The Taxonomy of the False Scorpion Genus Synsphyronus with Remarks on the Sporadic Loss of Stability in Generally Constant Morphological Characters (Arachnida: Chelonethida)

Abstract

The genus Synsphyronus Chamberlin was erected in 1930 (Ann. and Mag. Nat. Hist. (10), 5 : 609, 616–617) to accommodate an unusual species of the family Garypidae which differed primarily from other members of the group in having the metatarsus and tarsus of the legs secondarily fused to form a typical miotarsus. At the time, it was pointed out that, in spite of this unusual character, the genus was undoubtedly truly referable to the family Garypidae on the basis of every other morphological character definitive of that group. In spite of this, Beier in 1932 (Das Tierreich, 57 :238) elevated the genus to family rank (Synsphyronidae) and removed it from the superfamily Garypoidea[2][1] to the Feaelloidea. Consideration of the following tabular summary of the normal characteristics of these two superfamilies will clearly reveal the untenability of Beier's disposition of this genus. In every character but the invariable presence of a normal, two-segmented tarsus, Synsphyronus agrees with the characters itemized under the heading Garypoidea. [1]: #fn-1