Hydroides tuberculata Imajima, 1976

Kupriyanova, Elena K., Sun, Yanan, Ten Hove, Harry A., Wong, Eunice & Rouse, Greg W., 2015, Serpulidae (Annelida) of Lizard Island, Great Barrier Reef, Australia, Zootaxa 4019 (1), pp. 275-353 : 294-296

Hydroides tuberculata Imajima, 1976

( Fig. 11 )

Hydroides tuberculata Imajima, 1976a: 132 –133, fig. 7a–j [SW Japan; description].

Hydroides tuberculata . — Imajima 1978: 53 [Izu Islands, Japan]; 1982: 44 [ Palau and Yap Islands, Micronesia]; Imajima & ten Hove 1984: 44–45 [ Truk, Ponape Island; Okinawa, experimental fouling; Lizard Island, experimental fouling, Noosa Head, Heron Island; synonymy, extensive discussion]; Bailey-Brock 1985: 210 [ Fiji]; Sun et al. 2015: 88 –91, Fig. 29 [WA, NT, Qld, Australia].

Hydroides perezi not Fauvel, 1918.— Straughan 1967a: 219 –220, Fig. 6 o [Havannah Island, Qld, see Imajima & ten Hove 1984: 44].

Hydroides brachyacantha not Rioja, 1941.— Dew 1959: 28 –29 [in part, see Imajima & ten Hove 1984: 44].

Hydroides tuberculatus .— ten Hove 1994: 108 [SW Japan]; Fiege & Sun 1999: 121–123, fig. 11A–C [South China Sea]; Kupriyanova et al. 2008: 428, 430–431, fig. 1B [Lizard Island, Qld; DNA data]; ten Hove & Kupriyanova 2009: 54 [name only]; Bailey-Brock et al. 2012: 969, 973–974, fig. 4B, C [Rongelap, Utirik, Marshall Islands]; Sun et al. 2012a [Discussion].

Material examined. AM W.198890, near Bird Islet, 14°40'S, 145°28'E, experimental fouling grid C, 7 months exposed near Bird Islet, C- 15-18-3, coll. P. Hutchings & P. Weate, det. H. ten Hove, 1981; AM W.198919 (2), lagoon drop-off between Bird Islet and South Island, stn.77 LIZ C 15-18-3, 14°42'S, 145°28'E, Jul 1978; AM W.198920, near Bird Islet, 14°40'S, 145°28'E, experimental fouling grid C, 7 months exposed near Bird Islet, C- 15-18-3, coll. P. Hutchings & P. Weate, det. H. ten Hove, 1981; AM W.16980, near Bird Islet, 14°40'S, 145°28'E, experimental fouling grid C, 7 months exposed near Bird Islet, C- 15-18-3, coll. P. Hutchings & P. Weate, det. H. ten Hove, 1981; AM W.45055, MI QLD 2406 (3); AM W.45074, MI QLD 2417; AM W.45079, MI QLD 2417 (2); AM W.45092, MI QLD 2435; AM W.45414, MI QLD 2446; AM W.45419, MI QLD 2446 (2); AM W45425, MI QLD 2447; AM W.46429, Day Reef, mid shelf of Fore Reef, 14°28'18"S, 145°31'48"E, coral rubble, 10 m, coll. M. Blazewicz-Paskowycz, 13 Feb 2009; AM W.46527, North Direction Island, Deep Reef slope, 14°44'36"S, 145°30'54"E, coral rubble, 2 m, coll. C. Watson; AM W.46528, North Direction Island, Deep Reef slope, 14°44'36"S, 145°30'54"E, coral rubble, 2 m, coll. C. Watson; AM W.46533, Coconut Beach, inter-reef sand, 14°40'54"S, 145°28'24"E, Halimeda and rubble, 2 m, coll. C. Watson, 7 Feb 2009; AM W.47451 stn. G241, Osprey Island, coll. G. Rouse & E. Kupriyanova, 31 Oct 2005; SAM E3596, stn.G236, east lagoon near Bird Islet, 9 m, coll. G. Rouse & E. Kupriyanova, 29 Oct 2005; ZMA V.Pol. 3449, near Bird Islet, grid C, from experimental fouling panels, coll. P. Hutchings & P. Weate, det H. ten Hove 1981, retained from AM W.16984 and AM W.16986 (2).

Diagnosis. Opercular verticil consists of 5–6 triangular spines curved inward, with a small external knob. Dorsal verticil spine larger than others, with elongated sharp tip, curved inward. Funnel radii with 18–25 chitinized pointed tips, base of funnel half chitinized ( Fig. 11 ). Tube often (but not always) bluish, dark brown or black inside.

Remarks. Specimens from Lizard Island (AM W.45474, AM W.45414, and AM W.45419) show more slender verticil spines than specimens from other localities. Lizard Island specimens have dark brown verticil spines and funnel radii tips, a large inward curved hook and sub-triangular ventral verticil spines. The external knob, which was considered to be one of the most important taxonomic characters (Imajima & ten Hove 1984) is not obvious in AM W.45474, AM W.45414, AM W.45419. However, our molecular data (Sun et al. unpubl.) show that these specimens belong to the same species as other specimens that have typical Hydroides tuberculata opercula.

Many Indo-West Pacific Hydroides nominal species are characterized by a low number of rather valvular verticil spines: H. adamaformis Pillai, 2009 , H. kimberleyensis Pillai, 2009 , H. perezi Fauvel, 1918 , H. rhombobula Chen & Wu, 1980 , H. tuberculata Imajima, 1976a , H. uniformis Imajima & ten Hove, 1986 and H. xishaensis Chen & Wu, 1978 . Hydroides tuberculata can be distinguished from H. kimberleyensis , H. rhombobula , H. uniformis and H. xishaensis by the presence of an enlarged dorsal verticil spine with external knob, while all verticil spines are equally sized and apparently smooth in the other nominal taxa. Hydroides tuberculata differs from H. perezi by the shape of the verticil spines, subtriangular in cross-section in H. tuberculata , but flat in H. perezi (ten Hove 1970; Imajima & ten Hove 1984). Additional studies are needed to determine whether H. perezi and H. tuberculata are separate species.

Distribution. Indo-West Pacific ( Micronesia, Melanesia, Southern Japan; NT, Qld, WA, Australia).

Figures

FIGURE 6. Hydroides longispinosa, opercula of fixed specimens, AM W. 42327 (bottom right), AM W. 42333 (the rest). Photo: E. Wong. Scale bars = 0.1 mm.

FIGURE 11. Hydroides tuberculata, live animals in tubes. A. AM W. 45055; B. Stn. G 236, SAM E 3596. Photo: A—A. Semenov, B— G. Rouse. Scale bars: A = 1 mm, B = 1 mm.

FIGURE 29. A. Spirobranchus latiscapus, operculum of fixed specimen (stained with methyl green), AM W. 201802; B. Sp. latiscapus, anterior end (stained with methyl green), AM W. 201837; C. Sp. nigranucha, dorsal view of radiolar crown showing lack of peduncle (arrow indicates a tonguelet), AM W. 41948; D. Close-up view of the same specimen (stained with methyl green). Photo: A – D—E. Wong. Scale bars: A – D = 1 mm.