Sidymella rubrosignata is a species of crab spider

Crab spider

Crab spider is a common name applied loosely to many species of spiders, but most nearly consistently to members of the family Thomisidae...

 found in Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

. A common spider, often seen on Dianella

Dianella (genus)

Dianella is a monocot genus of flowering plants. They are commonly called flax lilies.In the APG II system of plant classification, Dianella was placed in the family Hemerocallidaceae...

 plants.

Like all Thomisid spiders, it does not make a web snare. But they patiently wait for prey to appear nearby. Prey is insects, or occasionally other small spiders.

Description

Often these spiders are a well camouflaged green, making their presence difficult to discern on green leaves or flowers. Occasionally they may be yellow, light brown or reddish. Body length: male 4.5 mm, female 8 mm. Males slimmer and smaller.

The front pair of legs are much longer than the other two pairs of legs. The abdomen is trapezium shaped, with a pair of dorsal humps, with a red patch on each of them. The cephalothorax

Cephalothorax

The cephalothorax is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. The word cephalothorax is derived from the Greek words for head and thorax...

 is pear shaped.

Egg Sac

The egg sac is in a leaf, with the tip folded back to cover the eggs. The leaf edges are curled around by silk to provide protection. Eggs 0.8 mm in diameter, non sticky, cream in colour. Usually 20 to 35 eggs in each egg sac.

Taxonomy

Described by in 1874 by Ludwig Koch

Ludwig Carl Christian Koch

Ludwig Carl Christian Koch was a German entomologist and arachnologist.He was born in Regensburg, Germany and died in Nuremberg, Germany. He studied in Nuremberg, initially law, but then turned to medicine and science...

. This spider was originally placed in the genus Sidyma

Sidyma (moth)

Sidyma is a genus of moths in the Arctiidae family.-Species:* Sidyma apicalis Moore, 1878* Sidyma albifinis Walker, 1856-References:* *...

 by Simon

Eugène Simon

Eugène Simon was a French arachnologist. His many taxonomic contributions include categorizing and naming many spiders, as well as creating genera such as Anelosimus, Psellocoptus and Phlogius....

 in 1895. However, this name was already used by Walker

Francis Walker (entomologist)

Francis Walker was an English entomologist. He was one of the most prolific authors in entomology, and stirred controversy during his later life as his publications resulted in a huge number of junior synonyms....

 in 1856 for a genus of moths. In 1942 Strand

Embrik Strand

Embrik Strand was an arachnologist who classified many insect and spider species, including the greenbottle blue tarantula....

 renamed the genus Sidymella.