Reticulidia halgerda is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of sea slug

Sea slug

Sea slug is a common name used for several different groups of saltwater snails that either lack a shell or have only an internal shell, in other words this name is used for various lineages of marine gastropod mollusks that are either not conchiferous or appear not to be.The phrase "sea slug" is...

, a dorid nudibranch

Nudibranch

A nudibranch is a member of what is now a taxonomic clade, and what was previously a suborder, of soft-bodied, marine gastropod mollusks which shed their shell after their larval stage. They are noted for their often extraordinary colors and striking forms...

, a shell-less marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod mollusk in the family Phyllidiidae

Phyllidiidae

Phyllidiidae is a family of sea slugs, dorid nudibranchs, marine gastropod mollusks in the superfamily Phyllidioidea.This family is within the clade Euctenidiacea .-Distribution:...

.

Description

Reticulidia halgerda grows to a maximum length of 7.0 cm. This species is different externally and internally from species in the Phyllidia

Phyllidia

Phyllidia is a genus of sea slugs, dorid nudibranchs, shell-less marine gastropod molluscs in the family Phyllidiidae.-Species:Species in the genus Phyllidia include:* Phyllidia alyta Yonow, 1996* Phyllidia babai Brunckhorst, 1993...

and Phyllidiopsis

Phyllidiopsis

Phyllidiopsis is a genus of sea slugs, dorid nudibranchs, shell-less marine gastropod molluscs and is the largest genus within the family Phyllidiidae....

genera, both of which also have yellow coloration and tuberculate ridges. Reticulidia halgerda does not have spiculose tubercles, but instead has reticulate ridges on the notum that are smooth. Phyllidia ocellata

Phyllidia ocellata

Phyllidia ocellata is a species of sea slug, a dorid nudibranch, a shell-less marine gastropod mollusk in the family Phyllidiidae.- Distribution :This species is widely distributed throughout the Indo-West Pacific Ocean the Red Sea.-Description:...

, Phyllidia tula, Phyllidia varicosa

Phyllidia varicosa

Phyllidia varicosa is a species of sea slug, a dorid nudibranch, a shell-less marine gastropod mollusk in the family Phyllidiidae.- Distribution :...

, and Phyllidia coelestis all have a different foregut

Foregut

The foregut is the anterior part of the alimentary canal, from the mouth to the duodenum at the entrance of the bile duct. At this point it is continuous with the midgut...

as well as tubercles capped with yellow coloration. Furthermore, unlike Reticulidia fungia, Reticulidia halgerda does not possess a broad bluish white border.

Distribution

This species is found in numerous locations in the central and western Pacific Ocean, including East Australia, Taiwan, the Philippines, Indonesia, the Marshall Islands, and Fiji.