A single specimen collected from the Campanian Wenonah Formation in New Jersey forms the basis for definition of a new genus and species of dromiid crab, Costadromia hajzeri. This occurrence represents the oldest known occurrence of Dromiidae. The discovery represents only the second decapod crustacean found in the formation and brings the total number of Cretaceous decapods in New Jersey to 23.

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Fourteen specimens of pagurized gastropods are completely enveloped by anascan cheilostome bryozoan colonies, and most of them bear serpulid worm tubes referred to Hydroides sp. These specimens from the Oligocene River Bend Formation in North Carolina constitute the first such occurrence on the Atlantic coastal region of North America.

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Specimens collected from the Lower Cretaceous (Albian) Hudspeth Formation, Oregon, are referable to Anoplocarcinus hudspethi new genus, new species. The new taxon is supported by phylogenetic analysis as well as comparison to type and referred material within Orithopsidae of Raninoida. Albian decapods are rare from the Pacific Coast of North America; this is only the third decapod species reported from the region. Orithopsidae is already well-known from Early Cretaceous occurrences worldwide, and although the new taxon does not extend the geologic range for the family, it expands the biogeographic distribution and morphological diversity among Early Cretaceous orithopsids.

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A new species of crab, Caloxanthus kavanaghi, found at the base of the Del Rio Formation in central Texas, USA, has characters referring to Caloxanthus.

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Two new species of Longodromitidae, Planoprosopon ogawaense and Planoprosopon sarumaru, are described, based upon examination of the previously known and new specimens of crabs from the Torinosu Group (Upper Jurassic–Lower Cretaceous), Shikoku, Japan. Both species together with goniodromitids from the Torinosu Group (Karasawa and Kato, 2007) and a longodromitid from the Somanakamura Group (Kato et al., 2010) represent the oldest records of Brachyura known from the circum-Pacific realm.

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Re-examination of the type and additional specimens of Callianassa (s.l.) sakakuraorum Karasawa, 2000, from the Arida Formation (Barremian, Lower Cretaceous) of Japan, shows that Callianassa (s.l.) sakakuraorum is moved to Micheleidae Sakai, 1992, from Callianassidae Dana, 1852. Amatukamius, a new monotypic genus is proposed for Callianassa (s.l.) sakakuraorum. A re-description is given for the species. The occurrence of Amatukamius from the Barremian of Japan represents the oldest record for Micheleidae.

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Seven species of decapods are described from the Izumi Group (Upper Cretaceous: Campanian–Maastrichtian) of Hyogo and Osaka Prefectures, central Japan. Archaeopidae, a new family of Retroplumoidea embraces the monotypic Late Cretaceous genus Archaeopus. Hinecaris simplex, a new genus and species is the first record for the axiidean family Axiidae from the Cretaceous rocks of Japan. “Callianassa” (s.l.) masanorii Karasawa, 1998, is re-described and is moved from Callianassidae to Gourretiidae. A re-description is given for Linuparus japonicus Nagao, 1931, and Archaeopus ezoensis (Nagao, 1941). The lectotype for Linuparus japonicus Nagao, 1931, is herein designated.

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Four new species of the freshwater snail in the genus Semisulcospira are described from the early Pleistocene Gamo Formation and the late Pliocene Ayama and Koka Formations of the Kobiwako Group in central Japan. These four new species belong to the subgenus Biwamelania. Semisulcospira (Biwamelania) reticulataformis, sp. nov., Semisulcospira (Biwamelania) nojirina, sp. nov., Semisulcospira (Biwamelania) gamoensis, sp. nov., and Semisulcospira (Biwamelania) tagaensis, sp. nov. are newly described herein. The authorship of Biwamelania is attributed to Matsuoka and Nakamura (1981) and Melania niponica Smith, 1876, is designated as the type species of Biwamelania by Matsuoka and Nakamura (1981).

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A fossil pearl attached on the inner surface of a right valve of Crenomytilus grayanus (Mollusca: Bivalvia: Mytilidae) is recorded from the lower Miocene Akeyo Formation of the Mizunami Group of Gifu Prefecture, central Japan. This represents the third record for the pearl from the Mizunami Group.

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The Mizunami Fossil Museum modified its exhibition on July of 2018. The plan for the new exhibition is based on the following ideas: 1. The old corner “Chino-megumi” consisted of earthenware pottery, “Mino-yaki” pottery and minerals changed into Mysticete fossils Isanacetus sp. cf. I. laticephalus (MFM18127) and Crenomytilus grayanus (MFM16000). 2. The illustrations of the skeleton of the genus Isanacetus, and a paleoecological reconstruction of Isanacetus and C. grayanus were exhibited. 3. The skeleton of the genus Isanacetus was reconstructed based on the Isanacetus laticephalus (MFM28501 and MFM18004) and Isanacetus sp. cf. I. laticephalus (MFM18127). Missing parts (e.g., radius and ulna) were modeled on extant species of Eschirichtius robustus. 4. A paleoecological reconstruction of Isanacetus and C. grayanus was presented as an illustration. The form of Isanacetus was reconstructed based on the reconstructing skeleton. 5. T. Kimura supervised the illustration of the reconstructed Isanacetus and Y. Ando supervised the illustration of the reconstructed C. grayanus. 6. Video recordings including the process of generating the paleoecological reconstruction of Isanacetus and researching fossils at the construction site are broadcast by digital signage in the new exhibition.

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