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in the cuticle. As already mentioned in the methodssection, we consider segments to be subdivisionsseparated by breaks in the cuticle and subdivisionsseparated by a thinning of the cuticle as articles.This results in the use of opposite terms used bymost previous authors. They apparently did not examinethese annuli with sufficient magnification.Segments occur in all major groups of schizomids,whereas articles are apparently found only inMegaschizominae and Protoschizomidae. The lossof articles in the Hubbardiinae is considered a synapomorphy(character 30). The complete absence ofall annuli in A. patei is an autapomorphy. While thereverse (development of articles is a synapomorphyfor Megaschizominae and Protoschizomidae) is moreparsimonious, not requiring a reversal, it is notconsistent with other characters considered to beapomorphic. Treating the absence of articles asapomorphic resulted in a longer tree length (55rather than 54) when examined using Hennig86.The maximal number of annuli (five) occurs inthe Megaschizominae. Lawrence (1958) reportedthat the female flagellum of Megaschizomus consistedof three segments, but his illustration(redrawn in Fig. lc) showed annuli at five positions.From his description it appears he considered annuliat positions 4 and 5 to be true segmental divisions.Our examination of a female Megaschizomus suggestsjust the opposite; positions 1-3 are segmentaldivisions and positions 4 and 5 are only zones ofthinned cuticle. The flagellum we examined was incomplete,missing the latter two positions. When wetried to position the specimen for examination, thebasal segments broke apart cleanly, indicating thatthey were indeed segmental junctions. As alreadynoted, no true articles are recorded for the Hubbardiinae.The number of subdivisions in the Protoschizomidaeranges from 0-5.An annulus (segmental break) in position I isconsidered plesiomorphic as it occurs in both theHubbardiidae and Protoschizomidae. The loss ofthis annulus in A. srygius is an autapomorphy. Anannulus (segmental break) occurs at position 2 inonly members of the Hubbardiidae (both Megaschizominaeand Hubbardiinae). This annulus was apparentlysecondarily lost in some Hubbardiinae(character 31). An annulus at position 3 (segmentalbreak) is known from all family level groups ofschizomids. As it is also missing from numerous unrelatedtaxa in the Hubbardiinae and Protoschizomidaepresence/absence of an annulus at position 3 willlikely be useful only in separating congeneric species.An annulus at position 3 is found in A. lucifer,P. pachypalpus, P. purificacion, P. rowlandi, andP. sprousei. An annulus (thinning in cuticle inMegaschizominae and Protoschizomidae) is presentat position 4 in both families of schizomids and itsabsence in some Hubbardiinae is considered to be areversal. An annulus (thinning of the cuticle) ispresent at position 5 in the Megaschizominae andProtoschizomidae. It is apparently absent from theHubbardiinae and P. gertschi and is therefore consideredto have been lost on at least two occasions.As noted by Harvey (in press), the flagellar setationof the Hubbardiidae appears to be unique.While the same setae are present in the Hubbardiinaeas are present in the Megaschizominae and Protoschizomidae,the absence of setae resulting in thepattern dml, dm4, dB, vml, vrn2, vm4, vIl, vmS,vl2 is a synapomorphy for the Hubbardiinae.Harvey also noted that male and female flagella havethe same number of setae and that the setae occur atapproximately the same positions in the Hubbardiinae.This is not the case in the Protoschizomidaeand is considered to be a derived state (character32). Among female protoschizomids, drn2 is lackingfrom all species except P. gertschi and A. srygius(character 33). Because these species are apparentlyunrelated (based on other characters) and becausedrn2 do not occur in the Hubbardiidae, we suggestthese setae developed independently. Seta drn2 isalso lacking in penultimate males of P. sprousei andP. purificacion as well as adult males of P.sprousei, P. pachypalpus, P. rowlandi, and P. occidentalis(character 34). Several other setae areknown to be absent from male protoschizomid flagella:vm4 from P. pachypalpus and P. rowlandi(character 35); drn3 from A. patei; vmS from A.huitzmolotitlensis [note that vmS may also be missingfrom male A. patei - we have not labeled it inour drawing but suggest it is one of the off- centeredpairs numbered dl2, the second dl2 seta being absent(aberrant individual). Discovery of additional maleA. patei should resolve this matter.]. Only femalesof P. sprousei and P. purificacion lack dm4(character 36).Male flagellum: The male flagellum of protoschizomidsprovides the best characters for distinguishingspecies. It also appears to be useful in delineatinggeneric limits. In Protoschizomus the flagellumis distinctly enlarged distally (character 37), whereasin Agastoschizomus it does not increase in width distally.Since most species of Hubbardiidae also haveapically enlarged flagella it is likely that this is theplesiomorphic state.The male flagellum of protoschizomids (exceptA. patei) and Megaschizominae has soft, sometimeseversible areas. The males with these soft areas also40