| Reported in | Status | Registered by | ||
|---|---|---|---|---|
| Aphanizomenon | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Aphanizomenon flosaquae T | ||||
| Aphanizomenon gracile | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Aphanocapsa | ||||
| Aphanocapsa parietina T | ||||
| Aphanothecaceae | Unknown | Valid (ICNafp) | Excubia bot over 4 years ago | |
| Aphanothece | ||||
| Aphanothece luteola | ||||
| Aphanothece microscopica T | ||||
| Aphanothece variabilis | ||||
| Argonema | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Argonema antarcticum | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Argonema galeatum T | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Arizonema | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Arizonema commune T | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Arthrospira | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Arthrospira jenneri T | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Arthrospira massartii | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Arthrospira platensis | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Asterocapsa | ||||
| Asterocapsa gloeotheceformis T | ||||
| Atlanticothrix | Unknown | Valid (ICNafp) | Excubia bot over 4 years ago | |
| Atlanticothrix silvestris T | Unknown | Valid (ICNafp) | Excubia bot over 4 years ago | |
| Aulosira | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Aulosira bohemensis | ||||
| Aulosira fertilissima | ||||
| Aulosira laxa T | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Aulosira pseudoramosa | ||||
| Aulosira terrestris | Unknown | Valid (ICNafp) | Excubia bot over 2 years ago | |
| Azorothrix |