My Halophilic Housemates

Sharing my flat with me are these wonderful creatures.

Although not crabs these tiny creatures are still Crustaceans, being members of the Class Branchiopoda, Order Anostraca, and are commonly known as fairy or brine shrimps (as well as being sold in shops as Sea Monkeys).

These animals are adapted to live in temporary freshwater pools that dry up or freeze soon after their formation.

Their eggs have a remarkable resistance to desiccation and extremes of temperature, remaining viable for long periods when the habitat is dry.

However after rain, the resulting pools rapidly come to life with hatching naupilus larvae which develop quickly. Mature egg carrying females may be present within a few weeks.

Under favourable conditions there can be a rapid build up of the population.

Typical habitats are temporary pools in field hollows and woodlands.

In Britain the fairy shrimp, Chirocephalus diaphanus, may be found in puddles and pools created by tank ruts on Salisbury Plain.

Artemia salina can live in salt solutions ranging from 10g/l up to 220g/l.

(Sea water contains 35g/l)

The slight pink colour in their bodies is due to the red blood pigment, haemoglobin, which aids the removal of oxygen from water where its concentration is reduced by the high salt concentration and warm temperatures.

The presence of haemoglobin is unusual as the majority of crustaceans have the copper containing blood pigment,  haemocyanin.

Males can be distinguished by their large and greatly modified second antennae which they use to grasp the female during copulation.

In the above photo, it is possible to make out the modified antennae of the male, just below the eyes.

These tiny animals are constantly in motion. The graceful undulations of their limbs which allow them to swim also produce a current of water, bringing food to the mouth and oxygen to the tissues.

The pictures and video were taken using an Intel Play QX3 Computer Microscope.