Briareum stechei ( Kuekenthal , 1908)

Samimi-Namin, Kaveh & van Ofwegen, Leen P., 2016, Overview of the genus Briareum (Cnidaria, Octocorallia, Briareidae) in the Indo-Pacific, with the description of a new species, ZooKeys 557, pp. 1-44 : 11-12

Taxon classification Animalia Alcyonacea Briareidae

Briareum stechei ( Kuekenthal, 1908) Figures 11 C–G, 12, 13, 14, 15, 16, 17, 18, 26 C–D

Erythropodium stechei Kükenthal, 1908: 19 (Banda); 1919: 38.

Suberia excavata Nutting, 1911: 14, pl. 3 fig. 2, 2a, pl. 11 fig. 4 (Ambon).

Solenopodium excavatum ; Kükenthal 1919: 42; 1924: 13; Stiasny 1937: 12, Pl. 1 figs 4-5, fig. C (re-examination type); Verseveldt 1940: 32-37.

Solenopodium stechei var. novaepommeraniae Kükenthal, 1919: 901 (New Britain); 1924: 13.

Solenopodium stechei ; Aurivillius 1931: 9 (Timor); Stiasny 1937: 17, pl. 1 figs 1-3, fig. E (re-examination syntype ZMB 5828); Macfadyen 1936: 67 (Australia); Tixier-Durivault 1970: 325 (New Caledonia).

Briareum excavatum ; Benayahu 1997: 238 (Guam); Erhardt and Baensch 2000: 220 (life image, RMNH Coel. 24018); Benayahu et al. 2004: 551, fig. 3 (Taiwan).

Briareum stechei ; Grasshoff 1999: 6, fig. 5 (New Caledonia).

Briaeum [sic] excavatum Benayahu 2002: 20 (Ryukyu Archipelago, Japan).

Briareum cf. stechei ; Alderslade and McFadden 2007: 41, fig. 10B.

Material examined.

ZMB 5828, holotype Erythropodium stechei : Banda Island (Moluccas), litoral, leg. Steche; ZMB 5816, Ambon (Moluccas), litoral, leg. Steche; ZMB 5016, 5854, holotype Solenopodium stechei var. novaepommeraniae , Neupommern, litoral, leg. Schoede; ZMA 3410, syntype Briareum excavatum ; Siboga Exped. stat. 142, Maluku, anchorage off Laiwui, depth 23 m, Hensen vertical net, tow net, dredge; ZMA 3489, same data as ZMA 3410; RMNH Coel. 5837, Indonesia, Laiwui, Obi Major St. 142 Siboga expedition (id. Solenopodium excavatum ); RMNH Coel. 18416, Indonesia, Celebes, Westside Samalona, 18 m depth, 18 September 1980, coll. H. Moll (id. Briareum excavatum ); RMNH Coel. 41416, Indonesian-Dutch Snellius II Exp., Sta. 4.052, NE coast of Sumba, E of Melolo, 09°55'S, 120°45'E, edge of extensive, gently sloping reef flat, SCUBA diving, snorkelling, depth 10-15 m, 13/14 September 1984; RMNH Coel. 41417, Indonesian-Dutch Snellius II Exp., Sta. 4.222, northeast Taka Bone Rate (tiger islands), south of Pulau Tarupa Kecil, rectangular dredge, depth 58 m, 06°31.5'S, 121°08.0'E, sandy bottom with gorgonians antipatharians, sponges, 14 October 1984; RMNH Coel. 41418, Buginesia Progr. UNHAS- NNM 1994/1995, Sta. SUL.SAM S, Indonesia, southwest Sulawesi, Spermonde Archipelago, south of Samalona Isl. (= 7.5 km W of Ujung Pandang = Makassar), 5°07'S, 119°20'E; coral reef; SCUBA diving, 31 May 1994, coll. B.W. Hoeksema; RMNH Coel. 41419, BUN.06, Indonesia, North Sulawesi, Tanjung Totrowitan main coast, steep slope fringing reef, 01°45'N 124°58.500'E, SCUBA diving. 6 May 1998, coll. B.W. Hoeksema and L.P. van Ofwegen; RMNH Coel. 24018, Indonesia, Banda Island, depth 12 m, 30 September 1998, coll. H. Erhardt, dry material, det. L.P. van Ofwegen (id. Briareum excavatum ); RMNH Coel. 41420-21, RUM.20, Indonesia, Moluccas, Ambon, Hitu, north coast, Hitulama; 20 November 1990, coll. C.J.H.M Fransen; RMNH Coel. 41422, BUN.14, Sta.14: Indonesia, N. Sulawesi, Bunaken Park, NE Bunaken Island, steep slope, 124°46'30"E 01°36'30"N, SCUBA diving. 10. May 1998; Coll. B.W. Hoeksema; RMNH Coel. 41423, CEB.08, Philippines, Cebu Strait, west of Bohol, north side of Cabilao Island, Cabacungan Point, 9°51.55'N 123°45.95'E, reef edge with dense coral cover, overhanging wall with caves, snorkelling and SCUBA diving, 11 November 1999, coll. L.P. van Ofwegen; RMNH Coel. 41424, BER.16, Indonesia, northeast Kalimantan, Berau Islands, Maratua Island, NE-side, 2°17.487'N 118°35.483'E, SCUBA diving, 10 October 2003, depth 28 m, coll. L.P. van Ofwegen and M. Slierings; RMNH Coel. 38607, Sabah, Layang Layang atoll, outer reef on east end of atoll, 07°22.69'N 113°52.23'E, depth 10 m, 13 October 2006 (0CDN 9322-R); RMNH Coel. 39998, Palau, Angaur, northeast side of island, reef sloping 30° to sandy slope below 200 ft., reef top, rock, depth 8 m, 06°55.36'N 134°08.68'E, 21 June 2008 (0CDN9600-T); RMNH Coel. 40023; Palau, SW Islands, Helen Reef lagoon, reef of conservation area main lagoon marker, lagoon patch reef, large with shallower reef area, sand/rubble/coral patches, 16 September 2008, depth 14 m, lagoon Pinnacle, Rock, 02°52.860'N 131°46.510'E (0CDN9778-N); RMNH Coel. 40078, Palau, Velasco Reef north of Kayangel, central ‘lagoon’ area; pinnacle/large patch reef 15 m depth in mid ‘lagoon’ of Velasco reef Lagoon pinnacle, rock depth 15 m, 08°17.290'N 134°38.200'E; 26 June 2009 (0CDN9988-Q); RMNH Coel. 41425, Exp. Indonesia, Ternate - Halmahera. 2009, TER.15, Indonesia, Halmahera, Tidore, Cobo, 0°45.312'N 127°24.397'E, 01 November 2009; RMNH Coel. 40884, PAL.168, Republic of Palau, Koror, Wonder Channel, 7°10.869'N 134°21.612'E, depth 19.6 m, 21 May 2010, coll. C.S. McFadden; RMNH Coel. 40885, PAL.173, Republic of Palau, Koror, Wonder Channel, 7°10.869'N, 134°21.612'E, depth 18.8 m, 21 May 2010, coll. C.S. McFadden; RMNH Coel. 40886, PAL.218, Republic of Palau, Koror, Pinchers, 7°20.402'N 134°25.682'E, depth 7.3 m, 22 May 2010, coll. C.S. McFadden; RMNH Coel. 40887, PAL.314, Republic of Palau, Koror, Turtle Cove, 7°05.078'N 134°15.730'E, depth 52 m, 24 May 2010, coll. C.S. McFadden; RMNH Coel. 41445, CEB.05, Philippines, Cebu Strait, W of Bohol, west side of Cabilao Island, south side fish sanctuary, 9°52.60'N 123°45.61'E, dense algae-covered reef flat to 4 m, vertical wall with caves to 45 m, SCUBA diving, 8 November 1999, coll. L.P. van Ofwegen; RMNH Coel. 41448, BER.03, Indonesia, northeast Kalimantan, Berau Islands, Derawan Island, southern side (jetty Derawan Dive Resort), 2°17.055'N 118°14.813'E, SCUBA diving, 22 October 2003, depth 20 m, coll. L.P. van Ofwegen and M. Slierings; RMNH Coel. 41615, TER.32, Indonesia, Pulau Pulau Gura Ici, east Pulau Gura Ici, 0°1.288'S, 127°14.287'E, 10 November 2009, depth 18 m, coll. B.T. Reijnen.

Diagnosis.

Cortex with straight or bent spindles with simple or complex tubercles mostly arranged in transverse rows (Figure 12A). These cortex sclerites are 0.10-0.75 mm long. The medulla additionally has branched bodies with simple or complex tubercles (Figure 12B). These sclerites are slightly shorter, up to 0.60 mm long. Sclerites of surface layer colourless, interior sclerites magenta.

Remarks.

The sclerites are most like those of Briareum violaceum but in that species many spindles are longer than the longest of Briareum stechei .

Nutting (1911) apparently was not aware of Kükenthal’s earlier ( 1908) description of Erythropodium stechei ; actually, at first he did not compare his new species with any previously described one. Later, Kükenthal (1919) noticed the resemblance with his Erythropodium stechei , now in the genus Solenopodium Kükenthal, 1916a, and put it in the synonymy of that species with a question mark as he did not re-examine Nutting’s material. Stiasny (1937) re-examined type material of both Solenopodium stechei and Solenopodium excavatum and kept them as separate species. According to him, Solenopodium excavatum differs in having higher calyces (Figure 11G), and by lacking calyx sclerites and “dendritic” sclerites in the interior. Verseveldt (1940: 37) was the last to compare these two species and noted no less than six aspects of difference between them, however, he did not re-examine the type material of Briareum stechei . We present sclerites images of the types of the two species (Figures 12-13). We consider the differences mentioned by previous authors as intraspecific variation, similar to that as observed in Briareum hamrum , and therefore we synonymize Briareum excavatum with Briareum stechei .

Kükenthal (1908) described Erythropodium stechei from Banda only. In the Berlin Museum, ZMB 5828 (Fig. 11C), material from Banda, and ZMB 5816 (Figure 11D), material from Ambon, are present, both labelled type. It looks like these specimens represent the same material. It is puzzling to us why Ambon is now mentioned as the locality of ZMB 5816.

Solenopodium stechei var. novaepommeraniae is also represented by two collection numbers in Berlin, ZMB 5016 (Figure 11E) and ZMB 5854 (Figure 11F), here obviously the original material was split into two.

Morphological variation.

To show the enormous variation in sclerites we have made SEM images of two specimens from Palau (RMNH Coel. 40023) collected at the same locality. One of them shows almost smooth spindles (Figs 14-15) while the other, like the type, has none at all (Figs 16-17). RMNH Coel. 41421 has peculiar bent and smooth sclerites (Figure 18).

Distribution.

Coral Triangle, Australia (Low Isles), Guam, Taiwan.