The distribution of Parmotrema tinctorum, known as an excellent bioindicator of air pollution, was examined in Kanagawa Prefecture, Japan, by comparing data from 2005–2007 with that from 2022. Field investigations were conducted in cemeteries and parks at 140 sites in 2005–2007 and at 128 sites in 2022. In 2005–2007, a large gap in the distribution of this species was observed in urban areas with higher concentrations of NO, NO₂ and SPM likely due to automobile exhaust emissions. In 2022, the recolonization of P. tinctorum was observed at six sites, and one new growth site was confirmed within the gap area of 2005–2007. The recolonization in the urban area is considered to be related to the significant improvement in air quality, due to the strict regulation of exhaust gas from diesel engines implemented since 2003 in and around Tokyo, including Kanagawa Prefecture. Similar phenomena of recolonization of P. tinctorum have also been reported within Tokyo, supporting this conclusion.

Sarmentypnum exannulatum (Schimp.) Hedenäs is reported as new to Myanmar. The description and illustration based on Myanmar plants are given. This species is characterized by the leaves serrulate and smooth when dry, costa ending nearly 3/5 leaf length and alar cells inflated in auriculate groups. The ecological note on the habitat is given.

Astomiopsis julacea (Besch.) K.L.Yip & Snider is rediscovered from Japan after its description in 1898. Based on the phylogenetic analysis with newly acquired DNA data, the species is resolved in the clade of Ditrichopsis, not in the Astomiopsis. Reassessment of morphological characters also suggests that A. julacea rather shares the characteristics with Ditrichopsis than Astomiopsis, and a new combination of Ditrichopsis julacea (Besch.) Y.Inoue is proposed. The recognition of D. julacea extends the distribution of Ditrichopsis to the east. Astomiopsis should be considered as an American genus.

A critically endangered aquatic species, Potamogeton lucens (Potamogetonaceae), was discovered in a newly constructed flood-control reservoir adjacent to the Gogyo River in Tochigi Prefecture, Japan. Morphological observation and DNA sequencing were performed to identify the species. The plant likely re-emerged from seeds buried in the soil. The site at which the reservoir was constructed had previously been a paddy field since at least 1961, and it has been hypothesized that P. lucens seeds can remain dormant in the soil for several decades. In addition, many other aquatic species have appeared, including Potamogeton wrightii, Stuckenia pectinata (Potamogetonaceae), Najas chinensis and Ottelia alismoides (Hydrocharitaceae). These results indicate the potential of flood-control reservoirs as habitats for aquatic plants, emphasizing their importance in the regeneration and conservation of aquatic plant diversity.

The nomenclature of Musa basjoo (Musaceae) is discussed. Musa basjoo Siebold ex Miq. is the earliest valid name for the species, and a lectotype is here designated. Due to the ambiguity of the original material, an epitype is also designated here to stabilize the application of the name.

Molecular phylogenetic analysis was conducted using single-nucleotide polymorphism data from Chinese plants with pubescent stems, similar to Cassytha filiformis var. duripraticola, which has been known to distribute in Japan and Taiwan. The phylogenetic analysis demonstrated that the Chinese plants were included in the same clade with plants of C. filiformis var. duripraticola obtained from Japan and Taiwan. This study is the first report of C. filiformis var. duripraticola from Mainland China based on the morphological and molecular features.