ELLIOTT ET AL.: THE CAVE FAUNA OF CALIFORNIA 
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Lava Beds National Monument, and summarized the fauna in these and other volcanic caves in 
western North America. Elliott et al. (1985, 2003a-b) reported on California’s cave biodiversity at 
biospeleology meetings. The arachnologist, Willis Gertsch, of the American Museum of Natural 
History identified California as a hot spot with at least 20 troglobitic spiders (Gertsch 1992). Peck 
(1998) identified the Sierra Nevada foothills (our Sierra Nevada North) as a troglobite hotspot in 
North America, and listed 60 troglobitic species from California in his national checklist of cave 
animals. Peck also documented the diversity of fungus beetles (Leiodidae) in caves of California 
and the world in general. 
Culver et al. (2000) mentioned the Mother Lode karst region as having a significant cave obli¬ 
gate fauna on the continental scale, but gave no details. Culver, Christman, Elliott, Hobbs, and Red- 
dell (2003) included the Mother Lode in an analysis of nine North American karst regions based 
on genera. The 2003 paper found that the Mother Lode grouped generally with Texas, the 
Guadalupe Mountains of New Mexico, the Black Hills, and the Driftless Area of Iowa, but was fair¬ 
ly dissimilar to other regions. At that time only 20 troglobites and 3 stygobites were known from 
the Mother Lode region. The Mother Lode (Sierra Nevada North) now harbors 32 troglobites, 
3 stygobites, and 6 phreatobites, nearly doubling what we knew in 2003. 
The California cave fauna lacks the troglobitic vertebrates and larger crustaceans that occur in 
many eastern U.S.A. and Mexican faunas, presumably because of limited aquatic habitats in caves, 
but California is rich in minute phreatobites. Crickets, ecologically important trogloxenes and 
troglophiles in most U.S. cave faunas, are sparse or absent in many California caves. An important 
cave, Clough Cave, may lack crickets while Lilbum Cave, also important, has two species! 
Some of the genera present in Californian subterranean habitats are widespread in the U.S. 
(e.g., Stygobromus, Foveacheles, Poecilophysis, Oncopodura, and the isopod Caecidotea ). Twelve 
genera exhibit considerable California endemism or are limited to the western U.S. Eight genera 
(the isopods Bowmanasellus and Calasellus, the pseudoscorpions Australinocreagris and Fissil- 
iceagris, the harvestman Banksula, and the millipedes Sequoiadesmus, Speoseya and Speostriaria ) 
are endemic to California. The millipede Plumatyla is found in a limited range in California and 
Oregon. The millipede Nevadesmus is limited to Nevada and a cave in the SNS, and 
Pratherodesmus is limited to the SNS and caves in Arizona. The scorpion genus Uroctonus is lim¬ 
ited to the western U.S. So, California has eight state endemic cave genera, but shares some gen¬ 
era with Oregon, Nevada, and Arizona. 
Several groups exhibit significant range disjunctions, some of which relate to ancient vicari- 
ance events, such as continental drift. Telema spiders are known from the western U.S. and the 
Pyrenees, and Meinertophilus centipedes are known from California and Portugal. A third genus, 
the pseudoscorpion Pseudogarypus, is represented by four species in the western U.S. and related 
genera in Tasmania. In contrast the rhagidiid mite genera Foveacheles and Poecilophysis have 
many species of troglophiles and trogobites in American caves, relicts of forms that probably dis¬ 
persed circumboreally during the Quaternary across northern North America and Europe. 
The cave fauna of the Mojave Desert exhibits a distinct zoogeographic pattern. The fauna is 
extremely restricted because of the limited number of caves and extreme aridity, but the limited 
fauna exhibits a close zoogeographic affinity to the caves of Arizona, New Mexico, Texas, and 
northern Mexico. Seven genera of troglobites are known from the region. The opilionid Texella is 
known only from California and Texas. The schizomid Hubbardia and the troglophilic millipede 
Colactis are genera with distributions extending south and east of California; the closest relatives 
of the two California species are from Arizona. Three troglophilic species of the beetle Rhadine 
represent a widespread genus with troglobitic species restricted to Texas and northern Mexico, and 
troglophiles from there to New Mexico and California. In addition, the only troglophilic pseudo- 
