Echiniscoides sigismundi

Geographic Range

Echiniscodies sigismundi individuals are found in aquatic environments. They have very high species richness, though populations tend to be rather small. Populations are mostly present in the Mediterranean Sea, but also have populations located in the Arctic Ocean, the Caribbean, the North Atlantic Ocean, and the South Pacific Ocean. There are several different subspecies that scientists are debating elevating to the species level which is making it more difficult to find the geographic range of these tardigrades.

• Biogeographic Regions
• oceanic islands oceanic islands
• arctic ocean arctic ocean
• indian ocean
• atlantic ocean atlantic ocean
• pacific ocean pacific ocean
• mediterranean sea

Habitat

Echiniscodies sigismundi individuals are typically found in intertidal barnacles and seaweeds. Water bears need to stay close to water, otherwise they will dry out, so they have also been found living on moss or lichen, but those are less common examples. They live close to the surface, typically from 0-10 meters of depth. This tardigrade lives in salty environments with a PSU scale of 30-35 and temperatures ranging from 0-20, however, many have been seen expanding past this typical view.

• Habitat Regions
• saltwater or marine saltwater or marine

• Aquatic Biomes
• pelagic pelagic
• reef reef
• coastal coastal
• abyssal abyssal

• Other Habitat Features
• intertidal or littoral intertidal or littoral

Physical Description

Echiniscoides sigismundi individuals are microscopic organisms with 8 legs and a mouth on the center of their face. They are translucent and only the females develop eyes. They are cylindrical and each leg can have a range of 7-13 claws, with the fourth pair of legs having one claw less than the others.

• Other Physical Features
• endothermic endothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• female larger
• sexes shaped differently

Development

Females will lay 30 eggs on average per ovulation. Once laid, the eggs will take roughly 40 days to hatch. Echiniscodies sigismundi individuals experience ecdysis and incomplete metamorphosis, and can perform this up to 4 times during their lifetime.

• Development - Life Cycle
• metamorphosis metamorphosis

Reproduction

Not much is known about the mating systems of Echiniscoides sigismundi individuals. Some other species of tardigrade have both polyandrous and polygynous mating systems, sometimes even in the same population, but more research needs to be done to see if this is replicated in E. sigismundi .

• Mating System
• polyandrous polyandrous
• polygynous polygynous
• polygynandrous (promiscuous) polygynandrous (promiscuous)

Echiniscoides sigismundi individuals breed during the fall and winter seasons and roughly produce 30 offspring in that time frame. Eggs hatch 40 days after being laid on average. They are able to reproduce asexually through parthenogenesis. Females also have a structure that allows them to grab sperm out of the male through insertion.

• Key Reproductive Features
• seasonal breeding seasonal breeding
• parthenogenic parthenogenic
• sexual sexual
• asexual asexual
• fertilization fertilization
  • internal internal

Not much is known about the parental investment of Echiniscoides sigismundi . However, most species of tardigrades do not show any form of parental investment, so it is likely Echiniscoides sigismundi also do not show any.

• Parental Investment
• no parental involvement

Lifespan/Longevity

In most cases, Echiniscodies sigismundi individuals will live around a few months to 2 years. However, when they enter cryptobiosis, E. sigismundi individuals can last decades without food or water.

Behavior

The main behavioral pattern Echiniscoides sigismundi individuals are known for, as well as all other species of tardigrade, is cryptobiosis. This defines when a creature enters a state of inactivity due to environmental stressors. E. sigismundi individuals will perform this by curling up into a ball. In this state, E sigismundi individuals has been shown to survive in extreme hot and cold, UV radiation, being frozen, the vacuum of space, and more. E. sigismundi have been recorded to be in this state for over 30 years without needing any additional food or water. The name tardigrade also means "slow walker", first described in 1776.

• Key Behaviors
• motile motile
• sedentary sedentary
• solitary solitary

Home Range

Most of the life of an Echiniscoides sigismundi is suspected to be spent on the barnacle or seaweed where they are first born due to its slow speed and environmental needs, though more research is needed to be done to confirm this.

Communication and Perception

The specific method of communication for Echiniscoides sigismundi individuals is currently unknown. Female E. sigismundi individuals will develop large black eyes that now comprise a single pigment cup cells and one or two microvillous sensory cells.

• Communication Channels
• visual visual
• tactile tactile

• Perception Channels
• visual visual

Food Habits

Echiniscoides sigismundi individuals are omnivorous predators, having to go out and hunt food for themselves. Because of their slow disposition, their most common food source tends to be algae, but they will also eat certain species of rotifers, nematodes, fungi, cyanobacteria, and even smaller tardigrades. E. sigismundi individuals have a pair of stylets that form essentially a straw where they are able to suck out the cell contents of their prey.

• Primary Diet
• carnivore carnivore
  • vermivore
  • eats other marine invertebrates
• herbivore herbivore
  • algivore
• omnivore omnivore
• mycophage mycophage

• Animal Foods
• aquatic or marine worms
• other marine invertebrates

• Plant Foods
• algae

• Other Foods
• fungus
• microbes

Predation

No predatory defenses are currently known for Echiniscoides sigismundi . Some related species have flat proteins that resemble glass known as the Tardigrade Disordered Protein (TDP) which has been used to stop predators, but more research needs to be done to see if this protein exists in E. sigismundi . Predators for E. sigismundi include nematodes and larger tardigrades.

Ecosystem Roles

Because of the patchiness of their populations, there is not enough information to find out a lot about Echiniscoides sigismundi’s role in the ecosystem. They do tend to be predators of a lot of species in their habitat, but that can vary depending on location. There have been a few instances of commensal or parasitic relationships with adult barnacles, but the exact relationship is unknown.

Economic Importance for Humans: Positive

Echiniscoides sigismundi have had nearly no impact on the human population. However, the cryptobiosis observed in them has sparked interest in the medical community, specifically provoking research into the preservation of cells and organs.

• Positive Impacts
• source of medicine or drug source of medicine or drug
• research and education

Economic Importance for Humans: Negative

Currently there are no known negative impacts on humans due to Echiniscoides sigismundi .

Conservation Status

There are no special conservation measures put in place for Echiniscoides sigismundi .

Additional Links

Encyclopedia of Life

Contributors

Killian Garnand (author), Colorado State University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

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