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All six of the karst invertebrates protected under the BCCP were listed as endangered in September
of 1988 and live in only a few local caves. Though not much is known about them, they do have some
things in common. As invertebrates they do not possess an internal skeleton as humans do for
providing rigidity and form to their bodies. Rather, they have a rigid exterior, or exoskeleton,
for that function--hence the term "invertebrate". They are all troglobites, a name that describes
animals so completely adapted to a cave that they spend their entire life cycle there and can exhibit
loss of pigment and can lack functional eyes.
In every cave there are relationships between predator and prey. There is an exchange of energy when
these roles are acted out and as some animals and materials move into and out of the cave. In the
caves where endangered karst invertebrates live it is no different, and they play a vital role in
that piece of the web of life.
The primary threat to survival for these cave-obligated species is urban development. Complete loss
of habitat occurs when caves are filled in. Paving over caves or creating new openings can affect
hydrologic flow and change cave temperature and humidity beyond a range the species can tolerate.
Urban development also results in pollution from pesticides, fertilizers, roadway runoff, and other
chemicals that seep through soil and porous limestone to contaminant caves and groundwater. Fire
ants are also a serious threat to these animals since they enter caves and feed on or compete with
cave-dwelling animals. Go to the photo gallery to see images of these animals.
Tooth Cave ground beetle (Rhadine persephone)
Measuring in at about ¼ of an inch, this tiny, reddish-brown beetle is the largest of the protected
karst invertebrates. It does possess very small eyes though it lives its entire life in a cave.
It rapidly runs across the cave floor searching for tiny cave insects or can be found in areas of
deep, loose silt where it digs to search for cave cricket eggs. It has been documented in almost
30 local caves.
Tooth Cave pseudoscorpion (Tartarocreagris texana)
This is the second tiniest of the protected cave invertebrates at 3/16 of an inch long. Similar
to a scorpion, it has pinchers, though quite tiny, that it uses to catch its prey of small
invertebrates. It lacks any type of tail and has no eyes. It is typically found under rocks and
little is known about its habits or reproductive patterns.
Tooth Cave spider (Neoleptoneta myopica)
At 1/16 of an inch long, this pale, cream-colored spider is the tiniest of the protected cave
invertebrates. It has relatively long legs and rudimentary eyes. It can be found hanging from a
small tangle or sheet web from cave ceilings and walls seeking tiny invertebrates to eat.
Bee Creek Cave harvestman (Texella reddelli)
This small invertebrate is a light yellowish-brown and averages 1/8 inch long with long legs
typical of most harvestman. It lives in total darkness under rocks and doesn't have eyes.
Similar to other harvestman, it doesn't create a web, catching its prey of tiny insects as it
walks slowly about the cave.
Bone Cave harvestman (Texella reyesi)
Listed as endangered in September 1988, this long-legged harvestman is less than 1/8 inch long.
Similar to the Bee Creek Cave harvestman it is blind, is a pale orange-brown color, and feeds on
tiny invertebrates. It is typically found under rocks. Studies have indicated this species is
especially sensitive to low humidity and will retreat to the coolest and most moist places of a
cave during hot summers.
Kretschmarr Cave mold beetle (Texamaurops reddelli)
Listed as endangered in September 1988, this tiny dark-brown beetle is less than 1/8 inch long.
It has short wings, long legs, no eyes, and can be found in total darkness under rocks and organic
debris that has washed into the cave. Very little is known about this beetle including exactly
what it eats.
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