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FAMILY VAEJOVIDAEGenus ParavaejovisGenus Paruroctonus

boreus infragroup

     Paruroctonus arnaudi
     Paruroctonus bantai
          Paruroctonus bantai bantai
          Paruroctonus bantai saratoga
     Paruroctonus boreus
     Paruroctonus maritimus
     Paruroctonus silvestrii
     Paruroctonus variabilis
   becki microgroup
     Paruroctonus becki
   xanthus microgroup
     Paruroctonus xanthus
   baergi microgroup
     Paruroctonus arenicola
          Paruroctonus arenicola arenicola
          Paruroctonus arenicola nudipes
     Paruroctonus baergi
     Paruroctonus boquillas
     Paruroctonus marksi
     Paruroctonus utahensis
gracilior infragroup
     Paruroctonus gracilior
stahnkei infragroup
   stahnkei microgroup
     Paruroctonus stahnkei
   shulovi microgroup
     Paruroctonus shulovi
          Paruroctonus shulovi shulovi
          Paruroctonus shuvoli nevadae
     Paruroctonus simulatus
   borregoensis microgroup
     Paruroctonus ammonastes
     Paruroctonus bajae
     Paruroctonus borregoensis
          Paruroctonus b. borregoensis
          Paruroctonus b. actites
     Paruroctonus hirsutipes
     Paruroctonus luteolus
     Paruroctonus nitidus
     Paruroctonus pseudopumilis
     Paruroctonus surensis
     Paruroctonus ventosus
   williamsi microgroup
     Paruroctonus pecos
     Paruroctonus williamsi

Genus PseudouroctonusGenus Serradigitus
Genus Smeringerus
Genus Syntropis
Genus Uroctonites
Genus Uroctonus
Genus Vaejovis
Genus Vejovoidus

Catalog of the VaejovidaeVaejovid  Bibliography

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Genus Paruroctonus Werner 1934


Paruroctonus Werner, 1934 (January?): 283, fig. 363; type species by monotypy Uroctonoides gracilior Hoffmann, 1931 [=Paruroctonus gracilior (Hoffmann, 1931)]. 


Uroctonoides Hoffmann, 1931: 405, fig. 42; type species by monotypy Uroctonoides gracilior Hoffmann, 1931 [=Paruroctonus gracilior (Hoffmann, 1931)]; preoccupied as Uroctonoides Chamberlin, 1920 (=Teuthraustes Simon, 1878) (synonymized by Werner, 1934: 283).

Hoffmanniellius Mello-Leitão, 1934a (June 30): 80 (proposed replacement name for Uroctonoides Hoffmann); type species Uroctonoides gracilior Hoffmann, 1931 [=Paruroctonus gracilior (Hoffmann, 1931)] [synonymized by Stahnke, 1957: 253 (in footnote)].


Paruroctonus: Kästner, 1941: 237; Stanhke, 1957: 253 (part); Stahnke, 1965: 262, 263 (part); Bücherl, 1971: 329; Williams, 1972: 1-3 (part; reinstated as genus); Soleglad, 1972a: 71-75 (part); Soleglad, 1973b: 353, 355 (part); Williams, 1974: 15 (part); Stahnke, 1974a: 119, 136, fig. 10; Vachon, 1974: 914, 916; Williams, 1980: 31-34, fig. 35-37 (part); Francke & Soleglad, 1981: 241, 243 (part); Sissom & Francke, 1981: 93 (part); Francke, 1985: 11, 18, 21; Sissom & Francke, 1985: 264 (part); Sissom, 1990a: 110, 114 (part); Stockwell, 1992: 408, 409, 416, 419, fig. 12, 37, 39, 58; Sissom et al., 1998: 17-19; Kovarík, 1998: 143; ICZN, 1999: 209-210; Beutelspacher, 2000: 56, 65, 152; Sissom, 2000:505-506; Soleglad & Fet, 2003a: 15, 31, 33, 36, 67, 140, 142, 163, 164, figs. 66, 79, 80, 111, D-5, Tabs. 3, 4, 9.

Hoffmanniellus (ISS): Mello-Leitão, 1945: 118; Vachon, 1963a: 163.

Vejovis (Paruroctonus): Gertsch & Allred, 1965: 4 (part); Gertsch & Soleglad, 1966: 3-7 (part); Gertsch & Soleglad, 1972: 553, 559 (part); Williams & Hadley, 1967: 112 (part); Williams, 1968a: 7 (part); Williams, 1970b: 277 (part).

Vaejovis (Paruroctonus): Hjelle, 1972: 26 (part).

Vaejovis: Díaz Najera, 1975: 3, 6 (part).

Paruroctonus (Paruroctonus): Haradon, 1983: 256; Haradon, 1984a: 205-209; Haradon, 1984b: 317-318; Haradon, 1985: 19-21.


Prosoma. –  Anterior carapacial margin straight to convex.

Mesosoma. – Pectinal tooth counts 13-39 in males, 8-24 in females. All female pectinal teeth similar in size and shape, and with sensorial areas. 

Metasoma. –  Dorsal carinae of segments I-IV with even granulation, rounded off distally.  Ventral submedian carinae of segments I-IV paired and variously developed, ranging from absent (usually on proximal segments) to granular to denticulate (strength and granulation usually increasing posteriorly).  Ventral intercarinal spaces lacking accessory setae.  Segment V with linear ventromedian carina (i.e., not bifurcated distally).

Chelicerae. –  Ventral margin of the cheliceral movable finger with or without denticles or crenulations; fixed finger lacking ventral denticles.  Serrula of movable finger absent.

Pedipalps. – Patella:  Inner face with basal tubercles moderately developed; inner longitudinal carina present, usually consisting of several granules.  Chelal carinae:  Carinal development variable, some with all carinae developed and granular to denticulate, others with various carinae reduced; sexual dimorphism prominent (females often with reduced carination). Chela dentition: Terminal denticles moderately large, conically shaped.  Chela fixed finger with primary denticle row divided into six subrows of denticles, these are flanked by six inner accessory denticles.   Chela movable finger with primary denticle row divided into six to seven subrows of denticles, these flanked by seven inner accessory denticles. Denticles of denticle row subconical, rounded to more narrow, subserrate.

Trichobothrial Pattern. –  Patella with two ventral trichobothria along ventroexternal carina (the third ventral trichobothrium is positioned on the external face). Chela with four ventral (V) trichobothria.  Chelal trichobothria ib positioned at base of fixed finger or displaced slightly from base.  Chela finger trichobothrium est about equidistant between et and esb.

Legs. –  Basitarsi and often telotarsi with setal combs.  Telotarsi ventrally with a median row of small spinules that are flanked distally by one pair of slightly larger spinules.  Ventromedian spinule row flanked laterally by setae.

Hemispermatophore. – No published observations exist.

Included groups. – gracilior, boreus, and stahnkei infragroups.

Similar taxa. – See Vejovoidus Stahnke, Paravaejovis Williams, and Smeringurus Haradon.

Distribution: Western North America, from southern Canada to Aguascalientes, Mexico.   View Map

 Remarks. - Haradon (1983, 1984a, 1984b, 1985) revised this genus and divided it into two subgenera, Paruroctonus and Smeringurus. Haradon (1984a, 1984b, 1985) further divided subgenus Paruroctonus into a number of presumably monophyletic groupings. Larger groups were referred to as infragroups (gracilior infragroup, boreus infragroup, stahnkei infragroup), for which a key was provided by Haradon (1985), and two of these were subdivided into microgroups.  The boreus infragroup includes the boreus, becki, xanthus, and baergi microgroups, and the stahkei infragroup includes the stahnkei, shulovi, borregoensis, and williamsi microgroups.  Stockwell (1992) elevated Smeringurus to genus, but it is doubtful whether either Smeringurus or Paruroctonus is monophyletic (although the group comprising Paravaejovis, Paruroctonus, Smeringurus and Vejovoidus probably is). Paruroctonus thus currently includes 29 species and 4 subspecies, all fossorial and most psammophilous, inhabiting sand dune systems throughout the deserts of the western USA and northwestern México. Some, e.g. P. gracilior, prefer packed sandy soils and even rocky or gravelly habitats. The dune systems of Chihuahua and Coahuila have not been well sampled and new Paruroctonus species may occur there. Williams (1980) published a key to the Paruroctonus of Baja California and adjacent areas.

Original Description:

Subsequent Accounts:
Williams (1980):

"Paruroctonus is distinguished from other genera in Baja California as follows: anterior margin of carapace straight or slightly convex; lateral eyes 3 per group; openings to book lungs elongate to slitlike; metasoma with ventromedian keels paired or obsolete on segments I-IV; pectines with most middle lamellae composed of small, more or less equal-sized subcircular sclerites; fulcra subtriangular; genital operculum of male with conspicuous genital papillae; chelicerae with ventral margin of movable finger armed with small inconspicuous denticles or crenulations, these usually unpigmented; pedipalp fingers with single row of primary denticles, these flanked medially by supernumerary granules: pedipalp brachium with ventral surface with two trichobothria. these near posterior margin.
The genus Paruroctonus is similar to Vaejovis in structure. Paruroctonus may generally be distinguished by the chelicerae, in which the ventral margin of the movable finger is armed with one or more denticles or crenulations (these are sometimes very lowly developed and usually unpigmented and inconspicuous). Dorsal and dorsolateral keels of the metasoma terminate posteriorly in a rounded termination (not in a sharp or angular spine or denticle).
Some 21 species have been placed in the Paruroctonus. All are from North America, the majority in desert habitats of the Mojave, Colorado, and Sonoran deserts. Ten species have been collected in northern Baja California and in adjacent regions."

 Literature Cited.

Haradon, R.M. 1983. Smeringurus, a new subgenus of Paruroctonus Werner (Scorpiones, Vaejovidae). Journal of Arachnology 11: 251–270.

Haradon, R.M. 1984a. New and redefined species belonging to the Paruroctonus borregoensis group (Scorpiones, Vaejovidae). Journal of Arachnology 12: 317–339.

Haradon, R.M. 1984b. New and redefined species belonging to the Paruroctonus baergi group (Scorpiones, Vaejovidae). Journal of Arachnology 12: 205–221.

Haradon, R.M. 1985. New groups and species belonging to the nominate subgenus Paruroctonus (Scorpiones, Vaejovidae). Journal of Arachnology 13: 19–42.

Stockwell, S.A. 1992. Systematic observations on North American Scorpionida with a key and checklist of the families and genera. Journal of Medical Entomology 29: 407–422.


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