REVSYS: SYSTEMATICS OF THE
SCORPION FAMILY VAEJOVIDAE
HomeScorpionsVaejovidaeThe ProjectActivities/Products AcknowledgmentsLinks

 

What are vaejovids?

Family Vaejovidae
Genus Paravaejovis

Genus Paruroctonus
Genus Pseudouroctonus
Genus Serradigitus
Genus Smeringurus
Genus Syntropis
Genus Uroctonites
Genus Uroctonus
Genus Vaejovis
Genus Vejovoidus

Why study vaejovids?

Diversity
Endemism
Taxonomy
Phylogeny
Biogeography

Bibliography

Diversity


As recognized by our research team, the family Vaejovidae is the most speciose group of North American scorpions, and is comprised of 10 genera, 153 species, and 19 subspecies (Sissom 2000; Armas & Martín-Frías 2001; Capes 2001; Hendrixson 2001; Hendrixson & Sissom 2001; Baldazo 2003; González et al. 2004; Sissom & González 2004; Ponce & Sissom 2005).  By comparison, the remainder of the North American scorpion fauna consists of 12 genera and 85 species. However, knowledge of vaejovid diversity is still very limited.  We estimate that more than double the described species will be recognized once all habitats have been thoroughly surveyed (see Table 1 below).

A large number of undescribed species is predicted because vaejovids are substratum specialists and occupy restricted distributional ranges.  This combination of factors implies that α and β diversity of vaejovids should be greatest in regions of geological complexity (e.g. mountain ranges) and substratum heterogeneity (e.g. deserts), many of which remain poorly surveyed for scorpions.  At least 60 new species have already been identified in museum collections but many parts of North America, particularly mainland Mexico, are poorly sampled, if at all (Lourenço & Sissom 2000; Sissom & Hendrixson, 2005).  For example, recent fieldwork by W.D. Sissom confirms that inselbergs in Arizona and New Mexico alone harbor approximately 15 new species in the Vaejovis vorhiesi complex.  Extrapolating from sampled areas with high known diversity to poorly sampled areas, more species in the vorhiesi complex should be found in the Sierra Madre Occidental and nearby isolated desert mountain ranges in western Mexico, where the group is presently unknown but where there is abundant suitable habitat.  Numerous undescribed species are also expected in Pseudouroctonus, Serradigitus, Uroctonites, and the mexicanus and nitidulus groups of Vaejovis. In fact, with the exception of the Baja peninsula, Mexico remains very poorly sampled (Lourenço & Sissom 2000).  Current knowledge of scorpion diversity and distribution on the Mexican mainland is based largely on sporadic ‘rock-rolling’ by general collectors, a technique that is inefficient and delivers a sample strongly biased toward rupicolous species.  Many fossorial species, especially those occurring in sandy habitats, cannot be collected at all using this method. In contrast, nocturnal collecting with ultraviolet (UV) light detection (exploiting the fluorescence property of scorpion epicuticle) greatly increases yields and led to discovery of numerous undescribed species, even in areas previously thought to have been well-collected (Honetschlager 1965; Williams 1968, 1980; Stahnke 1972; Lamoral 1979 ; Sissom et al. 1990).  For example, UV detection on expeditions to the Baja peninsula by S.C. Williams in the 1960s resulted in the description of 35 new species (58.3% of the current fauna), more than doubling the number known at the time. In addition, the number of species recorded from the peninsula was tripled because many described species were reported for the first time.  The understanding of distributions for all species on the peninsula was also vastly improved.  Even with all of this intensive collecting, undescribed species remain in Baja California: a new species of Paruroctonus and at least two new species of Vaejovis were collected during the first collecting trip for the REVSYS project (link to field trips and scorpions).  Vaejovids constitute 83% of the Baja scorpion fauna (the figure for all of Mexico is about 70%).  There is no doubt that intensive collecting efforts, using UV detection throughout mainland Mexico will tremendously enhance our knowledge of the scorpion species diversity and geographical distributions there.  Indeed, the diversity in many states on the mainland may well approach that of Baja.

Table 1. Described and estimated number of infrageneric taxa in the Vaejovidae.  Letters denote genera and species groups as follows:  A = Paravaejovis; B = Paruroctonus; C = Pseudouroctonus; D = Serradigitus; E = Smeringurus; F = Syntropis; G = Uroctonites; H = Uroctonus; I = Vaejovis eusthenura group; J = V. intrepidus group; K = V. mexicanus group; L = V. nitidulus group; M = V. punctipalpi group; N = unplaced Vaejovis; O = Vejovoidus

Species

Genus or Species Group

Total

 

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

 

Described

1

29

13

24

4

1

4

3

17

3

20

16

9

8

1

153

Subspecies*

0

4

2

1

1

0

0

1

3

2

1

0

4

0

0

19

Known Undescribed

0

2

0

4

0

0

0

0

7

3

32

9

0

2

0

59

Estimated Undescribed

0

5

10

11

0

0

0

0

7

4

20

10

0

6

0

70

Total

1

40

25

40

5

1

4

4

34

12

73

35

13

13

1

301

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

*Excluding nominotypical subspecies.

Literature Cited: 

Armas, L.F. de & Martín-Frías, E. 2001. Dos nuevos Vaejovis (Scorpiones: Vaejovidae) de Guerrero y Nayarit, México. Solenodon 1: 8–16.

Baldazo-Monsivais, J. G.  2003.  Vaejovis zihuatanejensis, nueva especie de la alacrán del Estado de Guerrero, Mexico (Scorpiones:  Vaejovidae).  Entomología Mexicana 2: 6772.

Capes, E.M. 2001. Description of a new species in the nitidulus group of the genus Vaejovis (Scorpiones, Vaejovidae). Journal of Arachnology 29: 42–46.

González Santillán, E., Sissom, W.D. & Pérez, T.M. 2004. Description of the male of Vaejovis sprousei Sissom, 1990 (Scorpiones: Vaejovidae). Texas Memorial Museum, Speleological Monographs 6: 9–12.

Hendrixson, B.E. 2001. A new species of Vaejovis (Scorpiones, Vaejovidae) from Sonora, Mexico. Journal of Arachnology 29: 47–55.

Hendrixson, B.E. & Sissom, W.D. 2001. Descriptions of two new species of Vaejovis C. L. Koch, 1836 from Mexico, with a redescription of Vaejovis pusillus Pocock, 1898 (Scorpiones: Vaejovidae). In: Fet, V. & Selden, P.A. (Eds.) Scorpions 2001. In Memoriam Gary A. Polis. British Arachnological Society, Burnham Beeches, Bucks, 215–223.

Honetschlager, L.D. 1965. A new method for hunting scorpions. Turtox News 43: 69–70.

Lamoral, B.H. 1979. The scorpions of Namibia (Arachnida: Scorpionida). Annals of the Natal Museum 23: 497–784.

Lourenço, W.R. & Sissom, W.D. 2000. Scorpiones. In: Bousquets, J.L., González Soriano, E. & Papavero, N. (Eds.) Biodiversidad, Taxonomía y Biogeographía de Artrópodos de México: Hacia una Síntesis de su Concimiento. Volume II. Universidad Nacional Autónoma de México, Ciudad de México, 115–135.

Ponce Saavedra, J. & Sissom, W.D.  2004.  A new species of the genus Vaejovis (Scorpiones, Vaejovidae) endemic to the Balsas Basin of Michoacan, Mexico.  Journal of Arachnology 32: 539–544.

Sissom, W.D. 2000. Family Vaejovidae. In: Fet, V., Sissom, W.D., Lowe, G. & Braunwalder, M.E. Catalog of the Scorpions of the World (1758–1998). The New York Entomological Society, New York, 503–553.

Sissom, W.D. & González Santillán, E. 2004. A new species and new records for the Vaejovis nitidulus group, with a key to the Mexican species (Scorpiones, Vaejovidae). Texas Memorial Museum, Speleological Monographs 6: 1–8.

Sissom, W.D. & Hendrixson, B.E. 2005. Scorpion biodiversity and patterns of endemism in northern Mexico. In: Cartron, J.-L.E. & Ceballos, G. (Eds.) Biodiversity, Ecosystems, and Conservation in northern Mexico. Oxford University Press, Oxford, UK, 122–137.

Sissom, W.D., Polis, G.A. & Watt, D.D. 1990. Field and Laboratory Methods. In: Polis, G.A. (Ed.) The Biology of Scorpions. Stanford University Press, Stanford, CA, 445–461.

Stahnke, H.L. 1972. UV light, a useful field tool. BioScience 22: 604–607.

Williams, S.C. 1968. Methods of sampling scorpion populations. Proceedings of the California Academy of Sciences (4) 36: 221230.

Williams, S.C. 1980. Scorpions of Baja California, Mexico, and adjacent islands. Occasional Papers of the Califorinia Academy of Sciences 135: 1–127.

 


The material included in this site is based upon work supported by the National Science Foundation under Grant No. 0413453.  Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.
THE UNAUTHORIZED COPYING, DISPLAYING OR OTHER USE OF PHOTOGRAPHS OR OTHER CONTENT  FROM THIS SITE IS A ILLLEGAL. 
© Copyright 2005-2006.  All images in this site, even if they do not include an individual statement of copyright, are protected under the U. S. Copyright Act.  They may not be "borrowed" or otherwise used without our express permission or the express permission of the photographer(s),  artist(s), or author(s).  For permission, please submit your request to wsavary@yahoo.com.