes on the anal arch of metasomal segment V. It differs from all other species of the genus, except O. brevidigitus , in the presence of two large conical lobes on the posteroventral margin of metasomal segment V, and from O.brevidigitus in possessing longer pedipalp chela fingers, e.g. the movable finger length to manus length (MFL/ML) is 2.00– 2.30 in O. chabaharensis compared with 1.40–1.75 in O. brevidigitus , and a lower pectinal tooth count in the female, 18–20 in O. chabaharensis compared with 20–25 in O. brevidigitus .

Description: Based on holotype ♀ (SMF) ( Figs 9A, B , 10A–D , 11A, C, E ) and paratype ♂ (ZMFUM 1324) ( Figs 9C, D , 10E–H , 11B, D, F ). As for O. baluchicus except where noted. Measurements: ♀: BL: 62.1; CL: 7.6; CWP: 8.8; CWA: 5.2; CX: 2.5; CY: 7.2; CHL: 13.5; ML: 4.5; MFL: 9.0; MtIL: 4.6; MtIH: 3.7; MtIW: 4.2; MtIIL: 5.2; MtIIH: 3.5; MtIIW: 3.9; MtIIIL: 5.6; MtIIIH: 3.3; MtIIIW: 3.6; MtIVL: 6.6; MtIVH: 3.2; MtIVW: 3.5; MtVL: 8; MtVH: 2.8; MtVW: 3.3; TL: 8.5; TW: 3.4; TH: 3.3. ♂: BL: 35.8; CL: 4.5; CWP: 5.0; CWA: 3.4; CX: 1.6; CY: 4.4; CHL: 8.6; ML: 2.6; MFL: 6.0; MtIL: 2.7; MtIH: 2.2; MtIW: 2.5; MtIIL: 3.0; MtIIH: 2.0; MtIIW: 2.3; MtIIIL: 3.2; MtIIIH: 1.9; MtIIIW: 2.1; MtIVL: 4.0; MtIVH: 1.8; MtIVW: 2.1; MtVL: 4.9; MtVH: 1.5; MtVW: 1.8; TL: 4.5; TW: 1.9; TH: 1.9. Colour: Carapace and mesosoma light brown, slightly paler ventrally; dark pigmentation around median and lateral ocelli. Legs lighter. Pectines light yellow to cream. Metasoma yellowish-brown. Telson vesicle yellow to yellowishbrown; aculeus light brown anteriorly, becoming dark brown to black posteriorly. Carapace: Trapezoid, wider than long, CWA/CL, 0.68 (♀) or 0.75 (♂), CWP/CL, 1.15 (♀) or 1.11 (♂); anterior margin moderately emarginate; median ocular tubercle situated in anterior half of carapace, CX/CL, 0.32 (♀) or 0.35 (♂), CX/CY, 0.34 (♀) or 0.36 (♂), distance between median ocelli twice ocular diameter; five pairs of lateral ocelli ( Fig. 9A, C ); anteromedian and posteromedian sulci shallow; posterolateral sulci wide, curved; carinae distinct, central lateral 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 short. Femur 3.1 (♀) or 3.4 (♂) 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. 11A, B ). Patella 2.53 (♀) or 3.06 (♂) times longer than wide; eight complete carinae; prodorsal carinae distinct (♀) or moderate (♂), granular; dorsomedian, retrodorsal, retrolateral, retroventral and ventromedian carinae obsolete to moderate, smooth ( Fig. 11C, D ); proventral and prolateral carinae comprising several spiniform granules (♂) ( Fig. 11C, D ). Chela 3.0 (♀) or 3.3 (♂) times longer than manus; manus as wide as (♂) or wider than (♀) patella; fingers 2 (♀) or 3.3 (♂) times longer than manus; median denticle subrows, including proximal subrow (left/ right) of fixed finger, 11/11 and movable finger, 12/12; all subrows except proximal flanked by prolateral and retrolateral accessory denticles; movable finger with five (♂) or six (♀) subdistal denticles, one (♀) or two (♂) prolateral and four retrolateral. Trichobothrium et adjacent to midpoint of denticle subrow 7; est adjacent to midpoint (♂) ( Fig. 11F ) or proximal end (♀) ( Fig. 11E ) of denticle subrow 9. Sternum : Type I, triangular; longer than wide; with deep median depression. Genital operculum: Completely divided longitudinally with fine, short bristles ( Fig. 9B, D ). Pectines: Distal margin extending to (♀) or beyond (♂) coxa-trochanter joint of leg IV; three marginal and seven median lamellae; fulcra present; teeth present along entire posterior margin of pecten, count (left/ right), 31/31 (♂) and 19/19 (♀). 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 granular (♀) or smooth (♂). Sternites III–VI acarinate; VII with four moderate (♀) or obsolete (♂), granular carinae, lateral carinae complete (♂) or 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 almost complete (♀) or incomplete, restricted to posterior two-thirds (♂), on segment II, incomplete, restricted to posterior half (♀) or vestigial, reduced to few granules posteriorly (♂) on III. Ventrosubmedian carinae on segments II and III each with three pairs of prominent conical, tooth-like processes. Anteroventral margins of segments III and IV each with six large, conical granules. Ventrolateral carinae on segment V dentate with (♂) or without (♀) large, subtriangular lobate processes posteriorly; anal arch with three large, conical lobes laterally and two large, conical lobes posteroventrally ( Fig. 10A–H ). Telson: Oblong-ovoid, TH/TL, 0.38 (♀) or 0.42 (♂), TW/ TL, 0.40 (♀) or 0.42 (♂); wider than metasomal segment V, TW/MtVW, 1.03 (♀) or 1.05 (♂) ( Fig. 10A, B, E, F ); dorsal surface flat, ventral surface curved, smooth (♀) or sparsely granular (♂).

Distribution: Odontobuthus chabaharensis is endemic to Iran and recorded only from Sistan and Baluchistan Province.

Additional material: IRAN: Sistan and Baluchistan Province: Parak-e Hootan road, 20 km NW of Chabahar, 25°28′N 60°33′E, 1 m, 3.iv.2018, H. Barahoei, daytime excavation, silty clay, one ♀, one juv. ( ZMFUM) ; Chabahar , N of Parak-e Sheykhan village, 25°30′N 60°35′E, 19 m, 16.xi.2018, H. Barahoei, daytime excavation, silty clay, one ♀ ( ZMFUM) ; Mekran , vii.1913, Kei, one ♂ ( ZMH) .

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 9. Odontobuthus chabaharensis. Habitus, dorsal aspect (A, C), ventral aspect (B, D). A, B, holotype ♀ (SMF). C, D, paratype ♂ (ZMFUM 1325). Scale bars = 10 mm (A, B), 5 mm (C, D).

Figure 10. Odontobuthus chabaharensis. Metasomal segment V and telson, lateral aspect (A, E), ventral aspect (B, F), metasomal segments II and III, lateral aspect (C, G), ventral aspect (D, H). A, C, E, holotype ♀ (SMF). B, D, F, paratype ♂ (ZMFUM 1325). Scale bars = 2.5 mm.

Figure 11. Odontobuthus chabaharensis. 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 1325). Scale bars = 2.5 mm (A–D), 2 mm (E, F).