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zomids their absence is considered to be plesiomorphic.Cheliceral brush (character 16): The Hubbardiidaehave a brush of setae (type 5) on the base of thefixed cheliceral digit. The plesiomorphic conditionof no brush is known in the Protoschizomidae andUropygi.Mesal setation of the chelicerae: We have recordedthe number of setae for each species of Protoschizomidae,but intraspecific variation in thischaracter makes it of limited value.The anterior process of the propeltidium is downturnedin most Hubbardiidae and Protoschizomidae.The straight forward-pointing process in A. patei isconsidered to be an autapomorphy.Within the order, several patterns have been observedin the setation on the anterior process of thepropeltidium. As already noted the presence of thesesetae is a synapomorphy for the order. In the Protoschizomidaethere is either one or a row of two setaeon the process. Protoschizomus (Fig. Ib) sharesa row of two setae with all New World Hubbardiidae,with the exception of species of Hubbardia. InHubbardia, Megaschizomus, Trithyreus, and mostOld World species assigned (most incorrectly) toSchizomus the anterior process bears a pair of setaefollowed by a single seta. The presence of a row oftwo setae in Protoschizomus and Hubbardiidae impliesthat this is the plesiomorphic condition in theprotoschizomids. Agastoschizomus lost one seta(character 17).Pair of setae at base of process (character 18): Inthe Protoschizomidae there is a pair of setae at thebase of the anterior process of the propeltidium.This pair is absent from the Hubbardiidae andUropygi.Setae on anterolateral margin of propeltidium:Megaschizominae have six or seven setae, in additionto the setae on and at the base of the anteriorprocess, on the anterior margin of the propeltidium.All other Schizomida and Uropygi lack setae in thisregion.The number of dorsal setae and placement on thepropeltidium varies somewhat intraspecifically, butspecies of the P. pachypalpus group all have threeor four pair, whereas other protoschizomid specieshave one or two pair. Members of Hubbardiidaehave two to five pair. In the Protoschizomidaewhere the lower number of pairs occurs it is the posteriormostpairs that are absent, whereas in speciesof Hubbardiidae with two pair, the middle pairs areabsent. Because different setal pairs appear to havebeen lost, we suggest the plesiomorphic conditionfor the order is more than two pairs (character 19).Further support for this polarity assignment is thewidespread occurrence of this condition in the order.Eyes: The Protoschizomidae and Megaschizominaelack eyespots. The Hubbardiidae usually havedistinct eyespots, but these are sometimes absent,most frequently in cavernicolous species. A fewspecies of Old World Hubbardiidae have distinctfaceted lateral eyes. Lateral eyes are present in otherArachnidea indicating this is a plesiomorphic condition.However, the widespread loss of eyes in theSchizomida suggest that the presence of lateral eyespotsand eye facets is a reversal or a new structure.The apomorphic interpretation of the eyespots iscorrelated with other characters in the Hubbardiidaeknown to be apomorphic.Posterodorsal abdominal process: Some speciesof Hubbardiinae have a distinctly developed processat the posterior margin of abdominal segment XII.The absence of this process in the Protoschizomidae,Megaschizominae, and many species of Hubbardiidaeimplies that absence is the plesiomorphic condition.Pedipalps: The shape of the pedipalp is useful inspecies recognition. In the Hubbardiidae the pedipalpmay be highly modified both in shape and armatureand appears of use in constructing phylogenies.Unlike many species of Hubbardiidae andUropygi, the male and female pedipalps in the Protoschizomidaeare essentially the same shape andpossess the same armature (character 20). However,the male pedipalp is distinctly longer than the femalepedipalp in relation to body length in the P. pachypalpusgroup. This condition is considered to be areversal in the Protoschizomidae (character 21). Theincrease in size of the spurs and claw in the Protoschizomidaeis generally correlated with bodysize. The claw is greatest in A. patei and almost aslarge in other species of Agastoschizomus. These arealso the most troglomorphic species and this isprobably an adaptation to cave life and possibly correlatedwith a more active hunting strategy of thecavernicole in a food poor environment. Large clawsalso occur in Megaschizominae and Trithyreus, bothwith large species.Pedipalp trochanter produced distally: The distalmargin of the trochanter of the pedipalp in mostspecies of Protoschizomidae is not produced; it isslightly produced in P. sprousei and P. purificacion.It is distinctly produced in Megaschizominae. In theHubbardiinae it may not be produced or may behighly produced and bear spurs or spinose-setae onthe distal margin. The pedipalps ofjuveniles are notproduced, implying that this is the plesiomorphiccondition. The slightly produced trochanter in some37