On the consistency of some taxonomic characters in the Scolopendromorpha and comments on the scolopocryptopid subfamily Kethopinae (Myriapoda: Chilopoda)

With the increase in taxonomic data it has become apparent that some characters are less reliable as phylogenetic and taxonomic characters in the Scolopendromorpha than previously thought. Examples of this are considered. The problematic scolopocryptopid subfamily Kethopinae is discussed. New World species of Scolopendra Linnaeus, 1758 plus the Old World species S. valida Lucas, 1840 are a monophyletic group, usually with an anterior transverse sulcus (ring furrow) on T1. A subgroup of ten species have 17 antennal articles, and dorsodistal prefemoral spines on legs anterior to the ultimate pair. A second subgroup of six species have more than 17 antennal articles and lack the dorsodistal prefemoral spines on legs anterior to the ultimate pair. Exceptions are discussed. S. valida fits into neither group. Some Cryptops (Trigonocryptops) Verhoeff, 1906 lack the otherwise characteristic sternite trigonal sutures and C. (Cryptops) anomalans Newport, 1844 shows some of the morphological characters used to characterise Trigonocryptops Verhoeff, 1906. The rather incomplete data for Kethops utahensis (Chamberlin, 1909) (Scolopocryptopidae, Kethopinae) and the description of Thalkethops grallatrix Crabill, 1960 suggests that they are characterised by ultimate legs with rows of saw teeth on the prefemur, femur and tibia, with a single saw tooth on tarsus 1. This is not the case, however, in K. atypus Chamberlin, 1943 which shows characters typical of many Cryptops species and may be a Cryptops with 23 leg-bearing segments. The reason why some important characters may be overlooked is discussed.