The penaeid ectoparasitic isopod, Minicopenaeon intermedium intermedium Bourdon, 1981, is recorded for the first time from Japan. This study provides additional information on this subspecies, including a new host, description, infection rate, keys, and morphological variation.
Fourty-one species of patala group and franciae group are discussed and figured. Seven new taxa, i.e., hisui sp. nov., intusfascia sp. nov., lao sp. nov., orientalis sp. nov., pauxilla sp. nov., takeru sp. nov. and wakoi sp. nov. are described.
The osteological description and illustrations of the cyprinid fish Candidia barbatus (Regan, 1908) from Kaohsiung County, Taiwan are provided for studies on fossil cyprinid fishes found in East Asia and Japan. As a result of this study, it was found that the dentary, opercle, urohyal and coracoid of C. barbatus are similar to those of the genus Nipponocypris. However, the parietal and infraorbital 5 of C. barbatus differ from those of the genus Nipponocypris. It is considered that these two morphological characteristics are typical of the genus Candidia.
Maxillary dentition of basal neoceratopsians was examined to understand the tooth replacement pattern in the early stage of neoceratopsian evolution. The replacement tooth developed on the lingual side of the functional tooth. For the replacement tooth to grow apically, resorption of the root and eventually the base of crown of the functional tooth was necessary. Having only one replacement tooth for each tooth position and involving resorption of the functional tooth for it to erupt, tooth replacement of basal neoceratopsians was inefficient compared to ceratopsids, the derived neoceratopsians.
The Ashiya Group (Late Oligocene) is distributed in the northern part of the Kyushu Island, West Japan, yields many cetacean fossils. Among them, an archaic mysticete is reported here. The fossil occurred at the Wakamatsu Coast of Kitakyushu City (Tominohana (cape), 33°56′09″N, 130°41′08″E), from siltstone of the Jinnobaru Formation, Ashiya Group. The material is composed of an almost complete skull with both dentaries, cervical vertebrae, anterior thoracic vertebrae, several ribs, and fore limb elements. Deformation of bones is limited. The specimen is described as Yamatocetus canaliculatus, new genus and new species in the Eomysticetidae SANDERS and BARNES, 2002. Yamatocetus canaliculatus has following characters: the rostrum is wide and long, indicating the presence of functional baleen: there are several alveoli along the grooves of lateral margin of upper jaws and dorsal margin of dentaries. The external naris opens anteriorly as seen in Eomysticetus whitmorei SANDERS and BARNES 2002, but different from E. whitmorei at the uplift of nasals and other features. Yamatocetus canaliculatus has advanced features in the anterior limb for swimming, the lengths of bones are different from extant species of mysticetes. The ribs are mostly two-headed, indicating a less flexible nature of the rib cage. It indicates that the whale was not adapted enough for deep diving, compared to extant baleen whales which have a limited number of two-headed ribs. The occurrence of Yamatocetus canaliculatus is important for discussion of early stage of the mysticetes, especially at the stage of loss of teeth. There are several species of such evolutionary stage in west coast of North Atlantic Ocean and New Zealand. They have migrated rapidly in the Late Oligocene.