Redescription of the Sea Anemone Exocoelactis actinostoloides (Cnidaria: Anthozoa: Actiniaria) Based on a Topotypic Specimen Collected from Tokyo Bay, Japan

Abstract

We collected a specimen of Exocoelactis actinostoloides (Wassilieff, 1908) from the type locality of the species in October, 2012. The name of Ex. actinostoloides has been misapplied to a species of Entacmaea (Ehrenberg, 1834) around the Indo-Pacific region in many works, including scientific reports, although some authors have noted the error. A true specimen of Ex. actinostoloides has not been found in Japanese waters since the collection of the type specimen at Jogashima, Kanagawa Prefecture, in 1904. Here, we redescribe Ex. actinostoloides based on the present specimen from the opposite side of the Uraga Strait, and analyze the phylogenetic position of this species within Actiniaria based on mitochondrial 12S and 16S rDNA sequence data. These are the first molecular data ever provided for the family Exocoelactinidae. The sequence data indicate that Ex. actinostoloides is a member of the superfamily Actinostoloidea, and that it is most closely related to the family Actinostolidae.

Description of three new species of Scolanthus (Cnidaria, Anthozoa, Actiniaria, Edwardsiidae): first records of the genus from Japan

“…Images of the cnidae were obtained by differential interference contrast microscopy (Yanagi et al 2015). The length and width were measured using the software ImageJ v. 1.49 (Rasband 1997–2012).…”

Re-description of <i>Metedwardsia akkeshi</i> (Cnidaria: Anthozoa: Actiniaria: Edwardsiidae), Discovered in Akkeshi, Hokkaido, Almost 80 Years after Original Description, with a Revision of the Diagnosis of Genus <i>Metedwardsia</i>

“…Cnidae were observed for the tentacle, column, actinopharynx, and filament, and collected from specimens as follows: NSMT-Co 1605, CMNH-ZG4314. Cnidae images were all taken via differential interference contrast microscopy (Yanagi et al 2015) at NSMT, and length and width were measured by ImageJ v.1.49 software (Rasband 1997(Rasband -2012. Cnidae nomenclature follows that of Mariscal (1974).…”

Redescription of Synactinernus flavus for the First Time after a Century and Description of Synactinernus churaumi sp. nov. (Cnidaria: Anthozoa: Actiniaria)

“…Tissue from each organ was placed on slide glasses and mounted using 50% (v/v) glycerin seawater solution. Images of the cnidae were obtained by differential interference contrast microscopy (Yanagi et al, 2015). The length and width were measured using the software ImageJ ver.…”