Chihuahuanus, González-Santillán & Prendini, 2013

González-Santillán, Edmundo & Prendini, Lorenzo, 2013, Redefinition And Generic Revision Of The North American Vaejovid Scorpion Subfamily Syntropinae Kraepelin, 1905, With Descriptions Of Six New Genera, Bulletin of the American Museum of Natural History 2013 (382), pp. 1-71 : 24-27

Chihuahuanus , gen. nov.

Figures 1A , 2A , 4 , 7 , 16B , 17A, B , 21A , 26A , 27A ; table 1

Vaejovis bilineatus Pocock, 1898 [= Chihuahuanus bilineatus (Pocock, 1898) , comb. nov.], type species, here designated.

Vejovis first section (part): Hoffmann, 1931: 134, 139.

Vejovis spinigerus group (part): Williams, 1968: 16; 1970d: 238.

Vejovis eusthenura group (part): Williams, 1970a: 395, 396

Vejovis punctipalpi group (part): Williams, 1971a: 44–47; figs. 1, 2; table 1 .

Vaejovis eusthenura group (part): Williams, 1980: 55; Sissom and Francke, 1985: 1; Sissom, 1991: 26; Stockwell, 1992: 408, 409; Sissom, 1993: 68; Yahia and Sissom, 1996: 86; Lourenço and Sissom, 2000: 135; Sissom, 2000: 530, 532, 551; Armas and Martín-Frías, 2001: 8; McWest, 2009: 8, 48, 52, 56, 61, 64, 98, 101–103, 108, table 1 ; Ponce-Saavedra and Sissom, 2004: 541; González-Santillán, 2004: 29; Francke and Ponce-Saavedra, 2005: 67; Sissom and Hendrixson, 2005a: 131; 2005b: 33, 34; Graham and Fet, 2006: 8, 9; Fet et al., 2006a: 9, table 1 ; 2006b: 8; 2006c: 7; Graham and Soleglad, 2007: 9, 11, 12; Soleglad et al., 2007: 134, 135; Santibáñez- López and Sissom, 2010: 49.

Vaejovis punctipalpi group (part): Williams, 1971a: 37; 1971b: 44; 1980: 80; Sissom and Francke 1985: 1; Sissom, 1989: 180; 1991: 26; Stockwell, 1992: 408, 409; Sissom, 1993: 68; Lourenço and Sissom, 2000: 135; Sissom, 2000: 548, 549, 551; Armas and Martín-Frías, 2001: 1; Hendrixson, 2001: 1; McWest, 2009: figs. 322–326, tables 1 , 53, 89, 91, 93, 101–105, 108, 123; Ponce- Saavedra and Sissom, 2004: 539, 541; Sissom and Hendrixson, 2005a: 131; 2005b: 35; Soleglad and Fet, 2005: 4, 6, 7; Graham and Fet, 2006: 7, 8, 10; Fet et al., 2006a: 9, table 1 ; 2006b: 8; 2006c: 7, tables 1 , 9; Soleglad and Fet, 2006: 6, 26, tables 2 , 3 ; Graham and Soleglad, 2007: 11, 12; Soleglad et al., 2007: 134, 135.

Hoffmannius (part): Soleglad and Fet, 2008: 1 , 4, 26, 34, 38, 51, 53, 54, 57, 60, 62, 66, 67, 69, 71, 73, 74, 89–92, 96, 102; Ayrey and Soleglad, 2011: 1.

Kochius (part): Soleglad and Fet, 2008: 1 , 26, 57, 60, 89, 91, 94–96, 102; Ayrey and Soleglad, 2011: 1.

ETYMOLOGY: The generic name is a noun in apposition, masculine in gender, referring to the Chihuahuan Desert to which this genus is endemic.

DIAGNOSIS: Species of Chihuahuanus , gen. nov., may be distinguished from all other Syntropinae by the presence in adults of a small fusiform, whitish glandular area on the dorsal surface of the telson, near the base of the aculeus (fig. 26A). Species of Maaykuyak , gen. nov., also possess a gland on the dorsal surface of the telson, but it is larger, less defined, and situated medially (fig. 26B). The pedipalp chela fixed finger of Chihuahuanus , gen. nov., consistently exhibits five primary subrows of median denticles and five prolateral denticles in the median denticle row, and trichobothrium et is situated midway between RD3 and RD4 (fig. 17B). The carapace is shagreened, comprising coarse, rounded and fine, scattered granules in most species of Chihuahuanus , gen. nov. (fig. 16B).

Chihuahuanus bilineatus , comb. nov., C. coahuilae , comb. nov., C. glabrimanus , comb. nov., and C. globosus , comb. nov., resemble Mesomexovis , gen. nov., and Paravaejovis in the relative obsolescence of carinae on the pedipalp chela manus and metasoma (e.g., vl and vsm carinae). The pedipalp chelal carinae of Mesomexovis , gen. nov., and, with few exceptions, Paravaejovis are obsolete and smooth (fig. 19A–D), unlike the carinae of most species of Chihuahuanus , gen. nov., which are costate or crenulate (fig. 17A, B). The vsm carinae of metasomal segments III and IV are costate to granular, at least in the distal half, in Chihuahuanus , gen. nov. (fig. 27A), but obsolete and smooth in Mesomexovis , gen. nov., and Paravaejovis (fig. 27B, C), with few exceptions (e.g., M. atenango , comb. nov.; M. occidentalis , comb. nov.; P. confusus , comb. nov.; P. pumilis ; and P. waeringi , comb. nov.). Four species of Chihuahuanus , gen. nov. ( C. bilineatus , comb. nov.; C. coahuilae , comb. nov.; C. glabrimanus , comb. nov.; C. globosus , comb. nov.) resemble the species of Mesomexovis , gen. nov. (except M. atenango , comb. nov.) and two species of Paravaejovis ( P. gravicaudus , comb. nov.; P. spinigerus , comb. nov.) in the extensive infuscation of the carapace, tergites, and metasoma.

INCLUDED SPECIES: Chihuahuanus bilineatus (Pocock, 1898) , comb. nov.; Chihuahuanus cazieri ( Williams, 1968) , comb. nov.; Chihuahuanus coahuilae ( Williams, 1968) , comb. nov.; Chihuahuanus crassimanus (Pocock, 1898) , comb. nov.; Chihuahuanus glabrimanus (Sissom and Hendrixson, 2005) , comb. nov.; Chihuahuanus globosus (Borelli, 1915) , comb. nov.; Chihuahuanus kovariki ( Soleglad and Fet, 2008) , comb. nov.; Chihuahuanus russelli (Williams, 1971) , comb. nov.

DISTRIBUTION: Chihuahuanus , gen. nov., is endemic to the Chihuahuan Desert in Mexico (Aguascalientes, Chihuahua, Coahuila, Durango , Nuevo León, Tamaulipas, Zacatecas) and the United States (Arizona, New Mexico, Texas; fig. 4).

NATURAL HISTORY: Species of Chihuahuanus , gen. nov., occur in diverse habitats including sand dunes, shrubland, and pineoak forest, at altitudes from 530–2380 m, and have been collected under stones and on the surface at night, using UV light detecion. Although most species of the genus are lapidicolous, some species exhibit psammophilous adaptations, e.g., setal combs on the basitarsi in C. globosus , comb. nov. (fig. 21A), which are more developed in females.

REMARKS: This genus accommodates species previously assigned to Williams’ (1970a, 1971a) eusthenura and punctipalpi groups of Vaejovis , many of which were originally part of Hoffmann’s (1931) ‘‘first section’’ of that genus. Soleglad and Fet (2008) devised the names Hoffmannius and Kochius for the eusthenura and punctipalpi groups, respectively, without quantitatively testing their monophyly and composition. Both genera, as defined by Soleglad and Fet (2008), were consistently polyphyletic, and the group of species hereby assigned to Chihuahuanus , gen. nov., consistently monophyletic, in the phylogenetic analyses of González-Santillán and Prendini (in press) based on DNA and those based on morphology and DNA. Chihuahuanus bilineatus , comb. nov., C. coahuilae , comb. nov., C. glabrimanus , comb. nov., and C. globosus , comb. nov., were previously assigned to the eusthenura group ( Williams, 1970a; Lourenço and Sissom, 2000; Sissom, 2000) and then to Hoffmannius ( Soleglad and Fet, 2008) ; C. cazieri , comb. nov., C. crassimanus , comb. nov., and C. russelli , comb. nov., to the punctipalpi group ( Williams, 1971a; Lourenço and Sissom, 2000; Sissom, 2000) and then to Kochius ( Soleglad and Fet, 2008) ; and C. kovariki , comb. nov., to Kochius ( Soleglad and Fet, 2008) .

MATERIAL EXAMINED: Chihuahuanus bilineatus (Pocock, 1898) , comb. nov.: MEXICO: Tamaulipas: Municipio de Jaumave : El Salto , between Palmillas and Jaumave , 23 ° 21.4398 ′ N 99 ° 30.9408 ′ W, 1115 m, 23.viii. 2006, O.F. Francke, W.D. Sissom, G. Casper, T. Anton , V. Torti, H. Montaño , and C. Santibáñez, 18, 1♀ ( CAS [ ARA 1883 ]). Chihuahuanus cazieri ( Williams, 1968) , comb. nov.: MEXICO: Coahuila: Municipio de Cuatro Ciénegas : Cuatro Ciénegas de Carranza , 0.5 km S of town, 740 m, 28.vii.1967, S.C. Williams and W.S. Brown, holotype ♂ ( CAS Type No. 10169); Cuatro Ciénegas de Carranza, 0.5 km SW, 740 m, 28.vii.1967, S.C. Williams and W.S. Brown, 18, 1♀ paratypes ( AMNH). Chihuahuanus coahuilae ( Williams, 1968) , comb. nov.: MEXICO: Coahuila: Municipio de Cuatro Ciénegas : Cuatro Ciénegas de Carranza , 0.5 km SW, 740 m, 28.vii.1967, holotype ♂ ( CAS Type No. 10170); Ojo de Agua, Ejido El Oso , 27 ° 0.0558 ′ N 102 ° 0.2262 ′ W, 1039 m, 19.vii.2006, O.F. Francke, W.D. Sissom, K. McWest, B. Hendrixson, S. Grant, A. Jaimes, and M. Córdova, 28, 2♀ ( IBUNAM [ ARA 84 ]). Chihuahuanus crassimanus (Pocock, 1898) , comb. nov.: MEXICO: Coahuila: Municipio de Cuatro Ciénegas: Dunas de Yeso , 26 ° 51.7650 ′ N 102 ° 10.47 ′ W, 776 m, 18.vii.2006, O.F. Francke, W.D. Sissom, M. Córdova, A. Jaimes, and A. Ballesteros, 18 ( AMNH [ ARA 1105 ]); Sierra San Marcos II, 26 ° 54.7998 ′ N 102 ° 8.25 ′ W, 761 m, 18.vii. 2006, E. González, B. Hendrixson, K.J. McWest, and S. Grant, 1♀ ( AMNH [ ARA 1110 ]). Durango: Municipio de Tlahualilo: Tlahualilo de Zaragoza , ca. 15 km NW, junction Montes Claros–Tlahualilo de Zaragoza , 26 ° 9.2418 ′ N 103 ° 31.28 ′ W, 1107 m, 6.viii.2005, O.F. Francke, W.D. Sissom, K.J. McWest, C. Lee, H. Montaño, J. Ballesteros, and L. Jarvis, 18 ( AMNH [ ARA 3170 ]). U.S.A.: Texas: Hudspeth Co.: Sierra Blanca , 9 mi. W, 18.viii.1962, C.A. Triplehorn, 1♀ ( OSAL). Chihuahuanus glabrimanus (Sissom and Hendrixson, 2005) , comb. nov.: MEXICO: Guanajuato: Municipio de San Diego de la Unión : San Diego de la Unión , 8 km S, 21 ° 23.1444 ′ N 100 ° 53.4522 ′ W, 2078 m, 28.vii.2006, E. González, M. Córdova, A. Jaimes, A. Ballesteros, and O.F. Francke, 18 ( AMNH). San Luis Potosí: Municipio de Villa de Arista: Villa de Arista , 10 km E, 22 ° 30.760 ′ N 100 ° 45.499 ′ W, 30.viii.2006, O.F. Francke, W.D. Sissom, G. Casper, T. Anton , V. Torti, H. Montaño , C. Santibáñez, and A. Ballesteros, 48, 1♀ ( CAS [ ARA 1909 ]). Chihuahuanus globosus (Borelli, 1915) , comb. nov.: MEXICO: Coahuila: Municipio de Cuatro Ciénegas : Gypsum dunes, 13 km SW Cuatro Ciénegas de Carranza , 780 m, 27.vii.1967, S.C. Williams and W.S. Brown, holotype ♂ of Vaejovis gilvus Williams, 1968 ( CAS Type No. 10172). Municipio de Cuatro Ciénegas : Cuatro Ciénegas , 16 mi. SW, W point of Laguna Grande dunes, 9.viii.1968, S.C. Williams, M. Bentzien, J. Bigelow, and W.L. Minckley, 18, 1♀ ( AMNH). Municipio de Viesca: Dunas de Bilbao , 25 ° 25.5858 ′ N 102 ° 53.6538 ′ W, 1098 m, 20.vii.2006, O.F. Francke, K.J. McWest, M. Córdova, A. Jaimes, and A. Ballesteros, 48, 1♀ ( CAS [ ARA 1879 ]). Chihuahuanus kovariki ( Soleglad and Fet, 2008) , comb. nov.: MEXICO: Durango: Municipio de San Juan del Río: Hwy 137, marker km 4, between Once de Marzo and San Juan del Río , San Francisco de Lajas , 24 ° 51.764 ′ N 104 ° 38.846 ′ W, 1893 m, 10.viii.2005, O.F. Francke, W.D. Sissom, K.J. McWest, C. Lee, H. Montaño, J. Ballesteros, L. Jarvis, and C. Durán, 18 ( AMNH). Yerbanis, 80 mi. NW Durango, 19.viii.1947, W.J. Gertsch, 1♀ ( AMNH). Chihuahuanus russelli (Williams, 1971) , comb. nov.: U.S.A.: Arizona: Cochise Co. : Portal , 4770 ft, 26.viii.1965, S.C. Williams and G. Fernald, holotype ♂ ( CAS Type No. 11471). New Mexico: Rodeo, 10 mi. N, 22.ix.1963, V. Roth , 1♀ ( AMNH). Texas: Brewster Co.: Big Bend National Park, Pine Canyon Trail , Chisos Mountains , 29.2678 ° N 103.2371 ° W, 1.viii.2008, W.D. Sissom, G. Casper, and T. Anton , 28 ( AMNH).

Figures

Fig. 1. Representative species in the North American vaejovid scorpion subfamily Syntropinae Kraepelin, 1905. A. Chihuahuanus bilineatus (Pocock, 1898), comb. nov., ♀; B. Kochius bruneus (Williams, 1970), 8; C. Mesomexovis punctatus (Karsch, 1879), comb. nov., 8; D. Syntropis macrura Kraepelin, 1900, ♀; E. Thorellius sp., 8; F. Vizcaino viscainensis (Williams, 1970), comb. nov., 8. Photos in B, D and E courtesy of R. Mercurio.

Fig. 2. Representative habitats of species in the North American vaejovid scorpion subfamily Syntropinae Kraepelin, 1905. A. Cuatro Cienegas de Carranza, Coahuila, Mexico, habitat of Chihuahuanus cazieri (Williams, 1968), comb. nov., Chihuahuanus coahuilae (Williams, 1968), comb. nov., and Chihuahuanus globosus (Borelli, 1915), comb. nov. B. Death Valley, California, habitat of Kochius hirsuticauda (Banks, 1910). C. Isla Espiritu Santo, La Paz, Baja California Sur, Mexico, habitat of Kochius insularis (Williams, 1971), Paravaejovis diazi (Williams, 1970), comb. nov., and Paravaejovis gravicaudus (Williams, 1970), comb. nov. D. Cuicatlán, Oaxaca, Mexico, habitat of Mesomexovis subcristatus (Pocock, 1898), comb. nov. E. Pinacate desert, Sonora, Mexico, habitat of Paravaejovis confusus (Stahnke, 1940), comb. nov. F. West of La Paz, Baja California Sur, Mexico, habitat of Syntropis williamsi Soleglad et al., 2007. Photos in B and E courtesy of R. Mercurio and in C courtesy of I.G. Nieto.

Fig. 4. Map of southwestern North America, plotting known locality records for four genera in the vaejovid scorpion subfamily Syntropinae Kraepelin, 1905, based on data collected in the present study: Chihuahuanus, gen. nov. (squares); Konetontli, gen. nov. (triangles); Kuarapu Francke and Ponce-Saavedra, 2010 (cross); Syntropis Kraepelin, 1900 (circles).

Fig. 7. Most parsimonious tree (length: 10894.593, CI: 0.190, RI: 0.628, fit: 244.08), obtained by simultaneous phylogenetic analysis of 250 qualitative and quantitative morphological characters and 4221 aligned DNA nucleotides from three mitochondrial and two nuclear gene markers, for 18 genera and 61 species in the North American vaejovid scorpion subfamily Syntropinae Kraepelin, 1905. Analyses were conducted with an implied weighting regime (k 518) that maximized average support (González-Santillán and Prendini, in press). Synapomorphies are optimized with accelerated transformation. Black bars indicate uniquely derived apomorphic states, white bars indicate parallel derivations of apomorphic states, numbers above indicate characters, and numbers below indicate states (appendix 1).

Fig. 16. Syntropinae Kraepelin, 1905, carapace, dorsal aspect, illustrating surface ornamentation. A. Balsateres cisnerosi (Ponce-Saavedra and Sissom, 2004), comb. nov., 8 (IBUNAM). B. Chihuahuanus crassimanus (Pocock, 1898), comb. nov., 8 (AMNH). C. Kochius bruneus (Williams, 1970), 8 (AMNH). D. Konetontli acapulco (Armas and Martín-Frías, 2001), comb. nov., holotype 8 (IBUNAM). Scale bars 5 1 mm (A–C), 0.5 mm (D).

Fig. 17. Syntropinae Kraepelin, 1905, dextral pedipalp chela, dorsal (A, C) and retrolateral (B, D) aspects, illustrating carinae and distribution of trichobothria. A, B. Chihuahuanus crassimanus (Pocock, 1898), comb. nov., 8 (AMNH). C, D. Thorellius intrepidus (Thorell, 1876), 8 (AMNH). Scale bars 5 1 mm.

Fig. 21. Syntropinae Kraepelin, 1905, dextral leg III, basitarsus and telotarsus, ventral aspect, illustrating macrosetae and spinules. A. Chihuahuanus globosus (Borelli, 1915), comb. nov., 8 (AMNH). B. Thorellius intrepidus (Thorell, 1876), 8 (AMNH). C. Vizcaino viscainensis (Williams, 1970), comb. nov., 8 (AMNH). Scale bars 5 0.5 mm.

Fig. 26. Syntropinae Kraepelin, 1905, telson, dorsal aspect illustrating glandular areas on dorsal surface (demarcated by dotted lines). A. Chihuahuanus coahuilae (Williams, 1968), comb. nov., 8 (AMNH). B. Maaykuyak waueri (Gertsch and Soleglad, 1972), comb. nov., 8 (AMNH). Scale bars 5 1 mm (A), 0.5 mm (B).

Fig. 27. Syntropinae Kraepelin, 1905, metasomal segments I–V and telson, ventral aspect, illustrating carinae. A. Chihuahuanus coahuilae (Williams, 1968), comb. nov., 8 (AMNH). B. Mesomexovis punctatus (Karsch, 1879), comb. nov., 8 (AMNH). C. Paravaejovis diazi (Williams, 1970), comb. nov., 8 (AMNH). Scale bars 5 2 mm.