Brinckmann-Voss Anita, Calder Dale R
Invertebrate Zoology Section, Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, Canada M5S 2C6.
Zootaxa. 2013;3666:389-97. doi: 10.11646/zootaxa.3666.3.9.
Zyzzyzus rubusidaeus, sp. nov., is described from inshore waters near the northern tip of Vancouver Island, British Columbia, Canada. Specimens were collected on rocky bottoms amongst barnacles, sponges, and compound ascidians at a depth of 18 m in Weynton Passage, Broughton Strait, during March, July, and October 2012. Polyps tend to grow in dense aggregations, often covering several square centimetres. Hydroids of Z. rubusidaeus most closely resemble those of Z. robustus Petersen, 1990 from Greenland, but differ in having aboral tentacles that are scattered in a narrow band around the base of the hydranth rather than occurring in a single whorl, thin and transparent instead of thick and stiff perisarc around hydrocaulus and tubers, and gonophores that arise from simple pedicels instead of short, stout branches. Possible embryos were present in female gonophores, although structures recognizable as actinula larvae have not been observed. The cnidome comprises small and large stenoteles, desmonemes, microbasic euryteles, basitrichs, and isorhizas. Polyps are a raspberry colour in life, a hue that has faded but little in our formalin-preserved material. Discovery of this hydroid brings the number of species currently recognized in genus Zyzzyzus Stechow, 1921 to seven.
新物种红醋栗枝螅（Zyzzyzus rubusidaeus）是在加拿大不列颠哥伦比亚省温哥华岛北端附近的近岸水域发现的。2012年3月、7月和10月期间，在布劳顿海峡韦恩顿水道18米深处的附着有藤壶、海绵和复合海鞘的岩石底部采集到了标本。水螅体倾向于密集聚集生长，常常覆盖几平方厘米的面积。红醋栗枝螅的水螅体与1990年来自格陵兰岛的粗壮枝螅（Z. robustus Petersen）最为相似，但不同之处在于其反口触手分散在水螅体基部周围的一条窄带中，而非呈单个轮生，围绕水螅茎和瘤体的围鞘薄且透明，而非厚且硬，生殖体从简单的花梗上长出，而非短而粗壮的分支上长出。雌性生殖体内存在可能的胚胎，不过尚未观察到可识别为辐射幼虫的结构。刺丝囊包括小型和大型的等刺丝囊、束状刺丝囊、微基宽刺丝囊、基须刺丝囊和等根刺丝囊。水螅体在生活中呈覆盆子色，在我们用福尔马林保存的标本中这种颜色褪去不多。这种水螅的发现使目前在枝螅属（Zyzzyzus Stechow，1921）中被认可的物种数量增至七个。
