著者
Jun Kitaura Ryuta Yoshida Noboru Nunomura
出版者
Carcinological Society of Japan
雑誌
Crustacean Research (ISSN:02873478)
巻号頁・発行日
vol.47, pp.111-123, 2018-12-05 (Released:2018-12-05)
参考文献数
30

DNA sequences from a portion of the mitochondrial 16S rRNA gene were used to examine genetic differentiation among the local coastal populations of the Japanese wood-boring isopod Sphaeroma wadai Nunomura, 1994. Of the 15 haplotypes identified, only 3 were shared among the sampled localities. The most dominant haplotype was shared by all populations from the Japanese mainland. All haplotypes identified from Okinawa Island and Iriomote Island were endemic to each island. For the Japanese mainland group, the haplotype network showed a star-like shape, with rare haplotypes radiating from the central most common haplotype by only one or two mutation steps. Haplotypes identified from Iriomote Island were separated by many steps from those identified from all other sampled localities, and haplotypes identified from Okinawa Island were separated by several steps from those identified from the Japanese mainland. Phylogenetic analyses revealed the existence of two lineages: one comprising specimens from Iriomote Island and the other comprising specimens from the Japanese mainland and Okinawa Island. These two lineages diverged at an uncorrected p-distance of 9.1%–10.3%, probably representing a different species. There were no clear morphological differences between the two lineages except for the propodus length of the seventh pereopod of male individuals.
著者
Hiroyuki Ariyama Nobuhiro Saito Michitaka Shimomura
出版者
Carcinological Society of Japan
雑誌
Crustacean Research (ISSN:02873478)
巻号頁・発行日
vol.45, pp.29-35, 2016 (Released:2016-07-08)
参考文献数
13
被引用文献数
1 2

A new species of the euphausiid-ectoparasitic isopod in the genus Heterophryxus Sars, 1885 is described based on an immature female specimen collected from the central North Pacific. The new species, Heterophryxus pacificus, can be distinguished from the immature females of H. appendiculatus Sars, 1885 and H. elongatus Schultz, 1977 in having (1) a wider and thicker body, (2) a cephalon without an anterior hollow, and (3) complex-shaped pereomeres 2 to 4. A diagnosis of the genus Heterophryxus is provided.
著者
Christopher W. Ashelby Sammy De Grave Nguyên Van Xuân
出版者
Carcinological Society of Japan
雑誌
Crustacean Research (ISSN:02873478)
巻号頁・発行日
vol.47, pp.17-27, 2018-02-14 (Released:2018-02-14)
参考文献数
12
被引用文献数
3

A new species of Palaemon is described from Cần Giớ District, Vietnam. This species has previously been reported from Vietnam as a colour morph of Palaemon sewelli (Kemp, 1925), to which it is clearly morphologically very closely related. However, the new species can be separated from P. sewelli through the position of the branchiostegal tooth relative to the branchiostegal groove, the shape of the suborbital lobe, a hirsute carapace and abdomen and the colour pattern of living individuals. The description of this new species brings the number of species of Palaemon known from Vietnam to eleven species.