Halicornaria indivisa Fraser, 1936c

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 : 62-63

Halicornaria indivisa Fraser, 1936c

Halicornaria indivisa Fraser, 1936c: 52 , figs. 7a–d.

Haliaria indivisa .— Yamada, 1959: 83.

Gymnangium indivisum .— Vervoort & Watson, 2003: 286.

Syntype. BCPM 976-00857-001 : Japan, Sagami Bay ; slide.

Lectotype, by present designation. BCPM 976-00857-001 : Japan, Sagami Bay , one colony fragment, 1.2 cm high, in good condition, with gonophores; slide.

Type locality. Japan: Sagami Bay , 90 m ( Fraser 1936c).

Current status. Valid, as Gymnangium indivisum ( Fraser, 1936c) .

Remarks. Fraser (1936c) described Halicornaria indivisa from hydroids obtained by Emperor Hirohito at a depth of 90 m in Sagami Bay, Japan. No name-bearing types were designated by him in the original account of the species. Fraser described H. indivisa as “Colony large, 25 cm. in length…”, but the only specimen of the species in the Fraser Hydroid Collection at the RBCM (BCPM 976-00857-001) is a small fragment of a colony on a microscope slide. We nevertheless conclude that it is a type, possibly a fragment of the large colony described by Fraser. Rather than assume that it is the holotype by monotypy, however, we have designated the specimen as the lectotype of H. indivisa (ICZN Recommendation 73F).

Records of three collections of this species (as Haliaria indivisa ) in the Emperor Shōwa Hydroid Collection at NMNS (NSMT-HyR 1424–NSMT-HyR 1426) generally correspond with Fraser’s distribution data. Others (NSMT-HyR 1427–NSMT-HyR 1443) were obtained either at different depths or were collected after Fraser’s manuscript was presented at a meeting of the Royal Society of Canada in May, 1936.

This hydroid, now known as Gymnangium indivisum , is regarded as a valid species in WoRMS. The colony, described as robust and unbranched, attained a height of 25 cm. Better illustrations than those in Fraser (1936c) are provided by Hirohito (1995, as Haliaria indivisa ).