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FAMILY VAEJOVIDAEGenus ParavaejovisGenus ParuroctonusGenus Pseudouroctonus

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

Catalog of the VaejovidaeVaejovid  Bibliography

Why study vaejovids?



Genus Pseudouroctonus Stahnke 1974 


Pseudouroctonus Stahnke, 1974: 119, 132, fig. 7E, 9A-B; type species Vaejovis reddelli Gertsch & Soleglad, 1972 [=Pseudouroctonus reddelli (Gertsch & Soleglad, 1972)].


Vaejovis (part): Williams, 1980: 48-55 (part), 74-79 (V. minimus group); Sissom, 1990a: 109, 111, 114; Williams & Savary, 1991: 284 (V. minimus group).

Uroctonus (part): Sissom, 1990a: 109, 111, 114.

Pseudouroctonus: Sissom, 1990a: 114; Stockwell, 1992: 409-410, 416, 419 Kovarνk, 1998: 144; Sissom, 2000:514-515; Soleglad & Fet, 2003a: 15,  28, 31, 33, 36, 58, 67, 86, 103, 140, 142, 145, 163, 164, figs. 66, 79, 80, 111, D-3, Tabs. 3, 4, 9.


Prosoma. –  Anterior carapacial margin with shallow to deep rounded anterior median indentation.

Mesosoma. – Pectinal tooth counts 8-19 in males, 7-16 in females. All female pectinal teeth similar in size and shape, and with sensorial areas.

Metasoma. –  Dorsal carinae of segments I-IV with angular termination, distalmost denticle variable in size.  Ventral submedian carinae of segments I-IV paired, crenulate to serrate (smooth on I in P. reddelli).  Segment V with ventromedian carina linear (i.e., not bifurcated distally).

Chelicerae. –  Ventral margin of the cheliceral movable finger smooth, with crenulations, or with denticles; fixed finger with (P. cazieri, P. reddelli) or without ventral denticles.  Serrula well developed distoventrally on movable finger.

Pedipalps. –  Patella:  Inner face with basal tubercles moderately developed; inner longitudinal carina vestigial, represented by only one or two small granules.  Chelal carinae:  Ventromedian carina absent, producing flattened ventral chelal face (except in P. reddelli and P. minimus).  Carinae well developed and granular, except in a few species (e.g., females of V. minimus).  Chela dentition: Terminal denticles not prominent, conically shaped.  Chela fixed finger with primary denticle row divided into five to six subrows of denticles, these are flanked by six inner accessory denticles.  Chela movable finger with primary denticle row divided into six or seven subrows of denticles, these flanked by six to seven inner accessory denticles.  Denticles of primary denticles row subconical, rounded.

Trichobothrial Pattern.  Patella with two ventral trichobothria along ventroexternal carina (the third ventral trichobothrium is positioned on the external face).  Four or five V trichobothria on chela manus.  Chelal trichobothrium ib situated at distal end of palm near the level of the articular membrane or on extreme base of fixed finger. Chela finger trichobothrium est about equidistant between et and esb.

Legs. –  Basitarsi and telotarsi without setal combs.  Telotarsi ventrally with a median row of small spinules that are flanked distally by a pair of slightly larger spinules.  Ventromedian spinule row flanked laterally by setae.

Hemispermatophore. – Mating plug present, ental process with smooth margin.  Lamellar hook two-pronged, elevated from base of distal lamina.

Included species. – P. andreas (Gertsch & Soleglad 1972); P. angelenus (Gertsch & Soleglad 1972); P. apacheanus (Gertsch & Soleglad 1972); P. bogerti (Gertsch & Soleglad 1972); P. cazieri (Gertsch & Soleglad 1972); P. chicano (Gertsch & Soleglad 1972); P. glimmei (Hjelle 1972); P. iviei (Gertsch & Soleglad 1972); P. lindsayi (Gertsch & Soleglad 1972); P. minimus (Kraepelin 1911) with three subspecies, P. m. minimus (Kraepelin 1911), P. m. castaneus (Gertsch & Soleglad 1972), P. m. thompsoni (Gertsch & Soleglad 1972); P. reddelli (Gertsch & Soleglad 1972);P. rufulus (Gertsch & Soleglad 1972); P. sprousei Francke and Savary 2006;P. williamsi (Gertsch & Soleglad 1972).

Similar taxa. – See Uroctonus Thorell, Uroctonites Williams & Savary, and Vaejovis C. L. Koch (mexicanus group).

Remarks. - As originally construed (Stahnke 1974), this genus was monotypic. Sissom (1990) questioned its validity, but it was accepted and expanded by Stockwell (1992) to include most of the formerly Vaejovis minimus group species, and presently comprises 13 species (one with 3 subspecies).  Williams & Savary (1991) commented on the phylogenetic relationships of the uroctonoids and illustrated hemispermatophores for several species of Pseudouroctonus.

Owing to the uncertainty in our understanding of vaejovid phylogeny, further investigation is warranted to clarify relationships of these species, the monophyly of which remains untested. There is no key for this genus in its current state. Workers must resort to the key to Uroctonus of Gertsch & Soleglad (1972) for distinguishing some of its component species. Pseudouroctonus reddelli, from south central Texas, is a common inhabitant of caves. It also occurs in epigean habitats, and may be found under rocks among litter on wooded slopes. The other species assigned here occur under rocks and fallen logs or in crevices in boulders and outcrops on rocky slopes (lower and higher elevations), often under fairly mesic conditions.

Williams (1980), prior to the expansion of Pseudouroctonus by Stockwell (1992) referred the following five Baja California species to the 'minimus' subgroup of Vaejovis: V. minimus castaneus, V. andreas, V. lindsayi, V. montcazieri, and V. rufulus. He distinguished the group from other groups as follows: "carapace with frontal margin usually deeply bilobed; genital operculum of female not completely fused longitudinally; pedipalp with hand heavy, flattened, and wide; ratio of palm width to palm depth usually greater than 1.05; pectine usually small,  usually supported by 9 or fewer middle lamellae; pectine teeth 7-12 in females, 8-13 in males; movable finger of pedipalp distinctly shorter than carapace; pedipalp fingers not terminating distally in enlarged clawlike tooth.

Literature Cited:

Gertsch, W.J. & Soleglad, M.E. 1972. Studies of North American scorpions of the genera Uroctonus and Vejovis. Bulletin of the American Museum of Natural History 148: 549–608.

Sissom, W.D. 1990. Systematics, biogeography and paleontology. In: Polis, G.A. (Ed.) The Biology of Scorpions. Stanford University Press, Stanford, CA, 64–160.

Stahnke, H.L. 1974. Revision and keys to the higher categories of Vejovidae. Journal of Arachnology 1: 107–141.

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.

Williams, S. C. and W. E. Savary.  1991.  Uroctonites, a new genus of scorpion from western North America (Scorpiones:  Vaejovidae).  Pan-Pacific Entomologist, 67: 272-287.



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