Edwardsianthus pudicus (Klunzinger, 1877)

Izumi, Takato & Fujii, Takuma, 2021, Gems of the southern Japanese seas - four new species of Edwardsianthus (Anthozoa, Actiniaria, Edwardsiidae) with redescriptions of two species, ZooKeys 1076, pp. 151-182 : 151

publication ID	https://dx.doi.org/10.3897/zookeys.1076.69025
publication LSID	lsid:zoobank.org:pub:7B4E1271-0B60-4504-80B3-68028E4B1AD6
persistent identifier	https://treatment.plazi.org/id/11CE36E7-2E17-5D6A-A1F9-58A3E40FC11F
treatment provided by	ZooKeys by Pensoft
scientific name	Edwardsianthus pudicus (Klunzinger, 1877)
status

Treatment

New Japanese name: nanyo-mushimodoki-ginchaku Figs 2 View Figure 2 , 3A-E View Figure 3

Edwardsia pudica Klunzinger, 1877: 80-81, pl. 6, fig. 3; Carlgren, 1931: 18-20, figs 16, 17.

Edwardsiella pudica Andres, 1883: 309.

Edwardsia adenensis Faurot, 1895: 121, pl. 6, fig. 5, pl. 7, fig. 6.

Edwardsia bocki Carlgren, 1931: 7-9, figs 5, 6.

Edwardsia stephensoni Carlgren, 1950: 128-129, figs 1, 2.

Edwardsianthus pudica : England, 1987: 224-229, fig. 10.

Material examined.

NSMT-Co 1702: histological sections, dissected tissues, and prepared nematocysts, collected by SCUBA diving on 7 November 2015 off Kurasaki seashore, Amami-Oshima Island, Kagoshima, Japan, at ca. 20 m depth, by Takuma Fujii .

Description.

External anatomy. Size: ca. 120-200 mm in whole length, and ca. 12-15 mm in width in living specimen, and ca. 80-130 mm in length and ca. 8-10 mm in width in preserved specimen (Fig. 2A View Figure 2 ). Column: cylinder-like form, and the proximal part narrower to some extent; consisting of capitulum, scapus, and physa. The distal-most part capitulum, translucent and visible magenta mesenteries within, short, without nemathybomes. Scapus with very thick and easily removed periderm-like cuticle, dark gray color in living and preserved animals, and with tiny, pale white in color, densely scattered nemathybomes (Fig. 2A View Figure 2 ). Tentacles: 20 in number in two cycles, inner tentacle 8 and outer 12, magenta pink or purple in color with brown obscure patches in living animals (Fig. 2B View Figure 2 ; these colors are lost in preserved specimen), without acrospheres. Inner tentacles short, slender, ca. 5-6 mm in length, and outer ones long and slender, 10-14 mm in length in preserved. Mouth: at the center of oral disc, apparently swollen, showing white color in live specimens. Internal anatomy. Mesenterial arrangement: eight perfect mesenteries, all macrocnemes. Four dorsal and ventral directives, and four lateral mesenteries not paired with other macrocnemes. All macrocnemes present along whole length of the body from oral to aboral end and bearing distinct retractor and parietal muscles. Twelve tiny microcnemes, without muscles, confined only in distal-most part. Four microcnemes between dorsal directives and dorso-lateral mesenteries, four between dorso-and ventro-lateral mesenteries, and four between ventro-lateral mesenteries and ventral directives. Retractor muscles: at the mid part of column, strongly developed and diffused (Fig. 2F View Figure 2 ), pennon-like, arranged with ca. 100 muscular processes. Processes except some basal ones simple or slightly branched, and pinnate in some parts. Some processes nearest to body wall extremely well-branched, with secondary and tertiary branches (Fig. 2F View Figure 2 ; England, 1981: fig. 10). Parietal muscles: developed, comparatively distinct, egg-shaped, elongated along mesenteries, with ca. 15-20 simple or slightly branched muscular processes on each side (Fig. 2E View Figure 2 ). Others: existence of siphonoglyph unknown because of the contracted state of the specimen. Each with one tentacle from each endo- or exocoels. Tentacular circular muscle indistinct (Fig. 2C View Figure 2 ), and longitudinal muscle distinct, ectodermal (Fig. 2D View Figure 2 ). Mesoglea thickest in body wall,> 200 μm in thickness in some parts, and comparatively thick in physa and mesenteries, but thinner in parietal muscles and tentacles (Fig. 2C-E View Figure 2 ). Nemathybomes sunk into mesoglea. Marginal sphincter muscle and basilar muscle absent (Fig. 2G View Figure 2 ). Gametogenic tissue not attached to retractor muscles, distinct, but no mature gametocytes observed in our specimen (Fig. 2F View Figure 2 ). Cnidom. Basitrichs, spirocysts, and microbasic p -mastigophores. See Fig. 3A-E View Figure 3 and Table 4 View Table 4 for sizes and distributions of cnidae on this study.

Derivation of Japanese name.

see the derivation of genus name.

Remarks.

This specimen from Amami Oshima Island resembled the features of Edwardsianthus pudicus as stated by England (1987); he redescribed this species as Edwardsianthus pudica (Klunzinger, 1877), but the appropriate name is Edwardsianthus pudicus following nomenclatural rules (ICZN 31.2 and 34.2; Ride et al., 1999), as in WoRMS (Daly & Fautin, 2021). England (1987) redescribed E. pudicus in detail and designated this species as the type of Edwardsianthus England, 1987. England (1987) mentioned that E. pudicus had a large body, reaching 200 mm in length and 15 mm in width, a thick walled scapus with easily stripped periderm, scattered small nemathybomes, long slender tapered tentacles, swelled mouth, extremely developed and diffused retractor muscles composed of 70-90 muscular processes, well-developed parietal muscle with 20-30 simple or slightly branched processes, and dioecious gametogenic tissue. These features almost completely correspond to the specimen obtained in this study. The tentacles being translucent purple or magenta-pink in color (England, 1987) were also similar to the tentacles and capitulum of our specimen. Moreover, E. pudicus inhabits a broad area of the Indo-Pacific region (Fautin, 2013; Daly & Fautin, 2021), so it is not unexpected to find this species in Japanese waters.

Kingdom	Animalia
Phylum	Cnidaria
Class	Anthozoa
Order	Actiniaria
Family	Edwardsiidae
Genus	Edwardsianthus