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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

Why study vaejovids?

Paruroctonus silvestrii ((Borelli 1909)

Vejovis silvestrii Borelli, 1909: 225-227; Ewing, 1928: 14
Vaejovis silvestrii
: Ewing, 1928: 14; Hjelle, 1972: 6, 23-26, 27, fig. 11, 47, 48, 51.
Vejovis boreus
(part; MIS): Gertsch, 1958: 6.
(Paruroctonus) silvestrii: ►Gertsch & Soleglad, 1966: 15-20, fig. 1, 4, 5, 7, 9, 27, 28.
Paruroctonus silvestrii
: Williams, 1972: 3, 4, 8; Soleglad, 1973b: 355; Williams, 1976: 2; Williams, 1980: 32, 39-41, fig. 39, 46; Hjelle, 1982: 98; Haradon, 1985: 24, 40; Williams, 1987b: 329; Kovarík, 1998: 144; Beutelspacher, 2000: 69, 136, 146, 152, map 39; Sissom, 2000:508; Soleglad & Fet, 2003b: 6, fig. 7; Soleglad & Fet, 2003a: 8, 67, 150, figs. 107, B-1.

Paruroctonus silvestrii (Borelli), female.  Photograph by W. David Sissom

type(s):  Vejovis silvestrii Borelli 1909: Holotype (female) from Sierra Madre, Los Angeles County, California, USA in the Museo Zoologico, Turin, Italy.

subsequent accounts:
Gertsch and Soleglad 1966

DIAGNOSIS: Distinct species (figs. 4, 5) resembling boreus in general appearance but differing in following features: carapace heavily mottled with black pattern and tergites of preabdomen having transverse black bands continuous to posterior margins. Females attaining larger size, having shorter and stouter cauda with heavier telsons, and longer and less granulose hands on chelae. Sexual dimorphism more pronounced, and considerably smaller males having more slender cauda and quite thin, weak hands. Ventral surfaces of cauda bearing one more pair of setae on each segment. Eyes of medium size and somewhat smaller than those of boreus.
COLORATION: Similar to that of boreus in both sexes but more boldly marked in black. Base color yellow to dull orange or tan, with well marked black pattern as shown in figures 7 and 9. Eyes and eye tubercles black. Carapace typically bright yellow, with intricate pattern of black bands and stripes radiating from pale midline. Tergites I-VI of preabdomen with transverse black bands covering most of surface, dark to posterior margins; each tergite enclosing pair of oval yellow markings near center and irregular series of spots on each side. Tergite VII much paler than tergites in front, without pronounced pattern. Cauda yellow to orange, unmarked above, but with series of four dusky lines below on segments I-IV as in boreus; these markings in some cases faint or lacking, but well indicated in many females and broader and darker in many males.
STRUCTURE: Similar to that of boreus except as indicated below. Males much smaller than females, with proportionately thinner cauda. Measurements given in table 2.
Carapace: Shape of carapace of female from northeast of Lucia, Monterey County, California: Anterior margin straight, set with six suberect bristles; width at side eyes four-sevenths of width at posterior margin; length and breadth about equal. Median eyes of average size situated just forward of midpoint of carapace; width of median diad about one-fifth of width of carapace at that point (22/110). Surface polished in spite of numerous granules situated chiefly on dark pattern areas and seemingly coarser and more conspicuous than corresponding granules of boreus; carapace of male more coarsely granulate than that of females.
Preabdomen: With typical sculpturing of boreus.
Cauda: Similar to that of boreus (figs. 16, 17) on all surfaces. Obsolete inferior median keels of segments I-IV with 3-4-4-5 pairs of setae.
Telson: Essentially smooth: vesicle globular, somewhat less slender than that of boreus; sting gradually curved, half as long as vesicle.
Pectines: Pectinal teeth of female 18-22, of male 25-29.
Chelicerae: Similar in both sexes and differing little from those of boreus (figs. 46-48). Lower margin of fixed fingers usually with two distinct, dusky nodules at base. Lower margin of movable finger with keel dissected into four to seven distinct, irregularly formed teeth.
Pedipalps: Those of female of medium length, with heavy hands and fingers as shown in figure 28. Basal segments with all carinae coarsely granulated. Chelae greatly incrassated, with all eight carinae distinct as in boreus but somewhat smoother and less granulose. Inner keels of fingers rather smooth, weakly scalloped, and armed as in boreus. Pedipalp of male far more slender than that of female as shown in figure 27, with carinae rather weak and weakly granulated as compared with those of female.
Walking legs: With setation essentially as in boreus, but protarsi with fewer and quite irregularly spaced setae.

Williams (1980):

"DIAGNOSIS.-Dorsal surface of carapace and mesosoma with underlying dusky or dark markings, dusky markings continuous to posterior margin of each mesosomal tergum; position of ventromedian and ventrolateral keels of metasoma with underlying dusky or dark markings: base color of cuticle dull orange or yellow. Metasoma with ventrolateral keels weakly developed and smooth. ventromedian keels obsolete, position of ventromedian keels of segments 1-IV set with 3, 4, 4, 5 pairs of setae, respectively; chelicera with ventral margin of fixed finger usually with 2 distinct, dusky denticles at base; ventral margin of movable finger with about 4-7 irregular denticles; pectine teeth 18-22 in females, 25-29 in males.
Similar to P. arnaudi, but distinguished by obsolete ventromedian metasomal keels (not smooth to lightly crenulate)."

distribution: NORTH AMERICA. México (Baja California Norte), USA (southern California). View Map

published records:  Records: California: Modoc County: Adin Summit, September 18, 1961 (W. Ivie, W. J. Gertsch), one immature. El Dorado County: Ranger Station, 12 miles east of Kyburz, October 9, 1945 (G. Linsley, J. W. MacSwain, R. F. Smith), female. Marin County: Mt. Tamalpais, May 13, 1934, female. San Joaquin County: One and one-quarter miles east of Atomic Energy Commission Explosive Test Site, Corral Hollow Valley, July 31, 1965 (K. Hom), pit trap, two females. Contra Costa County: Four miles south of Antioch, April 9, 1945 (R. F. Smith), two males, six females; Antioch, sand dunes, March 16, 1951 (E. I. Schlinger), male. Alameda County: Corral Hollow, 5 miles west of Tracy; April 19, 1945 (R. F. Smith, 0. Bacon), two immature females, March 8, 1945 (R. F. Smith, A. E. Michelbacher), female. Corral Hollow, October 1, 1945 (J. W. MacSwain), female. Canyon north of Mitchell Ravine, August 26, 1965 (K. Hom), pit trap, male. Tuolumne County: Four miles west of Pinecrest, July 8 and 16, 1961 (J. Rozen), two males, female; Reservoir Canyon, San Luis Obispo, August 15, 1959 (V. Roth, W. J. Gertsch), male. San Benito County: Four miles east of Panoche, July 28, 1965 (K. Hom, V. Lee), female. Fresno County: Cedar Grove, Kings River Canyon, 4633 feet, July 16, 1952 (W. J. Gertsch), female. Monterey County: Indian Creek, King City-Memorial Park Road, January 16, 1956 (H. B. Leech), under stones, male. Junipera Serra Peak, 5800 feet, Santa Lucia Mountains, August 9, 1956 (L. Salanave), male, August 14, 1956 (B. Hargis), male, August 15-16, 1956 (H. B. Leech), under stones, male, two females; Seaside, behind beach dunes, June 24, 1957 (T. J. Cohn), female with boreus pattern; Cone Peak Trail, 4100-5100 feet, 3.5 air miles northeast of Lucia, August 18, 1957 (T. J. Cohn), male, four females. Tulare County: Near Ash Mountain, Sequoia National Park, July 9, 1958 (W. J. Gertsch, V. Roth), immature female. Ventura County: Wheeler Springs, July 2, 1958 (W. J. Gertsch, V. Roth), three immature females; 10 miles north of Wheeler Springs, July 2, 1958 (V. Roth), female; Mt. Pinos, July 31, 1961 (V. and B. Roth), male, two females. Los Angeles County: Los Angeles; July 30, 1948 (C. and P. Vaurie), immature female, March, 1922 (G. Grant), male, immature, November-December, 1912 (D. D. R. Ruthling), male; Lower Shake Camp, Pine Canyon, July 6, 1954 (W. A. McDonald), female; Crystal Lake, San Gabriel Mountains, September 29, 1965 (J. and W. Ivie), two females. Orange County: Santa Ana Canyon, 12 miles east of Capistrano, March 30, 1960 (W. J. Gertsch), male. Riverside County: Riverside, 500-800 feet, July 14, 1907, female; Keen Camp area, San Jacinto Mountains, April 26, 1961 (W. J. Gertsch), male. San Diego County: Mt. Palomar State Park, July 13, 1953 (W. J. and J. W. Gertsch), immature females; Del Mar, April 1, 1956 (J. A. Comstock), female; 6 miles northwest of Campo, on Hauser Creek, October 1, 1961 (W. J. Gertsch, W. Ivie, V. Roth), female, immature female. Baja California Norte: La Rumarosa; 43 miles west of Mexicali, October 7, 1961 (O. Clarke), female, October 1, 1961 (V. Roth), immature; 10-15 miles south of La Rumarosa, July 14, 1961 (V. Roth), female; Ensenada, March 10, 1946 (B. Malkin), immature female; 17 miles north of Colonia Guerrero, April 29, 1961 (W. J. Gertsch, V. Roth), male.
Baja California Norte, Mexico: 4.8 km S Mexicali-Tecate hwy.. Sierra Juarez, 20-VI-1973 (Williams. Blair); 16.6 km SW Rumorosa, 25-VII-1963 (LBS); El Progreso, head of El Tajo Canyon, 12-IX-1958 (Truxal, LACM); Sierra Juarez, Sawmill, 9-VII-I969 (Williams, Lee); Laguna Hanson, 7-X-1938 (Meadows, LACM); 18 km SE Ojos Negros, 15-VII-I969 (Williams. Lee): 19 km E Ensenada. 15-VI I- 1969 (Williams, Lee); NE slope N Los Coronados Islands, 20-VI-196I (Farmer); between Rancho Filipinas and Rancho Viejo, 30-VI-I962 (Lindsay); Punta Banda. 10-VII-1969 (Williams, Lee); Puerto Santo Tomas, ll-VII-1969 (Williams, Lee); 0.8 km W La Milla Ruins, Sierra Juarez, 21-VI-1973 (Williams, Blair); 2.6 km N Punta Calaveras, Hematite Mine. I3-VII-1962 (Parrish); Arroyo Seco. 9-II-1964 (Allen, Croulet); 26 km E Meling Ranch, Sierra San Pedro Martir. 13-VII-1969 (Williams. Lee); La Grulla. Sierra San Pedro Martir. 5-IX-1961 (Parrish, Lindsay, Sloan); Mike's Sky Ranch. Sierra San Pedro Martir. 14-19-VI-1973 (Williams, Blair); SW side La Encantada Meadow. Sierra San Pedro Martir, 5-IX-I961 (Parrish); 0.5 km SW Socorro, San Pedro Martir foothills, 2-IX-196I (Parrish); 8.0 km N Colonia Guerrero, 23-VIII-1961 (Parrish); El Progreso, l-IV-1969 (Williams). 

notes:  Beutelspacher (2000) lists a record of P. silvestrii from Sonora (Benjamin Hill); this record was based on a misidentified specimen of Vaejovis spinigerus (Wood). Williams (1980) stated,  "One of the most abundant scorpions in the higher elevations of the northern parts of the Baja California. It occupies a wide variety of ecological conditions, but is generally not found east of the Sierra Juarez and Sierra San Pedro Martir. Commonly encountered in coastal sand dunes, chaparral foothills, oak grassland,and coniferous forests."

Paruroctonus silvestrii (Borelli), male.  Photograph by W. David Sissom

Paruroctonus silvestrii (Borelli), male.  Photograph by Warren Savary


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