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pairs) are found in six species: T. kokoweef (Fig.22), brevistyla (Fig. 48), T. jungi (males only, Fig.62), welbourni, reddelli (Figs. 118, 119; althoughsome individuals have only 4 pairs), and diplospina(Fig. 166). The wide distribution, across the entirecladogram, of the multituberculate state suggestsplesiomorphy. This in tum suggests that the highestnumber of AT represents the most plesiomorphiccondition.12) AT rows. A biserial arrangement of AT isfound in species with high numbers of AT (~ 5pairs). Outgroup comparison cannot be used withBanksula or Phalangodes (et al.) where the AT areabsent (or represented by 1-2 tiny tubercles). However,the 6-8 pairs of AT present in Calicina mariposaare arranged in a single row. This suggeststhat the biserial arrangement is a synapomorphy forTexella. Within Texella, the loss of the biserialcondition would be derived.13) Secondary parastylar lobes (PSL2). ThePSL2 are found only in the bifurcata and kokoweefgroups and because of their uniqueness may be consideredto be synapomorpic for them. However,there appears to be some evidence which suggeststhat the PSL2 are plesiomorphic within Texella.First, there is a trend of reduction of the PSL2 in thekokoweef group, the largest PSL2 being found in T.kokoweef (Fig. 15) and the smallest in deserticola,where they appear to be reduced to mere vestiges(Fig. 45). Also, in virtually all species of Texellathe lateral faces of the middle segment bear ratherprominent folds (for example Figs. 53, 96, 106,136, 163, 177, 181, 187). It seems at least possiblethat these folds represent vestigial PSL2. If this isthe case, the PSL2 would most parsimoniously beinterpreted as a synapomorphy for the entire genus(and the loss of prominent PSL2 as another synapomorphyfor the mulaiki group).The several characters discussed above suggest aunique position of T. bifurcata and the likelihoodthat this species represents the plesiomorphic sistergroup of the remaining Texella.The kokoweefgroup14) PSL2 direction. In T. bifurcata, the PSL2point along the mesal axis of the glans (towards theventral surface of the stylus; Fig. 15); in the kokoweefgroup the PSL2 point along the longitudinalaxis (towards the tip of the stylus; Fig. 27, 41, 45).Using T. bifurcata as the outgroup, the longitudinalalignment is taken to be a synapomorphy for thekokoweef group.The mulaiki group15) Postopercular process (POP). The POP isabsent in the bifurcata and kokoweef species groupsbut is found in virtually all members of the T. mulaikigroup, for which it is considered a synapomorphy.In some species (of the mulaiki and spinopercainfragroups) the POP is absent (Fig. 104) and inothers (of the brevistyla subgroup and of the reddelliand mulaiki infragroups) it may be reduced in size(Figs. 50, 92). This structure also exhibits variabledevelopment intraspecifically. In the species withthe largest available series, T. reyesi, the POP mayvary from being extremely large to small (Fig. 132,133), even within a single cave population, and(along with the trochanteral spur) appears to varyallometrically.16) Basal fold of stylus (BF). The BF is foundonly in members of the T. mulaiki species group(Figs. 53, 68, 77, 83, 87, 96, 107, 116, 120, 136,161, 164, 169, 177, 181, 187, 201), where it isconsidered to be derived.17) Basal knob (BK). The BK is absent inBanksula and the T. bifurcata and kokoweef speciesgroups and is, therefore, a synapomorphy for the T.mulaiki species group (Figs. 66, 77, 83, 86, 95,107, 114, 121, 136, 161, 163). Its absence from T.brevistyla (Fig. 76) and the T. spinoperca infragroup(Figs. 174, 180, 188, 198) is regarded as asecondary loss.The brevistyla and mulaiki subgroups18) Stylus length. In the T. bifurcata andkokoweef species groups (except in T. deserticola )and most species of Banksula the stylus is subequalin length to the PSL. Thus, both a longer stylus (asin T. deserticola (Fig. 45) and the mulaiki subgroup(Figs. 77, 83, 96, 107, 138, 161, 163, 168, 175,180) and an extremely short one [in the brevistylasubgroup (Figs. 53, 75) and in T. homi (Fig. 201)]can be considered derived.19) Tarsal count (TC). The lowest TC, 3-5-4-5,is found in all members of the bifurcata and kokoweefgroups and the brevistyla subgroup. A TC of3-5-5-5 or more is found in all remaining species(except T. bi/obata and homi). Given the presenceof additional plesiomorphies in the former group,the higher tarsal count is presumed to be derived.However, an increased TC is clearly a troglomorphiccharacter, best demonstrated by the clinal variationin the reddelli infragroup which is discussed163