Harvestman, Bee Creek Cave

Texella reddelli

phylum: Arthropoda

class: Arachnida

order: Opiliones

family: Phalangodidae

status: Endangered, ESA

range: USA (Texas)

Description and biology

Harvestmen are eyeless spiders. They are often called daddy longlegs because they have small rounded or oval bodies to which four pairs of long, slender legs are attached. The Bee Creek Cave harvestman's body is orange or light yellowish-brown in color and measures only 0.07 to 0.1 inch (0.17 to 0.25 centimeter) long.

This harvestman is a slow-moving, predatory species. It grasps its prey with its pedipalps (pronounced PEH-de-palps; a pair of specialized appendages or limbs located near its mouth). Its diet includes tiny, hopping insects called collembolans.

Biologists (people who study living organisms) have no information on the mating habits of this species. Young Bee Creek Cave harvestmen are white to yellowish-white in color.

Habitat and current distribution

Bee Creek Cave harvestmen inhabit underground caves in limestone rock in the Edwards Plateau region in Travis County, Texas. In these caves, the harvestmen are usually found under rocks in total darkness or in dim twilight. The species requires stable temperatures, high humidity, and a steady supply of small invertebrates on which to feed.

History and conservation measures

The primary threat to the Bee Creek Cave harvestman and other cave invertebrates (animals with no backbone) in its range is the loss of its habitat. Residential and urban areas continue to grow in this region. As a result, many caves have been paved over or filled in. Because the caves are formed by seeping water, any change or alteration in the flow of that water can change the environment of a cave. To meet the needs of these newly populated areas, much of this water has been diverted. Some caves have become dry while others have become flooded. Pollution from populated areas has also seeped into the groundwater, and the water in many caves has become contaminated.

Conservation efforts are underway to protect the habitat of the Bee Creek Cave harvestman and other endangered species. A protected area measuring approximately 7,000 acres (2,800 hectares) has been proposed.