Nannochloropsis is a genus of alga comprising approximately 6 species. The genus in the current taxonomic classification was first termed by Hibberd (1981). The species have mostly been known from the marine environment but also occur in fresh and brackish water. All of the species are small, nonmotile spheres which do not express any distinct morphological features, and cannot be distinguished by either light or electron microscopy. The characterisation is mostly done by rbcL gene and 18S rDNA sequence analysis. It is different from other related microalgae in that it lacks chlorophyll

Chlorophyll

Chlorophyll is a green pigment found in almost all plants, algae, and cyanobacteria. Its name is derived from the Greek words χλωρος, chloros and φύλλον, phyllon . Chlorophyll is an extremely important biomolecule, critical in photosynthesis, which allows plants to obtain energy from light...

 b and c. Nannochloropsis is able to build up a high concentration of a range of pigments such as astaxanthin

Astaxanthin

Astaxanthin is a carotenoid. It belongs to a larger class of phytochemicals known as terpenes. It is classified as a xanthophyll, which means "yellow leaves". Like many carotenoids, it is a colorful, lipid-soluble pigment. Astaxanthin is found in microalgae, yeast, salmon, trout, krill, shrimp,...

, zeaxanthin

Zeaxanthin

Zeaxanthin is one of the most common carotenoid alcohols found in nature. It is important in the xanthophyll cycle. Synthesized in plants & some micro-organisms, it is the pigment that gives paprika , corn, saffron, and many other plants & microbes their characteristic color.The name is derived...

 and canthaxanthin

Canthaxanthin

Canthaxanthin is a carotenoid pigment widely distributed in nature. Carotenoids belong to a larger class of phytochemicals known as terpenoids. The chemical formula of canthaxanthin is C40H52O2. It has E number E161g and is approved for use in the EU and USA however it is not approved for usage in...

.
The algae have a very simple ultrastructure, and reduced compared to neighbouring taxa. They have a diameter of about 2 micrometers. It is considered a promising alga for industrial applications because of its ability to accumulate high levels of polyunsaturated fatty acids. It is mainly used as an energy-rich food source for fish larvae and rotifer

Rotifer

The rotifers make up a phylum of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John Harris in 1696, and other forms were described by Anton van Leeuwenhoek in 1703...

s.
Recently, Nannochloropsis has been investigated for biofuel production. (see Nannochloropsis and biofuels

Nannochloropsis and biofuels

Nannochloropsis is a genus of alga within the heterokont line of eukaryotes, that is being investigated for biofuel production. One marine Nannochloropsis species has been shown to be suitable for algal biofuel production due to its ease of growth and high oil content , mainly unsaturated fatty...

). Restaurant "A Poniente" of El Puerto de Santa María

El Puerto de Santa María

El Puerto de Santa María is a municipality located on the banks of the Guadalete River in the province of Cádiz, Spain. , the city has a population of c...

 (Cádiz

Cádiz

Cadiz is a city and port in southwestern Spain. It is the capital of the homonymous province, one of eight which make up the autonomous community of Andalusia....

, Spain

Spain

Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

) is using Nannochloropsis gaditana for human food.

Species

The species currently recognised are:

• N. gaditana
• N. granulata
• N. limnetica
• N. oceanica
• N. oculata
• N. salina