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of ovipositor sections presented in that study, it ispossible to conclude that the hyperexpanded segmentis actually the everted vagina (ibid, figs. 30-33) andthat the openings to the seminal receptacles are to befound at the bases of the apical lobes.Sexual dimorphisms.-The most conspicuoussexual dimorphism is the male trochanteral spur, alarge, robust process located ventroapically on thefourth trochanter (Figs. 24, 25). In several speciesthis structure is reduced in size (Figs. 91, 192), inonly one (T. mulaiki) it is completely absent (Fig.104), and in another (T. bifurcata) it is representedby one to three small, rounded tubercles (Fig. 11).(The female homolog of the spur is represented byone to two small tubercles, for example in Fig. 17.)Similar, although smaller, trochanteral spurs arepresent in some species of Sitalcina and the EuropeanScotolemon Lucas.The second conspicuous dimorphic structure, thepostopercular process (POP), appears to be uniqueto Texella. The POP is a conical cuticularoutgrowth located immediately behind the genitaloperculum and is found in most members of themulaiki species group (Figs. 132, 133). Thereappears to be no female counterpart to this unusualstructure [although one aberrant female of T. reyesidoes possess both a vestigial POP and spur (Figs.130, 134, 135)).Another interesting dimorphism is found in thefemales of the spinoperca infragroup. In thesespecies the genital operculum is modified apically;bearing 1-2 pairs of short spines (Figs. 171, 173,182, 183, 194). Males lack these spines, except forT. spinoperca where some males have homologsrepresented by short, blunt tubercles (Fig. 181).Similar apical tubercles are found in both sexes of T.jungi and shoshone (Figs. 64, 71).Finally, in one species, T. jungi, the number ofparaocular AT appears to be sexually dimorphic:males have 6-7 pairs, females 2-3 pairs (Figs.60-62).Somatic characters.-The somatic charactersused in the analysis were: the number and arrangementof anterior tubercles, the tarsal count, and thenumber of palpal megaspines. Most of these andother somatic characters are discussed in the sectionon Troglomorphy.PHYLOGENYThe character numbers in the following discussioncorrespond to those listed in Table 1.SISTER GROUPI) Ventral plate (VP) bifurcation. Three cladesof Nearctic harvestmen have deeply bifurcate ventralplates: Phalangodes and the nominal genera of theAppalachian region [henceforth referred to as Phalangodes(et al.); Briggs, 1974: fig. 7], Banksula(Fig. 5), and Texella (Figs. 6, 7). In the remaininggenera, which includes Calicina, the probable plesiomorphicsister of all Nearctic Phalangodidae, theVP is entire, suggesting that a bifurcate VP isderived.We are not sufficiently familiar with the Europeanphalangodids, the probable closest relatives of theNearctic fauna, to fully include them in the discussion.However, we have examined specimensand/or published illustrations of representatives ofall Mediterranean genera, with the exception of LolaKratochvil and Paralola Kratochvil, and none has abifurcate VP. However, an apically notched VPoccurs in some (but not all) species of Scotolemon(doriae, Martens, 1978, and terricola, Brignoli,1968) and Ausobskya (athos, Martens 1972). Thenotch is only about 1,4 the length of the VP and is,therefore, quite distinct from the bifurcate conditionin the Nearctic genera. Even assuming homology,the notch appears to be plesiomorphic relative to thebifurcation and so would not alter the monophyly ofthe Nearctic clade.2) Apical spine (AS). The AS appears to bepresent only in, and is considered a synapomorphyfor, Banksula and Texella (Figs. 5-7).3) Ventral plate prong (VPP) position. InBanksula the VPP are located ventrally, as is the VPof other Californian genera, suggesting that thelateral position of the VPP in Texella and Phalangodes(et al.) is derived.The sister group of Texella cannot be establishedwith much certainty at this time. However, takinginto consideration the relative merit of characters 2and 3, the shared presence of a unique structure(AS) appears to offer the stronger argument in supportof a sister relationship with Banksula. Additionalcharacters will obviously be necessary to resolvethis issue. On the other hand, there seems littledoubt that, of the three clades, Banksula is themost plesiomorphic. In addition to the placement ofthe VPP, several other character states of Banksulaare best interpreted as plesiomorphies: VP bifurcationnarrow; AS short, apically unmodified;VP setae short and slender; glans folding simple;glans with few accessory structures; and glans basalsegment small. By contrast, Phalangodes (et al.) isclearly and strongly derived. For example, the VPP160