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PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES 
Series 4, Volume 64, Supplement 1 
Table 18 (continued). Clough Cave, Sequoia National Park, Tulare County, Sierra Nevada South Region, 
species list (58 species). 
Phylum/ Class 
Order 
Family 
Species 
Ecological 
classification 
SE 
Malacostraca 
Isopoda 
Trichoniscidae 
Brackenridgia heroldi 
Troglophile 
Chordata 
Mammalia 
Carnivora 
Procyonidae 
Procyon lotor 
Epigean 
Chiroptera 
Molossidae 
Tadarida brasiliensis 
Trogloxene 
Vespertilionidae 
Antrozous pallidus 
Trogloxene 
Vespertilionidae 
Corynorhinus townsendii townsendii 
Trogloxene 
Vespertilionidae 
Myotis evotis 
Trogloxene 
Rodentia 
Undetermined 
Rodentia 
Reptilia 
Squamata 
Colubridae 
Lampropeltis sp. 
SE Score 5.04 
Samwel Cave has a steel plate gate inside that is a barrier to wildlife. Samwel is an important cave 
for the entire western U.S.A. 
Empire Cave. Figure 116 is the map and Table 20 is the species list for Empire Cave, Santa 
Cruz County, Bay Area/Delta Region, including 76 species with 6 troglobites, 4 single-site 
endemics, and a rank of number 3 in the state. The cave contains roots, and it is heavily used and 
abused, but also was well-studied by biologists. Its moist environment harbors 2 tubificid worms, 
3 salamanders, 5 snails, occasional slugs, 2 stygobitic amphipods unique to the cave, a new species 
of stygobitic Caecidotea isopod, and a phreatobitic Calasellus isopod. The terrestrial arthropods 
include 1 mite, 7 spiders, 6 harvestmen, 2 troglobitic pseudo scorpions (1 known only from there), 
3 centipedes, 7 millipedes, an unidentified cricket, 12 beetles, 12 dipterans, and a symphylan. More 
than half of the fauna is epigean to trogloxenic (26 species) or troglophilic (16 species). 
Townsend’s western big-eared bat formerly occurred there, but not since increased usage of the 
cave since the opening of the surrounding college campus. Empire Cave’s fauna is quite different 
from caves in other regions. 
Clay Cave (Fig. 117), Napa County, Bay Area/Delta Region, ranks 4 th and is the most geo¬ 
logically odd of the top 20 caves, formed in Miocene Sonoma Volcanics, a continental packet of 
rhyolitic to andesitic volcanoclastic sediments and tephras (ash). Figure 117 is the map of Clay 
Cave and Table 21 details its fauna of 68 species, 22 of which are beetles (much of the field work 
was done by coleopterists). Five species are troglobites and 2 are single-site endemics. There are 
1 mite, 10 spiders, 3 harvestmen, 2 pseudoscorpions, 2 centipedes, 5 millipedes, 7 collembolans, 
22 beetles (2 troglobites in unusual families), 4 dipterans, 3 hemipterans, 1 ant, 1 moth, 1 cricket, 
1 terrestrial isopod, 1 salamander, a rodent, 2 snails, and a horsehair worm (Fig. 102). Sitting at 750 
m elevation, the cave is 229 m long and 38 m deep. The moist cave is formed by an underground 
steam that has eroded a soil pipe through the cemented ash. The cave may have originated along 
root casts in the bedded sediments that are mostly altered to smectite clay, locally stained with iron 
oxides. Subsequent invasion by seasonal streams has integrated the initial fist-sized soil pipes into 
vadose canyon passages (Bruce Rogers, pers. comm.) The cave descends steeply, and there are a 
number of squeezes along the narrow winding stream passage. There usually is standing water or 
a flowing stream with a seeping spring. The cave has roots, and there is a small number of crick¬ 
ets near the entrance. 
Lilburn Cave (Fig. 118), Kings Canyon National Park, Tulare County, is one of the two very 
large caves of California at 33.5 km long and 155 m deep, with an entrance elevation of 1,600 m. 
