Calcigorgia herba sp. nov.

urn:lsid:zoobank.org:act: D44ADB76-6A55-466F-B41F-1123D3C34534

Figs 1–7; Table 1

Diagnosis

Calcigorgia colonies scantly branched, with long smooth stem. Polyps in alcohol-preserved material up to 3 mm high and up to 2 mm wide, crowded in distal parts of colonies, arranged irregularly on the surface of the colony. Polyp body wall cylindrical in shape and with smooth surface. Polyp tentacles with scales, warty rods and clubs, poorly developed clubs with leafy processes on head, spindles, capstans (8-radiate) and ovals. Polyp body walls with warty clubs, club-like warty spindles, warty spindles, poorly developed clubs with leafy processes on head, ovals, and capstans (8-radiate). Coenenchyme with capstans (8-radiate) and ovals.

Etymology

The specific epithet ‘herba’ is due to a shape of colonies similar to a plant with a stalk in the form of a hollow straw and with small flower-like protrusions reminiscent of ears of corn or tussocks.

Material examined

Holotype SEA OF OKHOTSK – Kurile Islands • 135 × 13 mm; Matua Is.; expedition of PFRC, NSCMB, and ZIN RAS on RV Tikhookeansky, station 306, sample 895; 48°01′ N, 153°22′ E; depth 100 m; 18 Aug. 1987; V. Lukin leg.; dredged; MIMB 20744.

Paratype SEA OF OKHOTSK – Kurile Islands • 159 × 9 mm; Matua Is.; expedition of PFRC, NSCMB, and ZIN RAS on RV Tikhookeansky, station 306, sample 895; 48°01′ N, 153°22′ E; depth 100 m; 18 Aug. 1987; V. Lukin leg.; dredged; MIMB 20745 .

Additional material

SEA OF OKHOTSK – Kurile Islands • 1 specimen; Rikord Str.; cruise on RV Tikhookeansky; 47°18′ N, 152°34′ E; depth 100 m; 18 Jul. 1987; S. Grebelniy leg.; dredged; MIMB 20684 • 1 specimen; Urup Is.; station 420; 46°19′ N, 150°42′ E; depth 100 m; 12 Sept. 1973; MIMB 20688 • 1 specimen; Ketoy Is.; cruise on RV Tikhookeansky; 47°23′2′′ N, 152°39′4′′ E; depth 200 m; 18 Aug. 1987; S. Grebelniy leg.; MIMB 20694 • 1 specimen; Urup Is.; cruise on RV Tikhookeansky; 46°19′ N, 150º42′ E; V. Lukin leg.; MIMB 20709 • 1 specimen; Diana St., between Simushir Is. and Ketoy Is.; cruise on RV Tikhookeansky, station 289, sample 846; 47°15′8′′ N, 152°28′1′′ E; depth 75 m; 17 Aug. 1987; MIMB 20746 • 1 specimen; Rasshua Is.; cruise on RV Tikhookeansky, station 300, sample 877; 48°01′ N, 153°22′ E; depth 100 m; 12 Aug. 1987; MIMB 20747 • 2 specimens; Ketoy Is.; cruise on RV Tikhookeansky; 47°23′2′′ N, 152°39′4′′ E; depth 200 m; 18 Aug. 1987; S. Grebelniy leg.; MIMB 20748 • 1 specimen; Rasshua Is.; cruise on RV Tikhookeansky, station 300; 47°49′ N, 153°00′9′′ E; depth 100 m; 19 Aug. 1987; V. Lukin leg.; MIMB 20749 .

Description

Holotype

Colony scantly branched (Fig. 1A), with long smooth stem. Polyps crowded in the distal part of colony, arranged irregularly on the surface of the colony (Fig. 1F).

Colony 135 mm high and 13 mm wide (Fig. 1A). Polyps up to 3 mm high and 2 mm wide. Polyp body wall cylindrical in shape, with smooth surface; tentacles folded over polyp, partly retracted to inside (Fig. 1F).

Coenenchyme 0.5 mm thick and consists of two layers, a 0.4 mm thick outer layer, with smooth surface, and a very thin inner layer. Axis with concentric layers; no mineralization observed. Sclerites unordered in tentacles, polyp body wall and coenenchyme.

Tentacles contain small warty rods, scales, warty spindles, clubs, capstans and ovals. Warty spindles, up to 0.11 mm long (Fig. 2A). Scales, up to 0.11 mm long, flattened, with notched edges (Fig. 2B). Warty spindles, up to 0.22 mm long, with tall and asymmetrically developed processes (Fig. 2C). Warty clubs mainly 0.12–0.2 mm long, with plump warty heads and straight warty handles (Fig. 2D). Smaller clubs, up to 0.15 mm long, poorly developed (Fig. 2E). Their handles short and thick, blunt, bearing small crowded warts; the heads consist of notched leafy processes (Fig. 2E). Club-like spindles, up to 0.23 mm long, with some accumulation of processes on one end (Fig. 2F) and warts tending to be girdled. Capstans (8-radiate), usually up to 0.12–0.14 mm long, not numerous (Fig. 2G). Some well calcified capstans, up to 0.16 mm long, transitional to warty ovals. These ovals, up to 0.19 mm long, bear crowded warts tending to be conjunct (Fig. 2H).

Polyp body wall with warty clubs, mainly 0.15–0.18 mm long, with plump head consisting of warty processes (Fig. 3A). Shorter clubs, up to 0.16 mm long, poorly developed, with notched leafy processes on heads; handles of short clubs thick and covered with small warts (Fig. 3B). Longer clubs transitional to club-like spindles, up to 0.16 mm long, with some accumulation of warts on one end (Fig. 3C). Plump spindles, up to 0.21 mm long, straight, with warts tending to be girdled (Fig. 3D). Short clubs also coincide with ovals, mostly 0.14–0.16 mm long, densely covered by unordered warts (Fig. 3E), and capstans, mostly 0.14–0.16 mm, ornamented with girdled warts (Fig. 3F). Clubs, spindles and ovals abundant. Capstans not numerous.

Outer coenenchyme layer with numerous 8-radiate capstans, mostly 0.15–0.16 mm long (Fig. 4A). Massive capstans, up to 0.18 mm long, with very developed warts, transitional to ovals, up to 0.18 mm long, bearing densely crowded processes (Fig. 4B). Internal layer of coenenchyme contains weakly calcified capstans, up to 0.15 mm long, of same shape as those in outer layer.

Paratype and variations

Paratype MIMB 20745 colony shape and size similar to holotype – 159 mm high and 9 mm wide (Fig. 1B). Polyp body wall smooth and cylindrical; tentacles folded over the polyp and partly retracted to the inside (Fig. 1G). Sclerites composition (Figs 5–7) coincides with that in holotype (Figs 2–4). The only difference is some greater calcification of sclerites in polyp body wall of paratype – its warty clubs (Fig. 6A) and poorly developed clubs (Fig. 6D) with more wide heads than those in holotype (Fig. 3 A–B). Club-like spindles in paratype slightly longer – up to 0.25 mm in polyp tentacles (Fig. 6B) vs 0.23 mm in holotype (Fig. 2F). Short, poorly developed clubs and ovals longer in polyp body wall of the paratype – up to 0.18 mm (Fig. 6 D–E) vs 0.16 mm in holotype (Fig. 3B, E). Plump spindles of same size numerous in both paratype (Fig. 6C) and holotype (Fig. 3D). The coenenchyme of the paratype double-layered as in holotype, with 8-radiate capstans, up to 0.16 mm long (Fig. 7A), and well calcified ovals up to 0.18 mm long (Fig. 7B).

Colour

In alcohol-preserved material: polyps and coenenchyme creamy; colony axis black or deeply brown, sclerites colourless.

Remarks

The most obvious distinctive characters of C. herba sp. nov., differing from characters of other known members of the genus, are the shape of colony (with slender smooth stem and polyps crowded in the terminal part of the colony) and the presence of two different types of clubs among the sclerites. One of these types, the poorly developed clubs with notched leafy processes on their heads and short warty handle, has not been described before in any of the known species of the genus (Figs 2E, 3B, 5F, 6D, Table 1). Moreover, only C. herba sp. nov. has warty rods along with scales in the tentacles (Fig. 2A, Table 1) and two types of sclerites in the coenenchyme – 8-radiate capstans and ovals (Figs 4 A–B, 7A–B, Table 1).

C. herba sp. nov. coincides with С. lukini sp. nov. having ovals and capstans in the tentacles but the last has no clubs in the polyp body (Table 1). The composition of the sclerites in the polyp body wall of C. herba sp. nov. coincides with that of C. spiculifera, C. matua and C. simushiri as all these species have warty clubs, spindles, capstans and ovals in that part of polyp (Table 1). However, only C. herba sp. nov. has poorly developed leafy clubs with thick warty handles in that part of polyp (Figs 3B, 6D, Table 1). Furthermore, C. simushiri has long-handled clubs that are missing in C. herba sp. nov. (Table 1). Thus, the morphology of polyps and composition and size of sclerites in the polyp and coenenchyme distinguish C. herba sp. nov. from all previously described representatives of the genus.

Distribution

This species is known for certain from the Kurile Islands, Sea of Okhotsk, Northwestern Pacific, between 75 and 200 m depth.