Melithaea sagamiensis, Matsumoto, Asako K. & van Ofwegen, Leen P., 2015

Matsumoto, Asako K. & van Ofwegen, Leen P., 2015, Melithaeidae of Japan (Octocorallia, Alcyonacea) re-examined with descriptions of 11 new species, ZooKeys 522, pp. 1-127 : 30-31

Taxon classification Animalia Alcyonacea Melithaeidae

Melithaea sagamiensis sp. n. Figures 75 a–b, 76, 77, 78, 79, 80, 81, 86

Material examined.

Holotype RMNH Coel. 41929 (AKM 840a), East of Jogashima Spur, 35°03.52'N, 139°37.43'E - 35°04.17'N, 139°37.52'E, 397-286 m, R/V Tansei-maru, KT07-31, st.8, coll. A.K. Matsumoto, 25 November 2007; paratypes: ZMUC ANT-000657, Sagami Bay, Okinose, 200 fms (286-366 m), Coll. Mortensen, 1 July 1914; ZMUC ANT-000660, same data as ZMUC ANT-000657; RMNH Coel. 41930 (AKM 243), South of Mera-se-minami Knoll, Sagami Bay, 34°54.8'N, 139°39.7'E - 34°54.8'N, 139°39.9'E, 312-348 m, R/V Shinyo-maru, St. 10, coll. A.K. Matsumoto, 18 October 2003; RMNH Coel. 41931 (AKM 244), same data as RMNH Coel. 41930; RMNH Coel. 41932 (AKM 247), South of Mera-se Minami Knoll, 34°54.8'N, 139°39.7'E - 34°54.8'N, 139° 39.9E, 315-365 m, R/V Shinyo-maru, coll. A.K. Matsumoto, 18 October 2003; RMNH Coel. 41933 (AKM 593), Entrance of Otsuchi-bay, Iwate Prefecture, 39°21.858'N, 141°59.972'E, 65.6 m, R/V Yayoi, 1 m biological dredge, coll. A.K. Matsumoto, 12 September 2005; RMNH Coel. 41934 (AKM 835), Off Sendai, Miyagi Prefecture, depth over 100 m, trawl, coll. Hagihara, June 2007; RMNH Coel. 41935 (AKM 1605), West off Izu-Oshima, Sagami Sea, 410-440 m, R/V Hakuho-maru, KH-78-05, st. BS8, 2 m S.-A. beam trawl, coll. S. Ohta, 9 December 1978; BMNH 62.7.16.62(61?), off Okushiri Is., 3 miles off shore, Sea of Japan, 41°59'N, 138°30'E, 25-30 feet.

Description.

The holotype (RMNH Coel. 41929) consists of a number of branches probably belonging to one colony broken up while collecting (Fig. 75a). The largest frag ment is 2.8 cm long. A holdfast or anastomoses are not present. The polyps are situated on one side of the colony. The calyces are dome-shaped, about 0.5 mm high and 1 mm wide; most polyps are retracted. Points with slightly bent spindles up to 0.25 mm long, distal end with more developed tubercles (Fig. 76a). Collaret with bent spindles up to 0.40 mm long, middle part with more developed tubercles (Fig. 76b). Tentacles with platelets, the larger ones crescent-shaped (Fig. 76c). These platelets are up to 0.15 mm long and have almost no tuberculation. Pharynx with straight spiny rods, up to 0.05 mm long (Fig. 76d). Coenenchyme with capstans 0.05-0.07 mm long, unilaterally spinose spindles (Fig. 77b), small clubs of the same length as the capstans, and spindles 0.10-0.20 mm long (Fig. 77a); all with simple tubercles. The calyces with additional leaf clubs, up to 0.15 mm long (Fig. 76e).

Color.

White, all sclerites colorless.

Variation.

The paratypes are also fragmented. RMNH Coel. 41930, ZMUC ANT-000657 and ZMUC ANT-000651 are also white. ZMUC ANT-000660, RMNH Coel. 41931 and RMNH Coel. 41932 are yellow with yellow sclerites. BMNH 62.7.16.62(61?), RMNH Coel. 41934 and RMNH Coel. 41933 came from northern Japan, all three being red and from shallower depth. RMNH Coel. 41931 has somewhat more developed sclerites (Figs 78, 79).

Distribution.

Pacific side of Japan; Sagami Bay, off Sendai (Miyagi Prefecture), Otsuchi Bay (Sanriku, Iwate Prefecture); and Sea of Japan side, off Okushiri Is. (Fig. 86).

Etymology.

The species is named after the type locality, Sagami Bay.

Remarks.

We included BMNH 62.7.16.62(61?) in Melithaea sagamiensis sp. n. despite its slightly different sclerites (Figs 80, 81). We were not certain about the collection number, hence the “62(61)?”.