prowling spiders (Family Eutichuridae)

Prowling spiders (Family Eutichuridae; formerly known as Miturgidae)

There are three species of prowling spiders known from Ohio. This represents <1% of our spider species. One species (yellow sac spider) is very common in buildings.

Characteristics of Eutichuridae:

  • leg tips with dense claw tufts and scopulae which permits them to climb smooth vertical surfaces with ease
  • conical anterior spinnerets, closely spaced
  • usually pale, nocturnal spiders
  • chelicerae often somewhat long
  • found on vegetation, often in houses

These sac spiders are pale colored, tan, light yellow, or pale greenish.  They hunt at night, running rapidly over surfaces and vegetation in search of prey. They fuel their constant running by feeding on sugary plant nectar when they encounter it in flowers or nectaries.  The yellow sac spider (Cheiracanthium mildei) is one of the most common spiders in houses and other buildings. During the day they can often be found in a thin silk cocoon in corners of structures, often at the join of a wall and the ceiling.

Ohio Examples:

Yellow Sac Spider (Cheiracanthium mildei) female

Yellow Sac Spider (Cheiracanthium mildei) female

photo of yellow sac spider

yellow sac spider (Cheiracanthium mildei)

photo of yellow sac spider

yellow sac spider (Cheiracanthium mildei)

photo of yellow sac spider in cocoon

yellow sac spider (Cheiracanthium mildei) in her thin cocoon near the ceiling

photo of yellow sac spider

yellow sac spider (Cheiracanthium mildei)

Strotarchus piscatorius subadult male

Strotarchus piscatorius subadult male