Halecium cymosum Fraser, 1935b

Calder, Dale R. & Choong, Henry H. C., 2018, Names of hydroids (Cnidaria, Hydrozoa) established by Charles McLean Fraser (1872 - 1946), excluding those from Allan Hancock Expeditions, Zootaxa 4487 (1), pp. 1-83 : 30-31

Halecium cymosum Fraser, 1935b

Halecium cymosum Fraser, 1935b: 107 , pl. 2, figs. 4a–d.

Syntypes. BCPM 976-00471-001 : Japan, Sagami Bay , Eboshi-iwa, “on tidal marks”, 19 April 1931, in poor condition; dry.

BCPM 976-00471-002 : Japan, Sagami Bay , Eboshi-iwa, “on tidal marks”, 19 April 1931, several colony fragments, up to 3 mm high, in fairly good condition, with gonophores; slide.

Lectotype, by present designation. RBCM 976-00471-003: Japan, Sagami Bay, Eboshi-iwa, “on tidal marks”, 19 April 1931, one colony fragment (middle colony on the slide BCPM 976-00471-002), 3 mm high, in fairly good condition, with gonophores; slide.

Paralectotypes. BCPM 976-00471-001 : Japan, Sagami Bay , Eboshi-iwa, “on tidal marks”, 19 April 1931, in poor condition; dry.

BCPM 976-00471-002 : Japan, Sagami Bay , Eboshi-iwa, “on tidal marks”, 19 April 1931, several colony fragments, up to 3 mm high, in fairly good condition, with gonophores; slide.

Type locality. Japan: Sagami Bay , Eboshi-iwa (as “ Yeboshi-iwa ”), at low tide ( Fraser 1935b).

Current status. Valid.

Remarks. Fraser (1935b) received specimens of Halecium cymosum , collected at Eboshiiwa in Sagami Bay by Emperor Hirohito, from Dr. Hirotaro Hattori. No name-bearing type was designated by him. Hydroids in the Fraser Hydroid Collection at the RBCM (BCPM 976-00471-001; BCPM 976-00471-002), listed above, are syntypes. The first of these, now dry, is in poor condition. However, specimens on the slide, having the same collection data, are in reasonably good condition. As a lectotype of the species, we designate the large colony fragment (RBCM 976- 00471-003), located in the middle of the slide (BCPM 976-00471-002). Gonophores are present on this specimen. All others on the slide, along with the dry collection (BCPM 976-00471-001), are paralectotypes.

Several records of H. cymosum were also documented by Hirohito (1995) in his collection. Data accompanying one sample (No. 1242, Sagami Bay , Eboshiiwa , 19 April 1931) correspond with those at the RBCM . The specimens are now at the NMNS in Japan (NSMT-HyR 1242). We do not know whether Fraser examined the material in the process of describing the species, and excluded it from the syntype series.

While colonies described by Fraser (1935b) reached a maximum height of 3 mm, others examined by Hirohito (1995) attained 10 mm high or more. Hirohito provided illustrations of the trophosome of H. cymosum , and of the male and female gonophores, complementing those of Fraser. The species is taken to be valid ( Hirohito 1995; WoRMS).