| [121] Capnopsis schilleri | Appellations de Taxon | 121 |
| [1210] Riccia fluitans | Appellations de Taxon | 1210 |
| [12100] Cyclostephanos numataensis | Appellations de Taxon | 12100 |
| [12101] Cyclotella polymorpha | Appellations de Taxon | 12101 |
| [12102] Coscinodiscus perforatus var. pavillardi | Appellations de Taxon | 12102 |
| [12103] Cymbopleura palpebralis | Appellations de Taxon | 12103 |
| [12104] Cymbella peraspera var. colombiana | Appellations de Taxon | 12104 |
| [12105] Caloneis perlepida | Appellations de Taxon | 12105 |
| [12106] Cymbella praerupta | Appellations de Taxon | 12106 |
| [12107] Cymbella proxima var. proxima | Appellations de Taxon | 12107 |
| [12108] Cocconeis pseudograta | Appellations de Taxon | 12108 |
| [12109] Cocconeis pseudomarginata | Appellations de Taxon | 12109 |
| [1211] Scapaniaceae | Appellations de Taxon | 1211 |
| [12110] Cyclostephanos patagonicus | Appellations de Taxon | 12110 |
| [12111] Cyclotella pretemperei var. praetemperei | Appellations de Taxon | 12111 |
| [12112] Craspedoporus truanii | Appellations de Taxon | 12112 |
| [12113] Cavinula protractolapidosa | Appellations de Taxon | 12113 |
| [12114] Cymbopleura pertruncata | Appellations de Taxon | 12114 |
| [12115] Cyclotella plitvicensis | Appellations de Taxon | 12115 |
| [12116] Cymbopleura platycephala | Appellations de Taxon | 12116 |
| [12117] Cymbella pantocsekii | Appellations de Taxon | 12117 |
| [12119] Cocconeis placentula abnormal form | Appellations de Taxon | 12119 |
| [1212] Scapania | Appellations de Taxon | 1212 |
| [12120] Cymbopleura petrovskae | Appellations de Taxon | 12120 |
| [12121] Cymbopleura perstechlinensis | Appellations de Taxon | 12121 |
| [12122] Cocconeis peltoides | Appellations de Taxon | 12122 |
| [12123] Capartogramma pumila | Appellations de Taxon | 12123 |
| [12124] Cymbella pervarians | Appellations de Taxon | 12124 |
| [12126] Cymbella parvulissima | Appellations de Taxon | 12126 |
| [12127] Eunotia tenella var. densestriata | Appellations de Taxon | 12127 |
| [12128] Eunotia tecta | Appellations de Taxon | 12128 |
| [12129] Encyonema temperei | Appellations de Taxon | 12129 |
| [1213] Scapania undulata | Appellations de Taxon | 1213 |
| [12130] Eunotia testudinata | Appellations de Taxon | 12130 |
| [12131] Eunotia tetraodon | Appellations de Taxon | 12131 |
| [12132] Eunotia trigibba | Appellations de Taxon | 12132 |
| [12133] Encyonopsis tiroliana | Appellations de Taxon | 12133 |
| [12134] Eunotogramma laevis | Appellations de Taxon | 12134 |
| [12135] Eunotia tapacumopsis | Appellations de Taxon | 12135 |
| [12136] Eunotia tenelloides | Appellations de Taxon | 12136 |
| [12138] Encyonema tenerum | Appellations de Taxon | 12138 |
| [12139] Encyonema tenuissimum | Appellations de Taxon | 12139 |
| [1214] Trichocoleaceae | Appellations de Taxon | 1214 |
| [12140] Encyonema stigmoideum | Appellations de Taxon | 12140 |
| [12141] Encyonema subtenerum | Appellations de Taxon | 12141 |
| [12142] Encyonema subtriste | Appellations de Taxon | 12142 |
| [12143] Encyonema subturgidum | Appellations de Taxon | 12143 |
| [12144] Eunotia subarcuatoides | Appellations de Taxon | 12144 |
| [12145] Eunotia tapacumae | Appellations de Taxon | 12145 |
| [12146] Encyonema tropicum | Appellations de Taxon | 12146 |