Melithaea corymbosa ( Kuekenthal , 1908)

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 : 7-12

Taxon classification Animalia Alcyonacea Melithaeidae

Melithaea corymbosa ( Kuekenthal, 1908) Figures 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27

Acabaria corymbosa : Kükenthal 1908: 197; 1909: 70, figs 81-83, pl. 6 fig. 31 (Misuki (= Misaki), Japan); Kükenthal 1919: 187; 1924: 81; Aurivillius 1931: 24 (Sagami Bay); Hickson 1937: 177.

Material examined.

Syntype ZMB 5814, Misaki (Japan), coll. Doflein, 1904/05; previously unidentified museum material: ZMUC ANT-000587, Okinose, Sagami Bay, Japan, 100 fms (143-183 m), coll. Dr. Th. Mortensen, 26 June 1914; ZMUC ANT-000588; Sagami Bay, Japan, 80-120 fms (114-219 m), coll. Dr. Th. Mortensen, 6-19 June 1914; ZMUC ANT-000590, Okinose, Sagami Sea, 100 fms (143-183 m), coll. Dr. Th. Mortensen, 15 June 1914; ZMUC ANT-000646, Off Nagasaki, 32°15'N, 128°12'E, 90 fms (165 m), coll. Dr. Th. Mortensen, 15 May 1914; ZMUC ANT-000654, Okinose, Sagami Sea, 100 fms (143-183 m),, coll. Dr. Th. Mortensen, 23 June 1914; ZMUC ANT-000659, Okinose, Sagami Bay, 200 fms (286-366 m), coll. Dr. Th. Mortensen, 1 July 1914; ZMUC ANT-000661, same data as ZMUC ANT-000654; ZMUC ANT-000650, Off Misaki, Sagami Bay, ca.250 fms (ca.358-457 m), coll. Dr. Th. Mortensen, 10 June 1914; UMUTZ-CnidG-15, Japan; UMUTZ-CnidG-17, Gorgonian cave at Koajiro, Misaki, Sagami Bay, 16 July 1897; UMUTZ-CnidG-23 (G-23a), same data as UMUTZ-CnidG-17; UMUTZ-CnidG-268 (G-37d), Misaki, Sagami Bay, coll. K. Kinoshita, summer 1906; UMUTZ-CnidG-41, Awa Kominato, Boso Peninsula, Chiba Prefecture, coll. sp. no. 78, April 1885; UMUTZ-CnidG-271 (G-41b), same data as UMUTZ-CnidG-41; UMUTZ-CnidG-199, Sengenzuka-Aoyamadashi line, Sagami Bay, 100 hiro (143-151 m), coll. H. Matsumoto and H. Chiba, 20 July 1913; RMNH Coel. 41902 (AKM 223), South of Mera-se bank, Sagami Bay, 34°59.6'N, 139°41.1'E - 34°59.7'N, 139°41.1'E, 81-78 m, R/V Shinyo-maru, St.1, coll. A.K. Matsumoto, 17 October 2003; AKM 225, same data as RMNH Coel.41902; AKM 242, South of Mera-se Minami knoll, 34°54.8'N, 139°39.7'E - 34°54.8'N, 139°39.9'E, 348-312 m, R/V Shinyo-maru, coll. A.K. Matsumoto, 18 October 2003; AKM 245, South of Mera-se bank, Sagami Bay, 34°54N 139°39E, 315-365m, R/V Shinyo-maru, coll. A.K. Matsumoto, 18 October 2003; AKM 246, South of Mera-se Minami knoll, 34°54.2'N, 139°39.9'E - 34°54.3'N, 139°39.3'E, 348-312 m, R/V Shinyo-maru, coll. A.K. Matsumoto, 18 October 2003; AKM 248, same data as AKM245; AKM 253, Sagami Bay, 33°26.3'N, 139°42.3'E - 33°26.5'N, 139°42.0'E, 157-172 m, R/V Shinyo-maru, K-32, St. 18, coll. A.K. Matsumoto, 21 October 2003; AKM 299, Sagami Sea, 33°27'N, 139°42'E, 200-211 m, R/V Shinyo-maru, coll. A.K. Matsumoto, 21 October 2003; RMNH Coel. 41903 (AKM 513), Otsuki, Tosa, Kochi Prefecture, 132°50.44'E 32°37.66'N, - 132°47.88'E 32°37.56'N, 114 m, local fishermen’s boat, Kiryo-maru, st.1, coral net, coll. A.K. Matsumoto, 7 October 2004; AKM 578, off Ohakozaki cape, Otsuchi, Iwate Prefecture, 39° 21.338N 142° 00.721E, 75 m, R/V Yayoi, St. 2.3.4, coll. A.K. Matsumoto, 22 February 2005; AKM 595, entrance of Otsuchi Bay, Otsuchi, Iwate Prefecture, 39° 21.858N 141° 59.972E, 65.6 m, R/V Yayoi, St.1, coll. A.K. Matsumoto, 12 September 2005; RMNH Coel. 41904 (AKM 840b), 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; RMNH Coel. 41905 (AKM 886), Hachijo Is., Izu Isls., 33°20.9082'N, 139°41.1841'E - 33°21.0775'N, 139°40.4931'E, 213-185 m, R/V Tansei-maru, KT07-31 (Kuramochi leg.), St.14 (L-7-200), Chain Bag Dredge, coll. A.K. Matsumoto, 26 November 2007; RMNH Coel. 41906 (AKM 928), Hachijo Is., Izu Isls., 33°22.5320'N, 139°40.492'E - 33°22.3111'N, 139°40.2511'E, 202-145 m, R/V Tansei-maru, KT07-31, St.15 (L-7-100), Chain Bag Dredge, coll. A.K. Matsumoto, 26 November 2007; RMNH Coel. 41907 (AKM 949), Toshima Is., Izu Isls., 34°33.1102'N, 139°17.4102'E - 34°33.6524'N, 139°17.6725'E, 143 m, R/V Tansei-maru, KT07-31, Kuramochi leg., St.22 (L-3-100), Chain Bag Dredge, coll. A.K. Matsumoto, 27 November 2007; RMNH Coel. 41908 (AKM 1175), off Kerama Is. Okinawa Prefecture, East China Sea, 127°27.70'E - 127°27.95'E, 26°04.59'N, - 26°04.56'N, 160-153 m, R/V Tansei-maru, KT08-33 cruise, St. KR- 07, Chain Bag Dredge, coll. A.K. Matsumoto, 16 December 2008; RMNH Coel. 41909 (AKM 1176), same data as AKM 1175; RMNH Coel. 41910 (AKM 1320), off Kerama Islands. Okinawa Prefecture, East China Sea, 26°00'N, 127°12'E, 100-97 m, R/V Tanisei-maru, KT08-33, st. KR-3, coll. A.K. Matsumoto, 18 December 2008; RMNH Coel. 41911 (AKM 1321), same data as AKM 1320; AKM 1519, off Funakoshi Bay, Iwate Prefecture, 101 m, R/V Yayoi, St. 2-5, CO N, coll. A.K. Matsumoto, 26 April 2010; AKM 1525, off Oshima Is. Entrance of Otsuchi Bay and Funakoshi Bay, Iwate Prefecture, 39°22.085'N, 142°01.152'E, 97 m, by R/V Yayoi, 1 m biological dredge. coll. A.K. Matsumoto, 26 April 2010; AKM 1545, off Ohako-zaki Cape, Otsuchi, Iwate Prefecture, 86.5 m, R/V Yayoi, st. 2-2, coll. A.K. Matsumoto, 27 April 2010; RMNH Coel. 41912 (AKM 1602), South East off Taito-saki, Boso Peninsula, 35°09.31'N, 140°48.57'E - 35°09.60'N, 140°49.40'E, 311-325 m, R/V Tansei-maru, KT95-05, st. TB14, coll. S. Ohta, 26 April 1995; RMNH Coel. 41913 (AKM 1603), Okinoyama Basin, Sagami Bay, 86-88 m, R/V Tansei-maru, KT87-19, st. OKI, 1 m ORI biological dredge, coll. S. Ohta, 10 December 1987.

Re-description.

Colony bushy with anastomoses; end branches flattened (Fig. 14a). Points with slightly bent spindles up to 0.20 mm long, distal end with spines (Fig. 15a). Collaret with bent spindles up to 0.25 mm long, middle part with more tubercles (Fig. 15b). Tentacles with platelets, the larger ones crescent-shaped with irregular projections (Fig. 15c). These platelets are up to 0.17 mm long. Pharynx with straight spiny rods, up to 0.05 mm long (Fig. 15d). Coenenchyme with predominantly spindles, 0.10-0.18 mm long (Fig. 16b), with simple or complex tubercles. A few capstans and unilaterally spinose spindles also present (Fig. 13f). Calyces with thorn clubs, 0.10-0.12 mm long (Fig. 16a).

Color.

Colony red with yellow tentacles; tentacle and pharynx sclerites colorless, all others pink.

Variation.

ZMUC ANT-000587 (Fig. 14b) has a different colony shape than the syntype but the same locality, color and sclerites (Figs 17, 18). The species shows much color variation, RMNH Coel. 41902 has colorless and pink coenenchymal sclerites and yellow polyp ones. RMNH Coel. 41907 has orange coenenchymal sclerites and pink polyp ones. ZMUC ANT-000654 has colorless and pink coenenchymal sclerites, orange collaret and point sclerites and yellow tentacle ones; RMNH Coel. 41904 and RMNH Coel. 41905 show orange coenenchymal sclerites and colorless polyp ones; ZMUC ANT-000646 has a mixture of yellow and orange sclerites in both coenenchyme and polyps; RMNH Coel. 41906 is yellow with yellow sclerites. RMNH Coel. 41912 has an unique color pattern in Melithaea corymbosa , red colony with white axis. Its sclerites are also slightly different, the polyp sclerites are less tuberculate, clubs of calyces are smaller, longer ones being very scarce, and the unilaterally spinose spindles are less developed (Fig. 19). This is probably due to the preservation in formalin. RMNH Coel. 41913 has extremely well developed unilaterally spinose spindles (Fig. 20).

Distribution.

Pacific coast of Japan; Sagami Bay; Izu Isls.; Boso Peninsula (Chiba Prefecture); Otsuchi (Sanriku, Iwate Prefecture); Otsuki (Tosa, Kochi Prefecture); and East China Sea; off Nagasaki; off Kerama Is.(Fig. 27).

Remarks.

The other syntype is in Hamburg, ZMH C3299.

We included a number of specimens in Melithaea corymbosa , which show differences from the description above. Because of the limited material and rather small differences we refrain from describing them as new species. The specimens differ as follows: RMNH Coel. 41903 has a red colony color with white polyps (Fig. 14c), all coenenchymal sclerites are colorless, the axis sclerites are pink. It differs from Melithaea corymbosa in having more capstans and derivatives of capstans (Figs 21, 22). RMNH Coel. 41908 (Fig. 14d) and RMNH Coel. 41909 are white colonies with colorless sclerites. They differ from Melithaea corymbosa in having many small clubs with rounded heads (Figs 23, 24). RMNH Coel. 41910 and RMNH Coel. 41911 (Fig. 14e) have more unilaterally spinose spindles than normal for Melithaea corymbosa (Figs 25, 26). Both colonies come from the same locality but have different color patterns. RMNH Coel. 41910 is orange with white calyces and polyps; sclerites of polyps and calyces colorless, others orange; RMNH Coel. 41911 is red with orange sclerites. ZMUC ANT-000646 has an orange colony with white polyps, sclerites yellow with colorless polyp sclerites. It differs from Melithaea corymbosa in having more capstans and derivatives of capstans. In this respect it resembles RMNH Coel. 41903, from which it differs in having overall more tuberculate sclerites.