Pseudoscorpiones

Pseudogarypus bicornis, copyright Mark Harvey.

Belongs within: Arachnida.
Contains: Chthoniidae, Iocheirata.

The Pseudoscorpiones are a group of small arachnids, superficially resembling scorpions due to the possession of large chelate pedipalps but lacking the elongate metasoma or posterior sting of a scorpion.

Characters (from Muchmore 1990): Body divided between anterior prosoma (cephalothorax) and posterior opisthosoma (abdomen), with the two sections broadly connected. Dorsal surface of prosoma covered by single large carapace; one or two pairs of eyes often present laterally toward the front. Venter of prosoma covered by coxae of palps and legs. Chelicerae two-segmented, chelate, attached close together under anterior margin of carapace; several setae present on chelicera with cluster of setae on medial side forming flagellum; comblike or membranous serrula present along side of each finger; spinneret (galea) present near end of movable finger. Pedipalps six-segmented, chelate; trichobothria present on chela. Legs six- or seven-segmented; pretarsus bearing two claws and arolium. Opisthosoma with twelve tergites; usually only eleven visible sternites; eleventh tergite and sternite sometimes fused as circumanal ring; twelfth tergite and sternite each very small anal plate. Spiracles present at lateral edges of third and fourth sternites.

<==Pseudoscorpiones [Cheliferinea, Chelonethi, Epiocheirata, Homosphyronida, Monosphyronida]
    |--+--Chthoniidae MHG08
    |  `--Iocheirata MHG08
    `--Feaelloidea MHG08
         |--Feaella [Feaellidae] MHG08
         |    `--F. anderseni MHG08
         `--Pseudogarypidae MHG08
              |--Neopseudogarypus scutellatus MHG08
              `--Pseudogarypus MHG08
                   |--P. banksi M90
                   `--P. bicornis MHG08

Pseudoscorpiones incertae sedis:
  ‘Acarus’ scorpioides Linnaeus 1758 H02
  Opsochernes carbophilus FF99
  Thelassochernes pallipes FF99
  Paratemnoides nidificator Balzan 1888 WR08
  Ectoceras T89
    |--E. bidens T89
    `--E. helferi T89
  Megathis T89
    |--M. desiderata T89
    `--M. kochii T89
  Obisium T89
    |--O. pallipes Lucas 1846 E12
    `--O. trifidum T89
  Dracochela Schawaller, Shear & Bonamo 1991 H02
    `--D. deprehendor Schawaller, Shear & Bonamo 1991 H02

*Type species of generic name indicated

REFERENCES

[E12] Evenhuis, N. L. 2012. Publication and dating of the Exploration Scientifique de l'Algérie: Histoire Naturelle des Animaux Articulés (1846–1849) by Pierre Hippolyte Lucas. Zootaxa 3448: 1–61.

[FF99] Forster, R., & L. Forster. 1999. Spiders of New Zealand and their World-wide Kin. University of Otago Press: Dunedin (New Zealand).

[H02] Harvey, M. S. 2002. The neglected cousins: what do we know about the smaller arachnid orders? Journal of Arachnology 30 (2): 357–372.

[M90] Muchmore, W. B. 1990. Pseudoscorpionida. In: Dindal, D. L. (ed.) Soil Biology Guide pp. 503–527. John Wiley & Sones: New York.

[MHG08] Murienne, J., M. S. Harvey & G. Giribet. 2008. First molecular phylogeny of the major clades of Pseudoscorpiones (Arthropoda: Chelicerata). Molecular Phylogenetics and Evolution 49: 170–184.

[T89] Thorell, T. 1889. Viaggio di Leonardo Fea in Birmania e regioni vicine. XXI.—Aracnidi Artrogastri Birmani raccolti da L. Fea nel 1885–1887. Annali del Museo Civico di Storia Naturale di Genova, Serie 2a 7: 521–729.

[WR08] Walsh, R. E., & L. S. Rayor. 2008. Kin discrimination in the amblypygid, Damon diadema. Journal of Arachnology 36 (2): 336–343.