A new species of the genus Travisia Johnson, 1840, the single genus of the family Travisiidae, is described. Specimens of Travisia sanrikuensis sp. nov. were collected in the Sanriku region, Japan, from the lower bathyal zone (871–1684 m depth) of the northwestern Pacific. Molecular phylogenetic analysis based on partial 16S rRNA gene sequences revealed that the new species is phylogenetically close to Travisia brevis Moore, 1923, but differs from all congeneric species by the following morphological characters: 25 segments, 20 chaetigers, and 19–20 pairs of cirriform branchiae starting from chaetiger 2.
Specimens of two species of lernaeopodid copepods, Salmincola edwardsii (Olsson, 1869) and Salmincola markewitschi Shedko and Shedko, 2002, were collected from chars (Salvelinus spp.) reared in exhibition tanks of the Sapporo Salmon Museum, Hokkaido, Japan. Descriptions of these copepods are provided using the specimens. In 1988, adult females of S. edwardsii were found on the gills of southern Asian Dolly Varden, Salvelinus malma krascheninnikova Taranetz, 1933, and those of S. markewitschi in the buccal cavity of whitespotted char, Salvelinus leucomaenis (Pallas, 1814), Nikko char, Salvelinus leucomaenis pluvius (Hilgendorf, 1876), and brook trout, Salvelinus fontinalis (Mitchill, 1814). These copepods are considered to have been introduced to the museum in the late 1980s along with wild chars transported live from natural waters of Hokkaido. Adult copepods have been manually removed using forceps once or twice a year from reared chars, but such infrequent practices have not been effective to eliminate S. markewitschi, which was thus collected again in 2020. In contrast, S. edwardsii was completely eliminated by stopping rearing an infected population of southern Asian Dolly Varden, to which this parasite is host-specific.
A new species from the cockroach genus Eucorydia Hebard, 1929 from Miyako-jima Island of the Nansei Islands in Southwest Japan was compared to six closely related congeners; E. yasumatsui Asahina, 1971; E. donanensis Yanagisawa, Sakamaki, and Shimano, 2020; E. tokaraensis Yanagisawa, Sakamaki, and Shimano, 2020; E. dasytoides (Walker, 1868); E. guilinensis Qiu, Che, and Wang, 2017; and E. pilosa Qiu, Che, and Wang, 2017. The new species Eucorydia miyakoensis Yanagisawa, Sakamaki, and Shimano, sp. nov. from Miyako-jima Island was characterized by a small overall male body length of 12.5–13.0 mm and tegmina with an uninterrupted orange transversal band in the middle, and a pair of orange pubescent patches at the base. Eucorydia yasumatsui, E. donanensis, E. tokaraensis, the zonata population of E. dasytoides, and E. miyakoensis were divided into five lineages in a maximum likelihood tree generated from a dataset concatenated from five molecular markers (two nuclear: 28SrRNA and histone H3, and three mitochondrial: COII, 12SrRNA, and 16SrRNA). We recognized E. miyakoensis as a distinct species, which was also supported by the pairwise genetic distances (3.4%–6.7%, K2P) of the COI sequences to the other Japanese Eucorydia species.
The sea anemone Capnea japonica (Carlgren, 1940) was described based on two specimens collected in 1914 off the coast of Misaki, Sagami Bay, Japan. Besides the two syntypes, no further specimens are known to have been collected. The original description of C. japonica is brief, and, therefore it is difficult to identify the species based on the available information. In 2014, we collected a single specimen of Capnea Gosse, 1860 from around the type locality of C. japonica and examined its morphological characters, such as the external features, cnidome, and musculature, and then compared it with the syntypes of C. japonica. The characteristic form of tentacles, size and distribution of cnidae, and very strong sphincter muscle in our specimen were a good match to the original description and to the results of examining the syntypes. Based on the topotype and syntypes, we redescribe C. japonica and show its phylogenetic position with newly obtained DNA sequencing data.
Yunohamella varietas sp. n., from Ulsan Metropolitan City, Korea is newly described based on the male. The new species is closely related to Yunohamella lyrica (Walckenaer, 1841) and Yunohamella serpatusa (Guan and Zhu in Zhu et al., 1993), but can be distinguished from Y. lyrica and Y. serpatusa by the dorsal pattern of the abdomen, shape of embolus, conductor and median apophysis. The new species was collected with a sweep net in rice fields.