Botanic Gardens Trust, Sydney, Australia

Spores/Sporangia

Marine algal spores come in many shapes and sizes. All spores contain all the necessary genetic information to germinate and grow into the next or new generation of plants. Gametes, on the other hand, always need to be fertilised by their sexual counterpart (either male or female) before they can grow into an adult plant.

Red algal tetrasporangia come in three basic designs. Cruciate, whereby the four spores form a cross, Tetrahedral, where they form the corners of a three sided pyramid, and Zonate, where they are placed end to end in a row. 

 

   

Anotrichium tetraspores

 

Red algal spores that are the result of the fertilisation of the male and female gametes are known as carposporangia meaning ‘fruit spores‘. Here you can see the spores forming a tight ball perched on a very thin, transparent ‘connecting filament‘ in Schmitzia evanescens.

gonimoblast

 

Red algal spores that are the result of the fertilisation of the male and female gametes are known as carposporangia meaning ‘fruit spores‘. Here you can see the spores forming a tight ball perched on a very thin, transparent ‘connecting filament‘ in Schmitzia evanescens.

Tomaculopsis

 

In many brown algae, such as this specimen of Tomaculopsis herbertiana, you can see the sporangial sori forming swellings along the stalks of the ‘pom poms‘.

Sporochnus stylosus

 

In Sporochnus stylosus, another brown alga, the sporangial sori form swellings at the base of the lateral branchlets.