Alacran Francke, 1982

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 : 19-35

Alacran Francke, 1982

Alacran Francke, 1982a: 51–53 , 57, 59–61, fig. 26; type species Alacran tartarus Francke, 1982 .

Alacran : Francke, 1985: 5, 16, 19: Lourenço and Francke, 1985: 4; Francke, 1986: 8; Sissom, 1990: 109, 113; Nenilin and Fet, 1992: 10; Stockwell, 1992: 410, 412, 414, 419, figs. 24, 31, 32; Armas, 1994: 19; Kovařík, 1998: 142; Sissom and Cokendolpher, 1998: 285; Beutelspacher Baigts, 2000: 6, 13–16, 18, 48, 50, 51, 151, fig. 10, graph 1, tables 1, 2; Lourenço, 2000: 25; Lourenço and Sissom, 2000: 118; Sissom, 2000b: 496–498; Lourenço, 2001: 4; Soleglad and Sissom, 2001: 40; Soleglad and Fet, 2003a: 17, 32; 2003b: 13, 28, 32, 36, 48, 51, 67, 72, 82, 106–109, 136, 138, 141, 162, 164, tables 3, 4, 9; fig. 116; Prendini and Wheeler, 2005: 463, 468, 476–478, tables 3–5, 10; Fet and Soleglad, 2005: 12; Sissom and Hendrixson, 2005: 130; Dupre´, 2006: 2; Francke and Savary, 2006: 29; Graham and Fet, 2006: 2, 7; Volschenk and Prendini, 2008: 249; Kamenz and Prendini, 2008: 10 (table 2), 34, 44.

DIAGNOSIS: As for subfamily.

INCLUDED TAXA: Single species, Alacran tartarus Francke, 1982 .

DISTRIBUTION: Specimens of Alacran have been collected from five caves in the state of Oaxaca, southeastern Mexico (Cueva de Escorpión, Sótano Agua de Carrizo, Sótano Li Nita, Sótano de San Agustin, Te Cimutaá Cave). Alacran tartarus is known from the first four of these caves which occur in the Sistema Huautla ( Reddell, 1981), a large integrated karstic system of very deep caves on the Huautla Plateau (ca. 2000 m elevation) of the Sierra Mazateca, northern Oaxaca (fig. 1A). The fifth cave, Te Cimutaá, is a new record for the genus and may represent a new species.

ECOLOGY: Alacran tartarus , an obligate troglobite, inhabits some of the deepest caves in the world (fig. 3C, D). This species has been collected at depths of 720–916 m below the surface ( Francke, 1982a), the deepest records at which a scorpion has been found, and an order of magnitude greater than the next deepest record (275 m) for a troglobitic scorpion, Sotanochactas elliotti from El Sótano de Yerbaniz ( Francke, 1982a). The large size of Alacran (60–70 mm) is remarkable given the depths at which these scorpions live and the amounts of energy that must be transported there to support them ( Francke, 1982a). Most species of Typhlochactinae follow the usual trend toward small size in troglobitic arthropods and are less than 25 mm in length. Alacran appears to be amphibious: the second specimen from Cueva de Escorpión was collected on a wet flowstone wall (fig. 3E, F) and the specimen from Te Cimutaá Cave was found underwater in a small stream (A.G. Gluesenkamp and P. Sprouse, personal commun.).

Alacran tartarus Francke, 1982 ( Figs. 1A , 3C–F , 4 , 5A , 6A, 6B , 7A , 9A, 9B , 10A–D , 11 , 13–16 ; table 6)

Alacran tartarus Francke, 1982a: 51–57 , 59, figs. 1–17, 27, 32; table 1.

Alacran tartarus : Lourenço and Francke, 1985: 5 (table 1); Polis, 1990: 252; Nenilin and Fet, 1992: 28; Armas, 1994: 19, 21; Lourenço, 1994: 182, 183; Locket, 1995: 191; Kovařík, 1998: 142; Sissom and Cokendolpher, 1998: 289; Beutelspacher Baigts, 2000: 18, 20, 47, 51, 143, 151, map 20; Fet and Sissom, 2000: 496, 497; Lourenço and Sissom, 2000: 118; Sissom, 2000b: 498; Soleglad and Sissom, 2001: fig. 40; Volschenk et al., 2001: 161; Soleglad and Fet, 2003a: 6, figs. 8, 10; Soleglad and Fet, 2003b: 8, 76; Prendini and Wheeler, 2005: 454 (table 5), 469 (figs. 12, 13); Graham and Fet, 2006: 7; Volschenk and Prendini, 2008: 236 (table 1); Kamenz and Prendini, 2008: 10 (table 2), 44.

TYPE MATERIAL: Mexico: Oaxaca: Município de San Miguel: Holotype: 1 ♀ ( AMNH), Sótano de San Agustín [18 ° 069230 N 96 ° 479530W, 2720 m], San Agustín , 5 km SE Huautla de Jiménez, 1979 San Agustín Expedition members of the Huautla Project , Spring 1979. Paratypes: 1 juv. ³ ( AMNH), same data as holotype ; 1 ³ ( AMNH), Sótano Li Nita [18 ° 089510 N 96 ° 479560W, 2812 m], San Agustín, 5 km SE Huautla de Jiménez, B. Steele and S. Zeman, 1980 Río Iglesia Expedition , 29. III.1980 ; 1 juv. ♀ ( AMNH), Sótano Agua de Carrizo [18 ° 089160 N 96 ° 479390W, 2760 m], 5 km ESE Huautla de Jiménez, A.G. Grubbs, B. Stone, J. Smith, T. Johnson and M. McEachern , 23. V. 1978 ; 1 ♀ ( MNHN), Cueva de Escorpión [18 ° 069230 N 96 ° 479530W], San Miguel Dolina, 5 km SE Huautla de Jiménez, R. Jameson and P. Mothes, I.1978 .

DIAGNOSIS: As for subfamily.

DESCRIPTION: The following redescription supplements Francke’s (1982a) original description. It is based on the holotype, three paratypes, and six additional specimens. Only two adult males and five adult females are known (table 2).

Color: Adult (fig. 13), carapace, pedipalp femur, tergites, metasomal segments, and telson, Amber (36) with darker carinae; pedipalp patella and chela, Kingfisher Rufous (240) to Mahogany Red (132B), fingers slightly darker; chelicerae, legs, and sternites, Buff (24); pectines, Chamois (123D); cheliceral teeth, aculeus dark. Subadult (fig. 14), Sulphur Yellow (57) to Cream (54); aculeus and telotarsal ungues dark, Chestnut (32).

Chelicerae: Manus, dorsal and ventral surfaces smooth; dorsal surface with two microsetae; ventral surface with short brushlike macrosetae becoming longer on fixed finger. Fixed finger with four teeth (distal, subdistal, median and basal); median 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 five teeth (internal distal, two subdistal, median and basal; fig. 5A), internal distal tooth largest, subdistal and median teeth equal, smaller, basal tooth smallest; ventral surface with serrula, extending less than half length of finger, completely covered by long, dense macrosetae.

Carapace: Length slightly greater than anterior width (table 6). Anterior margin sublinear, without median projection (epistome); with 6–8 microsetae (fig. 6A, B). Posterior margin concave; asetose. Median and lateral ocelli absent. Median longitudinal sulcus obsolete; posterolateral sulci shallow; posteri- or transverse sulcus deep. Surface acarinate, with scattered subspiniform granules.

Pedipalps: Femur dorsoexternal, dorsointernal, ventrointernal, ventroexternal carinae distinct, comprising discontinuous rounded to spiniform granules (fig. 16A); ventroexternal carina less developed, comprising fewer granules, of similar dimensions. Dorsal surface smooth, with few granules medially; external surface granular; ventral surface with few granules proximally and small row of granules distally; internal surface smooth. Patella dorsoexternal, dorsointernal, ventroexternal, and ventrointernal carinae distinct, granular; internomedian carina comprising well-developed granular row; externomedian carinae obsolete (fig. 16B–D). Dorsal surface slightly concave and smooth except for two small granular areas surrounding trichobothria d 2 and i; external surface with several large granules, close to trichobothria; ventral surface smooth. Chela long, with relatively large, swollen manus (fig. 15). Dorsomedian, dorsal secondary, digital, ventroexternal, ventromedian and ventrointernal carinae distinct, similar, each comprising row of granules; external secondary carina distinct but weaker, comprising fewer, smaller granules; internomedian and dorsointernal carinae comprising few isolated granules between ventromedian and dorsomedian carinae. Manus, intercarinal surfaces smooth; internal surface with prominent, isolated granule near movable finger condyle and row of prominent, isolated granules from base of movable finger to base of fixed finger; fixed finger smooth. Fixed and movable fingers, median denticle row comprising six (occasionally five) and seven (occasionally six) oblique primary subrows, respectively (fig. 9A, B); internal denticles smaller than external denticles; fixed finger, terminal denticle considerably larger than preceding denticles, hooklike, fingertips interlocking unevenly when closed.

Trichobothria: Femur with three trichobothria (fig. 16A): one external (e), one dorsal (d), one internal (i). Patella with 26 or 27 trichobothria (fig. 16B–D), eight accessory (et a1, et a2, est a, em 3, em a1, em a2, esb a1, esb a2): three ventral (v 1 –v 3); 21 (rarely 19 or 20) external (et 1 –et 3, et a1, et a2, est, est a, em 1 –em 3, em a1, em a2, esb 1, esb 2, esb a1, esb a2, eb 1 – eb 5); two dorsal (d 1, d 2); one internal (i). Chela with 29 trichobothria (fig. 15), three accessory (V a, em, Em, V a): 18 on manus, five ventral (V 1 –V 4, V a), 11 external (Et 1 – Et 5, Est, Esb, Em, Eb 1 – Eb 3), two dorsal (Db, Dt); 11 on fixed finger, five external (et, est, em, esb , eb), four dorsal (dt, dst, dsb, db), two internal (it, ib). All trichobothrial areolae small, similar in diameter, trichobothrial setae similar in length (none ‘‘petite’’).

Legs: Femur and patella elongated, similar in length. Femur laterally compressed; unicarinate; dorsal and ventral surfaces separat- ed by row of distinct granules; surfaces with few macrosetae. Patella less compressed than femur; dorsal surface smooth; ventral edge granular; surfaces sparsely setose. Basitarsi prolateral, retrolateral and proventral surfaces with macrosetae, similar in number on I– III, fewer on IV; I–IV, each with large prolateral pedal spur (fig. 10A–D); I and II, proventral surface without spinules. Telotarsi, dorsomedian lobe with one large microseta; ventral surface without spinules and with at least 10 ventrosubmedian pairs of thin, acuminate macrosetae; ungues well developed, curved, equal in length; dactyl large, prominent.

Tergites: Pretergites, surfaces smooth. Posttergites I–V, surfaces smooth; VI and VII, surfaces with scattered granules posteriorly; VII, lateral margins with small spiniform granules in distal three-quarters, large sparse granules medially; I–VI, acarinate; VII, dorsosubmedian carinae vestigial, reduced to few posterior granules, dorsolateral carinae distinct, complete (fig. 13A).

Sternum: Posterior width greater than length (fig. 7A); apex rounded; lateral margins converging anteriorly; lateral lobes flat; posterior depression shallow. Surface with two macrosetae and several microsetae.

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

Pectines: Pectinal plate, surface with several macrosetae. Lamella comprising four segments (fig. 7A); surfaces with four macrosetae and several microsetae. Tooth count, 5/5–6 (³), 5/5 (♀); teeth elongated, similar in dimensions; proximal and distal teeth slightly larger; surfaces covered with microsetae.

Sternites: Anterior and posterior margins straight (posterior margin of sternite III concave in one female; fig. 13B), with few macrosetae; III and IV, surfaces almost smooth, lateral and posterior margins with very small granules; V and VI, surfaces with few granules; VII, surfaces with more granules, especially in distal half, and with pair of weakly developed ventrolateral carinae. Respiratory spiracles (stigmata) small, round, situated posterolaterally (fig. 7A).

Metasoma: Segments elongated, length greater than width (fig. 11), progressively increasing in length, decreasing in width (table 6); segment V longer than carapace. Dorsosubmedian carinae, segments I–IV, distinct, granular, distal granules not noticeably larger than preceding granules; V, absent. Dorsolateral carinae, segments I–III, obsolete, composed of sparsely distributed granules; IV, absent; V, distinct, granular. Median lateral carinae, segments I and II, distinct, granular, incomplete; III–V, absent. Ventrolateral carinae, segments I–V, distinct, granular, complete. Ventrosubmedian carinae, segments I–IV, and ventromedian carina, segment V, absent. Anal arch smooth dorsally, granular and setose ventrally. Intercarinal surfaces smooth except dorsal surfaces, segments IV and V, sparsely granular.

♀ (WDS). A, C. External aspect. B. Dorsal aspect. D. Ventral aspect. Scales 5 1 mm.

Lateral and ventral intercarinal surfaces with few microsetae, increasing in number from segments I–V.

Telson : Vesicle globose, especially in adults, slightly compressed laterally; anterodorsal lateral lobes absent (fig. 11); surface smooth with few, small granules along anterodorsal margin; few short macrosetae anteriorly; short microsetae ventrally and near base of aculeus. Aculeus very short, arising abruptly from vesicle, slightly curved.

Hemispermatophore: Lamelliform, basal portion narrow; capsular region with large, sclerotized lobe; spiniform processes absent. See Francke (1982a: 58) for illustrations.

Ontogenetic variation: Subadults and juveniles (fig. 14) differ from adults (fig. 13) as follows. Coloration of subadult and juvenile paler than adult: yellowish cream with aculeus, extremity of leg ungues, pedipalp chela denticle rows and cheliceral teeth brownish. Carapace, anterior margin with well-developed median projection (epistome) in juvenile, weakly developed to absent in adult. Pedipalp and metasomal carination largely absent in juvenile, weakly developed in subadult, well developed in adult. Surface granulation less developed in subadult and juvenile. Telson of subadult and juvenile more setose, less globose (ratio of vesicle height: length 150 % in juvenile, 100–122 % in subadult, 76–112 % in adult), with longer aculeus (table 6).

Sexual dimorphism: Adult male similar to adult female in most respects, except for slightly more pronounced carination and granulation (fig. 6A, B), completely divided genital operculum, presence of genital papillae and slightly larger pectinal teeth.

Geographical variation: Little variation among specimens from the Sistema Huautla.

REMARKS: The female paratype was listed by Francke (1982a: 55) as deposited in the author’s collection and by Fet and Sissom (2000) as deposited in the AMNH collection. The paratype is actually deposited in the MNHN.

A large, sinistral pedipalp chela, collected together with the holotype of Stygochactas granulosus from Sótano de Poncho in the neighboring state of Veracruz, is conspecific with the latter species and not with Alacran tartarus , with which it was compared by Sissom and Cokendolpher (1998: 289). See remarks to S. granulosus for details.

DISTRIBUTION: Specimens of A. tartarus have been collected from four caves of the Sistema Huautla (figs. 1A, 3C–F) in the state of Oaxaca, southeastern Mexico (Cueva de Escorpión, Sótano Agua de Carrizo, Sótano Li Nita, Sótano de San Agustín).

ECOLOGY: As for genus.

ADDITIONAL MATERIAL: Mexico: Oaxaca: Município de San Miguel: 2 ♀ ( WDS), Sótano de San Agustín [18 ° 069230 N 96 ° 479530W, 2720 m] Section, Sistema Huautla, A.G. Grubbs, J.H. Smith and F. Holliday, V.1985 ; 1 juv. ♀ ( AMNH), Sótano Li Nita [18 ° 089510 N 96 ° 479560W], San Agustín, 5 km SE Huautla de Jiménez, White Room Lead , 2871 m, M. Minton, 22. III.1981 ; 1 ♀ ( AMNH), Sótano Li Nita [18 ° 089510 N 96 ° 479560W], 2916 m, San Agustín, 5 km SE Huautla de Jiménez, M. Minton, L. Wilk and R. Simmons , 1. IV.1981 ; 1 ³ ( AMNH), leg ( AMCC [ LP 3499 ]), Cueva de Escorpión , 18 ° 069230 N 96 ° 479530W, 1561 m, A. Gluesenkamp, P. Sprouse and C. Savvas, 18.IX.2004 .

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. 3. Type localities and habitats of Typhlochactidae Mitchell, 1971. A, B. La Cueva de la Mina (Tamaulipas, Mexico), type locality of Typhlochactas rhodesi Mitchell, 1968: entrance (A); main chamber (B). C–F. Cueva de Escorpión (Oaxaca, Mexico), type locality of Alacran tartarus Francke, 1982: lake in front of entrance (C); descent (D); A. tartarus ³ (AMNH) collected from flowstone wall (E); A. tartarus ³ (AMNH) habitus, in life (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. 11. Alacran tartarus Francke, 1982, paratype ³ (AMNH), metasoma and telson, lateral aspect. Scale 5 5 mm.

Fig. 13. Alacran tartarus Francke, 1982, ♀ (AMNH), habitus. A. Dorsal aspect. B. Ventral aspect. Scale 5 1 cm.

Fig. 14. Alacran tartarus Francke, 1982, juv. ³ paratype (AMNH), habitus. A. Dorsal aspect. B. Ventral aspect. Scale 5 1 cm.

Fig. 15. Alacran tartarus Francke, 1982, sinistral pedipalp chela showing carinae and distribution of trichobothria. A. Paratype ³ (AMNH). B–D.

Fig. 16. Alacran tartarus Francke, 1982, ♀ (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 1 mm.