Archilobesia formosana Diakonoff, 1973 is newly recorded from Japan. Larvae were collected from the leaves of Glochidion rubrum Blume (Phyllanthaceae) on Iriomote-jima Island, representing the first documented host plant record for the genus. We provide a redescription of the adult along with the first illustration of the male genitalia.

The larva and pupa of Hedya anaplecta (Meyrick) are described and illustrated for the first time. In Japan, larvae feed on Elaeocarpus japonicus and E. zollingeri var. zollingeri (Elaeocarpaceae).

The neotype of the subspecies Neptis iwasei setoensis Fukúda & Minotani, 2000 (Nymphalidae) is designated because of the loss of the holotype specimen. The neotype is deposited in the collection of National Museum of Nature and Science, Ibaragi, Japan.

This study was performed to objectively evaluate the changes in wing color of the painted lady butterfly (Vanessa cardui Linnaeus) by numerical expression of color using the three attributes of the Munsell color system (hue, value and chroma). The results suggested a relation between length of pupal stage and changes in wing color, with an increase in length of pupal stage associated increases in hue and decreases in value and chroma, with some regional differences in the wing. Marked decreases were seen in value and chroma of the underside of the hindwing, while minor changes were observed in hue in all regions of the wing, with no significant differences between males and females. Numerical evaluation of the wing color of field-captured butterflies using the Munsell color system indicated that the typical changes appearing in winter were decreases in value and chroma, with no marked changes in hue. The results showed that the Munsell color system was applicable for objective evaluation of changes in wing color of the painted lady butterfly, and it could allow rough estimation of the length of pupal stage of the butterfly.

A new species of the genus Nemophora, N. takaosana Hirowatari & Yagi sp. nov., was unexpectedly found at the foot of Mt. Takao (Takaosan), Tokyo, Japan. This species might have gone unnoticed until now due to its small size, compared to other members of the family Adelidae, and its unusual emergence from late September to early October among the Japanese Adelidae. We compared this new species with its close relatives, based on their morphological characteristics and DNA barcodes.

During faunistic surveys of insects associated with halophytes in the tidal flats of the Ariake Sea coast, we found that two species, Coleophora serinipennella (Lepidoptera: Coleophoridae) and Baris scolopacea (Coleoptera: Curculionidae) induce stem galls on Atriplex patens (Amaranthaceae). This is the new host plant records for the two species. Because galls induced by the two species are very similar in size, they were difficult to identify the inducer in appearance.

Chionodes kobayashii sp. nov. collected from Mt. Nokogiri-dake at Yamanashi Prefecture is described with a series of photos of adult and male genitalia.

The precise type locality of Depressaria spectrocentra Meyrick, 1935, which had been uncertain for many years, was identified as Chikuzen Okinoshima in Fukuoka Prefecture, Japan. In addition to the previously known host plant Chrysanthemum pacificum (Asteraceae), we found the larvae also feed on C. kinokuniense.

In the subgenus Fabriciana of the genus Argynnis, three distinct species of Japanese high brown fritillaries are recognized. It has been noted that identifying females of the three species can be particularly challenging. This study focuses on two of the three species, referred to by their Japanese names, Sato Uragin-hyoumon and Yamo Uragin-hyoumon, henceforth denoted as "sato" and "yama" for simplicity. Through discriminant analysis (DA) of morphological traits including wing shape, wing veins, and marking spots, significant differences between the two species were identified. This analysis enabled the discrimination of type series specimens. Specifically, A. addipe kurosawae Matsumura, 1915 from the Hokkaido University Museum was assigned to the species sato. Additionally, examination of seven type females of A. locuples Butler, 1881 from the Natural History Museum (NHM), London revealed a composition of five sato and two yama females. Consequently, A. nagiae Shinkawa et Iwasaki, 2019, previously tentatively assigned as the name-bearing type of yama, can now be confidently positioned within the taxonomy.