Stylaster verrillii (Dall, 1884)

Cairns, Stephen D. & Lindner, Alberto, 2011, A Revision of the Stylasteridae (Cnidaria, Hydrozoa, Filifera) from Alaska and Adjacent Waters, ZooKeys 158, pp. 1-88 : 32-35

Stylaster verrillii (Dall, 1884) Figs 11B, F, H15 A–M

Allopora verrillii Dall, 1884: 111-113.- Fisher 1931: 391-392.

Allopora moseleyi Dall, 1884: 113.- Fisher 1931: 391-392.

Allopora verrilli : Fisher 1938: 521-522, pl. 54, fig. 3, pl. 57, pl. 76, figs 5-6.- Naumov 1960: 567, text-fig. 411.

Stylaster (Allopora) norvegicus forma pacifica Broch 1936: 52, text fig. 15c-d (in part: record from Snake Island, Strait of Georgia, British Columbia).

Stylaster (Allopora) verrillii : Broch 1942: 6.

Allopora norvegicus pacifica .- Lowenstam 1964: 382 (mineralogy).

Stylaster verrillii : Cairns 1983b: 429.- Heifetz 2002: 22 (listed).- Wing and Barnard 2004: 11, 28, fig. 31.- Heifetz et al. 2005: 134, 137.- Stone and Shotwell 2007: 108 listed).- Brooke and Stone 2007: 522, fig. 2B.-Jameison et al. 2007: 224 (listed).- Lindner et al. 2008: 3, supplemental Table S1 (phylogeny and DNA sequences).

Stylaster?norvegicus .-Jameison et al. 2007: 224 (listed).

Type material.

Allopora verrillii : 5 badly worn, dry, female syntypes, the largest 44 mm in diameter (USNM 4193, Fig. 11H). All branches are eroded from the colony, thus resembling an encrusting colony. Collected together with four dry topotypic specimens (USNM 8850).

Type locality.

Chika Island, Akutan Pass, near Unalaska, Aleutian Islands, on beach.

Allopora moseleyi : Holotype, 1 small (18 mm) dry colony, USNM 6851 (Fig. 11F).

Type locality.

Kiska Harbor, Kiska Island, Aleutian Islands, on beach.

Material examined.

Types of the two species; Alb-4777, 52°11'N, 179°49'E, 95 m, 5 June 1906, 1 female, 1 male, 1 indet., and SEM stub 1501, USNM 53394 and 76524 (mentioned by Fisher 1938); unnumbered Albatross station, Sucia Islands, near San Juan Island, Washington, 16 Sep 1890, 2 female, 11 male colonies, and SEM stub 1513, USNM 76526-28 (mentioned by Fisher 1938); Delta 5622, 51°57'36.54"N, 176°49'58.32"W, 140 m, 24 Jul 2002, 1 male, and SEM stub 1503, USNM 1123299; Delta 5625, 51°57'42"N, 176°50'01"W, 155 m, 25 Jul 2002, 1 male, USNM 1027819; Patricia Lee, 51°53.44'N, 179°47.7'E, 298 m, 1 indet., AB00-41b; Sea Storm 122, 52°02'49"N, 179°25'18"E, 143 m, 13 Jul 2002, 2 female colonies in alcohol, USNM 1123058 (attached to Distichopora borealis, USNM 1123061); Sea Storm 123, 52°10'53"N, 179°37'02"E, 124 m, 13 Jul 2002, 3 female, 2 male, 1 indet., USNM 1123053, 1123056; Sea Storm 129, 51°52'24"N, 179°44'07"E, 84-93 m, 14 Jul 2002, 1 male in alcohol, USNM 1123051; Sea Storm 155, 52°38'43"N, 172°27'27"W, 393 m, 22 Jul 2002, 1 female, USNM 1122763; Vesteraalen 941-40, 52°53'N, 169°59'W, 0-62 m, 11 Jun 1994, 1 female, USNM 96260; Vesteraalen 941-151, 52°10'36"N, 179°43.7'E, 87-92 m, 10 Jul 1994, 1 male, and SEM stub 1502, USNM 1123537; south of Semisopochnoi Islands, 366 m, 1 indet., USNM 88368; Ralston Island, near Juneau, depth unknown, 1 indet., AB04-21; Stubbs Island, BC, depth unknown, 2 indet., AB02-02; Wooden Island, AK, depth unknown, 2002, 1 dry, AB02-150b; Middle Cross Sound, AK, 15-21 m, 27 Jul 1978, 1 indet., AB78-120a; North Pass, Lincoln Island, AK, depth unknown, 2 indet. in alcohol, AB05-37.

Description.

Colonies arborescent, dichotomously branching to form a three dimensional bush; branch tips blunt to slightly clavate, 3.0-4.5 mm in diameter. Largest colony (USNM 1027819, Fig. 11B) 3.5 cm tall, 7.0 cm wide, and attached by a basal branch 11 mm in diameter. Colonies usually attached to stones or bivalve shells. Coenosteum reticulate-granular in texture, coenosteal strips 52-55 µm wide, separated by thin slits 10-13 µm wide. Strips covered with small (8-10 µm in diameter) spines, occurring 4-5 across width of a strip, conferring a fine, granular or "sugary" texture. Coenosteal papillae common. Most colonies infested with spionid worms and their characteristic binary tubes (Fig. 15A, K). Coenosteum light orange.

Cyclosystems occur on all sides of branches, circular, and 1.0-1.2 mm in diameter. Gastropore circular and small (0.25-0.30 mm in diameter). Gastropore tubes funnel-shaped near surface but cylindrical adjacent to gastrostyle, straight, and often quite long in thick branches. Ring palisade robust near gastrostyle tip, composed of squat, clavate elements about 40 µm in diameter. Gastrostyles lanceolate to elongate (up to 1.5 mm, Fig. 15H), with a pointed tip; gastrostyles covered with anastomosing, longitudinal, spiny ridges, the spines quite long (up to 65 µm in length) and sharp.

Cyclosystems flush to only slightly raised above coenosteum. Dactylotomes 0.07-0.10 mm in width, sometimes becoming obsolete within a system by infilling of the axial slit, resulting in just an apical pore. Dactylostyles robust (Fig. 15F, M), composed of tall slender cylindrical elements up to 60 µm in height and 10-15 µm in diameter. Range of dactylopores per cyclosystem 5-10 (n = 50, average = 7.10 (σ=1.16), and mode = 7). Pseudosepta triangular; diastemas rare.

Female ampullae primarily internal (Fig. 15K), with only a slight superficial swelling; internal diameter of ampullae 0.7-0.8 mm. Efferent pores of female ampullae never observed. Male ampullae (Fig. 15H, L) also primarily internal, visible on surface only as small dimples about 0.4 mm in diameter; internal cavity diameter 0.3-0.5 mm.

Remarks.

Stylaster verrillii is similar to Stylaster venustus (Figs 16 A–I, 17 F–G), but differs in having orange, bushy coralla (not pink to purple planar colonies, Fig. 17G); larger cyclosystems (1.0-1.2 mm vs 0.7-0.9 mm in diameter); larger diameter and blunt distal branches; triangular (not rectangular, Fig. 16B) pseudosepta; and straight-sided gastropore tubes (not hemispherical, Fig. 16B)(also see Table 2). Both species are confined to relatively shallow water and have overlapping distributions off British Columbia and Washington. According to the ICZN (1999) article 31.1.3, the original spelling verrillii should be preserved in preference to verrilli.

Distribution.

Known from Kiska Harbor, Aleutian Islands to Sucia Islands, Washington; 21-393 m, although most records between 60-155 m.