1.

論文(リポジトリ)

論文(リポジトリ)
Fuke, Yusuke ; Imai, Hideyuki ; 福家, 悠介 ; 今井, 秀行
出版情報: Fauna Ryukyuana.  44  pp.7-15,  2018-07-31.  Ryukyu University Museum, Fujukan — 琉球大学資料館 (風樹館)
URL: http://hdl.handle.net/20.500.12000/42406
概要: This paper reports the finding of one of the Palaemonidae freshwater prawns, Macrobrachium ustulatum, on Okinawa-jima Is land, Ryukyu Archipelago, Japan. This represents the first record of this species in this country and also the northernmost distributional record of the species. Macrobrachium ustulatum redescribed by Castelin et al. (2017) is a cryptic species of M. australe. However, there was uncertainty in the assignation of two nomina to Castelin’s et al. (2017) molecularly identified two species. Moreover, among females, it is difficult to recognize clear morphological differences between M. ustulatum and M. australe. Therefore, we examine their validity of the taxonomic identification based on DNA sequences using the mitochondrial 16S rRNA gene and the nuclear 28S rDNA gene as well as morphological analyses. Consequently, these results supported the identification of the previous study.<br />琉球列島沖縄島北部の河川から得られたテナガエビ科のMacrobrachium ustulatumの標本を記録した. これは本種の日本初記録であると同時に, 分布の北限記録となる. 本種は長らくザラテテナガエビM. australeの新参異名とされてきたが, Castelin et al. (2017) により独立種として再記載された. しかし, 分子系統解析によって認識された2種への名義の割り当ての妥当性には不明確な部分があった. そこで本報告では, 両種について形態形質とミトコンドリアDNAの16S rRNAと核DNAの28S rDNA領域を用いた相同性検索を併用することで, 先行研究で行われた分類の妥当性を検証した. その結果, 先行研究の結果を支持する証拠が得られ, それに従って両種の同定を行った. 併せて, Macrobrachium ustulatumの標準和名としてナンヨウテナガエビを提唱し, その基準標本にRUMF-ZC-4626を指定した. Macrobrachium australeの標準和名は従来通りザラテテナガエビとし, 和名の基準標本にRUMF-ZC-4645を指定した. 続きを見る
2.

論文(リポジトリ)

論文(リポジトリ)
丸山, 智朗 ; 福家, 悠介 ; Maruyama, Tomoaki ; Fuke, Yusuke
出版情報: Fauna Ryukyuana.  43  pp.11-17,  2018-06-19.  Ryukyu University Museum, Fujukan — 琉球大学資料館 (風樹館)
URL: http://hdl.handle.net/20.500.12000/42386
概要: An atyid shrimp, Caridina macrodentata Cai & Shokita, 2006 is newly recorded based on two female specimens collected from Okinawa-jima Island, Ryukyu Archipelago, southwestern Japan. This record extends the distributional area of the species to the north. The specimens were caught in March 2017 from two rivers into which a large amount of spring water flows. They seemed to have overwintered due to the presence of relatively warm spring water. As a result of examining 21 specimens from the Ryukyu Archipelago, the range of the rostral teeth formula was 0–4+10–14 (11–17)/1–6, and the maximum size was 7.5 mm CL, 25.9 mm BL. It turned out that living adult individuals have no color pattern on their sides, but their dorsal midline is whitish, and the color of the distal portions of the telson and uropods are creamy and clearly differentiated from the rest of brown telson and uropods. 続きを見る