The history of studies on the taxonomy of Japanese hypocrealean entomopathogenic fungi is reviewed in each of the following seven periods: (1) research until the introduction of formal research of hypocrealean entomopathogenic fungi by M. Miyoshi (before 1888); (2) progress of Japanese hypocrealean entomopathogenic fungi research after A. Yasuda’s studies on Isaria (1894–1939); (3) research by Y. Kobayashi and D. Shimizu after Kobayashi’s monograph of Cordyceps s.l. and researches during that period (1941–1997); (4) the beginning of taxonomic research based on molecular phylogenetic analysis (2000–2011); (5) taxonomic revision based on “One Fungus = One Name” (2011–2017); (6) further progress in recent taxonomic research (2014–present); and (7) construction of online databases for scientific names (2000–present). We discussed the current status and issues concerning the taxonomy of these fungi in Japan and pointed out the following: there are many new taxa that are thought to be new to Japan which have been included in illustrated books and lists without their scientific names; basic information such as the exact number of species is insufficient; and it is likely that there are still many species whose genus needs to be reexamined and new combinations are needed. Comprehensive taxonomic research covering a wide range of Japanese hypocrealean entomopathogenic fungi is needed.

Two new species, Impatiens arakanensis Nob.Tanaka & T.Sugaw. (Balsaminaceae) and I. cirrosa Nob.Tanaka & T.Sugaw., from the Arakan Mountain Range, Magway Region, southwestern Myanmar, are described here. Impatiens arakanensis is similar to I. decipiens Hook.f. in floral morphology and coloration, but differs in having axillary inflorescence (vs. terminal), smooth dorsal petals (vs. with horn-like appendage), and pubescent lower sepal (vs. glabrous). Impatiens cirrosa is similar to I. tripetala Roxb. in floral morphology, but differs in having purple lower sepals (vs. orange to pale orange) with filamentous cirrus at apex, connate lateral united petals (vs. free) and white ovary with red spots (vs. green). Both of the two new species likely belong to Impatiens subgenus Impatiens sect. Uniflorae.

Phylogenetic analyses of all diploid taxa of Sceptridium in Japan were conducted using genome-wide SNPs obtained through Multiplexed ISSR Genotyping by sequencing. Our analyses revealed that samples identified as S. nipponicum formed two distinct genetic clusters. One cluster (Cluster 1) was found to be sister to S. triangularifolium, while the other (Cluster 2) was sister to S. microphyllum. Morphological observations of the two clusters confirmed that Cluster 2 can be distinguished from Cluster 1 by its blunt serrations and rounded pinnule apices. Since the lectotype specimen of S. nipponicum exhibits the morphological characteristics of Cluster 1, we describe Cluster 2 as a new species, Sceptridium laterifolium So.Ishii & Sahashi.

The nomenclatural status of nine names in the genus Gentiana (Gentianaceae), G. albicalyx, G. cachemirica, G. decemfida, G. hugelii, G. karelinii, G. kurroo, G. leucomelaena, G. prostrata and G. stipitata has been reviewed in accordance with ICN. After careful review of the protologues, original materials, and pertinent literature, lectotypification has been done for five of these names.

The name Cirsium phulchokiense Kitam. is here lectotypified amongst the syntypes based on ICN (Madrid code).

A new combination for the white flowered form of Aegonychon zollingeri (A.DC.) Holub, f. albidum (Honda) H.Ohashi, is proposed.