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~ 3.3 are synapomorphic); all troglobitic species(eye loss and LII/SL ~ 4.3 are synapomorphic); andthe mulaiki infragroup (reduction of eye mound,LII/SL ~ 9.9, etc. are synapomorphic). The factthat only the last group appears to be monophyleticsuggests that troglomorphic characters are primarilyadaptive.Indeed, it appears most probable that troglomorphyevolved several times in Texella. For example,the kokoweef group includes two troglophilic(T. kokoweef and shoshone) and one epigean species(T. desenicola). Since T. shoshone appears to bemore closely related to desenicola, it would seemmost parsimonious that troglomorphy evolved oncein the species group and was subsequently lost indesenicola. This may be further supported by thefact that desenicola, as noted above, is the mosttroglomorphic of the epigean species. However,one weakness in this argument is that it fails to takeinto account the relative time frame of phylogeneticand troglomorphic characters. In all probability thespeciation events in this group, judging by themorphological distinctness of the species and thebasal position of the group, must be old. If thedegree of troglomorphy is a function of time, thenthe presumed antiquity of these species should bereflected in their troglomorphic characters, which isnot the case (the species, especially kokoweef, arenot strongly troglomorphic). Thus, an equally, ifnot more, parsimonious argument would be that thecavemicolous habit and subsequent troglomorphicmodification is a more recent event, and one whichoccurred independently in the two species. Usingsimilar reasoning, it could be argued thattroglomorphy evolved independently at least seventimes in the mulaiki species group.Furthermore, and of possible use in understandingthe evolutionary patterns in Texella, is the clinalvariation in troglomorphic characters. This isspecies LnlSL(N) tarsal count ret/cor ant tubs TrlV f TrlV m popbifurcata (E) 2.6-3.1(22) 3-5-4-5 +/+ 9-12prs 0-2 tubs 1-3 tubs -bifurcata 3.3(1 ) 3-5-4-5 +/+lwkoweef 3.3-3.8(6) 3-5-4-5 +/+ 4-8prs 2 tubs long -shoshone 3.9-4.2(3) 3-5-4-5 +/+ 2prs 1 tub lon2 -desenicola (E) 3.4(\) 3-5-4-5 +\+ 2prs ? lon2 -junRi (E) 2.3-2.7(6) 3-5-4-5 +/+ 2-6prs I tub lon2 lar2ebrevistyla 2.6-3.2(1 \) 3-5-4-5 +/+ 8prs 2 tubs lon2 md-12longisrvla (E) 2.8(\) 3-5-5-5 +1+ 2prs ? lon2 medlonRisrvla 3.5-3.6(4) 3-5-5-5 +/+ 2-3prs I tub long medwelbourni 4.6(\) 3-5-5-5 -/- 5prs ? short smallhardeni 9.9-11.6(3) 3-6/8-4-5 -/- 1pr none tiny noneMarguerite Cave 9.4-11.2(2) 3-617-4-5 -/- ODr 1 tub ? ?watersi 11.1-12.9(5) 4-618-5-5 -/- 1pr none tiny smallmulaild 12.5-15.3(8) 4-5/8-5/6-5/6 -/- 0-lpr none none nonebi/obata (E) 2.6-2.8(3) 3-5-4-5 +/+ 2prs 1 tub short nonereddelli 3.8-4.2(7) 3-5-5-6 +/+ 4-5prs 2 tubs lon2 lar2ereyesi 4.3-8.7(71) 3/4-4/8-5/6-5/8 -/+ 0-2prs 0-1 tub md-lg sm-lgbrevidenta 3.3(1) 3-5-5-6 +/+ 4prs ? lon2 medgrubbsi 3.6-3.7(4) 3-5-5-5 +/+ 2prs 2 tubs lon2 md-12diDlosDina 2.6-3. \(9) 3-5-5-5/6 +/+ 4-6prs I tub lon2 md-12renkesae 3.2-3.4(5) 3-5-5-5 +/+ 4prs I tub lon2 md-12sDinoperca 3.4-4.3(13) 3-5-5-5 +/+ 3-4prs I tub 10nl( largefendi (E) 2.5-2.7(8) 3-5-5-5 +/+ 2-4prs 1 tub short nonehomi (E) 2.5-2.9(4) 3-5-4-5 +1+ 3prs I tub short noneTable 2.-Table of troglomorphic characters. Abbreviations: E = epigean species or populations; LlVSL = leg ill scute length; N= number of specimens measured; ret = retina; cor = cornea; ant tubs = number of paraocular anterior tubercles; pres) = pair(s);TrlV = trochanter rv; f = female; m = male; tubes) = tubercle(s); Ig = long, large; md, med = medium-sized; sm = small.169