Bosmina longirostris are known to thrive in ponds and lakes. They are not considered to require conservation efforts, and have not been evaluated by the IUCN Red List program.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
Bosmina longirostris is preyed upon many different invertebrate predators, such as Chaoborus, cyclopoid copepods, Mysis relicta, Leptodora kindtii, Epischura lacustris, Limnocalanus macrurus, and Senecella calanoides. They are also an important primary food source for planktivorous fish, including young whitefish (Coregonus clupeaformis).
During daylight these animals sometimes form dense aggregations, as many as 9000 individuals per liter of water. These groups often significantly reduce the food supply in their location but stay together anyway until night. Because they only group together in daylight, and do so even when this reduces food availability, it is believed that this behavior is predator avoidance, possibly a "Selfish Herd" phenomenon.
Known Predators:
These animals are called water fleas because their physical appearance and movements resemble those of land fleas. This common name also applies to 620 different species. The members of B. longirostris are sexually dimorphic; females have large antennules that curve back over the head which are absent in males. Females range in size from 0.4 to 0.6 mm long, while males range from 0.4 to 0.5 mm long. Both sexes have a mucro, a sharp point attached on their head which varies in length by location. The function of mucro in B. longirostris is unknown. However, the mucro serves to distinguish B. longirostris from their very close relative, Eubosmina sp., which lack this structure. They also have a carapace, which looks like a folded shell that covers the animal and opens on both the ventral and posterior sides. The length of both mucro and carapace vary in season, decreasing in the summer due to increased predation risk with size.
Water fleas are ectothermic.
Range length: 0.4 to 0.6 mm.
Other Physical Features: ectothermic ; bilateral symmetry
Sexual Dimorphism: female larger; sexes shaped differently
Bosmina longirostris generally live little more than 20 days; however, when food is scarce, they may live up to only 10 days.
Typical lifespan
Status: wild: 10 (low) days.
Average lifespan
Status: wild: 20 days.
Bosmina longirostris are commonly found in ponds and lakes. They are also found in the littoral zones of temperate and tropical bog lakes.
Close relatives of B. longirostris can live in waters with weak currents, and are often found near the surface of the water, where the concentration of algae, their food source, is highest.
Habitat Regions: temperate ; tropical ; freshwater
Aquatic Biomes: lakes and ponds
Wetlands: marsh ; swamp ; bog
Other Habitat Features: intertidal or littoral
Bosmina longirostris is one of the 620 species that are commonly called water fleas. Bosmina longirostris is found in freshwater lakes and ponds throughout the world in temperate and tropical climates including Nearctic, Palearctic, Neotropical and Ethiopian regions. These regions include parts of Africa, Europe and the United States.
Biogeographic Regions: nearctic ; palearctic ; ethiopian ; neotropical
Bosmina longirostris are mainly filter feeders. They eat protozoa, diatoms, and other alge ranging in size from 10 to 15 µm. They prey on Cyclotella, Microcystis, and Chlorella. Filter-feeding is achieved by five pairs of thoracic limbs that are developed for grasping food particles. Large particles can be grasped by the first three thoracic limbs, while the fourth and fifth pairs filter small particles. The first two pairs of thoracic limbs can be used to push the food inside the food groove, while the third to fifth pairs act as filter. In this filter mechanism, small food particles are collected and pushed into the food groove. The feeding system of Bosmina sp. is more efficient in low food densities. The filter structure of other members of the genus Bosmina. is known to be poorly developed, and they are generally less efficient filter feeders than Daphnia sp. They are generally not selective feeders; however, when they have to compete with Daphnia species they switch their preferences.
Plant Foods: algae; phytoplankton
Other Foods: microbes
Foraging Behavior: filter-feeding
Primary Diet: herbivore (Algivore); planktivore
Bosmina longirostris compete with closely related species for food. They are algivores, and serve as first consumers. Also, along with other zooplankton, B. longirostris are preyed upon by fishes. They are important zooplankton species linking bacteria and algae to higher trophic levels.
There is no direct positive importance for humans. However, B. longirostris play important role in the food web as they are a good source of food for many aquatic organisms. Also, because they filter-feed on algae, they can improve water clarity.
Too many B. longirostris concentrated in one area can reduce the oxygen level in the water, which can have a negative impact on fishes.
Immediately after hatching, body length is approximately 0.21 mm. When food is scarce, B. longirostris stop growing after maturation and use all of their energy for reproduction. If food concentration is high, they will continue to grow after sexual maturation. Reaching maturation takes between 3.14 to 5.83 days from birth. The length of the carapace grows from their birth to 20 days; however their rate of growth decreases with age.
When females lay eggs, they hatch to become juveniles. They are considered adults once they are larger than the smallest egg carrying female.
There is little information available on the communication and perception of B. longirostris; however, its closely related species, Daphnia sp. communicate using chemical signals, and have one black compound eye that detects light.
Communication Channels: visual ; chemical
Perception Channels: visual ; chemical
There are three different types of mating systems that B. longirostris use to reproduce: Sexual reproduction, cyclical parthenogenesis and obligate parthenogenesis. Bosmina longirostris are polygynandrous, so both males and females have multiple mates.
Mating System: polygynandrous (promiscuous)
Reproduction of B. longirostris is highly dependent on the environment. When B. longirostris go through parthenogenesis, a form of asexual reproduction, they produce the same gender that of the parent, however there is little information available about parthenogenesis of B. longirostris. Studies of Bosmina in temperate regions have shown they reproduce by using facultative parthenogenesis, allowing them to reproduce sexually or by parthenogenesis; wheras other Bosmina sp. in arctic lakes reproduce using obligate parthenogenesis, meaning they can only reproduce asexually. Bosmina longirostris breed throughout the year but are more active from May to June and August to September when algae grows more rapidly. Their reproductive rates are dependent upon how much food is available.
Female B. longirostris are known as sexually mature when they first have eggs in their brood pouch. This species matures faster if more food is available. Varying food concentrations can also cause differences in the number of eggs produced; if more food is available, they produce more eggs (up to four eggs at a time). During their life span, females typically lay anywhere from 1 to 11 eggs.
Breeding interval: Once they are mature (3 to 5 days after birth), they can breed up to 4 times throughout their 20 days or so of life span.
Breeding season: highest from May to June and August to September
Range number of offspring: 1 to 11.
Range age at sexual or reproductive maturity (female): 3.14 to 5.83 days.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); parthenogenic ; sexual ; asexual ; oviparous
Female B. longirostris carry the eggs (up to two eggs) in their brood pouch until the eggs hatch and become free living and independent.
Parental Investment: pre-hatching/birth (Provisioning: Female, Protecting: Female)
Bosmina longirostris is a species of water flea found in the Great Lakes and Central Europe. It is found in the plankton near the shoreline of lakes and ponds.[2]
Bosmina longirostris has multiple morphotypes. The most common morphotypes in freshwater are cornuta, pellucida, similis, and typica. The morphotypes refer to the size and curve of the antennules of the organism, as well as the size of the mucrones.[3]
Bosmina longirostris is a species of water flea found in the Great Lakes and Central Europe. It is found in the plankton near the shoreline of lakes and ponds.
