Goetze: Scorpions get a bad rap. They are secretive, unassuming hunters

Some of the most feared invertebrate animals are scorpions. Their name often conjures images of a dangerous, sneaky, and treacherous animal, but this impression is largely incorrect or biased.

Scorpions were among the first arthropods to inhabit earth’s terrestrial environments, and fossil scorpions older than 430 million years have been discovered.

Scorpion as symbol

More than 1,500 scorpion species occur worldwide and, understandably, their cultural and symbolic meanings differ. Scorpion symbolism ranges from protection, transformation, healing and rebirth to betrayal, danger, death and mystery.

Eighteen scorpion species have been confirmed from Texas with the sparsely populated Trans-Pecos region home to the largest number — 14.

Daytime hideouts

Because of their nocturnal and secretive behaviors, scorpion and human encounters are less frequent than encounters between humans and other arthropods such as insects and spiders.

Scorpions spend the daylight hours in moist areas underneath rocks, within brush piles, under tree bark, and, sometimes unfortunately, within or underneath buildings, in basement areas, storm cellars, and other structures and — because they are adept climbers — in attic spaces.

Therein lies the stinger

The most common scorpion in Northcentral Texas and Southwestern Oklahoma is the striped bark scorpion (Centruroides vittatus). Centruroides translated from Greek means “sharp-ended tail,” probably in reference to its long, curved, tail-like abdominal segments terminating in a sharp stinger.

The meaning of vittatus is “ribbon or band,” which aptly describes the two sometimes broad, dark dorsal bands of the striped bark scorpion.

Besides the dark, dorsal bands, dark triangular area on the head and often dark, stinger tail segment, the overall dorsal color of striped bark scorpions is pale yellow with a lighter colored venter — belly.

Scorpions have eight walking legs and a pair of elongated, distinctive pedipalps ending in robust pincers which are used to help capture and sometimes tear apart prey.

Scorpions’ bodies are dorso-laterally compressed and appear somewhat flattened. Whenever the scorpion moves about, its long, highly flexible tail is usually held in an upright, looped, or slightly curled position above the back.

Six eyes but still can't see well

Even though the striped bark scorpion has a pair of fairly large eyes on top of its head and another pair of smaller eyes on each side of the head (six eyes in total), its vision is not especially keen. Most of its prey is detected more by touch than by sight.

Its poor eyesight may contribute to accidental encounters with humans.

Light detection devices

One characteristic which helps humans see scorpions is the scorpions’ property of fluorescing when exposed to ultraviolet light.

Scientists aren’t sure why scorpions are fluorescent, and explanations range from the fluorescence serving as a warning color and/or an attractant to some night flying insect prey to a means of communication within and between scorpion species.

Researchers have discovered that scorpions use their fluorescent tails and bodies as light-detecting devices to help determine if it is safe to emerge from their retreats and begin hunting for prey and/or potential mates.

Scorpions don’t need to eat on a daily basis; therefore, this method of measuring nocturnal light levels compensates for their poor vision and helps scorpions choose optimal hunting times!

Scorpio prey

Whenever striped bark scorpions emerge from diurnal retreats, these opportunistic hunters capture various insects such as beetles, crickets, flies, and moths and other arthropods including pill bugs, spiders, and even other scorpions.

Scorpions will also catch and consume snails, lizards, snakes and small rodents whenever these prey animals can be subdued. Scorpion venom is a mixture of several types of neurotoxins which, consequently, makes the venom more effective upon a wider range of prey species and helps the scorpions overpower and capture prey.

However, as the old saying goes, “turnabout is fair play”, and scorpions are preyed upon by other insects, birds, reptiles, amphibians, bats, and even grasshopper mice.

The dance of the scorpions

Scorpions undergo a type of invertebrate hibernation known as diapause during winter months and mate during fall, spring and summer months.

Scorpion courtship behaviors are complex and often include an extended dance called the Promenade `a Deux wherein dancers grasp their partner’s pedipalps and move in circles.

If successful, the male scorpion will direct his partner over a packet of his sperm (called a spermatophore) placed on the ground, and she will draw the sperm into her genital pore and fertilize her eggs. The eggs develop inside the female’s body, and young scorpions are born alive after an extended gestation period of approximately eight months.

Hitching a ride with mom

Young scorpions (brood size averages about 26) climb onto their mother’s back and are cared for and protected until their first molt: after which the young disperse. Scorpions are relatively long-lived arthropods and average lifespans of striped bark scorpions range from 3–8 years.

Avoiding scorpions and their stings

Striped bark scorpions can deliver painful stings, but their venom isn’t especially dangerous to humans unless the victim has an allergic reaction. The pain and swelling associated with the sting may be reduced with cold compresses and over-the-counter analgesics.

Cleaning and disinfecting the sting area with a topical antibiotic are recommended.

Perhaps the best way to reduce scorpion encounters is to clear away brush, debris, wood piles and other suitable scorpion habitats near properties and homes. Inspect closets and other dark areas on a regular basis, seal cracks and openings around doors, windows, and other areas of the home.

Place sticky traps in appropriate areas, and wear shoes when walking in the dark.

Striped bark scorpions may be unwelcome in our homes but have been members of our region’s natural communities for far longer than humans.

Scorpions have a fearsome appearance and excellent defenses but are not especially aggressive toward humans. Remember that scorpions can’t see us very well; therefore, it’s easier for us to avoid them than visa-versa!

Jim Goetze is a retired professor of biology and former chairperson of the Natural Sciences Department of Laredo College with an avid interest in all aspects of the natural world. He can be contacted at gonorthtxnature@gmail.com.

This article originally appeared on Wichita Falls Times Record News: Goetze: Scorpions get a bad rap but are secretive, unassuming hunters