Sotanochactas Francke, 1986

Vignoli, Valerio & Prendini, Lorenzo, 2009, Systematic Revision Of The Troglomorphic North American Scorpion Family Typhlochactidae (Scorpiones: Chactoidea), Bulletin of the American Museum of Natural History 2009 (326), pp. 1-94 : 38-46

Sotanochactas Francke, 1986

Sotanochactas Francke, 1986: 5 , 8; type species Typhlochactas elliotti Mitchell, 1971 [5 Sotanochactas elliotti ( Mitchell, 1971) ].

Sotanochactas : Lourenço and Francke, 1985: 4 (nomen nudum); Sissom, 1988: 365; 1990: 109, 113; Polis, 1990: 253; Stockwell, 1992: 410, 412– 414, 419, figs. 10, 34; Kovařík, 1998: 142; Sissom and Cokendolpher, 1998: 285; Beutelspacher Baigts, 2000: 6, 13–16, 18, 20, 48, 53, 57, 151, fig. 11B, C, graph 1, tables 1, 2; Lourenço, 2000: 25; Lourenço and Sissom, 2000: 118; Sissom, 2000b: 498; Lourenço, 2001: 4; Soleglad and Sissom, 2001: 40; Soleglad and Fet, 2003a: 7, 16–17, 32, fig. 12; 2003b: 36, 72, 74, 82, 106– 109, 141, 162, tab. 9; Fet et al., 2004: 197; Prendini and Wheeler, 2005: 454, 458, 460, 468, 470, 476, tab. 9, 10, figs. 18, 19; Fet and Soleglad, 2005: 12; Sissom and Hendrixson, 2005: 130; Dupre´, 2007: 10; Francke and Savary, 2006: 29; Graham and Fet, 2006: 2; Volschenk and Prendini, 2008: 249.

DIAGNOSIS: Sotanochactas is the sister taxon of a monophyletic group comprising Stygochactas and Typhlochactas (fig. 4), from which it may be separated on the basis of the following combination of characters. Size small, total length (adult) less than 25 mm. Cheliceral fixed finger with four teeth (subdistal present); median and basal teeth not fused into a bicusp; movable finger with four dorsal teeth (one subdistal present). Carapace, anterior margin, median projection (epistome) present. Pedipalps greatly elongated, chela fingers twice as long as manus. Pedipalp femur, ventroexternal carina, and patella, internomedian carina, distinct. Pedipalp chela, dorsal secondary, digital, ventroexternal, ventromedian, and ventrointernal carinae absent or obsolete. Chela fixed and movable fingers, median denticle rows comprising six and five oblique primary subrows, respectively; basal primary subrows considerably longer than other subrows; terminal denticle of fixed finger slightly larger than preceding denticles, fingertips interlocking evenly when closed. Patella trichobothrium v 1 situated distal to trichobothrium esb 1. Chela fixed finger, external trichobothria situated in distal half of finger, trichobothrium eb situated midway on finger; trichobothrium it situated midway along finger; trichobothrium ib situated midway in proximal third of finger. Legs without prolateral pedal spurs. Basitarsi I and II, proventral surfaces with short row of closely aligned spinules subdistally. Telotarsi, ventral surface without ventromedian row of spinules. Sclerites of genital operculum (♀) fused, but loosely connected by membrane along entire length of suture. Tergite VII, dorsolateral carinae distinct, complete. Metasomal segments I–IV, dorsosubmedian carinae distinct; I–III, dorsolateral carinae distinct; I, median lateral carinae obsolete, incomplete; I–V, ventrolateral carinae obsolete (I) to distinct (II–V); V, ventromedian carina obsolete.

INCLUDED TAXA: Monotypic genus: Sotanochactas elliotti ( Mitchell, 1971) .

DISTRIBUTION: Endemic to Mexico. Recorded from San Luis Potosí.

Sotanochactas elliotti ( Mitchell, 1971) ( Figs. 1B , 2C–F , 4 , 5B , 6C , 7B , 9C, 9D , 10E–H , 12A , 17–19 ; table 7)

Typhlochactas elliotti Mitchell, 1971: 135–147 , figs. 1–17, 26, 27, table 1.

Typhlochactas elliotti : Reddell and Mitchell, 1971: 144, fig. 1; Reddell, 1973: 33, 37; Reddell and Elliott, 1973: 171; González-Sponga, 1974: 56; Soleglad, 1976: 253; Mitchell and Peck, 1977; 159, 164, 167, 168; Lourenço, 1981: 660; Red-

TABLE 7 Meristic data for Sotanochactas elliotti ( Mitchell, 1971) , Stygochactas granulosus ( Sissom and Cokendolpher, 1998) and Typhlochactas sissomi Francke et al., 2009 Measurements (mm) follow Francke et al. (2009). Abbreviations as follows: AMNH 5 American Museum of Natural History, New York; IBUNAM 5 Instituto de Biología, Universidad Nacional Autonóma de México, Mexico City; MNHN 5 Muséum National d’Histoire Naturelle, Paris; WDS 5 W. David Sissom Private Collection, Canyon, TX

TABLE 7 (Continued)

dell, 1981: 36, 115, fig. 17; Francke, 1982a: 51, 59, 60, figs. 18–21, 26, 28, 33; 1986: 5, 8; Sissom, 1988: 365; Sissom and Cokendolpher, 1998: 285; Lourenço and Sissom, 2000: 118.

Typlochactas elliotti : Díaz Najera, 1975: 3, 30.

Sotanochactas ellioti : Lourenço and Francke, 1985: 5 (table 1); Armas, 1994: 21; Kovařík, 1998: 142; Beutelspacher Baigts, 2000: 18, 53, 54, 145, 151, map 22.

Sotanochactas elliotti : Francke, 1986: 7, 8, figs. 11– 13; Polis, 1990: 253 (fig. 6.4); Lourenço, 1994: 182, 183; Sissom, 2000b: 498; Soleglad and Sissom, 2001: 40, fig. 41; Volschenk et al., 2001: 161; Soleglad and Fet, 2003a: fig. 12; 2003b: 30, 32, 76; Vignoli and Kovařík, 2003: 131; Özkan and Karaer, 2004: 57; Prendini and Wheeler, 2005: table 5; Volschenk and Prendini, 2008: 236 (table 1).

Typhlochactas ellioti : Beutelspacher Baigts, 2000: 20, 53.

TYPE MATERIAL: Mexico: San Luis Potosí: Município de Ciudad Valles: Holotype: 1 subad. ³ ( AMNH), El Sótano de Yerbaniz, 21 km N Ciudad Valles, Sierra de El Abra [22 ° 119070 N 98 ° 599120W], ca. 250 m, W. R. Elliott, 31.VII.1969. Paratypes: 1 juv. ♀ ( MNHN RS 5376 ), same locality, W. R. Elliott, 27.III.1970 ; 1 ³ ( WDS), same locality, R. W. Mitchell, 4.VII.1970 .

DIAGNOSIS: As for genus.

DESCRIPTION: Mitchell (1971: 144) listed a holotype and two paratypes: a possible immature female (MNHN), marked with a questionmark, and another specimen, alive when the paper was published and the sex of which was given as undetermined, but which was, in fact, an adult male. Mitchell’s (1971) description was based on the subadult male holotype. Francke (1982a) subsequently illustrated the hemispermatophore of the adult male paratype. We present the first description of the adult male (fig. 17), supplementing Mitchell’s (1971) original description of the subadult male and Francke’s (1982a) description of the hemispermatophore.

Color: Mitchell (1971) described the living specimens as almost transparent and lacking pigmentation. Coloration of preserved specimens as follows (fig. 17). Holotype, uniformly Cinnamon (123A). Paratype ³ (WDS), chelicerae, carapace and pedipalps, Chamois (123D); mesosoma and metasoma, Clay (123B); legs, Cream (54); telson similar to but slightly darker than legs; cheliceral teeth, pedipalp finger denticle rows, leg ungues and dactyl, and aculeus, reddish.

Chelicerae: Manus, dorsal and ventral surfaces smooth; dorsal surface with several microsetae, two larger microsetae situated near base of fixed finger; movable finger, dorsal surface with six microsetae. Fixed finger, dorsal margin with four teeth (distal, subdistal, median, and basal; fig. 5B); medi- an and basal teeth not fused into bicusp; distal tooth largest, subdistal and median teeth equal, smaller, basal tooth smallest. Movable finger, internal distal and external distal teeth opposable, internal distal tooth completely overlapping external distal tooth in dorsal view; dorsal margin with four teeth (internal distal, subdistal, median, and basal), internal distal tooth largest, subdistal and median teeth equal, smaller, basal tooth smallest; ventral surface with long serrula, extending distal three-quarters of finger, tines increasing in size distally, covered by dense brush of macrosetae.

Carapace: Length considerably greater than anterior width (table 7). Anterior margin weakly convex, with small median projection (epistome) (fig. 6C). Posterior margin convex; asetose. Median and lateral ocelli absent. Median longitudinal sulcus well developed; posterolateral sulci obsolete; posterior transverse sulcus deep. Surface acarinate, uniformly finely granular, especially along median longitudinal sulcus. Surface and margins with several microsetae.

Pedipalps: Pedipalps greatly elongated, slender (figs. 18, 19). Femur, ventroexternal carina distinct, granular, other carinae obsolete (fig. 19A). Dorsal surface with scattered granules on proximal three-quarters, becoming smooth distally; external and internal surfaces smooth; ventral surface granular proximally, becoming smooth distally. Dorsal, external, and internal surfaces each with several long microsetae; ventral surface asetose. Patella, dorsointernal carina distinct, granular; dorsoexternal, ventroexternal, and ventrointernal carinae obsolete; internomedian carina comprising row of granules; externomedian carinae absent (fig. 19B–D). Dorsal and external surfaces smooth; internal surface with scattered granules and long microsetae. Chela fingers very elongated, movable finger longer than carapace, more than twice length along ventroexternal carina (table 7); manus width greater than or equal to height. Dorsal secondary, digital, external secondary, and ventrointernal carinae absent; ventroexternal and ventromedian carinae obsolete; other carinae absent (fig. 18). Chela manus, intercarinal surfaces smooth except for few small round granules on dorsal surface near base of fixed finger; internal surface with few granules except for prominent, isolated granule near movable finger condyle; fixed finger smooth. Manus and fingers, internal surfaces with several microsetae, often associated with median denticle row. Fixed finger, median denticle row comprising six oblique primary subrows, basal subrow very long (fig. 9C); internal denticles larger than external denticles, large internal denticle present between terminal and subterminal subrows, other four internal denticles smaller; terminal denticle of fixed finger slightly larger than preceding denticles, fingertips interlocking evenly when closed. Movable finger, median denticle row comprising five oblique primary subrows, basal subrow very long (fig. 9D).

Trichobothria: Femur with three trichobothria (fig. 19A): one external (e), one dorsal (d), one internal (i). Patella with 19 trichobothria (fig. 19B–D), five petite (d 1, d 2, et 2, esb 2, eb 2), one accessory (em 3): two ventral (v 1, v 2); 14 external (et 1 –et 3, est, em 1 –em 3, esb 1, esb 2, eb 1 – eb 5); two dorsal (d 1, d 2); one internal (i). Chela with 26 trichobothria (fig. 18), seven petite (V 1, Et 4, Et 5, Esb, Db, esb , db): 16 on manus, four ventral (V 1 –V 4), 10 external (Et 1 – Et 5, Est, Esb, Eb 1 – Eb 3), two dorsal (Db, Dt); 10 on fixed finger, four external (et, est, esb , eb), four dorsal (dt, dst, dsb, db), two internal (it, ib).

Legs: All segments smooth except for femur ventral surface, covered by stout granules increasing in size and density from legs I–IV. Dorsal and ventral surfaces with few short microsetae; basitarsi sparsely setose, setae more numerous on legs I and II. Basitarsi I–IV without prolateral pedal spurs (fig. 10E–H); I and II, proventral surface with short subdistal row of closely aligned spinules. Telotarsi, dorsomedian lobe with one large microseta; ventral surface without spinules, and with six submedian pairs of subspiniform macrosetae; ungues well developed, curved, equal in length; dactyl four times shorter than ungues.

Tergites: Pretergites, surfaces smooth. Posttergites with few microsetae, especially on posterior and lateral margins, granulation and setation increasing posteriorly; I–VI acarinate, surfaces finely granular; VII with small depression posteromedially, lateral and dorsolateral surfaces granular, more pronounced than on preceding tergites, dorsosubmedian carinae vestigial, reduced to few posterior granules, dorsolateral carinae distinct, complete (fig. 17A).

Sternum: Length greater than posterior width (fig. 7B); apex rounded; lateral margins converging anteriorly; lateral lobes flat; posterior depression shallow. Surface with eight macrosetae and several scattered microsetae.

Genital operculum: Sclerites (³) completely divided; genital papillae protruding distinctly beyond posterior edges (fig. 7B). Sclerites (♀) fused, but loosely connected by membrane along entire length of suture.

Pectines: Pectinal plate, surface with two macrosetae situated mediolaterally. Lamella comprising three segments (fig. 7B), demarcated by very faint sutures; surfaces with few setae. Tooth count, 4–5/4–5; teeth elongated; proximal and distal teeth slightly larger.

Sternites: Posterior margin III, slightly concave (holotype) or sublinear, of other sternites convex. Surfaces acarinate (fig. 17B), smooth ; VI and VII, lateral margins with small granules; VII, surface and posterior margin with microsetae. Respiratory spiracles (stigmata) small, round, situated posterolaterally.

Metasoma: Segments elongated, length greater than width (fig. 12A), progressively increasing in length, decreasing in width (table 7); segment V equal to or longer than carapace. Dorsosubmedian carinae, segments I–IV, distinct, granular, distal granules not noticeably larger than preceding granules; V, absent. Dorsolateral carinae, segment I, obsolete, granular, complete; II and III, obsolete, granular, incomplete; IV, absent; V, obsolete, granular. Median lateral carinae, segment I, distinct, granular, incomplete; II– V, absent. Ventrolateral carinae, segment I, obsolete, granular; II–V, distinct, composed of small, stout granules, complete. Ventrosubmedian carinae, segments I–IV, absent. Ventromedian carina, segment V, distinct, granular in anterior half of segment, becoming obsolete, sparsely granular posteriorly. Dorsal intercarinal surfaces, segments I–IV, slightly concave; V, convex. Intercarinal surfaces smooth except segment I, with few large granules. Dorsolateral carinae and lateral intercarinal surfaces with long microsetae; ventral intercarinal surfaces with at least three paired macrosetae.

Telson : Vesicle elongated, width equal to height (table 7), flattened dorsally, rounded ventrally; anterodorsal lateral lobes absent (fig. 12A); surface smooth, almost entirely covered in long macrosetae, except medially on dorsal surface. Aculeus long, moderately sclerotized, gently curved.

Hemispermatophore: Lamelliform; broad trunk, with long narrow prominence, originating in capsular region, bearing small, strongly sclerotized lobe; spiniform processes absent. See Francke (1982a: 58) for illustrations.

Ontogenetic variation: Subadult and juvenile paratypes completely whitish, ungues and cheliceral teeth only slightly darker at extremities, aculeus light reddish. Pedipalp and metasomal carinae less pronounced; all surfaces smooth.

Sexual dimorphism: Adult female unknown. Males exhibit completely divided genital operculum and genital papillae.

Geographical variation: All specimens from same locality.

REMARKS: The juvenile ♀ paratype (MNHN) is damaged. The metasoma is broken, and the left pedipalp, legs I, II, and IV, are lost.

DISTRIBUTION: Known only from the type locality, El Sótano de Yerbaniz, a vertical cave in the Sierra de El Abra karstic region, San Luis Potosí, central Mexico (figs. 1B, 2C–F).

ECOLOGY: According to the original description, the holotype and one paratype of this troglobitic species were collected within 1 or 2 m of one another in a small, wet limestone tunnel about 75 m below the cave entrance ( Mitchell, 1971). No data were provided for the third specimen, except that it was collected in the same cave. This species is considered the most troglomorphic member of the family, on account of the pronounced attenuation of its pedipalps ( Francke, 1982a).

Figures

Fig. 1. Map of Mexico, showing the known localities of Typhlochactidae Mitchell, 1971. A. Known localities of Alacraninae, new subfamily: Type locality of Alacran tartarus Francke, 1982, on the Huautla Plateau, Oaxaca (1); Te Cimutaá Cave, Oaxaca, a new record for the genus possibly representing a new species of Alacran Francke, 1982 (2). B. Type localities of Typhlochactinae Mitchell, 1971: Sotanochactas elliotti (Mitchell, 1971), El Sótano de Yerbaniz, San Luis Potosí (1); Stygochactas granulosus (Sissom and Cokendolpher, 1998), Sótano de Poncho, Veracruz (2); Typhlochactas cavicola Francke, 1986, Cueva del Vandalismo, Tamaulipas (3); Typhlochactas mitchelli Sissom, 1988, Cerro Ocote, Oaxaca (4); Typhlochactas reddelli Mitchell, 1968, La Cueva del Ojo de Agua de Tlilapan, Veracruz (5); Typhlochactas rhodesi Mitchell, 1968, La Cueva de la Mina, Tamaulipas (6); Typhlochactas sissomi Francke et al., 2009, Cañada de La Joya, Queretaro (7); Typhlochactas sylvestris Mitchell and Peck, 1977, 25 km S Valle Nacional, Oaxaca (8).

Fig. 2. Type localities and habitats of Typhlochactidae Mitchell, 1971. A, B. La Cueva del Ojo de Agua de Tlilapan (Veracruz, Mexico), type locality of Typhlochactas reddelli Mitchell, 1968: lake in front of entrance (A); entrance (B). C–F. El Sótano de Yerbaniz (San Luis Potosí, Mexico), type locality of Sotanochactas elliotti (Mitchell, 1971): entrance (C, D); descent (E); horizontal tunnel (F). Photos courtesy P. Spouse and A. G. Gluesenkamp.

Fig. 4. Single most parsimonious tree (312 steps, CI: 57, RI: 56) obtained by cladistic analysis of 142 morphological characters (appendix 1) scored for nine taxa in the family Typhlochactidae Mitchell, 1971, and three outgroup taxa under weighting regimes that maximized fit and minimized length (Prendini et al., 2009). Unambiguous synapomorphies are indicated with bars. Solid bars indicate uniquely derived apomorphic states, whereas empty bars indicate parallel derivations of apomorphic states. The number above each bar gives the character number, the number below gives the character state.

Fig. 5. Typhlochactidae Mitchell, 1971, chelicerae, dorsal aspect. A. Alacran tartarus Francke, 1982, paratype ³ (AMNH). B. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS). C. Stygochactas granulosus (Sissom and Cokendolpher, 1998), juv. ³ holotype (AMNH). D. Typhlochactas cavicola Francke, 1986, holotype ♀ (AMNH). E. Typhlochactas mitchelli Sissom, 1988, holotype ³ (AMNH). F. Typhlochactas reddelli Mitchell, 1968, holotype ♀ (AMNH). G. Typhlochactas rhodesi Mitchell, 1968, holotype ♀ (AMNH). H. Typhlochactas sissomi Francke et al., 2009, subad. ³ holotype (IBUNAM), dextral chelicera. I. Typhlochactas sylvestris Mitchell and Peck, 1977, holotype ♀ (AMNH), sinistral chelicera. Scales: A 5 1 mm; B–H 5 0.1 mm.

Fig. 6. Typhlochactidae Mitchell, 1971, carapace, dorsal aspect. A. Alacran tartarus Francke, 1982, paratype ³ (AMNH). B. Alacran tartarus Francke, 1982, ♀ (WDS). C. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS). D. Stygochactas granulosus (Sissom and Cokendolpher, 1998), juv. ³ holotype (AMNH). Scales: A, B 5 1 mm; C, D 5 0.5 mm.

Fig. 7. Typhlochactidae Mitchell, 1971, sternum, genital operculum and pectines, ventral aspect. A. Alacran tartarus Francke, 1982, ♀ (WDS). B. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS). C. Typhlochactas rhodesi Mitchell, 1968, holotype ♀ (AMNH). Scales: A 5 1 mm; B, C 5 0.5 mm.

Fig. 9. Typhlochactidae Mitchell, 1971, dextral pedipalp chela fixed (left) and movable (right) fingers, dentition patterns. A, B. Alacran tartarus Francke, 1982. C, D. Sotanochactas elliotti (Mitchell, 1971). E, F. Stygochactas granulosus (Sissom and Cokendolpher, 1998). G, H. Typhlochactas cavicola Francke, 1986. I, J. Typhlochactas mitchelli Sissom, 1988. K, L. Typhlochactas reddelli Mitchell, 1968. M, N. Typhlochactas rhodesi Mitchell, 1968. O, P. Typhlochactas sissomi Francke et al., 2009. Q, R. Typhlochactas sylvestris Mitchell and Peck, 1977.

Fig. 10. Typhlochactidae Mitchell, 1971, sinistral legs I–IV, basitarsi and telotarsi, retrolateral aspect. A–D. Alacran tartarus Francke, 1982, ♀ (WDS). E–H. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS). I–L. Stygochactas granulosus (Sissom and Cokendolpher, 1998), juv. ³ holotype (AMNH). Scales: A 5 0.1 mm; B, C 5 0.5 mm.

Fig. 12. Typhlochactinae Mitchell, 1971, metasoma and telson, lateral aspect. A. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS). B. Stygochactas granulosus (Sissom and Cokendolpher, 1998), juv. ³ holotype (AMNH). C. Typhlochactas cavicola Francke, 1986, holotype ♀ (AMNH). D. Typhlochactas mitchelli Sissom, 1988, holotype ³ (AMNH). E. Typhlochactas reddelli Mitchell, 1968, holotype ♀ (AMNH), segments IV, V and telson only. F. Typhlochactas rhodesi Mitchell, 1971, holotype ♀ (AMNH). G. Typhlochactas sylvestris Mitchell and Peck, 1977, holotype ♀ (AMNH). Scales 5 1 mm.

Fig. 17. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS), habitus. A. Dorsal aspect. B. Ventral aspect. Scale 5 1 mm.

Fig. 18. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS), sinistral pedipalp chela showing carinae and distribution of trichobothria. A. Dorsal aspect. B. External aspect. C. Ventral aspect. Scale 5 0.5 mm.

Fig. 19. Sotanochactas elliotti (Mitchell, 1971), paratype ³ (WDS), sinistral pedipalp femur (A) and patella (B–D) showing carinae and distribution of trichobothria. A, B. Dorsal aspect. C. External aspect. D. Ventral aspect. Scales 5 0.5 mm.