Here we see Gammarus pulex, a fresh water amphipod shrimp which was collected in a net from the Grand Canal in Co. Kildare. There, it is by far the most abundant macroinvertebrate. In ecosystems such as canals and streams, they play a major role in breaking down decaying plant and animal matter.

The Gammarus pulex has long been used as a model organism in biology for the study of ecotoxicology. This shrimp, like most others are scavengers and opportunistic omnivores, feeding on algae, microbes and biofilms, decaying detritus, fungi and animal matter.

This image is a focus stacked montage with a magnification x1,000.

The body length of this segmented fresh water shrimp measures about 4mm in length. The long legs on the second half of the body are called pereopods, whereas the shorter legs on the rear half of the body are called pleopods. Unlike the eyes on true shrimp, their eyes are sessile.

The image is a focus stack panorama made using a combination of DF + Polarisation with compensation and has a magnification of around x1,000.

This is the larva of the great diving beetle (Dytiscus). It is a ferocious and cannibalistic creature that will not think twice about luring and snaring it's younger sibling for dinner. Clenched in a tight grip, it stabs it's victim with it's hypodermic-like appendages. The internal body of the victim is liquified as a cocktail of digestive enzymes runs through. Dytiscus sucks up the resulting soup.

The Chironomidae, are a family of non-biting midges, in the order Diptera. Their larvae are abundant in all freshwater habitats and are prominent bottom feeders.

The larvae, pupae and imagoes of Chironomidae are important food items in the diets of fish whilst the the imagoes are an important food for birds such as swallows and martins. Chironomidae are amongst the most ubiquitous of insects, found the world over. Chironomidae have a life cycle consisting of four stages: egg, larva, pupa, and imago.

Asellus aquaticus is a freshwater crustacean that resembles a woodlouse. This particular louse was found in the Grand Canal, Co. Kildare, but they are generally found in rivers, streams and fresh water ponds. Asellus aquaticus is a key indicator of water quality.

With a short life span and reasonably simple genetics, Drosophila melanogaster is extensively used as a model organism in research laboratories world wide. Throughout the summer months, D. melanogaster is a pest in the home where it feeds on fruit and meats.

Very large focus stacked montage captured in dark field + polarised light with compensation.

The water boatman, also known as Corixidae, is an aquatic insect that is found in freshwater environments such as ponds, lakes, and slow-moving streams. They are relatively small, usually only about 1-2 centimeters in length, and are oval-shaped with flat bodies. Water boatmen are known for their unique swimming behaviour, which involves rowing their long legs back and forth in a synchronized motion, similar to the way a rower moves a boat through the water. This movement creates tiny waves on the surface of the water, allowing the insect to propel itself along.

Water boatmen feed on a variety of small aquatic animals, including insects, crustaceans, and even small fish. They use their sharp, pointed mouthparts to pierce the skin of their prey and suck out their bodily fluids. Water boatmen are also known for their ability to produce sound. Males produce a series of high-pitched chirps or clicks by rubbing their front wings together. The sound is used to attract mates and defend territory.

Seen here through crossed polarisers, this is the nymph (aquatic larval stage) of the Damselfly, an insect in the order Odonata. The nymph of the Damselfly lives its life in the fresh water pond. Damselfly nymphs have long, slender bodies and are typically about 1-2 centimeters in length. They have large, bulging eyes and three pairs of legs, which are modified for grasping prey. At the end of their bodies, they have three appendages, known as caudal gills, which help them extract oxygen from the water.

Damselfly nymphs are active predators and feed on a variety of small aquatic animals, including insect larvae, crustaceans, and small fish. They use their modified legs to grab and hold onto their prey, and their strong jaws to crush and consume it. As they develop, damselfly nymphs undergo a series of molts, shedding their exoskeleton as they grow. After several molts, they reach their final larval stage, where they are ready to emerge from the water and transform into an adult damselfly.

The order Diptera contains family of True Flies which include the Chironomidae - the midge flies. This is the larval stage of the midge fly which can be found munching on the detritus matter on the bed of the pond. These larvae along with other creatures, help to decompose plant and animal matter, releasing nutrients back into the soil and the cycle of life.

Chironomidae larvae are filter feeders and typically feed on algae and small organic particles in the water. They have a unique breathing system that involves a series of tube-like structures, known as "tracheae", which allow them to extract oxygen from the water. The tracheae are often visible as small, branching tubes that extend from the larva's body.

Chironomidae larva, also known as midge larva, are aquatic insects in the family Chironomidae, and they are found in freshwater environments such as lakes, ponds, and streams. They are a common and important part of many freshwater ecosystems, and are an important food source for fish and other aquatic animals

Chironomidae larvae play an important role in freshwater ecosystems as both prey and decomposers. They are an important food source for many fish and other aquatic animals, and their bodies also provide important nutrients for decomposer organisms when they die.

A sample of algae was collected from the soft flowing Lugduff river that passes through Glendalough. Rummaging among the alage filaments was this larva.

Caddisfly larvae are aquatic insects in the order Trichoptera. They are found in freshwater environments such as rivers, streams, and ponds. Caddisflies are known for their ability to create protective cases for their larval stage out of various materials such as twigs, pebbles, sand, and even pieces of aquatic plants like seen here.

A gelatinous cocoon containing numerous embyro's.

A gelatinous cocoon containing numerous embyro's.

A gelatinous cocoon containing numerous embyro's.

A gelatinous cocoon containing numerous embyro's.

Here we see the larva of the species of phantom midge Chaoboridae. The image is a focus stack montage made in darkfield compensated polarised light microscopy. The muscle bundles appear to glow in various colours. Bundles whose longitudinal axis are aligned appear to glow in the same colour. The colours are dependent upon the orientation with respect to the optic axis and the fiber density constituting the bundles. The bundles appear to glow because they exhibit to property of birefringence.

The phantom midge larva, also known as the glassworm, is the aquatic larval stage of the phantom midge (Chaoborus spp.), a type of non-biting midge in the family Chaoboridae. These larvae are found in freshwater environments, such as lakes, ponds, and slow-moving rivers.

Water fleas belong to the order Cladocera classified in the anthropod taxon Crustacea. The are most likely called fleas because they appear to hop through the water. They are found in a wide variety of freshwater environments, including lakes, ponds, rivers, and streams, and play an important role in the ecology of these systems.

This is a water flea to be afraid of, that is if you were another water flea! Polyphemus pediculus is a carnivore that preys upon small animals, mostly other water fleas. It uses it's feet for grabbing onto other fleas. Like other water fleas, it uses it's antenna for locomotion through the water. It has a distinctive elongated tail spine. The stomach contents appear as brown matter.

Magnified over 600 times and captured in DIC, we can look into the head region of the nematode worm.

Large colony of the bell shaped ciliate - Peritrich. The entire colony is attached by a single long slender stalk to the organic debris below. Peritrich are holozoic ciliates. This means that they have a mouth and acquire nutrients by engulfing solid organic matter. Their mouth consists of an elaborate food-catching apparatus that secures food by means of ciliary currents. The anterior end of each peritrich body forms a bulging peristome. The peristome is the blue coloured path seen in each cell and is defined as a fringe of small projections around the mouth of a capsule. In this case, the fringe is composed of cilia, all of which beat in synchronised motion, like a Mexican-wave. The motion induces a water currents in the local environment in the form of a vortex that causes food particles to spiral down the funnel where they are then guided into the vestibule along the adornal zone.

Close-up of a large colony of the bell shaped ciliate - peritrich. The colony mirrors the structure of a tree in that it has a trunk called a stalk made up of myonemes. The stalk breaks up into a series of branches at the end of each is the bell-shaped peritrich capsule.

The blue coloured path is the peristome, the structure that generates the beautiful instability in the local watery environment, the vortex that funnels food into its mouth.

A small colony of Peritrich imaged in differential interference contrast.

Here we can see the details of the Peritrich as we peer inside of its translucent body as imaged in differential interference contrast microscopy and magnified over 600 times.

A rotifer hunts for food among a large colony of vorticella.

The green dots seen inside are its endosymbioants, Zoochlorella. Zoochlorella are alga cells which contain chloroplasts. The chloroplasts provde the flatworm with energy and the flatworm provides the zoochlorella with a safe and secure home.

Photographed here swimming through its aquatic environment in the hunt for food, Typhloplana viridata is a species of flatworm that is found in fresh water habitats. The green cells living symbiotically inside the worm are the single-celled green algae - zoochlorellae. A nutritious meal is made up of carbon dioxide, organic matter rich in nitrogen and phosphorous, exuding oxygen and other minerals as waste products that the worm devours. Captured with Olympus X Line 40x objective on the Olympus BX51 Microscope.

The green dots seen inside are its endosymbioants, Zoochlorella. Zoochlorella are alga cells which contain chloroplasts. The chloroplasts provde the Paramecium with energy and the Parameciumreturns the favour by providing the zoochlorella with a safe and secure home.

Belonging to the kingdom Protista, Paramecium are agile creatures whose hydrodynamic propulsion in the low Reynolds number regime is achieved by rapid synchronised beating of the thousands of cilia carpeting its outer body.

Here, a Paramecium bursaria glides along a filament of alga hoovering bacteria that populate the encapsulating biofilm.

The intake of food is achieved by the beating cilia lining its oral groove, which induce a circular rotating vortex in the surrounding local environment and thereby funnel small debris into its mouth. The food particles are stored in membrane bound compartments called vacuoles which breakdown the food through chemical reactions catalysed by enzymes.

Paramecium feed on the biofilm encapsulating a strand of filamentous Spirogyra algae. The cell nuclei and cytoskeletal network are visible in the filamentous algal cells. The globular spots on the cytoskeletal filaments are motor proteins which ‘run’ along these microtubule ‘highways’. The green structures are the chloroplasts which are helically wound within the interior of the cells and produce sugary food and oxygen as a waste product through photosynthesis.