Table 2.

Structural grade, gamete dimorphism, and size data for volvocine algae

Species	No. of cells	Structural grade	Gamete dimorphisma	Protoplasmic volume (μm3)	Reproductive cell volume (μm3), M	Macro‐ or isogamete volume (μm3), b	Micro‐ or isogamete volume (μm3), a	Inferred zygote volume (μm3), S	b/a
Carteria palmata	1	Unicellular	Isogamy	5,080	5,080	5,080	5,080	10,160	1
Chlamydomonas allensworthii	1	Unicellular	Anisogamy	950	950	950	59	1,010	16
Chlamydomonas chlamydogama	1	Unicellular	Isogamy	1,120	1,120	560	560	1,120	1
Chlamydomonas indica	1	Unicellular	Isogamy	733	733	183	183	367	1
Chlamydomonas microhalophila	1	Unicellular	Isogamy	1,508	1,508	754	754	1,508	1
Chlamydomonas moewusii	1	Unicellular	isogamy	8,370	8,370	2,093	2,093	4,185	1
Chlamydomonas reinhardtii	1	Unicellular	Isogamy	11,000	11,000	5,500	5,500	11,000	1
Chlamydomonas sphagnicola	1	Unicellular	Oogamy	3,591	3,591	3,591	225	3,816	16
Chlamydomonas suboogama	1	Unicellular	Anisogamy	3,054	3,054	3,054	191	3,245	16
Chlorogonium mariae	1	Unicellular	Isogamy	524	524	131	131	262	1
Chloromonas chenangoensis	1	Unicellular	Isogamy	4,009	4,009	4,009	4,009	8,018	1
Lobocharacium coloradoense	1	Unicellular	Isogamy	1,734,159	1,734,159	524	524	1,047	1
Lobochlamys segnis	1	Unicellular	Isogamy	700	700	22	22	44	1
Oogamochlamys ettlii	1	Unicellular	Oogamy	6,842	6,842	6,842	428	7,270	16
Oogamochlamys gigantea	1	Unicellular	Oogamy	8,181	8,181	8,181	128	8,309	64
Oogamochlamys zimbabwiensis	1	Unicellular	Oogamy	4,189	4,189	4,189	262	4,451	16
Pseudocarteria corcontica	1	Unicellular	Isogamy	13,360	13,360	13,360	13,360	26,719	1
Tetrabaena socialis	4	Colonial	Isogamy	11,800	2,950	738	738	1,475	1
Stephanosphaera pluvialis	8	Colonial	Isogamy	10,648	1,331	83	83	166	1
Desmotetra antarctica	16	Colonial	Isogamy	147,244	9,203	575	575	1,150	1
Desmotetra aureospora	16	Colonial	Isogamy	77,584	4,849	303	303	606	1
Gonium maiaprilis	16	colonial	Isogamy	28,272	1,767	221	221	442	1
Gonium pectorale	16	Colonial	Isogamy	75,600	4,725	2,363	2,363	4,725	1
Gonium quadratum	16	Colonial	Isogamy	11,200	700	697	697	1,394	1
Gonium viridistellatum	16	Colonial	Isogamy	28,300	1,769	884	884	1,769	1
Volvulina pringsheimii	16	Colonial	Isogamy	28,300	1,769	1,767	1,767	3,534	1
Colemanosphaera charkowiensis	32	Colonial	Anisogamy	82,318	2,572	2,572	80	2,653	32
Eudorina elegans	32	Colonial	Anisogamy/internal	232,000	7,250	3,625	57	3,682	64
Gonium multicoccum	32	Colonial	Isogamy	97,700	3,053	3,053	3,053	6,106	1
Pandorina morum	32	Colonial	Isogamy	294,000	9,188	574	574	1,148	1
Platydorina caudata	32	Colonial	Anisogamy	262,000	8,188	4,094	128	4,222	32
Volvulina steinii	32	Colonial	Isogamy	70,600	2,206	2,206	2,206	4,413	1
Pleodorina indica	64	Multicellular	Anisogamy/internal	357,000	9,200	1,150	18	1,168	64
Astrephomene gubernaculifera	128	Multicellular	Isogamy	6,100,000	48,800	3,050	3,050	6,100	1
Pleodorina japonica	128	Multicellular	Anisogamy/internal	1,040,000	14,100	14,100	110	14,210	128
Volvox pocockiae	1,500	Multicellular	Oogamy	2,650,000	113,000	113,000	1,766	114,766	64
Volvox tertius	2,000	Multicellular	Oogamy	763,000	655,000	655,000	20,469	675,469	32
Volvox carteri	3,000	Multicellular	Oogamy	1,570,000	10,300	10,300	80	10,380	128
Volvox aureus	3,200	Multicellular	Oogamy	362,000	7,230	7,230	226	7,456	32
Volvox obversus	4,000	Multicellular	Oogamy	2,090,000	38,800	38,800	303	39,103	128
Volvox africanus	6,000	Multicellular	Oogamy	963,000	47,700	47,700	373	48,073	128
Volvox capensis	20,000	Multicellular	Oogamy	42,100,000	125,000	125,000	244	125,244	512
Volvox globator	22,000	Multicellular	Oogamy	737,000	11,000	11,000	43	11,043	256
Volvox dissipatrix	31,800	Multicellular	Oogamy	133,000,000	33,500	33,500	131	33,631	256
Volvox rousseletii	50,000	Multicellular	Oogamy	105,000,000	14,100	14,100	28	14,128	512

^aAnisogamy/internal refers to anisogamy with internal fertilization.