History, Distribution and Classification of Haematococcus pluvialis
Observations of Haematococcus began in 1797 by Girod-Chantrans and were continued
by other Europeans. The first description of Haematococcus pluvialis was conducted by Flotow
in 1844, and in 1851 Braun added to the details and corrected a few errors of earlier observations.
Herrick published some brief comments in 1899 on the life history of Haematococcus, noting the
alternation of lifecycle between resting cells and motile cells.
The first extensive description of the life history of Haematococcus in English was by T.E.
Hazen in 1899 in a published report of the Torrey Botanical Club. He noted that the algae is
usually found as a blood-red crust adhering to the sides of urns or shallow pools near the ocean
which were periodically filled with water. He went on to describe the life history of the alga
through a red resting stage and green swimming stage followed again by a red resting stage. At
this time the chemical nature of the red coloring matter within the alga was unknown, but was
given the name “haematochrom”, and is now known as astaxanthin. Hazen reported that the alga
"is reported as very common and widely distributed in Europe, where it is found from Scandinavia
to Venice...the alga is distributed from Vermont to Texas and from Massachusetts to Nebraska
and probably farther West."
A few years later, Peebles (1901a, 1909b) published a life history of the alga with detailed
drawings of changes occurring in the “haematochrom” throughout the life cycle. In 1934, Elliot
added details of the cellular morphology to the life history of the alga. During the life cycle four
types of cells were distinguished: microzooids, large flagellated macrozooids, non-motile palmella
forms; and haematocysts, which are large red cells with a heavy resistant cell wall. The
macrozooids predominated in liquid cultures with sufficient nutrients, but when environmental
conditions become unfavorable the palmella stage results, followed by the resistant haematocysts
and the accumulation of astaxanthin. Subsequently, after being exposed to a nutrient-favorable
environment, haematocysts give rise to motile microzooids that grow into palmella or macrozooid
stages.
Pocock (1937 and 1961) described the distribution and life history of Haematococcus
strains isolated in Africa. Almgren (1966) described the ecology and distribution of
Haematococcus in Sweden, where the alga is found in ephemeral rain pools made of rock,
generally of small dimensions and based upon firm material, impermeable to water. Droop (1961)
also noted that that Haematococcus typically inhabited rock pools, often, though not necessarily,
within a few feet of the sea.
The widespread occurrence of Haematococcus in temporary rather than permanent bodies
of water is due, at lease in part, to the fact that such pools are usually free of other competing
algae, and not to any inherent characteristic of the pools. Haematococcus is considerably better
suited for survival under conditions of expeditious and extreme fluctuations in light, temperature
and salt concentration than most algae, due to its rapid ability to encyst (Proctor, 1957a).