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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?



Family Vaejovidae Thorell 1876

[Currently under revision]

Distribution. - North America: Canada (Alberta, British Columbia), U.S.A. (Alabama, Arizona, California, Colorado, Georgia, Idaho, Kentucky, Mississippi, Montana, Nebraska, Nevada, New Mexico, North Carolina, North Dakota, Oregon, South Carolina, Tennessee, Texas, Utah, Washington, Wyoming), Mexico (all states), Guatemala

Synonymy and Literature:  [In preparation]

Remarks.  Historically, family Vaejovidae included a diverse assemblage of taxa from around the world. As originally construed by Thorell (1876), Vaejovidae included only the genera Vaejovis and Hadrurus. Iurus and Uroctonus were placed in subfamily Iurinae of Pandinoidae. Pocock (1893) placed all four genera, along with Scorpiops, Anuroctonus, Caraboctonus and Hadruroides, in subfamily Iurini of family Iuridae. The entire assemblage was elevated to family Vaejovidae by Laurie (1896a,b) and divided into two subfamilies―Iurini (Iurus, Uroctonus, and Caraboctonus) and Vejovini (Scorpiops, Vejovis, Anuroctonus, Hadrurus, and Hadruroides). The name Vejovidae was reapplied for this family by Kraepelin (1905), who added Syntropis and recognized five subfamilies: Syntropinae (Syntropis), Vejovinae (the Nearctic Vejovis, Uroctonus, Anuroctonus, and Hadrurus), Caraboctoninae (the South American Caraboctonus and Hadruroides), Iurinae (the Eurasian Iurus), and Scorpiopsinae (Scorpiops from southern Asia). This basic arrangement persisted into recent times, with genera added to subfamilies as authors thought appropriate. Stahnke (1974) separated Hadrurus and Anuroctonus into a separate subfamily, Hadrurinae.

The first major change in this scheme was the recognition of Iuridae as distinct from Vaejovidae, by removal of Iurus, Calchas, Hadrurus, Hadruroides and Caraboctonus from the latter (Francke & Soleglad 1981). Although Anuroctonus was excluded from Iuridae by Francke & Soleglad (1981), Stockwell (1992) returned it to that family, following Stahnke (1974). Two further modifications occurred before the interpretation of Vaejovidae portrayed by Stockwell (1989, 1992) and Sissom (2000), and adopted by this research group, was achieved. First, Francke (1976) suggested that Scorpiopsinae (now including Dasyscorpiops, Euscorpiops, Neoscorpiops, Parascorpiops, and Scorpiops, all placed in Euscorpiidae) should be removed from Vaejovidae, but made no formal changes. The transfer was officially made by Stockwell (1992) on the basis of cladistic evidence for a closer relationship to other chactoid families (Stockwell 1989), a move that was endorsed by Soleglad & Sissom (2001), who presented a more detailed phylogenetic analysis of the internal relationships of the redefined Euscorpiidae. Second, Nullibrotheas, regarded as a vaejovid by Williams (1974, 1980), was transferred to the Chactidae (Stockwell 1989, 1992).           

In the most recent development, Soleglad & Fet (2003, 2004), as part of an analysis of the phylogenetic relationships of extant scorpions, transferred Uroctonus from Vaejovidae to Chactidae. Soleglad & Fet (2003, 2004) resurrected the subfamily Uroctoninae to accommodate Uroctonus and also Anuroctonus, which they transferred from Iuridae, in turn redefining Iuridae to include only Calchas and Iurus, while creating another family, Caraboctonidae, to accommodate Caraboctonus, Hadruroides and Hadrurus. We reject subfamily Uroctoninae sensu Soleglad & Fet (2003, 2004) and the transferal of Uroctonus from Vaejovidae to Chactidae for the following reasons. The methods used in the phylogenetic analysis presented by these authors have been discredited and their resultant classification rejected (Prendini & Wheeler 2005). Uroctonus and Anuroctonus were artificially forced to be monophyletic in Soleglad & Fet抯 (2003) analysis by the inclusion of false synapomorphies (e.g. 𔃒 lateral ocelli) and the omission of characters that might support alternative hypotheses. These taxa are not sister taxa, let alone closely related based on phylogenetic analyses by others (e.g. Stockwell 1989) and work in progress, where characters supporting alternative hypotheses have also been included. The transferal of Uroctonus from Vaejovidae to Chactidae renders both families paraphyletic.

As recognised by our research group, Vaejovidae is restricted to North American taxa and includes 10 genera, 157 species, and 19 subspecies (Sissom 2000; Armas & Mart韓-Fr韆s 2001; Capes 2001; Francke & Gonz醠ez, in press; Francke & Ponce, in press; Francke & Savary, in press; Hendrixson 2001; Hendrixson & Sissom 2001; Baldazo-Monsivais 2003; Sissom & Gonz醠ez 2004; Ponce & Sissom 2005). The family is supported by at least two morphological synapomorphies (Stockwell 1989, 1992): the presence of a longitudinal carina on the inner face of the pedipalp patella (absent in a number of species) and a pouch-like invaginated sperm duct on the hemispermatophore. A search for additional synapomorphies is needed. No subfamilies or tribes are currently recognized, primarily because phylogenetic relationships among the genera remain to be resolved. In the only cladistic analysis of the internal phylogenetic relationships of Vaejovidae thus far presented, Stockwell (1989) obtained limited resolution among the genera, probably because his analysis was based on supraspecific terminal taxa, representing genera the monophyly of which was assumed (Prendini 2000, 2001). As in other scorpion families, many vaejovid genera are defined on the basis of plesiomorphic similarity and their monophyly remains untested. It is widely agreed that Vaejovis is polyphyletic and, according to Stockwell抯 analysis, the V. mexicanus group is basal to other vaejovids whereas the V. nitidulus group forms a central polytomy with three larger monophyletic groups, one of which includes the V. eusthenura and V. punctipalpi groups.

Literature Cited:

Armas, L.F. de & Mart韓-Fr韆s, E. 2001. Dos nuevos Vaejovis (Scorpiones: Vaejovidae) de Guerrero y Nayarit, M閤ico. Solenodon 1: 816.

Baldazo-Monsivais, J. G.  2003.  Vaejovis zihuatanejensis, nueva especie de la alacr醤 del Estado de Guerrero, Mexico (Scorpiones:  Vaejovidae).  Entomolog韆 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: 4246.

Francke, O.F. & Soleglad, M.E. 1981. The family Iuridae Thorell (Arachnida, Scorpiones). Journal of Arachnology 9: 233258.

Francke, O.F. 1976. Redescription of Parascorpiops montana Banks (Scorpionida, Vaejovidae). Entomological News 87: 7585.

Francke, O.F. and Gonz醠ez Santill醤, E. 2006. A new Vaejovis of the punctipalpi group from Guerrero. J. Arachnol. (in press).

Francke, O.F. and Ponce Saavedra, J. 2006. A new Vaejovis (Scorpiones: Vaejovidae) with a subaculear spine from Michoacan, Mexico. Rev. Iber. Aracnol. (in press).

Francke, O.F. and Savary, W.E. 2006. A new troglobitic Pseudouroctonus Stahnke (Scorpiones: Vaejovidae) from northern M閤ico. Zootaxa (in press).

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, 215223.

Hendrixson, B.E. 2001. A new species of Vaejovis (Scorpiones, Vaejovidae) from Sonora, Mexico. Journal of Arachnology 29: 4755.

Kraepelin, K. 1905. Die geographische Verbreitung der Skorpione. Zoologische Jahrb點her, Abteilung f黵 Systematik 22: 321364.

Laurie, M. 1896a. Notes on the anatomy of some scorpions, and its bearing on the classification of the Order. Annals and Magazine of Natural History (6) 17: 185194.

Laurie, M. 1896b. Further notes on the anatomy and development of scorpions, and their bearing on the classification of the Order. Annals and Magazine of Natural History (6) 18: 121133.

Pocock, R.I. 1893. Notes on the classification of scorpions, followed by some observations on synonymy, with descriptions of new genera and species. Annals and Magazine of Natural History (6) 12: 303330.

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: 539544.

Prendini, L. & Wheeler, W.C. 2005. Scorpion higher phylogeny and classification, taxonomic anarchy, and standards for peer review in online publishing. Cladistics 21: 446494.

Prendini, L. 2000. Phylogeny and classification of the Superfamily Scorpionoidea Latreille 1802 (Chelicerata, Scorpiones): An exemplar approach. Cladistics 16: 178.

Prendini, L. 2001. Species or supraspecific taxa as terminals in cladistic analysis? Groundplans versus exemplars revisited. Systematic Biology 50: 290300.

Sissom, W.D. 2000. Family Vaejovidae. In: Fet, V., Sissom, W.D., Lowe, G. & Braunwalder, M.E. Catalog of the Scorpions of the World (17581998). The New York Entomological Society, New York, 503553.

Sissom, W.D. & Gonz醠ez Santill醤, 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: 18.

Soleglad, M.E. & Fet, V. 2003. High-level systematics and phylogeny of the extant scorpions (Scorpiones: Orthosterni). Euscorpius 11: 1175.

Soleglad, M.E. & Fet, V. 2004. The systematics of the scorpion subfamily Uroctoninae (Scorpiones: Chactidae). Revista Ib閞ica de Aracnolog韆 10: 81128.

Soleglad, M.E. & Sissom, W.D. 2001. Phylogeny of the family Euscorpiidae Laurie, 1896: A major revision. In: Fet, V. & Selden, P.A. (Eds.) Scorpions 2001. In Memoriam Gary A. Polis. British Arachnological Society, Burnham Beeches, Buckinghamshire, UK, 25111.

Stahnke, H.L. 1974. Revision and keys to the higher categories of Vejovidae. Journal of Arachnology 1: 107141.

Stockwell, S.A. 1989. Revision of the phylogeny and higher classification of scorpions (Chelicerata). Ph.D. Dissertation, University of California, Berkeley.

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: 407422.

Thorell, T. 1876. On the classification of scorpions. Annals and Magazine of Natural History (4) 17: 115.

Williams, S.C. 1974. A new genus of North American scorpions with a key to the North American genera of Vaejovidae. Proceedings of the California Academy of Sciences (4) 40: 116.

Williams, S.C. 1980. Scorpions of Baja California, Mexico, and adjacent islands. Occasional Papers of the Califorinia Academy of Sciences 135: 1127.


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