Morula granulata, common name

Common name

A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...

 the mulberry shell, 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 snail

Sea snail

Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

, a marine gastropod mollusk in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Muricidae

Muricidae

Muricidae, common name murex snails or rock snails, is a large and varied taxonomic family of small to large predatory sea snails. With approximately 1,600 living species the Muricidae represent almost 10% of the Neogastropoda. Additionally, 1,200 fossil species have been recognised...

, the murex snails or rock snails.

Description

The shell size varies between 18 mm and 30 mm. The conical, oblong shell is compact and contains no varices. It is covered with dark brown to black blunt knobs on a white background with spiral cords between the rows. The body whorl

Body whorl

Body whorl is part of the morphology of a coiled gastropod mollusk.- In gastropods :In gastropods, the body whorl, or last whorl, is the most recently-formed and largest whorl of a spiral or helical shell, terminating in the aperture...

 is covered with six rows of nodules. The outer lip is dentate with four to five teeth within. The narrow aperture

Aperture (mollusc)

The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....

 is blackish. The columella

Columella

Lucius Junius Moderatus Columella is the most important writer on agriculture of the Roman empire. Little is known of his life. He was probably born in Gades , possibly of Roman parents. After a career in the army , he took up farming...

 and the inner lip are white.

This globular shape, tight shell coiling, strong sculpture

Sculpture (mollusc)

The sculpture of a mollusc shell is the three-dimensional ornamentation on the outer surface, as distinct from the basic shape of the shell itself or colouration. Sculpture may be concave as well as convex. Sometimes it has microscopic detail. Sculpture refers to the calcareous outer layer, not the...

, a dentate outer lip and narrow aperture offers an added protection against shell-crushing predators, such as fishes and crabs.

This mollusc is a predator and feeds by drilling sedentary or semi-mobile prey. It eats only other molluscs, mainly gastropods of the genera Cerithium

Cerithium

Cerithium is a genus of small to medium-sized sea snails, marine gastropod mollusks in the family Cerithiidae, the ceriths. The genus is known from the Cretaceous to the Recent periods.- Species :Species within this genus include:...

, Rissoina

Rissoina

Rissoina is a large genus of minute sea snails, marine gastropod mollusks or micromollusks in the family Rissoidae.-Species:According to the World Register of Marine Species]] the following species with valid are included within the genus Rissoina : * Rissoina ambigua Gould* Rissoina angeli...

, Heliacus, and Bittium

Bittium

Bittium is a genus of very small sea snails, marine gastropod molluscs in the family Cerithiidae, the horn snails. - Species :Species in the genus Bittium include:* Bittium adamsi* Bittium aedonium * Bittium afrum...

, and the mussel Hormomya.

Imposex

Imposex

Imposex is a descriptive term applied to some sea snails, marine gastropod molluscs which, under the toxic effects of pollutants, develop sex organs that are in contrast to their actual sex...

 in Morula granulata is a bioindicator

Bioindicator

Biological indicators are species used to monitor the health of an environment or ecosystem. They are any biological species or group of species whose function, population, or status can be used to determine ecosystem or environmental integrity. An example of such a group are the copepods and other...

 for the presence of tributyltin

Tributyltin

Tributyltin compounds are a group of compounds containing the 3Sn moiety, such as tributyltin hydride or tributyltin oxide. They are the main active ingredients in certain biocides used to control a broad spectrum of organisms...

 (TBT) contamination (an anti-fouling paint for boats which affects females of the species).

Distribution

This species is can be found on a rocky substrate or reef flats in the intertidal zone

Intertidal zone

The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...

. It is distributed in the Red Sea

Red Sea

The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...

, in the Indian Ocean along Aldabra

Aldabra

Aldabra, the world's second largest coral atoll, is in the Aldabra Group of islands in the Indian Ocean that form part of the Seychelles. Uninhabited and extremely isolated, Aldabra is virtually untouched by humans, has distinctive island fauna including the Aldabra Giant Tortoise, and is...

 Atoll, Chagos, East Coast of South Africa, Transkei

Transkei

The Transkei , officially the Republic of Transkei , was a Bantustan—an area set aside for members of a specific ethnicity—and nominal parliamentary democracy in the southeastern region of South Africa...

, Natal

Natal, South Africa

Natal is a region in South Africa. It stretches between the Indian Ocean in the south and east, the Drakensberg in the west, and the Lebombo Mountains in the north. The main cities are Pietermaritzburg and Durban...

, Kenya

Kenya

Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...

, Madagascar

Madagascar

The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...

, the Mascarene Basin, Mozambique

Mozambique

Mozambique, officially the Republic of Mozambique , is a country in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west and Swaziland and South Africa to the southwest...

 and Tanzania

Tanzania

The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...

, and in the Indo-West Pacific.

External links

• Gastropods.com : Morula (Morula) granulata; accessed : 19 November 2010