We document the occurrence of Early Triassic (Olenekian) crinoid ossicles in exotic blocks contained within the black limestone unit of the Thaynes Formation, which overlies the Dinwoody Formation at the classic Crittenden Springs Smithian ammonoid locality. Crinoid ossicles include two species, i.e., Holocrinus sp. and Articulata ord., fam., gen. et sp. indet. Furthermore, two co-occurring, age diagnostic conodonts, i.e., Neospathodus pakistanensis and Ns. posterolongatus, constrain the age of the crinoids from the early Smithian to the earliest middle Smithian. This discovery represents the third report of Smithian Holocrinidae in the Panthalassan area and it provides important data for the study of crinoid recovery during the Early Triassic.

Ontogeny and variation of the three barroisiceratine ammonoids Yabeiceras orientale Tokunaga and Shimizu, Yabeiceras cf. manasoaense Collignon, and Forresteria (F.) yezoensis Matsumoto were studied by means of X-ray micro-computer tomography based on the well-preserved material from the probable upper Turonian Obisagawa Member of the Ashizawa Formation, Futaba Group in Fukushima Prefecture, northeast Japan. Specimens of Y. orientale, F. (F.) yezoensis, and F. (F.) muramotoi from the Coniacian of the Yezo Group in Mikasa City, central Hokkaido, northern Japan were also examined for comparison. As the shell of Y. orientale grows, the relative umbilical size (U/D) becomes rapidly larger at shell diameter (D) of 30–50 mm, and the relative whorl thickness (W/H) first increases to the stage of 30–50 mm in D and then decreases gradually. The growth rate of whorl width in costal section (W) is relatively constant up to a diameter of 30–50 mm and then decreases gradually, whereas that of whorl height (H) is relatively constant throughout ontogeny. The intraspecific variations in U/D and W/H in middle whorls are wider than those in early and late whorls, as evidenced by the data from the present and previous studies. As the shell of F. (F.) yezoensis grows, U/D is almost constant, and W/H decreases gradually after D exceeds 30–50 mm. Forresteria (F.) yezoensis shows relatively narrow intraspecific variations in relative umbilical size and whorl thickness, as evidenced by the measurement data from the present and previous studies.

The Iwaki insect-bearing amber from Fukushima Prefecture, northeastern Honshu, Japan, is considered from the Late Cretaceous Coniacian age. The insect-bearing amber localities from that period are few worldwide. Here, we report Iwakia longilabiata gen. et sp. nov., a new fossil genus and species of the infraorder Cimicomorpha Leston, Pendergrast and Southwood, 1954 (Hemiptera: Heteroptera) from the Futaba Group of Iwaki City. Although the preservation is incomplete, this fossil is provisionally placed in the family Microphysidae Dohrn, 1859 based on the general consistency of the diagnostic characters of the family. The fossil is distinguishable from any genus of Cimicomorpha including Microphysidae because of its long labium and brachypterous female. Additionally, the fossil shares the female diagnostic characteristics of the Palaearctic and Nearctic taxa, suggesting that it is an early stage in the evolution of sexual dimorphism of the family Microphysidae. The evolution of sexual dimorphism in Microphysidae may have already occurred in East Asia during the Late Cretaceous Coniacian age. This fossil may be the first discovery from Asia and the oldest record of the family Microphysidae.

Five species of Late Cretaceous ammonoids, Yezoceras miotuberculatum, Yezoceras elegans, Eubostrychoceras indopacificum, Pseudoxybeloceras sp., and Yabeiceras orientale, have been identified from the Obisagawa Member of the Ashizawa Formation, Futaba Group, Fukushima Prefecture, northeastern Japan. Notably, Yezoc. miotuberculatum, Yezoc. elegans, and the genus Pseudoxybeloceras, previously known from the Yezo Group in Hokkaido, northern Japan, were identified for the first time from the Futaba Group. The presence of Yezoc. miotuberculatum and Yezoc. elegans indicates faunal similarities between the Ashizawa Formation and the Yezo Group in Hokkaido. Co-occurrence of age-diagnostic inoceramids suggesting latest Turonian to earliest Coniacian age allows us to provide a detailed biostratigraphic correlation between the Futaba and Yezo groups.

This study describes a new fossil butterfly species, Tacola kamitanii sp. nov., from the Upper Pliocene to the Lower Pleistocene Teragi Group in Hyogo Prefecture, Japan. The new fossil is characterized by remarkably large wings, with an estimated forewing length of 48 mm and a wingspan of 84 mm. This new fossil species belongs to the genus Tacola based on the following characteristics: both discal cells open, smoothly curved humeral veins, and a thick thorax and abdomen. However, it does not identify with any modern relatives of Tacola with a small discal cell, straight 1A + 2A anal vein of the forewing, or long hindwing median vein. Therefore, the fossil was identified as a new species of the genus Tacola and one of the largest species in the subfamily Limenitidinae. The modern relatives of Tacola are distributed in the subtropics and tropics, while this fossil species may have survived in the temperate zone. This is the first named Limenitidini fossil and the youngest example of an extinct butterfly.