Euophrys bulbus is a species of jumping spider

Jumping spider

The jumping spider family contains more than 500 described genera and about 5,000 described species, making it the largest family of spiders with about 13% of all species. Jumping spiders have some of the best vision among invertebrates and use it in courtship, hunting and navigation...

 found only in Taiwan

Taiwan

Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...

. This is a very small spider with a total length (excluding legs) of just over 3 mm. The sparsely hairy carapace

Carapace

A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...

 is dark brown with black margins and a black w-shaped mark about half way along the back. The legs are dark brown with greyish-black markings. The roughly cylindrical abdomen

Abdomen

In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...

 is marked generally with short blackish lines with three pairs of light depressions along the back with further light markings, a crescent flanked by diagonal lines, towards the rear.

This species can be distinguished from the similar Euophrys atrata by differences in the shape of the genitalia and the configuration of dentation on the chelicerae

Chelicerae

The chelicerae are mouthparts of the Chelicerata, an arthropod subphylum that includes arachnids, Merostomata , and Pycnogonida . Chelicerae are pointed appendages which are used to grasp food, and are found in place of the chewing mandibles most other arthropods have...

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