Genus Endothecium Fraser, 1935b Endothecium Fraser, 1935b: 107 [invalid junior homonym of Endothecium Koker, 1924 (Anthozoa)]. Sagamihydra Hirohito, 1995: 41 [correct original spelling]. Sagamihyra Hirohito, 1995: 42 [incorrect original spelling]. Type species. Endothecium reduplicatum Fraser, 1935b, by monotypy. Current status. Invalid. Remarks. Endothecium Fraser, 1935b is an invalid junior homonym of Endothecium Koker, 1924: 22 (Anthozoa). Hirohito (1995) proposed Sagamihydra as a replacement name for the junior homonym, although he misspelled it as Sagamihyra on page 42 in the same publication. For the record, Sagamihydra is taken here to be the correct original spelling under the First Reviser Principle (ICZN 24.2.3). In the WoRMS list, Sagamihydra is currently included in the synonymy of Halecium Oken, 1815, but the genus is considered valid here in having hydranths with an intertentacular web, a cnidome comprising large haplonemes in addition to microbasic mastigophores, and gonophores that arise from within the hydrothecal cavity (Calder 1991; Hirohito 1995).

Published as part of 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, pp. 1-83 in Zootaxa 4487 (1) on page 28, DOI: 10.11646/zootaxa.4487.1.1, http://zenodo.org/record/1456161