Oct. 23, 2012 --

For 37 years the Nikon Small World photography competition showcases the beauty and extreme details captured using light microscopes. Every year the world below the waves provides many interesting subjects for the Small World competition. Most examples of aquatic life are entered by professionals in, or students of marine biology, but many of these images were provided by entrants from other disciplines who simply find marine life fascinating. Here, photomicrographer Arlene Wechezak of Anacortes, Wash., and 10th place winner of the 2009 Small World Contest, magnified 10x an Obelia species of hydrozoa with extruded medusae as a fresh sea water mount using a darkfield.

Here we see the same species as before only this time magnified 40x its original size. The extruded medusae of the Obelia hydrozoa contain tentacles that sting and capture the animal's prey.

In this image, biologists magnified 20x a species of bryozoan of the genus Membranipora found on seaweed and kelp using stereomicroscopy.

Almost transparent tissue covers the hard skeleton "cups" of each polyp in this brightfield photo of brain coral in the genus Goniastrea magnified 25x.

Marine biologist Alvaro Migotto of the University of São Paulo in Brazil used stereomicroscopy and a darkfield to capture this photo of a brittle star magnified 8x.

Photographer David Maitland of Feltwell, UK, zoomed in with 100x magnification on coral sand over a brightfield.

Surface of shark skin tanned with a chromium compound magnified 40x with reflected light.

ANALYSIS: US Shark Fin Soup Appalling and Widespread

On its side this marine ciliate (Rhabdonella spiralis)looks like a trumpet; when the image is turned vertical it looks like a champagne flute - a fine photo from French oceanographer John Dolan, who used a differential interference contrast technique and 40x magnification.

A freshwater Bryozoan, or moss animal, Cristatella mucedo in a darkfield magnified 6.5x.

BIG PIC: Rock Vomit: A Sea Squirt Infestation

Biologist Diana Lipscomb of George Washington University in Washington, used Nomarski Interference Contrast and a magnification of 400x the original size to showcase a suctorian ciliate, Acineta tuberosa, in the phylum Ciliophora.

Using Nomarski Interference Contrast and a magnification of 400x the original size this photo shows a ciliate in the genus Sonderia that preys upon various algae, diatoms, and cyanobacteria.

PHOTOS: Evolution Before Your Eyes

Algae magnified 400x using a confocal technique. (Algae genus: Staurastrum, Kirchneriella, Akistrodesmus and Microthamnion)

PHOTOS: Small Worlds Never Before Seen