Fraser, 1941b : 82
Names of hydroids (Cnidaria, Hydrozoa) established by Charles McLean Fraser (1872 - 1946), excluding those from Allan Hancock Expeditions
Calder, Dale R.
Choong, Henry H. C.
Zootaxa
2018
2018-10-02
4487
1
1
83
74CHR
Fraser, 1941 b
Fraser
1941
[173,553,152,178]
Hydrozoa
Campanulariidae
Obelia
GBIF
Animalia
Leptothecata
70
71
Cnidaria
species
racemosa
? Obelia racemosa Fraser, 1941b: 82, pl. 15, fig. 7.
Holotype: USNM4883: Canada, Nova Scotia, Western Bank, 91–119 m, 0 7 June 1880, schooner Mist, one colony, 25 cmhigh ( Fraser 1941b), in poor condition, gonophores not seen, labelled “ syntype”; ethanol. Typelocality. Canada, Nova Scotia: Western Bankoff Cape Breton Island, 50–65 fm ( 91–119 m) ( Fraser 1941b). Current status. Species inquirenda.
Remarks.In being designated as the “ type”, material of Obelia racemosaat the NMNH (USNM 4883) was fixed as the name-bearing typeof the species by Fraser (1941b). Although listed as a syntypein the online database, the specimen count is given as “1.” Fraser’s (1941b)original account of the species implies that it was based on a single specimen, as his description began with the words “Colony large….” The typeexamined here, consisting of one colony and a few fragments of it, is considered the holotype. Obelia racemosahas not been reported again. The holotypespecimen is in poor condition, with no hydranths, little or no coenosarc, and few hydrothecae. Gonosomes were lacking in Fraser’s (1941b)hydroid, and he assigned the species to Obelia Péron & Lesueur, 1810with question. From his description and illustration, and from the typespecimen, however, we consider that generic assignment to be correct. The principal distinguishing characters of O. racemosaappear to be: (1) the stiff racemes formed by distal branchlets and pedicels, and (2) the densely clustered arrangement of the hydrothecae. Although regarded as a synonym of O. dichotoma( Linnaeus, 1758)in WoRMS, O. racemosasomewhat resembles O. plicata Hincks, 1868in its strongly polysiphonic colony form. The latter species too, however, is considered identical with O. dichotomain the current WoRMS list, likely following Cornelius (1990, 1995). Its general mode of branching is similar to O. longissima( Pallas, 1766), but the hydrocaulus of that species is usually monosiphonic. Further study is needed to explore the status of these putative species. Fraser’s hydroid was considered a valid species in Cairns et al. (2002), and listed as O. racemosa.
1915525889
Canada
105
Cape Breton Island
Western Bank
70
71
1
Nova Scotia
holotype