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Order of the Month
Spider Relatives
by John Jackman
| Ticks and Mites | Whipscorpions |
| Scorpions | Harvestmen |
Ticks and Mites, [Acari]
Ticks are blood feeders. Ticks have four life stage: eggs,
larvae, nymphs, and adults. Larval ticks, sometimes called “seed ticks”,
only have six legs while the nymphs and adults have eight legs. Ticks
typically feed once per life stage and most change from one host between
life stages.
Mite are generally small and highly variable in shape and
behavior. Mites can be predators, plant feeders or scavengers. Some of
them are even aquatic. Most mites are barely visible to see or even
microscopic.
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Whipscorpions, [Uropygi]
Whipscorpions have pinchers in front and a long thin tail out
the rear. When disturbed they can spray acetic acid (vinegar). One of the
common names is vinegaroons. This critter is mentioned in the tale of
Judge Roy Bean from Lantry, Texas. Vinegaroons are limited to the western
and drier parts of Texas.
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Scorpions, [Scorpionida]
Scorpions are well know for their curved stingers and the
pinchers that reach forward. They are well equipped to defend themselves.
None of the scorpions in Texas are considered hazardous. However, they can
give a powerful sting. Individual reaction to the stings varies with some
people hardly bothered to severe reactions in others.
The only scorpion recorded in East Texas is the striped bark
scorpion, Centruroides vittatus. This scorpion is the most common and
widespread species in Texas.
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Harvestmen, [Opiliones]
The best known members of this group are called “daddy long
legs.” However, there are several short legged types too. There is a story
that daddy long legs have one of the most toxic chemicals known to man.
However, there is no scientific paper that verifies that claim. Therefore,
that story should be considered an “old wives tale.”
Harvestmen have their body compacted and it appears to be a
single globular unit. They have their eyes on a single stalk. The mouth
parts are weak and could not inject poison. Harvestmen feed on dead
insects and other arthropods.
They often hide in dark places during the day and forage for
food at night. Congregations of them can number in the hundreds. When they
are disturbed they shake or vibrate quickly appearing to be doing rapid
“push ups.”