Styela gibbsii Stimpson, 1864

Lambert, Gretchen, 2019, The Ascidiacea collected during the 2017 British Columbia Hakai MarineGEO BioBlitz, Zootaxa 4657 (3), pp. 401-436 : 422

Styela gibbsii Stimpson, 1864

Figure 11D

IHAK 12 Rocky intertidal across small by from Hakai dock. Several, very small, under rock.

IHAK 55 BHAK 1736 UF 2547. Kwakshua Petroglyph Cliff, Scuba, 17–20 m. Vertical rock wall, high current .

IHAK 60 BHAK 1739 UF 2550. Rattenbury Pinnacle, Scuba, 17–20 m. Covered with small barnacles .

MHAK 14 BHAK 0620. Tippy Rock Bay low intertidal. One on red alga Neorhodomela , tissue sample only.

ZHAK 35 Sasquatch Commode tidepool. One tiny specimen.

This species may reach 6 cm in length, although among the few small specimens collected in the current survey, none are more than 3 cm long. The siphons are both at the anterior end and may both point forward or sometimes one or the other may be curved. The body is elongate, slender and may or may not be curved. These body shape differences may be due to its habit of sometimes settling under the lower edges of rocks and irregularly growing outward. The tunic is tan and somewhat or very rugose; it usually has some shallow irregular longitudinal furrows which may or may not be crossed by shallow horizontal furrowing. There are two elongate ovaries per side, with numerous testes arranged along the posterior sides of the ovaries, somewhat similar to the warmer water Styela canopus (Savigny, 1816) , but the distributions of these two species do not overlap. There are usually 4–6 longitudinal vessels between each of the four pharyngeal folds on each side. A detailed morphology is given by Huntsman (1912b) and Van Name (1945). Distribution: Alaska to southern California ( Huntsman 1912b; Ritter & Forsyth 1917; Van Name 1945; Lamb & Hanby 2005.) It is often found as a fouling species on marina floats.

Figures

FIGURE 11. Styelidae. A: Cnemidocarpa finmarkiensis about 2 cm in width; B: Metandrocarpa dura; C: M. taylori; D: Styela gibbsii 1.7 cm in length; E: S. montereyensis, longest one 8 cm; F: S. truncata 2 cm in length. Scale bars: B, 1 mm; C, 2.5 mm. A and F photos by G. Paulay.