The mollusks of the Peruvian sea demonstrate the prevailing biodiversity in that region of South America. This is known as the Mar de Grau, in honor of the hero of the Peruvian Navy, and has about 300 kilometers of tropical beaches and a coastline of about 2,300 kilometers long.
In terms of its fish production, it is the third in the world, and ranks first in biological diversity. The particular characteristics of this sea promote the existence of significant amounts of plankton and phytoplankton.
More than thirty species of mammals, 700 species of fish and a great variety of crustaceans inhabit it. In this sea the presence of a little more than a thousand species of mollusks has been reported.
Main mollusks of the Peruvian sea
Gastropods
Gastropods belong to the Gastropoda class, which is the largest group of mollusks.
The class is made up of snails and slugs. The former have a shell into which the animal can retract, while the shells of the latter have been reduced to an internal fragment or have been completely lost in the course of evolution.
In the Peruvian sea, the Gastropoda class represents 55.99% of the total population of mollusks. Among the most abundant families are: Muricidae, Collumbellidae, Trochidae, Naticidae, Buccinidae, Fissurellidae, Olividae, Crepidulidae, Turridae and Cancellarida.
Bivalvia
The second type of mollusks in the Sea of Grau is the Bivalvia class with a representation of 36.35%.
The outer covering of these is a two-part hinged shell that contains an invertebrate soft body. This is the case, for example, of clams, oysters, mussels and scallops. Bivalve mollusks breathe through their gills that act as a filter, collecting food.
Some have a kind of retractable claw that allows them to move or dig.
Of the 54 families of bivalves found in the Peruvian sea, the Veneridae with 57 species and the Tellinidae with 37 stand out. The group is completed by Arcidae, Mytilidae, Semelidae, Pectinidae, Mactridae, Donacidae, Psammobiidae, Corbulidae and others.
Cephalopods
The largest invertebrates on earth are found in the group of cephalopods. Their nervous system is more developed than that of other mollusks.
They do not have any type of skeleton and their body is divided into a head, a visceral sac (protected by a mantle or pallium) and a foot.
The most developed cephalopods are octopuses. These predators have eight arms instead of ten like other squids and exhibit highly developed behavior patterns.
With 3.34%, its representation in the Peruvian sea is lower. And they are dominated by the Ommastrephidae family.
Polyplacophores
This group of organisms has eight valves in their shells. They are all sailors and around the world.
Most live in the rocky intertidal zone or just below low tide, but some live in deep water over 7000 meters. Some species are associated with algae and marine plants.
In the Sea of Grau, there are five species of polyplacophores, specifically of the Ischnochitonidae family.
References
- Ramírez, R., Paredes, C. and Arenas, J. (2003). Mollusks of Peru. Journal of Tropical Biology, Vol. 51, No 3, pp. 225-284.
- The Sea (2015). Embassy of Peru. Recovered from embassyperuindia.in.
- Herrera Cuntti, A. (2006). Historical ramblings on the web, Book 1. Chincha: AHC Ediciones Peru.
- Gastropod. (2016, August 24). Encyclopædia Britannica. Recovered from britannica.com
- What is a bivalve mollusk? (2017). National Ocean Service. NOAA, Department of Commerce. Recovered from oceanservice.noaa.gov.
- Cephalopods. (s / f). The living world od molluscs. Recovered from demolluscs.at.
- Bunje, P. (2003). The Polyplacophora. Chitons, the eight-shelled molluscs. Recovered from ucmp.berkeley.edu.