Tree trunk spider

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Tree trunk spider
Temporal range: Cretaceous–present
Hersilia sericea 300596667 541628328.jpg
female H. sericea from South Africa
Hersilia.okinawaensis.male.-.takinawa.jpg
Male Hersilia okinawaensis
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Araneae
Infraorder: Araneomorphae
Family: Hersiliidae
Thorell, 1869
Diversity
16 genera, 206 species
Distribution.hersiliidae.1.png

Hersiliidae is a tropical and subtropical family of spiders first described by Tamerlan Thorell in 1869, [1] which are commonly known as tree trunk spiders. They have two prominent spinnerets that are almost as long as their abdomen, earning them another nickname, the "two-tailed spiders". They range in size from 10 to 18 mm (0.4 to 0.7 in) long.

Contents

Behavior

Rather than using a web that captures prey directly, they lay a light coating of threads over an area of tree bark and wait for an insect to stray onto the patch. When this happens, they encircle their spinnerets around their prey while casting silk on it. When the insect is immobilized, they can bite it through the shroud.

Diversity

Hersiliidae is an entelegyne family (characterized primarily by the nature of the female genital system), and together with the family Oecobiidae traditionally formed the superfamily Oecobioidea. [2]

The family consists of about 206 species divided into sixteen genera. [3] It has a global distribution in tropical and subtropical regions, with only a few species being found north of the 40°N parallel.

Description

All members are ecribellate (lack the cribella or perforated plates which produce multiple, exceptionally fine strands of silk) and are recognizable by the pair of exceptionally long spinnerets set at the tip of the abdomen. [2]

They have eight eyes, set in two curved rows. Hersiliidae are small to medium-sized spiders and are active day and night. They are very well camouflaged when stationary on the trunk of a tree and aligned with the bark markings. [4]

Genera

Genera

As of October 2025, this family includes sixteen genera: [3]

Extinct genera

See also

References

  1. Thorell, T. (1869). "On European spiders". Nova Acta Regiae Societatis Scientiarum Upsaliensis. 3 (7): 109–242.
  2. 1 2 Stoev, Pavel; Dunlop, Jason; Lazarov, Stoyan (2009). A life caught in a spider's web. PenSoft Publishers. p. 76. ISBN   978-954-642-502-7.
  3. 1 2 "Family: Hersiliidae Thorell, 1869". World Spider Catalog. doi:10.24436/2 . Retrieved 2025-10-07.
  4. Whyte, Robert; Anderson, Greg (2017). A Field Guide to Spiders of Australia. Csiro Publishing. p. 157. ISBN   978-0-643-10708-3.