A gill is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia is the zoologists' name for gills.
Hemiptera is an order of insects, commonly called true bugs, comprising over 80,000 species within groups such as the cicadas, aphids, planthoppers, leafhoppers, assassin bugs, bed bugs, and shield bugs. They range in size from 1 mm (0.04 in) to around 15 cm (6 in), and share a common arrangement of piercing-sucking mouthparts. The name "true bugs" is often limited to the suborder Heteroptera.
Aquatic respiration is the process whereby an aquatic organism exchanges respiratory gases with water, obtaining oxygen from oxygen dissolved in water and excreting carbon dioxide and some other metabolic waste products into the water.
Aquatic insects or water insects live some portion of their life cycle in the water. They feed in the same ways as other insects. Some diving insects, such as predatory diving beetles, can hunt for food underwater where land-living insects cannot compete.
The diving bell spider or water spider is the only species of spider known to live almost entirely under water. It is the only member of the genus Argyroneta. When out of the water, the spider ranges in colour from mid to dark brown, although the hairs on the abdomen give it a dark grey, velvet-like appearance. It is native to freshwater habitats in Europe and Asia.
The Gerridae are a family of insects in the order Hemiptera, commonly known as water striders, water skeeters, water scooters, water bugs, pond skaters, water skippers, water gliders, water skimmers or puddle flies. Consistent with the classification of the Gerridae as true bugs, gerrids have mouthparts evolved for piercing and sucking, and distinguish themselves by having the unusual ability to walk on water, making them pleuston (surface-living) animals. They are anatomically built to transfer their weight to be able to run on top of the water's surface. As a result, one could likely find water striders present in any pond, river, or lake. Over 1,700 species of gerrids have been described, 10% of them being marine.
Corixidae is a family of aquatic insects in the order Hemiptera. They are found worldwide in virtually any freshwater habitat and a few species live in saline water. There are about 500 known species worldwide, in 55 genera, including the genus Sigara.
Veliidae is a family of gregarious predatory insects in the suborder Heteroptera. They are commonly known as riffle bugs, small water striders, or broad-shouldered water striders because the segment immediately behind the head is wider than the rest of the abdomen. Species of the genus Rhagovelia are also referred to as ripple bugs.
Notonectidae is a cosmopolitan family of aquatic insects in the order Hemiptera, commonly called backswimmers because they swim "upside down" (inverted). They are all predators and typically range from 0.5 to 1.5 cm (0.2–0.6 in) in length. They are similar in appearance to Corixidae, but can be separated by differences in their dorsal-ventral coloration, front legs, and predatory behavior. Their dorsum is convex, lightly colored without cross striations. Their front tarsi are not scoop-shaped and their hind legs are fringed for swimming. There are about 350 species in two subfamilies: Notonectinae with seven genera, and Anisopinae with four genera. Members in the former subfamily are often larger than those in the latter.
Nepomorpha is an infraorder of insects in the "true bug" order (Hemiptera). They belong to the "typical" bugs of the suborder Heteroptera. Due to their aquatic habits, these animals are known as true water bugs. They occur all over the world outside the polar regions, with about 2,000 species altogether. The Nepomorpha can be distinguished from related Heteroptera by their missing or vestigial ocelli. Also, as referred to by the obsolete name Cryptocerata, their antennae are reduced, with weak muscles, and usually carried tucked against the head.
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa, trochanter, femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus, patella.
Notonecta glauca is a species of aquatic insect, and a type of backswimmer. This species is found in large parts of Europe, North Africa, and east through Asia to Siberia and China. In much of its range it is the most common backswimmer species. It is also the most widespread and abundant of the four British backswimmers. Notonecta glauca are Hemiptera predators, that are approximately 13–16 mm in length. Females have a larger body size compared to males. These water insects swim and rest on their back and are found under the water surface. Notonecta glauca supports itself under the water surface by using their front legs and mid legs and the back end of its abdomen and rest them on the water surface; They are able to stay under the water surface by water tension, also known as the air-water interface. They use the hind legs as oars; these legs are fringed with hair and, when at rest, are extended laterally like a pair of sculls in a boat. Notonecta glauca will either wait for its prey to pass by or will swim and actively hunt its prey. When the weather is warm, usually in the late summer and autumn, they will fly between ponds. Notonecta glauca reproduce in the spring.
Pleidae, the pygmy backswimmers, is a family of aquatic insects in the order Hemiptera. There are 37 species in three genera, distributed across most of the world, except the polar regions and remote oceanic islands.
Chironomus plumosus, also known as the buzzer midge, is a species of nonbiting midge (Chironomidae) that occurs throughout areas in the Northern Hemisphere.
Micronecta scholtzi, the lesser water boatman, is a species of pygmy water boatman in the family Micronectidae. It was first described by Franz Xaver Fieber in 1860. They are some 2 mm long and are common in freshwater ponds and lakes across Europe, preferring stagnant to moderately moving water. In Central Europe, the genus Micronecta is represented by five species, as follows:
Water boatman as a type of aquatic insect can mean:
Surface wave detection by animals is the process by which animals, such as surface-feeding fish are able to sense and localize prey and other objects on the surface of a body of water by analyzing features of the ripples generated by objects' movement at the surface. Features analyzed include waveform properties such as frequency, change in frequency, and amplitude, and the curvature of the wavefront. A number of different species are proficient in surface wave detection, including some aquatic insects and toads, though most research is done on the topminnow/surface killifish Aplocheilus lineatus. The fish and other animals with this ability spend large amounts of time near the water surface, some just to feed and others their entire lives.
Notonecta maculata is a backswimmer of the family Notonectidae, found in Europe, including the United Kingdom.
Notonecta undulata, also known by the common name grousewinged backswimmer, are from the family Notonectidae and the insect suborder Heteroptera. They are a type of hemipteran or true bug. These aquatic insects typically spend their time at the water's surface, using their abdomen and legs to cling to the underside of the surface tension. The Grousewinged backswimmer can be found in both lotic and lentic environments; however, they typically prefer small ponds and lakes where the water is slow-moving with less current. They swim upside down looking for prey. Once they stop swimming they float back up to the surface. These insects can be distinguished from water boatman or Corixidae by their segmented beak and front legs. Water boatman have highly modified front legs whereas backswimmers do not. Backswimmers are distributed across a broad range throughout North America. However, the species Notonecta undulata has only been documented and studied in southern Manitoba, Saskatchewan, Alberta and the western United States. N. undulata differs from other backswimmers by their antennae and size. They are approximately 10–12 mm long, and their antennae are 4 segmented.
