Hadogenes polytrichobothrius, PRENDINI, 2006

PRENDINI, LORENZO, 2006, New South African Flat Rock Scorpions (Liochelidae: Hadogenes), American Museum Novitates 3502 (1), pp. 1-32 : 10-23

Hadogenes polytrichobothrius , new species

Hadogenes bicolor Purcell, 1899 : Hewitt, 1918: 160, 161 (part), pl. 30, figs. 88, 89.

Hadogenes longimanus Prendini, 2001: 158 , 159 (part), 161, fig. 1 (part), tab. 2 (part).

TYPE MATERIAL: SOUTH AFRICA: Mpumalanga Province: Lydenburg District : Holotype? ( AMNH), Steelpoort, 9 km

SE on road to Lydenburg [Farm Olifantspoortjie 319, 248459S 308189E], i.2003, I. Engelbrecht and B. Watkins, in rock cracks. Paratypes: same data as holotype, 1?, 6/ ( AMNH) , 1 juv. ( AMCC 138999 ) ; Steelpoort [248439S 308129E], J. Visser, 2? ( SAMC C4275 [JV 1844], C4276 [JV 1850]), 1/ ( SAMC C4281 [JV 1846]), 1 juv.? ( SAMC C3901 [JV 1836]); same data, except ‘‘ i.2003, I. Engelbrecht and B. Watkins, in rock crack’’, 1/ ( AMNH) ; Farm Steelpoortpark 362, turn­off to Lydenburg , koppies on left side of road 555, 24852.5109S 30802.8129E, 5.ii.2005, L. Prendini and K.M.A. Prendini, 840 m, in crack of granite rock in very dry, mixed bushveld, 1 juv.? ( AMNH) ; Farm Olifantspoortjie 319, entrance gate, 24846.4359S 30815.9519E, 5.ii.2005, L. Prendini and K.M.A. Prendini, 969 m, in crevices of granite outcrops in very dry, mixed bushveld, 1 subad.? 1 juv.? ( AMNH) , 1 juv.? ( AMCC 145221 ) . Belfast District: Doornkop [Doringkop, on Farm Doornkop 356, 258309S 298559E], near Belfast, R. Gerhardt, 1? [damaged] ( AMGS) . Middelburg District: Mapoch’s Grotte on Farm 500, at bottom of hill near entrance gate, 25810.6759S 29857.1399E, 5.ii.2005, L. Prendini and K.M.A. Prendini, 1407 m, in crevices of granite rocks at base of koppie, mixed bushveld, drier than upslope, 3/ ( AMNH) . Limpopo Province: Sekhukhuneland District: Potlake Nature Reserve ( Farm Jagdlust 418), 24815.1609S 29854.6499E, 6.ii.2005, L. Prendini and K.M.A. Prendini, 844 m, in crevices in sandstone at base of southern slope of mountains, mixed bushveld, 1 subad.? ( AMNH) ; same data, except ‘‘ Potlake Nature Reserve (Farm Wintersveld 417), 24815.8459S 29857.0219E, 791 m’’, 1? 2/ 2 subad.? 1 subad. / ( AMNH) , 1 subad. /, 1 juv.?, 10 juv., disarticulated chela ( AMCC 145222 ) .

DIAGNOSIS: Hadogenes polytrichobothrius is placed in the bicolor group on account of the shape of metasomal segment I, which is wider than it is high posteriorly. It appears to be the sister species of H. longimanus : both are characterized by the presence of five or more trichobothria on the internal surface of the pedipalp chela, a pronounced lobe, distal to the notch in the fixed finger of the pedipalp chela of adult males and females, and a relatively short metasoma in the adult male (ca. 53–57% of the total length), compared with most other Hadogenes species (including H. newlandsi and H. soutpansbergensis ). The latter two characters are shared with H. bicolor , suggesting that the three species collectively form a monophyletic group, to the exclusion of H. newlandsi and H. soutpansbergensis .

Hadogenes polytrichobothrius is distinguished from H. bicolor , H. newlandsi , and H. soutpansbergensis by the presence of five or more internal trichobothria on the pedipalp chela; in the other species, there are only two internal trichobothria. It is distinguished from H. longimanus by its shorter, broader pedipalps (especially the chelae), displaced lobe on the movable finger of the pedipalp chela of the adult male, and higher trichobothrial counts. This species has the greatest number of trichobothria thus far recorded in Hadogenes ( Newlands, 1980; L. Prendini, unpublished data): up to 237 trichobothria per pedipalp.

ETYMOLOGY: The species name refers to the high trichobothrial counts of this species, which are the highest recorded in the genus.

DESCRIPTION: The following description, based on the holotype male (AMNH; figs. 2, 3 ) and a paratype female from 9 km SE of Steelpoort (AMNH; figs. 4, 5 ), complements previous descriptions ( Hewitt, 1918; Prendini, 2001a) of the first specimen collected, from Doornkop, near Belfast (AMGS), and four specimens from Steelpoort (SAMC C3901, C4275, C4276, C4281). Measurements and counts are recorded from 4? (table 4) and 13/ (table 3).

Color: Chelicerae, pedipalp chelae, legs, and distal third of tergites slightly paler, and contrasting with carapace, rest of pedipalps, tergites, and metasoma. Telson (?) distinctly paler than metasomal segments I–V. Sternites distinctly paler than tergites and metasoma. Chelicerae, pedipalp chelae, legs, and telson (/), Clay Color 26; carapace, pedipalp patellae and femora, Raw Sienna 136; tergites I–VI, proximal two­thirds, sternite VII, metasoma, Brownish Olive 29; tergites I–VI, distal third, pectines, genital operculum, and sternites, Raw Umber 123; telson (?), Buff 124.

Carapace: Three pairs of lateral ocelli, slightly smaller than median ocelli ( figs. 6, 7 ). Median ocular tubercle with superciliary carinae well developed, protruding above ocelli, and interocular sulcus distinct. Anterior margin of carapace with median notch well developed, triangular inset situated far back, with frontal lobes protruding anteriorly. Anteromedian sulcus deep, suturiform, furcating anteriorly around triangular inset. Median longitudinal suture distinct, continuous from anterior furcated sutures, through ocular tubercle to posterior furcated sutures, which converge on ocular tubercle from posterior carapace margin. Posterior furcated sutures obsolete, discontinuous. Posteromedian and posteromarginal sulci distinct, shallow. Paired median lateral and posterolateral sulci also distinct, shallow. Carapace entirely granular, except for surfaces of frontal lobes, median lateral, posterolateral and posteromarginal sulci, which are smooth. Granulation almost uniformly fine, becoming coarser on anterocular and anterolateral surfaces.

Chelicerae: Movable finger with distal internal tooth slightly smaller than distal external tooth, and opposed. Ventral aspect of fingers and manus with long, dense macrosetae.

Pedipalps: Femur with four distinct carinae ( fig. 12 ); ventroexternal carina obsolete, reduced to a few granules proximally; dorsoexternal carina, dorsointernal and ventrointernal carinae costate granular, composed of large, heavily sclerotized granules; externomedian carina comprised of spiniform granules; dorsal, dorsoexternal and ventral intercarinal surfaces finely and uniformly granular; internal intercarinal surfaces smooth, except for a few scattered spiniform granules. Femur width 39.5% (33–46%) of length (tables 3, 4).

Patella with six distinct carinae ( figs. 13– 15 ); dorsoexternal carina obsolete; dorsointernal and ventrointernal carinae costate to costate granular; internal carinae costate granular, composed of very large, heavily sclerotized spiniform granules, converging at apex of anterior process; externomedian and ventroexternal carinae granular; dorsoexternal and ventral intercarinal surfaces finely and uniformly granular, becoming granuloreticulate on ventral surfaces; internal intercarinal surfaces smooth, except for a few scattered granules; anterior process strongly developed. Patella width 61.5% (56–67%) of length.

Chela with three distinct carinae; dorsal secondary and digital carinae obsolete ( figs. 16, 17 ); external secondary carina strongly developed, costate granular; ventroexternal carina strongly developed, crenulate, aligned parallel to longitudinal axis of chela, with distal edge disconnected from external movable finger condyle and directed toward a point between external and internal movable finger condyles, but closer to external condyle ( fig. 19 ); ventromedian carina obsolete, reduced to a vestigial granule proximally; ventrointernal carina also obsolete; internomedian and dorsointernal carinae weakly developed, each comprised of a series of isolated spiniform granules; dorsomedian carina strongly developed, composed of a continuous double row of spiniform granules; dorsal intercarinal surfaces smooth to weakly reticulate, becoming finely granular externally (?), smooth to uniformly finely granular (/); external intercarinal surfaces coarsely granular ( fig. 18 ); dorsointernal intercarinal surfaces with scattered spiniform granules, becoming finely granular on internal surface of fixed finger; ventrointernal intercarinal surfaces smooth. Chela with pronounced, conical lobe on movable finger, fitting unevenly into corresponding notch in fixed finger of adult?, i.e. displaced to external surface and overlapping, when fingers closed; fixed finger additionally with pronounced, conical lobe distal to notch, and smaller, rounded lobe proximally. Dentate margins of chela fingers with double row of denticles, fused proximally at lobe/notch and also distally. Chela height 47% (38–56%) of width; chela width 66.5% (60–73%) of length along ventroexternal carina; length movable finger 104% (97–111%) of length along ventroexternal carina.

Trichobothria: Neobothriotaxic major, type C ( figs. 12–19 ; tables 3, 4), with the following segment totals: femur, 3 (1 d; 1 i; 1 e), patella, 82–121 (2 d; 1 i; 28–43 v; 51– 75 e) and chela, 75–113 (66–101 manus; 13– 16 fixed finger, including 5–8 i). Total number of trichobothria per pedipalp, 160–237. Only femoral trichobothria, trichobothria in the d and i series of the patella, and trichobothria in the D, d, and e series of the chela are stable in number and distribution. External and ventral trichobothria of the chela and patella are numerically and distributionally too variable for diagnostic purposes. This species is characterized by the presence of 5– 8 accessory trichobothria in the i series of the chela.

Mesosoma: Tergites each with paired submedian depressions and obsolete median carina. Pre­tergites of? and / smooth and shiny. Post­tergites I–VI smooth and shiny in?, except for very fine and even granulation on anteromedial surfaces (excluding median carina and submedian depressions, which are smooth) and lateral surfaces; VII sparsely and coarsely granular anteriorly, becoming smooth posteriorly in?; post­tergites of / smooth and shiny. Sternites smooth and shiny, each with paired longitudinal depressions internal to spiracles; VII with pair of shallow posterolateral oval depressions in?, and pair of obsolete carinae, converging distally towards shallow notch in distal apex ( figs. 10, 11 ). Sternite VII length 92.5% (85– 100%) of width in?, 76.5% (66–87%) in / (tables 3, 4).

Pectines: Mesial margin of first proximal median lamella of each pecten angular, with pectinal teeth present along entire posterior margin in? ( fig. 8 ); mesial margin of first proximal median lamella shallowly curved, with proximal fifth of posterior margin devoid of teeth in / ( fig. 9 ). Pectinal teeth (left/ right): 21–24/20–23 (?), 16–21/16–20 (/).

Sternum: Subpentagonal, type 2. Median longitudinal furrow deep and narrow along entire length ( figs. 8, 9 ).

Genital operculum: Suboval, completely divided longitudinally, with genital papillae present (?). Subcordate, partially connected by a membrane in anterior two­thirds, with distinct distal lobes in posterior third, and with genital papillae absent (/).

Legs: Femora each with paired granular carinae on ventral surface, becoming less developed on posterior legs. Basitarsi each with few spiniform setae on prolateral and retrolateral margins, decreasing in number from anterior to posterior legs. Telotarsi each with two rows of three ventrosubmedian spiniform setae and basal row of ventromedian spinules. Telotarsal laterodistal lobes truncat­ ed; median dorsal lobes extending to ungues. Telotarsal ungues short, distinctly curved, and equal in length. Retrolateral pedal spurs absent.

Metasoma and telson: Metasomal segment I posterior height 88.5% (78–99%) of width (tables 3, 4). Metasomal segments I–V progressively increasing in length, and decreasing in width, segment V width 68.5% (57– 78%) of segment I width. Metasoma slender, width percentage of length for segment I, 30% (23–37%) in?, 42% (32–52%) in /; for II, 19.5% (17–22%) in?, 27.5% (23– 32%) in /; for III, 18% (15–21%) in?, 26% (22–30%) in /; for IV, 16.5% (14–19%) in?, 23.5% (20–27%) in /; and for V, 15.5% (12–19%) in?, 21% (17–25%) in /. Telson vesicle width 112.5% (103–122%) of metasomal segment V width; globose in?, oval in /, with flattened dorsal surface and round­ ed ventral surface ( fig. 33 ), height 33% (25– 41%) of length. Aculeus short, 25% (19– 31%) of vesicle length, and sharply curved. Total length of metasoma 115.5% (111– 120%) of combined length of prosoma and mesosoma in?, but 85% (78–92%) in /.

Eight carinae on segment I, six carinae on segments II–IV, and five carinae on segment V ( figs. 20, 21 ). Dorsosubmedian carinae of segment I becoming obsolete distally, but distinct throughout length of segments II–V. Median lateral carinae fully developed on segment I, but absent from segments II–V. Segments I–IV with closely paired ventrosubmedian carinae, fused into a single ventromedian carina on segment V. Median lateral and dorsosubmedian carinae costate on segment I, dorsosubmedian carinae costate to costate granular on segments II–V (/), composed of spiniform granules on segments II– V (?). Dorsosubmedian carinae of metasomal segments II and III each terminating distally with enlarged, spiniform granule; dorsosubmedian carinae of other metasomal segments without spiniform granules distally. Ventrosubmedian and ventrolateral carinae costate on segment I, costate to costate granular on segments II–IV. Ventrolateral and ventromedian carinae of segment V composed of spiniform granules. Intercarinal surfaces smooth, except for lateral surfaces of segments III–V in?. Telson smooth, sparsely covered in long macrosetae.

Hemispermatophore: Doubled hook near base of distal lamella; distal crest truncate ( figs. 22, 23 ).

Geographic variation: Specimens collect­ ed at the northernmost locality record, Potlake Nature Reserve, display longer, narrow­ er pedipalps and a more slender metasoma than specimens collected further south in the distributional range (tables 3, 4).

Ontogenetic variation: The presence of a lobe on the movable finger of the pedipalp chela and a corresponding notch in the fixed finger ( figs. 16, 17 ) are indicative of sexual maturity in most species of Hadogenes (Lawrence, 1966; Newlands and Prendini, 1997; Prendini, 2001a). The lobe and corresponding notch are absent from the fingers of the pedipalp chela in subadults and juveniles, developing in the final instar of species, such as H. polytrichobothrius , in which these characters are present in adults.

In the specimens of Hadogenes examined for this study, sexual maturity was assessed by the presence of a lobe and notch in males and females, and by the presence of fully developed paraxial organs in males, and ovari­

/ (AMNH). 20. Lateral aspect, /. 21. Lateral aspect,?. Scale bar 5 10 mm.

uterus or the gravid condition in females. The elongated metasoma (longer than the combined length of prosoma and metasoma), a secondary sexual characteristic only acquired in the final instar male ( Lamoral, 1979; Newlands, 1980; Prendini, 2001a), is a further indication that male specimens are adult ( fig. 21 , cf. female, fig. 20 ). In all species of Hadogenes , juvenile males and females resemble each other, and adult females, very closely in general morphological features (besides the absence of a lobe and notch on the pedipalp chela fingers) until the final instar. The metasoma of the juvenile male is also shorter than the combined length of the prosoma and mesosoma.

Sexual dimorphism: The characters of primary external sexual dimorphism are the undivided genital operculum, which opens in a single flap, in the female ( fig. 9 ), compared with the two unconnected sclerites, which open independently and cover a pair of genital papillae, in the male ( fig. 8 ). Secondary sexual characters observed in adult males, compared with adult females and juveniles of both sexes, are as follows (tables 3, 4): more pronounced lobes on the fixed and movable fingers of the chela, and a more pronounced notch in the fixed finger; slightly flatter pedipalp chelae; metasoma elongated, longer than the combined length of the prosoma and mesosoma ( fig. 21 ); increased granulation of the carapace ( fig. 6 ), tergites and metasoma; reduced granulation on the pedipalp chelae; greater number of pectinal teeth ( fig. 8 ).

Remarks: The male specimen from Doornkop near Belfast (AMGS), described as H. bicolor by Hewitt (1918), and provisionally assigned to H. longimanus by Prendini (2001a), is conspecific with H. polytrichobothrius , as are the four specimens from Steelpoort (SAMC C3901, C4275, C4276, C4281), also provisionally assigned to H. longimanus by Prendini (2001a). The correct georeference for Doornkop [Doringkop, on Farm Doornkop 356], in the Belfast District, has been established as 258309S 298559E. The georeference assigned by Prendini (2001a: 159), i.e. 258559S 308169E, refers to another Doornkop, in the Carolina District. That particular locality was visited during 2001 and no Hadogenes were found there.

DISTRIBUTION: Hadogenes polytrichobothrius is endemic to rocky outcrops and ridges in the Steelpoort River valley and the middle Olifants River valley, of the Limpopo Province (Sekhukhuneland District) and Mpumalanga Province (Belfast, Lydenburg, Middelburg districts), South Africa ( fig. 1 ). The southernmost locality record, Doornkop [258309S 298559E], is approximately 150 km southwest of the northernmost record in the Potlake Nature Reserve [24815.1609S 29854.6499E].

The known locality records of H. polytrichobothrius fall within the following range of altitudes (percentage of locality records indicated in parentheses): 500 –1000 m (62.5%), 1000–1500 m (25%), 1500–2000 m (12.5%).

The distributional range falls mostly (87.5%) within the Mixed Bushveld vegetation zone ( Van Rooyen and Bredenkamp, 1998a) of the Savanna biome ( Rutherford and Westfall, 1994; Low and Rebelo, 1998). However, the record from Doornkop falls close to the boundary of the Moist Sandy Highveld Grassland vegetation zone ( Bredenkamp and Van Rooyen, 1998) in the Grassland biome ( Rutherford and Westfall, 1994; Low and Rebelo, 1998).

The annual rainfall in the region inhabited by this species varies from less than 650 mm in the north of the distributional range, to 950 mm in the south, and is received mostly in the summer (December to May). Temperatures range from 2108C to 408C ( Bredenkamp and Van Rooyen, 1998; Van Rooyen and Bredenkamp, 1998a).

ECOLOGY: In common with all other species of Hadogenes , H. polytrichobothrius is an obligate lithophile ( Prendini, 2001b). This species inhabits the narrow cracks and crevices of weathered granite and sandstone outcrops on gently sloping hillsides at moderate altitudes in the Steelpoort River valley and the middle Olifants River valley. Its distributional range is allopatric with that of its closest relative, H. longimanus , which inhabits rocky outcrops along the upper reaches of the Olifants River valley, running parallel, further to the south and west ( Prendini, 2001a). It is also allopatric with H. bicolor , which occurs at higher altitudes along the Drakensberg escarpment, further north and east.

Another liochelid, Opisthacanthus validus Thorell, 1876 , was collected in sympatry with H. polytrichobothrius at Mapoch’s Grotte but the two species were not syntopic. Opisthacanthus validus occupied humid habitats in the shade of dense vegetation upslope, whereas H. polytrichobothrius occupied dri­ er, unshaded habitats at the base of the slope. A scorpionid, Opistophthalmus glabrifrons Peters, 1861 , is the only other scorpion species thus far recorded in sympatry with H. polytrichobothrius (I. Engelbrecht, personal commun.).

CONSERVATION STATUS: Hadogenes polytrichobothrius is presently known from eight localities, falling within seven QDS. As with many other species of Hadogenes in southern Africa, this species is threatened by habitat destruction. Steelpoort, the type locality of the species, is an open­cast vanadium mine. At least six other large mines and several granite quarries are situated in the Steelpoort River valley, between Doornkop and Steelpoort. Most of the remaining land is privately owned and cattle farming (rangeland) is the dominant land­use. Much of the rangeland in the northern part of this species’ range (part of the former ‘‘Independent Homeland’’ of Lebowa) is severely degraded by overgrazing and soil erosion. Although one population of H. polytrichobothrius is protected in the Potlake Nature Reserve, the threat of mining, quarrying, and other forms of habitat degradation, together with the restricted distributional range of this species, which otherwise falls entirely outside of existing protected areas, warrants its assignment to the Vulnerable IUCN Red List Category. This species is characterized by an acute restriction in both its area of occupancy and number of known localities. It would thus be prone to the ef­ fects of human activities (or stochastic events, the impact of which is increased by human activities) within a very short period of time in an unforeseeable future, and is capable of becoming Critically Endangered or even Extinct in a very short period.

Figures

Fig. 1. Map showing the known distribution of species in the bicolor group of Hadogenes: H. bicolor Purcell, 1899 (square), H. longimanus Prendini, 2001 (cross), H. newlandsi Prendini, 2001 (star), H. polytrichobothrius n.sp. (triangle) and H. soutpansbergensis n.sp. (circle). Contour interval, 500 m.

Figs. 2–5. Hadogenes polytrichobothrius n.sp., habitus of holotype? and paratype / (AMNH). 2. Dorsal aspect,?. 3. Ventral aspect,?. 4. Dorsal aspect, /. 5. Ventral aspect, /. Scale bars 5 10 mm.

Figs. 6–11. Hadogenes polytrichobothrius n.sp., carapace, pectines and sternites of? and / paratypes (AMNH). 6. Carapace,?. 7. Carapace, /. 8. Pectines and basal piece,?. 9. Pectines and basal piece, /. 10. Sternite VII,?. 11. Sternite VII, /. Scale bars 5 5 mm.

Figs. 12–15. Hadogenes polytrichobothrius n.sp., carinae, trichobothria and macrosetae on dextral pedipalpal segments of paratype / (AMNH). 12. Femur, dorsal aspect. 13. Patella, dorsal aspect. 14. Patella, external aspect. 15. Patella, ventral aspect. Scale bar 5 5 mm.

Figs. 16–19. Hadogenes polytrichobothrius n.sp., carinae, trichobothria and macrosetae on dextral pedipalpal segments of? and / paratypes (AMNH). 16. Chela, dorsal aspect,?. 17. Chela, dorsal aspect, /. 18. Chela, external aspect, /. 19. Chela, ventrointernal aspect, /. Scale bar 5 5 mm.

Figs. 28–33. Hadogenes soutpansbergensis n.sp., carapace, pectines, and sternites of? and / paratypes (AMNH). 28. Carapace,?. 29. Carapace, /. 30. Pectines and basal piece,?. 31. Pectines and basal piece, /. 32. Sternite VII,?. 33. Sternite VII, /. Scale bars 5 5 mm.

Figs. 20–21. Hadogenes polytrichobothrius n.sp., metasoma and telson of holotype? and paratype

Figs. 22–23. Hadogenes polytrichobothrius n.sp., hemispermatophore of paratype? (AMNH). 22. Ectal aspect. 23. Ental aspect. Scale bar 5 1 mm.