26 
PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 64, Supplement 1 
Table 2. The 57 troglobitic arachnids of California. D = described, unD = undescribed species. KM: Kla¬ 
math Mountains; LFN: Lava Flows North; SNN: Sierra Nevada North; SNS: Sierra Nevada South; MD: 
Mojave Desert; BD: Bay Area/Delta. 
Order 
Family 
Genus species 
D 
unD 
County (Cave) 
KM 
LFN 
SNN 
SNS 
MD 
CR 
Scorpiones 
Vaejovidae 
Uroctanus grahami 
1 
Shasta (Samwel Cave) 
Pseudo- 
scorpiones 
Chthoniidae 
Chthoniidae 
Aphrastochthonius 
2 
Calaveras 
Apochthonius grubbsi 
1 
Calaveras 
Neochthonius 
2 
2 
Calaveras, Tuolumne, Tulare, Santa Cruz 
Pseudogarypidae 
Pseudogarypus 
2 
Shasta, Calaveras, Tuolumne 
Neobisiidae 
A ustrafinocreagris 
1 
1 
Calaveras, Tuolumne 
Fissilicreagris 
1 
4 
Tulare, Santa Cruz 
"Microcreogris" 
2 
Calaveras, Tuolumne, Mariposa 
Parobisium yo Sem ite 
1 
Mariposa 
Chernetidae 
Tuberochernes 
1 
1 
Tulare, Inyo 
Larcidae 
Larca laceyi 
i 
Calaveras 
unplaced 
unplaced 
1 
Siskiyou (Lyon's Road Cave) 
Opiliones 
Taracidae 
Taracus flu yipileus 
1 
Shasta 
Phalangodidae 
Banksula 
8 
Placer, El Dorado, Amador, Calaveras, Tuolumne 
Calidna 
i 
Tulare 
Texella 
1 
Inyo (Titus Canyon Cave) 
Araneae 
Telemidae 
Usofila 
1 
Shasta, El Dorado, Calaveras, Tuolumne, Tulare 
Leptonetidae 
Calileptoneta 
1 
2 
Trinity, Calaveras, Tulare 
Linyphiidae 
Erigoninae 
1 
Amador, Tuolumne 
Linyphiinae 
1 
Tulare (Lilburn Cave) 
Oaphantes 
1 
Tulare (Paradise Cave) 
Spirembolus 
1 
Tuolumne, Tulare 
Nesticidae 
Nesticus potterius 
1 
Shasta 
Cybaeidae 
Cybaeozyga 
2 
Shasta 
Cybaeus 
1 
Shasta Co (Samwel Cave) 
Dictynidae 
Blabomma 
6 
Shasta, Amador, Calaveras, Tuolumne 
Yorima 
1 
Tulare 
Schizomida 
Hubbardiidae 
Hubbardia shoshonensis 
1 
Inyo (Shoshone Cave) 
Palpigradi 
Prokoeneniidae 
Prokoenenia 
1 
Amador, Calaveras 
Acari 
Rhagidiidae 
Foveacheles titanica 
1 
Calaveras, Tuolumne 
unplaced 
unplaced 
1 
Tulare 
26+ 
31 
= 57 Total 
Mojave Desert to Sierra Nevada North, but not from a sea cave. It was transplanted from McLean’s 
Cave to the Transplant Mine. Other species in the genus, all troglobitic, are known from Arizona, 
New Mexico, Texas, and eastern Mexico. 
Arachnids 
Members of the Class Arachnida are primitively cryptozoic organisms and denizens of moist 
dark habitats such as leaf litter, rock undersurfaces and crevices, including caves, where they con¬ 
stitute a significant part of the cavemicole fauna. Of the 928 terrestrial troglobite species recorded 
north of Mexico, 334 (36%) are arachnids (Peck, 1998). Similar results were found for the south¬ 
ern Cumberland Plateau, where the 52 arachnid troglobites are 35% of the fauna (Zigler et al. 
2014). The Appalachian karst has fewer arachnids, only 42 species or about 23% of the total, and 
in sharp contrast to that of Texas, which has 73 species, or 68% of its total (Culver et al. 2003). In 
California, arachnid troglobites are well represented and the 57 species (see Tables 2 and 3) repre¬ 
sent 57% of the fauna. This ric hn ess in species extends to higher taxonomic diversity; 7 of the 11 
arachnid orders in California caves are represented by at least one obligate cavemicole. In descend¬ 
ing order the common troglobites are pseudoscorpions (23), followed by spiders (18), and harvest- 
men (11). The same trend was found in the above studies, but with differing proportions: 161, 124, 
42 for the entire United States (Peck 1998) and 39, 8, 4 for the Cumberland Plateau (Zigler et al. 
2014); 62, 12, 5 for the Interior Low Plateau; and 23,15, 0 for Appalachia, which is unusual in lack¬ 
ing troglobitic harvestmen (Culver et al. 2003). In contrast, only 9 arachnid troglobites occur 
among Missouri’s 33 troglobites. Missouri is a mesic state with aquatic species being 60% of its 
