Volvox carteri F.Stein 1873 is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of colonial

Coenobium

A coenobium is a colony containing a fixed number of cells, with little or no specialization. They occur in several groups of algae. The cells are often embedded in a mucilaginous matrix and may be motile or non-motile....

 green algae in the order Volvocales. V. carteri forms large spherical colonies, or coenobium, of 2000-6000 Chlamydomonas

Chlamydomonas

Chlamydomonas is a genus of green algae. They are unicellular flagellates. Chlamydomonas is used as a model organism for molecular biology, especially studies of flagellar motility and chloroplast dynamics, biogenesis, and genetics...

type cells. Colonies contain mostly somatic cell

Somatic cell

A somatic cell is any biological cell forming the body of an organism; that is, in a multicellular organism, any cell other than a gamete, germ cell, gametocyte or undifferentiated stem cell...

s plus a smaller number of gamete

Gamete

A gamete is a cell that fuses with another cell during fertilization in organisms that reproduce sexually...

s in female or male colonies. In addition to female colonies with eggs and male colonies with sperm

Sperm

The term sperm is derived from the Greek word sperma and refers to the male reproductive cells. In the types of sexual reproduction known as anisogamy and oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell...

 bundles, purely vegetative colonies exist. All three types of colonies may also have specialized cells called gonidia for asexual reproduction

Asexual reproduction

Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only, it is reproduction which does not involve meiosis, ploidy reduction, or fertilization. A more stringent definition is agamogenesis which is reproduction without...

of the colony.