Vizcaino, 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 : 55-56

Vizcaino , gen. nov.

Figures 1F , 6 , 7 , 20C , 21C ; table 1

Vejovis viscainensis Williams, 1970 [= Vizcaino viscainensis (Williams, 1970) , comb. nov.], type species, by monotypy.

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

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

ETYMOLOGY: The generic name is a noun in apposition, masculine in gender, taken from the Vizcaino Desert in the Baja California Peninsula, to which this monotypic genus is endemic.

DIAGNOSIS: Vizcaino , gen. nov., is unique among Syntropinae in possessing four primary subrows of median denticles, separated by five retrolateral denticles, in the median denticle row of the pedipalp movable finger (fig. 20C); the terminal subrow, comprising one to three denticles in the other genera of Syntropinae , is absent (figs. 17A, C, 18A, 19A, C, 20A–C). The following combination of characters is also unique for the genus: pedipalp femur, rlv carina smooth and costate; legs I–III, basitarsi (male and female) laterally compressed, each with dorsal and retrodorsal macrosetae elongated and arranged into a sublinear row, forming a setal comb (fig. 21C); legs I–IV, telotarsi each with basal, ventromedian and distal series of spinules slender and elongate (fig. 21C); metasomal segments I–IV, vsm carinae distinct (protruding above adjacent intercarinal surfaces) and finely denticulate.

Vizcaino , gen. nov., appears superficially similar to some species of Chihuahuanus , gen. nov., and Paravaejovis (e.g., C. globosus , comb. nov., P. pumilis , and, to a lesser extent, other species of Paravaejovis in the Baja California Peninsula) with which it shares setal combs on the basitarsi of legs I–III (fig. 21C). In addition to the abovementioned characters, Vizcaino , gen. nov., differs from these taxa by possessing elongated pedipalp chela fingers, such that trichobothrium eb is situated on the fixed finger between RD6 and RD7, it is situated on the fixed finger between PD5 and PD6, and ib is situated on the fixed finger, at or close to PD6. Trichobothrium eb is situated at RD7, it at PD6 and ib between PD6 and PD 7 in Chihuahuanus , gen. nov., and most species of Paravaejovis , except P. confusus , comb. nov., and related species in which the positions of these trichobothria are similar to those of Vizcaino , gen. nov. Paravaejovis confusus , comb. nov., and related species are readily distinguished from Vizcaino , gen. nov., by the dentition of the pedipalp chela movable finger, and the telotarsal spinules.

Vizcaino , gen. nov., shares with Konetontli , gen. nov., Kuarapu , Maaykuyak , gen. nov., Syntropis , Chihuahuanus bilineatus , comb. nov., C. coahuilae , comb. nov., and Thorellius cristimanus the presence of a secondary hook on the hemispermatophore (fig. 8H), created by an extension of the axial carina of the distal lamina, that forms a pronounced bifurcation with the primary hook.

INCLUDED SPECIES: Vizcaino viscainensis (Williams, 1970) , comb. nov.

DISTRIBUTION: Vizcaino , gen. nov., is endemic to the Vizcaino Desert of the Baja California Peninsula, Mexico, and recorded from the states of Baja California and Baja California Sur (fig. 6).

NATURAL HISTORY: According to Williams (1970b), this species is rarely collected, and may have limited surface activity, spending most of its life inside burrows. The known specimens were collected at night with UV light detection on sparsely vegetated, semistabilized sand dunes, from sea level to 262 m altitude. This species appears to be more abundant in areas where coastal fog is frequent. The habitat and habitus, especially the setal combs and elongated spinules on the leg tarsi, and the pale, immaculate integument are consistent with the psammophilous ecomorphotype ( Prendini, 2001a).

REMARKS: Williams (1980) originally placed this species in the eusthenura group of Vaejovis , for which Soleglad and Fet (2008) devised the name Hoffmannius , without quantitatively testing either its monophyly or composition. Hoffmannius , as defined by Soleglad and Fet (2008), was consistently polyphyletic in the phylogenetic analyses by González-Santillán and Prendini (in press). Vizcaino , gen. nov., was not related to the species assigned to Hoffmannius by Soleglad and Fet (2008), forming a monophyletic group with Syntropis instead (fig. 7). The creation of a monotypic genus for this species is based on its phylogenetic position and unique, diagnostic character combination.

MATERIAL EXAMINED: Vizcaino viscainensis (Williams, 1970) , comb. nov.: MEXICO: Baja California: Municipio de Ensenada: Miller’s Landing, 2 mi. NW, 25 ft, 21.vi.1968, S.C. Williams and M.A. Cazier, holotype ♂ of V. viscainensis ( CAS Type No. 10429). Baja California Sur: Municipio de Mulegé: Las Bombas, 3.2 km E, 30 m, 16.iv.1969, S.C. Williams, 2♀ ( AMNH); Sierra del Placer, 21 km to junction Bahía Tortugas and Bahía Asunción, 98 km E of Vizcaino towards Bahía Tortugas, 27 ° 28.9278 ′ N 114 ° 17.0928 ′ W, 262 m, 28.vi.2008, H. Montaño and E. González, 88, 6♀, 13 juv. ( AMNH [ ARA 2855 ]), 88, 6♀ ( IBUNAM [ARA 2245]).

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. 6. Map of southwestern North America, plotting known locality records for three genera in the vaejovid scorpion subfamily Syntropinae Kraepelin, 1905, based on data collected in the present study: Maaykuyak, gen. nov. (squares); Mesomexovis, gen. nov. (circles); Vizcaino, gen. nov. (triangles).

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. 20. Syntropinae Kraepelin, 1905, dextral pedipalp chela movable finger, dorsal aspect, illustrating dentition. A. Balsateres cisnerosi (Ponce-Saavedra and Sissom, 2004), comb. nov., 8 (IBUNAM). B. Thorellius intrepidus (Thorell, 1876), 8 (AMNH). C. Vizcaino viscainensis (Williams, 1970), comb. nov., 8 (AMNH). Scale bars 5 0.5 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.