| Name | Hypnum sordidum Müller Halle |
| Authorship | Müller Halle |
| Rank | Species |
| Placed in | Hypnum Hedwig |
| Citation | 1856 Bot. Zeitung (Berlin) 14(26): 457–458 |
| Holdings | 1 Specimen held in the Harvard University Herbaria identified as Hypnum sordidum Müller Halle |
| Identification made in | [no date] (1) |