ELLIOTT ET AL.: THE CAVE FAUNA OF CALIFORNIA 
43 
Table 9. Twelve high-biodiversity groundwater sites with 26 species and 21 SSEs (single-site endemics). 
*The site score is the number of phreatobites X SSEs. The regional score is the sum of site scores within a 
region. 
Region 
County 
Site 
Type 
Phreato¬ 
bites 
SSEs 
Site 
Score* 
Regional 
Score 
Reg. 
Sites 
Bay Area/Delta 
Butte 
unnamed spring on 
Rock Creek 
Spring 
1 
1 
1 
Marin 
Cronan Creek 
Stream 
2 
1 
2 
Marin 
Redwood Creek, Muir 
Woods 
Hyporheos 
1 
1 
1 
Napa 
unnamed spring 
Spring 
2 
1 
2 
Sonoma 
unnamed spring, just east 
of Maacama Creek Bridge 
Spring 
2 
2 
4 
10 
5 
Coast Ranges 
Los Angeles 
Malibu Creek 
Hyporheos 
2 
1 
2 
San Diego 
San Clemente Canyon Park, 
La Jolla 
Hyporheos 
3 
3 
9 
San Diego 
dry stream bed in San 
Clemente Park, La Jolla 
Hyporheos 
1 
1 
1 
San Diego 
Otay Reservoir 
Hyporheos 
1 
1 
1 
San Diego 
San Diego River 
Hyporheos 
1 
1 
1 
San Diego 
stream in Otay Reservoir 
Hyporheos 
1 
1 
1 
Santa Barbara 
Montgomery Spring 
Spring 
1 
1 
1 
16 
7 
Klamath Mountains 
Siskiyou 
subterranean habitat at 
Greenview 
Well 
1 
1 
1 
1 
1 
Lava Flows North 
Modoc 
unnamed spring at the 
Stough Reservoir 
Campground 
Spring 
1 
1 
1 
1 
1 
San Joaquin Valley 
Stanislaus 
Tuolumne River 
(River Mile 31.5) 
Hyporheos 
1 
1 
1 
1 
1 
Sierra Nevada North 
Placer 
Lake Tahoe, center of lake 
Lake 
4 
2 
8 
24 
1 
Sierra Nevada South 
Fresno 
unnamed spring at 
Shaver Lake 
Spring 
1 
1 
1 
1 
1 
studied P. sierra in 13 caves, and he found that the frog used the crepuscular zone of caves to 
escape hot, dry conditions and nearby streams that dried out seasonally, making a good case that 
the frog is a trogloxene. This frog vacates the caves during winter rains and returns to its streams. 
Salamanders are the major amphibian group that can adapt to the cave environment. A rela¬ 
tively large number of American salamander species are highly specialized stygobites, as neotenic 
species or populations. The only terrestrial/amphibious troglobitic salamander is Eurycea spelaea 
(grotto salamander) of the Ozark Plateau in Missouri and Arkansas, where water resources are 
abundant. 
The geologic context of caves in California is not conducive to the evolution of troglobitic ver¬ 
tebrates. There is a lack of large cave systems due to the very limited extent of soluble rock and 
lava flows. As a consequence, cave habitats are extremely fragmented in California. This situation 
is illustrated by the observation that approximately 50% of California subterranean obligates are 
single-site endemics. In addition, aquatic habitats that would allow the evolution of stygobites, are 
also quite limited. 
