| [A] Aeropyrum pernix | AERPE01218 | Q9YAT2 | Hypothetical protein |
| [A] Ignicoccus hospitalis (strain KIN4/I / DSM 18386 / JCM 14125) | IGNH400259 | A8A941 | Phosphoesterase, putative |
| [A] Hyperthermus butylicus (strain DSM 5456 / JCM 9403) | HYPBU00262 | A2BJI2 | Phosphoesterase, ICC-like protein |
| [A] Metallosphaera sedula (strain ATCC 51363 / DSM 5348) | METS501712 | A4YHI7 | Phosphoesterase, putative |
| [A] Sulfolobus acidocaldarius | SULAC01235 | Q4J960 | conserved Archaeal protein |
| [A] Sulfolobus islandicus (strain L.S.2.15 / Lassen #1) | SULIL01202 | C3MPQ6 | |
| [A] Sulfolobus islandicus (strain M.14.25 / Kamchatka #1) | SULIM01128 | C3MYQ0 | |
| [A] Sulfolobus islandicus (strain M.16.27) | SULIA01172 | C3N5D2 | |
| [A] Sulfolobus islandicus (strain Y.G.57.14 / Yellowstone #1) | SULIY01211 | C3NDY6 | |
| [A] Sulfolobus islandicus (strain Y.N.15.51 / Yellowstone #2) | SULIN01460 | C3NHR7 | |
| [A] Sulfolobus solfataricus | SULSO00859 | C5SS44 | Putative uncharacterized protein |
| [A] Sulfolobus tokodaii | SULTO01368 | Q971V2 | hypothetical protein |
| [A] Thermofilum pendens (strain Hrk 5) | THEPD00917 | A1RYP7 | Phosphoesterase, putative |
| [A] Archaeoglobus fulgidus | ARCFU01133 | O29110 | Putative uncharacterized protein |
| [A] Methanobacterium thermoautotrophicum | METTH01759 | O27831 | Conserved protein |
| [A] Methanocaldococcus jannaschii | METJA00036 | Y037_METJA | Uncharacterized protein MJ0037 |
| [A] Methanococcus maripaludis | METMP01142 | Q6LY50 | Metallo-phosphoesterase:Serine/threonine-specific protein phosphatase |
| [A] Methanococcus maripaludis (strain C5 / ATCC BAA-1333) | METM500440 | A4FX29 | Metallophosphoesterase |
| [A] Methanococcus maripaludis (strain C6 / ATCC BAA-1332) | METM601512 | A9AAG6 | Metallophosphoesterase |
| [A] Methanococcus maripaludis (strain C7 / ATCC BAA-1331) | METM700389 | A6VG86 | Metallophosphoesterase |
| [A] Methanococcus vannielii (strain SB / ATCC 35089 / DSM 1224) | METVS00453 | A6UPE9 | Metallophosphoesterase |
| [A] Pyrococcus abyssi | PYRAB00838 | Q9V0F2 | Phosphoesterase, putative |
| [A] Pyrococcus furiosus | PYRFU01472 | Q8U0U8 | Putative uncharacterized protein PF1484 |
| [A] Pyrococcus horikoshii | PYRHO01358 | O59035 | Putative uncharacterized protein PH1310 |
| [A] Thermococcus kodakaraensis | PYRKO01380 | Q5JH04 | metallophosphoesterase, calcineurin superfamily |
| [A] Picrophilus torridus | PICTO01098 | Q6L019 | Putative ICC-like phosphoesterases |
| [A] Thermoplasma acidophilum | THEAC00529 | Q9HKQ9 | Phosphoesterase related protein |
| [A] Thermoplasma volcanium | THEVO00591 | Q97B67 | Putative uncharacterized protein TVG0579516 |
| [A] Korarchaeum cryptofilum (strain OPF8) | KORCO01072 | B1L5V3 | Predicted ICC-like phosphoesterase |
| [A] Nanoarchaeum equitans | NANEQ00351 | Q74N03 | NEQ358 |