Pseudouroctonus andreas
     Pseudouroctonus angelenus
     Pseudouroctonus apacheanus
     Pseudouroctonus bogerti
     Pseudouroctonus cazieri
     Pseudouroctonus chicano
     Pseudouroctonus glimmei
     Pseudouroctonus iviei
     Pseudouroctonus lindsayi
     Pseudouroctonus minimus
          Pseudouroctonus m. minimus
          Pseudouroctonus m. castaneus
          Pseudouroctonus m. thompsoni
     Pseudouroctonus reddelli
     Pseudouroctonus rufulus
     Pseudouroctonus savassi
     Pseudouroctonus sprousei
     Pseudouroctonus williamsi

type(s):  Holotype male from Cueva de Casa Blanca (N 29° 22’ 37.451” W 101° 02’ 15”), Municipio de Ciudad Acuña, Coahuila, México, 20 Febuary 2005 (Charley Savvas). Deposited in the Colección Nacional de Arácnidos (CNAN-T0289), IBUNAM.

Original Description:
Francke 2009:

Diagnosis.—Differs from all other Pseudouroctonus in having a single subdistal tooth on the dorsal edge of the movable finger of the chelicerae (Fig. 5); all other described species currently placed in that genus have two subdistal teeth (see “Comparisons”).
Description of the holotype (Fig.1).—Color. Medium brown, pedipalps and metasoma slightly darker, especially on the more heavily sclerotized carinae; chelicera, legs and opisthosomal venter yellow brown.
Carapace. Longer than wide. Median eyes on anterior 35%. Ocular tubercle low, without superciliary carinae. Median eyes slightly reduced in size relative to its epigean congeners; 0.2 mm in diameter. Three lateral ocelli on right side, two on left. Anterior margin broadly bilobed, with 3 pairs of setae. Entire surface with dense, minute granulation, and with scattered small and medium granules.
Tergites. Anterior half shagreened; posterior half densely, minutely granular. I-VI without carinae, VII with four longitudinal, coarsely granular carinae.
Sternum. Pentagonal, with five pairs of stout, reddish macrosetae.
Genital operculum. Each side with 6 macrosetae. Genital papillae well developed.
Hemispermatophore. Lamelliform; hooks on distal half of the lamella on a strongly sclerotized ridge adnate to it (Figs. 2-3). Hemi-mating plug strongly sclerotized, with distal barb margin smooth (Fig. 4).
Pectines. Ten teeth on each comb. Six middle lamellae on each side. Fulcra each with approximately five reddish small setae.
Sternites. Smooth except for scattered mediumsized granules along the sides. Stigmata about four times longer than wide. VII without submedian carinae; lateral carinae represented by row of few medium granules, with two stout reddish macrosetae on each one.
Metasoma. Dorsolateral carinae on I-V strong, coarsely granular. Lateral supramedian carinae on I-IV strong, coarsely granular. Lateral inframedian carinae on I strong, complete, coarsely granular; on II present on distal third to half, granular, tapering anteriorly; on III only a few medium-sized granules distally; on IV absent. Lateral median carinae on V present on basal two-thirds, moderately strong, coarsely granular. Ventrolateral carinae on I-V, ventral submedian carinae on I-IV and ventromedian carina on V strong, coarsely granular. Setation on I-IV: dorsolaterals 0,0,1,1; lateral supramedian 0,1,1,1; lateral inframedian 1,0,0,0; ventrolateral 2,2,2,2; ventral submedian 2,3,3,3. Setation on V: dorsolateral 2, lateromedian 1, ventrolateral 4, ventromedian 4. Intercarinal spaces shagreened to densely, minutely granular.
Telson. Slightly longer and wider than segment V; smooth to vestigially granular on ventrobasal region. Aculeus lacking basal microdenticles.
Chelicera. Fixed finger shorter than chela width; movable finger shorter than chela length. Chela with two macrosetae dorsally near finger articulation. Ventral edge of both fixed and movable fingers smooth; movable finger with distinct serrula.
Pedipalp femur. Dorsointernal, dorsoexternal and ventrointernal carinae strong, coarsely granular; ventroexternal carina obsolete; internomedian carina represented by few scattered granules on basal half; externomedian carina present on distal two-thirds, moderately strong, granular. Orthobothriotaxic Type C. Dorsal face flat, with dense small and medium granulation. Internal face moderately granular.
Pedipalp patella. Internomedial carina represented by 3-4 granules only, decreasing in size distally. Dorsointernal, dorsoexternal, external, ventrointernal and ventroexternal carinae strong, coarsely granular. Orthobothriotaxia C (Fig. 6). Intercarinal spaces shagreened.
Pedipalp chela (Figs. 7-9). Digital and ventromedian carinae strong, scabrous to granular; other carinae moderately strong, granular. Fixed finger with six rows of granules and six inner accessory denticles; movable finger with seven rows of granules and seven inner accessory denticles. Orthobothriotaxia C.
Leg III tarsal armature. Basitarsus with a single superior macrosetae basally (Sb of McWest), lacking the distal superior macroseta (Sd of McWest). Telotarsus with four distal spinules (sd) and lacking macrosetae promedially (pm), retromedially (rm) and retrosubterminally (rsub).
Measurements.—See Table 1.

subsequent accounts: N/A

distribution: NORTH AMERICA. Known from the type locality and from Cueva de la Azufrosa (N 28° 14’ 12.552” W 100°48’ 01.692”), Municipio de Allende, Coahuila, México

Published Records:  Five paratypes: one subadult male, two juvenile males and two juvenile females, same data as holotype (CNANT0290 to T0294).  Cueva de la Azufrosa (N 28° 10’ W 100° 45’), Municipio de Allende, Coahuila, México, collected on 29 January 2006, as follows: 1 adult female, 1 subadult female, 2 juvenile males and 1 juvenile female (C. Savvas); 2 adult females (C. Savvas and J. Krejca); 1 subadult female (P. Sprouse).

notes:  
Francke 2009:

Paratypical variability.—The variation in size among the paratypes is presented in Table 2. The larger paratypes (not adult) are straw-colored, with the pedipalp chela fingers and the aculeus darker (medium brown); the smaller paratypes are pale, cream-colored, with the pedipalp chela fingers and the aculeus light brown. Among the three paratype males, four pectinal combs have 10 teeth and two combs have 11 teeth; among the two female paratypes the four pectinal combs have 9 teeth. Like the holotype, the 12 movable fingers of the chelicera of the six paratypes have a single subdistal tooth. Likewise, the metasomal setation of the six paratypes is the same as for the holotype, except for one specimen which shows asymmetry on the dorsolaterals on II, with 0 on one side and 1 on the other (0 on all others, including the holotype).
Other specimens examined.—An additional eight specimens belonging to this species were examined, all from Cueva de la Azufrosa (N 28° 10’ W 100° 45’), Municipio de Allende, Coahuila, México, collected on 29 January 2006, as follows: 1 adult female, 1 subadult female, 2 juvenile males and 1 juvenile female (C. Savvas); 2 adult females (C. Savvas and J. Krejca); 1 subadult female (P. Sprouse). One adult female deposited at the AMNH, all others at CNAN-IBUNAM. The two males have 10 teeth on each pectinal comb (n=4); the six females have 9 teeth on each pectinal comb (n=12). All specimens have a single subdistal tooth on the movable finger of the chelicerae (n=16).
This species is dedicated to Mr. Charley Savvas, a tireless caver who collected most of the known specimens.
Comparisons.—The taxonomic history of the “uroctonoid” group of vaejovid scorpions was reviewed by Francke and Savary (2006). It currently contains three genera and 21 species: Uroctonus Thorell with 3 species, Uroctonites Williams and Savary with 4 species, and Pseudouroctonus Stahnke with 14 species. Of all the previously described species in this complex, only two have a single subdistal tooth on the movable finger of the chelicera; all others have two subdistal teeth. Those two species are currently placed in Uroctonites, namely Uroctonites sequoia (Gertsch and Soleglad) and Uroctonites montereus (Gertsch and Soleglad). These two species were originally described as belonging to Uroctonus (see Gertsch and Soleglad, 1972), and were subsequently transferred to Uroctonites when that genus was created on the basis of distinctive telotarsal armature (Williams and Savary, 1991). In addition, Williams and Savary (1991) indicated that Uroctonites shows a reduction or loss of the sclerotized mating plug of the spermatophore (or a hemi-plug in the dissection of a hemispermatophore), and the lamellar hooks on the spermatophore are located basally. Pseudouroctonus savvasi has hair-like macrosetae on the telotarsi, rather than spiniform setae; has a strongly sclerotized mating plug (Fig. 4), and has elevated lamellar hooks that are adnate to the lamella (Figs. 2-3), and thus clearly does not belong in Uroctonites, despite sharing similar cheliceral dentition with two of the four species currently placed in that genus. Pseudouroctonus savvasi appears most closely related to P. apacheanus, from which it differs, in addition to the number of subdistal teeth on the cheliceral movable finger, as follows: (a) in size (Table 1 and Fig. 10); (b) in the slight reduction of the size of the ocelli on the carapace (Figs. 11, 12); (c) on the hemispermatophores of P. savvasi the paired dorsal hooks are on a sclerotized ridge extending past the mid-point of the lamella, whereas on P. apacheanus the hooks are on the basal fifth to fourth of the lamella; (d) on adult males the ratio pedipalp chela L/carapace L in P. savvasi is approximately 2, whereas on P. apacheanus it is approximately 1.6; the ratio pedipalp chela L/chela W is 3.3 versus 2.8 (Figs. 13 and 14); and the underhand L/fixed finger length is 1.6 versus 1.3 [i.e., the chelae of P. savvasi are longer and narrower].
Remarks.—Although I did not receive any details of the scorpion collections at Cueva de la Azufrosa (Fig. 16), some interesting facts were gathered at Cueva de Casa Blanca, the type locality. First, Peter Sprouse wrote on 21 February 2005:

“We discovered a very interesting cave two days ago near Cd. Acuña, Coahuila. It has a hydrogen sulfide stream in it, and is very extensive. It also has scorpions, which appear to have only vestigial eyes ...”

Subsequently, Andy Gluesenkamp wrote on 23 February 2005:

“Charley and I saw a few individuals that escaped capture. All of them were small (1.2 cm) and very pale. All exuvia were collected under rock flakes. Most live individuals were collected either under rock flakes lying on guano; under rocks next to, or on small rock “islands” in, a small sulfurous stream below the main passage ...Charley collected one individual on a wall where it was eating a small Ceuthophilus [Orthoptera, Rhaphidophoridae]. All specimens were found roughly 30-150m from the entrance.”