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Texella). This is found in the three most troglomorphicspecies, the mulaiki infragroup, and is most extremein T. mulaiki.3) Reduction of protuberances. Troglobiticspecies are noticeably smoother in appearance thanother Texella as a result of an overall reduction ofbody sculpturing and other protuberances. Thebody surfaces are almost completely devoid of tubercles(including anterior tubercles). The cuticularmicrotubercles are small, giving a fine rugosity.Sexually dimorphic structures, female TrIV tubercle,male TrIV spur, and POP, are reduced in sizeor completely lost.4) Depigmentation. A loss of pigmentation ismost apparent in the troglobitic species.It is possible to arrange the species of Texella onthe basis of increasing troglomorphy. The leasttroglomorphic are the epigean species. Of these T.deserticola, with the highest LII/SL ratio and somereduction of anterior tubercles and depigmentation,would be most troglomorphic. Of intermediatetroglomorphy are the troglophiles, cavernicolousspecies having well developed eyes. In this groupT. brevistyla and diplospina have the lowest LII/SLratios and a relatively high number of anterior tubercles.The troglobitic species range from the moderatelymodified, T. welbourni and reyesi, to the extremelymodified, the mulaiki infragroup.The fact that troglomorphy appears to be derived,using T. bifurcata as outgroup, suggests the use ofthese characters in phylogenetic analysis. Using themost obvious gaps in the troglomorphic characterspectrum, three potential clades can be identified:all cavemicolous species (cave habitation and LII/SL2I@_..........I3oMap 3.-Distribution and area c1adogram of the subgroups and infragroups of the Texella mulaiki species group. Numbers: I,brevistyla subgroup; 2, longistyla infragroup; 3, mulaiki infragroup; 4, bi/obara infragroup; 5, brevidenta infragroup; 6, spinopercainfragroup; and 7, reddelli infragroup.168