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Agastochizomus lucifer: Rowland, 1971a: 13 (erroneousspelling).Type-locality.-Sotano de la Tinaja, 10 km ~ECiudad Valles, San Luis Potosi, Mexico.Distribution.-Known only from three caves in theSierra de El Abra, near Valles, San Luis Potosi. SeeFig. 21.Records.-San Luis Potosi: Sotano de Matapalma,Sotano de la Tinaja, and Sotano de Yerbaniz.Discussion.-This is the largest species in the orderSchizomida. It is abundant on silt and along walls inSotano de la Tinaja. Although Brignoli (1974a) hasreservations about considering any schizomid to be atroglobite, the habitat and general facies of this andthe preceding species leave little doubt but that theyare restricted to the cave habitat.Famity SchizomidaeThe family Schizomidae includes 24 species whichhave been reported from the cave habitat in ~lexico,Guatemala, and Belize. Twelve of these are consideredto be troglobites; eight have been describedand are discussed below. The remaining species showno indication of adaptation for a cave existence, andsome are also known from epigean collections.Rowland and Reddell (1979) have subdivided theNew World schizomids of the genus Schizomus intoseven species groups. The dumitrescoae group is representedonly in the Antilles and Costa Rica. Althoughseveral species are known only from caves,their ecological status is uncertain. The simonisgroup ranges from northern South America to CostaRica; none are known from caves. The briggsi groupis known only from Arizona and California in theUnited States, with one species, S. shoshonensis(Briggs and Hom), being an apparent troglobile inUpper Shoshone Cave, Inyo County, California.The brasiliensis group ranges from Brazil tosouthern Mexico. Two species of this group haveinvaded caves. Schizomus stewarti Rowland is knownonly from Cueva del Guayabo, Oaxaca. Schizomustrilobatus Rowland is a dark species with distincteyespots and is known only from Grutas del Cocona,Tabasco. The only other brasiliensis group speciesknown from 1exico is S. lacandonus Rowland fromLas Ruinas de Palenque, Chiapas.With the exception of one species, the mexicanusgroup is restricted to Mexico, Belize, and Guatemala,where it is abundantly represented in caves. Schizomusportoricensis (Chamberlin) has been collec tedfrom Ecuador, the Galapagos Islands, southeasternMexico, the Antilles, and southern Florida. Peripheralpopulations are all parthenogenetic; parthenogeneticpopulations also occur in caves in the Yucatan Peninsula(Rowland and Reddell, 1977). Six species of themexicanus group are probably cave-adapted formsand are discussed below. Schizomus mexicanus Rowlandis known both from caves and the surface in theSierra de EI Ahra and in the lowland Sierra de Guatemala.Schizomus moisii Rowland is a dark specieswith distinct eyespots; it is known only from Grutasde Monteflor, Oaxaca. An undescribed species fromGrutas de Cacahuamilpa, Guerrero, lacks eyespotsand may be a troglobite.The pecki group is known only from sou themMexico, Guatemala, and Belize. Schizomus firstmaniand S. pecki are apparently troglobites and are discussedbelow. Schizomus sbordonii Brignoli is a trog­10phiJe described from Grutas de Atoyac, Vera(;ruz.Undescribed species from caves ncar Comilan, Chiapas,and from Grutas de :\lontef!or, Oaxaca, areapparently troglophiles. An undescribed species fromS1. Herm an's Cave, Belize. lacks eyespots and is probablya troglobile.Four species have been described in the goodnightorumgroup. One species from Yucatan and asecond from Chiapas are known only from the surface.The remaining species are represented only incave collections but show no modifications for cavelife. Schizomus lanceolatus Rowland is known onlyfrom Cueva del Diablo, Veracruz: S. silvino Rowlandand Reddell has been collected only in Gruta de Silvino,habal, Guatemala. See Fig. 22 for the distributionof troglophili(; Schizomus in J\lexico and Guatemala.Schizomus bartolo RowlandSchizomus sp.: Reddell, 1967a:25; Reddell, 1971b:28 (Grutas de San Bartolo record only).Schizomus bartolo Rowland, 1973a:13-16, 18, fig.11-13; Rowland, 1973c:135, 137; Rowland,1975a:34, 166, 169, 173-174, 176,177,214-215,218-219, 222-223, 228-229, 366-367, 368-369,394, fig. 158, 174, 193, 292; DUlIlitreseo, 1977:157: Rowland and Reddell, 1977:80, 83, 84, fig.2; Rowlano and Reddell, 1979a:163.Type-locality.-Gruta de San Bartolo, 16 km SSWMonterrey, Nuevo Leem, Mexico.Distribution.-Known only from Grutas de SanBartolo. See Fig. 23.Records.-Nuevo Leon: Grutas de San Bartolo andGruta Sur de San Bartolo.Discussion.-Grutas de San Bartolo is located in adesert ref,rion, and S. bartolo is apparently an isolatedpopulation now restricted to the cave habitat. It ismost closely related to S. firstmani. Grutas de San126