Cerianthus japonicus Carlgren, 1924

Stampar, Sergio N., Reimer, James D., Maronna, Maximiliano M., Lopes, Celine S. S., Ceriello, Hellen, Santos, Thais B., Acuna, Fabian H. & Morandini, Andre C., 2020, Ceriantharia (Cnidaria) of the World: an annotated catalogue and key to species, ZooKeys 952, pp. 1-63 : 1

12 Cerianthus japonicus Carlgren, 1924

Cerianthus japonicus Carlgren, 1924: 173-175, Uchida 1979: 185-194; Molodtsova 2000: 19; Molodtsova 2001b: 913

Type locality.

Aburatsubo, Misaki (Sagami Bay), Japan.

Distribution.

Sagami Bay and Miyazaki, Kyushu Island, Japan; North Hamgyong Province, North Korea, at 10-100 m depth.

Remarks.

The original species description was based on two small specimens, one from North Korea (North Hamgyong Province) and the other one from Japan, Aburatsubo, Misaki (Sagami Bay). The description is quite adequate and presents the most important characteristics of the species. However, as noted by Molodtsova (2001b), differences between C. japonicus and C. punctatus Uchida, 1979 are very subtle. There are only two reliable characters that can be used to differentiate the two species: (1) the organization of the tentacular pseudocycles and (2) the number of mesenteries attached to the siphonoglyph. The first is a plastic character and intraspecific variation has been reported ( Carlgren 1912a; Arai 1965), while the second seems to be consistent ( Stampar et al. 2016). However, figure 4 by Carlgren (1924) does not allow verification if the third pair of mesenteries (P3) is in contact with the siphonoglyph or not. If the siphonoglyph format is the same as indicated by Uchida (1979), the P3 is probably also connected. Most data indicate that C. punctatus is synonymous to C. japonicus , which currently cannot be confirmed based on the available data.

Type material.

Museum of Evolution- Evolutionsmuseet (Uppsala University - ZTY 2516) (Holotype).