Sertularella conella Stechow, 1920

Choong, Henry H. C., 2015, Hydroids of the genus Sertularella (Cnidaria: Hydrozoa: Sertulariidae) from the Pacific coast of Canada in the collection of the Royal Ontario Museum, with descriptions of four new species, Zootaxa 3925 (3), pp. 387-408 : 392

Sertularella conella Stechow, 1920

( Figure 3 )

Sertularella conella — Stechow, 1920: 37.

Sertularella conica — Fraser, 1937:151, pl. 33, fig. 179.— Calkins, 1899:359, pl. 4, fig. 22 [not Sertularella conica Allman, 1877 ].

Material. CANADA: British Columbia. Northwest of Estevan Point, 49˚23’45”N, 126˚34’15”W, 0 2. vi.1934, dense colonies, without gonothecae, ROMIZ B4028. CANADA: British Columbia. Nootka Island. Bajo Point, 49˚36’45”N, 126˚49’00”W, 26. vi.1934, epizoic on Bryozoa ( Bugula sp), without gonothecae, ROMIZ B4029. CANADA: British Columbia. Nootka Island. Bajo Point, 49˚36’45”N, 126˚49’00”W, 26. vi.1934, epizoic on barnacle fragment, without gonothecae, ROMIZ B4030. CANADA: British Columbia. East of Tatchu Point, 49˚51’00”N, 127˚06’15”W, 28. vi.1934, hydrocauli, without gonothecae, ROMIZ B4031. CANADA: British Columbia. 11. vii.1934, epizoic on Bryozoa ( Bugula sp), with gonothecae, ROMIZ B4032. CANADA: British Columbia. Queen Charlotte Land District. Masset Harbor, 14. ix.1935, on Symplectoscyphus turgidus ( Trask, 1857) , without gonothecae, ROMIZ B4033. CANADA: British Columbia. Queen Charlotte Land District. Masset Harbor, 14. ix.1935, on Symplectoscyphus tricuspidatus ( Alder, 1856) , without gonothecae, ROMIZ B4034. CANADA: British Columbia. Swan Hill Locality, 54˚07’00”N, 131˚36’00”W, 21. iv. 1961,16.5 meters, without gonothecae, coll. D.B. Quayle, ROMIZ B4035. Other material: CANADA: British Columbia. Northwest of Estevan Point, 49˚23’45”N, 126˚34’15”W, 0 2. vi.1934, branched colony, without gonothecae, CMNI 1982-1268 (as Sertularella fusiformis ). CANADA: British Columbia. Nootka Island. Bajo Point, 49˚36’45”N, 126˚49’00”W, 26. vi.1934, dense colony on calcareous algae ( Bossiella sp.), without gonotheca, CMNI 1982-1237. CANADA: British Columbia. 11.vii.1934, branching hydrocauli, without gonothecae, CMNI 1982-1245 (as Sertularella conica ).

Reported distribution. Canada: Houston-Stewart Channel, Queen Charlotte Islands (=Haida Gwaii) to the San Juan archipelago ( Fraser 1937); Townsend Harbor (Port Townsend), Puget Sound ( Calkins 1899).

Description. Colonies dense, stoloniferous, hydrorhiza simple. Epizoic on Bryozoa, barnacle fragments, or Symplectoscyphus tricuspidatus . Unbranched or small branches, monosiphonic. Perisarc of hydrocaulus and hydrothecae thickened throughout, 30–120 mm. Axis divided into segments of oblique nodes, spiral, alternating left and right. Hydrothecae distant, slightly fusiform, narrowing distally, 1070–1300 mm in length; 620–680 mm maximum width. Hydrotheca less than 1/3 adnate, adnate side 830-990 mm long, 3–4 annulations only on the adcauline side, abcauline side smooth. Hydrothecal rim with four well-defined, sharp cusps. Intrathecal cusps present; one large abcauline, and two medium-to-small adcauline.

Gonothecae few, arising from stem, ovate, longer than wide, up to 3080 mm long, 1570 mm at the widest point, on short, indistinct stalk approximately 200 mm long. Five to six annulations spanning entire gonothecal body, distinct crest on rugosities, perisarc thickened. Four well-developed cusps surrounding gonothecal aperture, no distinct neck. Cusps sometimes folded inwards towards aperture.

Remarks. Stechow (1920) assigned the hydroids identified from the northwest coast of North America as Sertularella conica by Fraser (1911) to a new species, S. conella . Calder (1990) confirmed that several hydroids identified by Fraser as S. conica from the west coast of North America are not conspecific with S. conica Allman, 1877 based on the tilt of the hydrothecae to the adcauline side and prominent gonothecal cusps in Fraser’s material. Stechow (1920) mentions the lack of intrathecal cusps in S. conica Allman, 1877 . The material examined in this study corresponds to Fraser’s description of the hydroids he attributed to S. conica ; significantly, the appearance of annulations are present only on the adcauline side of the hydrothecae, and the gonothecae possess four prominent cusps which may be straight or curved inward.

Figures

FIGURE 3. Sertularella conella, ROMIZ B 4029: (A) Branch showing hydrothecae; (B) close-up of hydrothecae; (C) gonotheca; (D) detail of gonotheca cusps. Scale bars equal 1.0 mm.